ORCID Profile
0000-0003-2792-0811
Current Organisations
University of Arizona
,
University of Tasmania
Does something not look right? The information on this page has been harvested from data sources that may not be up to date. We continue to work with information providers to improve coverage and quality. To report an issue, use the Feedback Form.
Publisher: Springer Science and Business Media LLC
Date: 22-09-2020
Publisher: Pan American Health Organization
Date: 16-07-2022
Abstract: Global Hearts is the flagship initiative of the World Health Organization to reduce the burden of cardiovascular diseases, the leading cause of death and disability worldwide. HEARTS in the Americas Initiative is the regional adaptation that envisions HEARTS as the model for cardiovascular disease risk management, including hypertension and diabetes, in primary health care in the Americas by 2025. This initiative is entering its sixth year of implementation and now includes 22 countries and 1 380 primary health care centers. The objectives of this report are three-fold. First, it describes the emergence and the main elements of HEARTS in the Americas. Secondly, it summarizes the main innovations developed to catalyze and sustain implementation of the initiative. These innovations include: a) introduction of hypertension control drivers b) development of a comprehensive and practical clinical pathway c) development of a strategy to improve the accuracy of blood pressure measurement d) creation of a monitoring and evaluation platform and e) development of a standardized set of training and education resources. Thirdly, this report discusses future priorities of the initiative. The goal of implementing these innovative and pragmatic solutions is to create a more effective health system and shift the focus of cardiovascular and hypertension programs from the highly specialized care level to primary health care. In addition, HEARTS in the Americas can serve as a model for more comprehensive, effective, and sustainable noncommunicable disease prevention and treatment practices.
Publisher: BMJ
Date: 07-2020
DOI: 10.1136/BMJOPEN-2020-036977
Abstract: Obtaining informed consent is a cornerstone requirement of conducting ethical research. Traditional paper-based consent is often excessively lengthy and may fail to achieve the desired participant understanding of study requirements. Multimedia tools including video and audio may be a useful alternative. This study aimed to determine the efficacy, usability and acceptability of self-directed multimedia delivery of participant consent. It is a single-centre, randomised, prospective study to determine the efficacy, usability and acceptability of a self-directed multimedia consent process (intervention) compared with the traditional paper-based approach (control). The intervention was free of research staff, with computer-based finger-signed consent. Pathology blood collection services in Tasmania, Australia. 298 participants (63±8 years 51% female in iduals) referred from general practice were randomised to intervention (n=146) and control (n=152). Efficacy, usability and acceptability of the allocated consent process were assessed by a questionnaire. All participants successfully completed the allocated interventions. Efficacy parameters were higher among intervention participants, including a better understanding of study requirements compared with controls (p .05 all). Intervention participants were more likely to engage with the study information and spend more time on the consent process (p= .001 and p=0.006, respectively). Both groups reported similar levels of acceptability, although more control participants reported that the study information was too long (24% vs 14% p=0.020). A self-directed multimedia consent process is effective for achieving participant understanding and obtaining consent free of research staff. Thus, multimedia represents a viable method to reduce the burden on researchers, meet participant needs and achieve informed consent in clinical research.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 12-2019
DOI: 10.1161/HYPERTENSIONAHA.119.13461
Abstract: Physical activity (PA) is a preventative behavior for noncommunicable disease. However, little consideration is given as to whether different domains of PA have differing associations with health outcomes. We sought to determine the association between occupational, sport, leisure, and total PA with baroreflex sensitivity (BRS), distinguishing between neural (nBRS) and mechanical (mBRS) BRS. In a cross-sectional analysis of 8649 adults aged 50 to 75 years, resting nBRS (estimated by low-frequency gain, from carotid distension rate and heart rate) and mBRS (carotid stiffness) were measured by high-precision carotid echo-tracking. PA was self-reported using the validated Baecke questionnaire. The associations between PA and nBRS and mBRS were quantified using multivariate linear regression analysis, separately in the working and nonworking population. In working adults (n=5039), occupational PA was associated with worse nBRS (unstandardized β=−0.02 [95% CI, −0.04 to −0.003] P =0.022) whereas sport PA was associated with better nBRS (β=0.04 [95% CI, 0.02–0.07] P =0.003) and mBRS (β=−0.05 [95% CI, −0.09 to −0.00001] P =0.049). Neither leisure PA nor total PA was associated with nBRS or mBRS. In nonworking adults (n=3610), sport PA and total PA were associated with better mBRS (β=−0.08 [95% CI, −0.15 to 0.02] P =0.012 and β=−0.05 [95% CI, −0.10 to 0.009] P =0.018) but not nBRS. These findings suggest differential associations between domains of PA and BRS and may provide insights into the mechanisms underlying the association between occupational PA and cardiovascular disease.
Publisher: Springer Science and Business Media LLC
Date: 2017
DOI: 10.1007/S11906-017-0704-7
Abstract: The purpose of the review is to examine whether measurement of aortic stiffness could be especially value-adding for risk stratification and treatment among patients with resistant hypertension (RH). Adverse arterial remodeling and increased aortic stiffness is associated with RH, and it may be of additional clinical benefit to measure aortic stiffness in these patients. However, there is insufficient evidence to determine whether aortic stiffness is excessively high relative to the level of blood pressure (BP) among people with RH. This issue needs resolution as it could help refine management decisions guided by aortic stiffness. If conventional antihypertensive therapy fails to lower BP in patients with RH, there is good rationale for effectiveness of spironolactone as add on therapy, and this should also improve aortic stiffness. Lifestyle intervention with exercise and diet should be additionally efficacious towards improving BP and aortic stiffness in patients with RH, but there is limited data in this patient population. For better characterization on the effects of BP treatment on aortic stiffness, measures of central aortic BP may help refine management decisions above and beyond conventional arm cuff BP. There is strong evidence to support the use of aortic stiffness as a tool to aid risk stratification in hypertension management. Although there is a theoretical basis for special additional benefit of measuring aortic stiffness in patients with RH (as distinct from uncomplicated hypertension), at this time, there is inadequate data available to make definitive conclusions and is an area for future investigation.
Publisher: Springer Science and Business Media LLC
Date: 2015
Publisher: Oxford University Press (OUP)
Date: 17-06-2016
DOI: 10.1093/AJH/HPW063
Abstract: New techniques that measure central blood pressure (BP) using an upper arm cuff-based approach require performance assessment. The aim of this study was to compare a cuff-based device (CuffCBP) to estimate central BP indices (systolic BP (SBP), diastolic BP (DBP), pulse pressure (PP), augmentation pressure (AP), augmentation index (AIx)) with noninvasive radial tonometry (TonCBP). Consecutive CuffCBP (SphygmoCor Xcel) and TonCBP (SphygmoCor 8.1) duplicate recordings were measured in 182 people with treated hypertension (aged 61±7 years, 48% male). Agreement between methods was assessed using standard calibration with brachial SBP and DBP (measured with the Xcel device), as well as with brachial mean arterial pressure (MAP 40% form factor method) and DBP. The mean difference ± SD for central SBP (cSBP), central DBP (cDBP), and central PP (cPP) between methods were -0.89±3.48mm Hg (intra-class correlation (ICC) 0.977 95% confidence interval (CI) 0.973-0.982), -0.50±1.54mm Hg (ICC 0.992, 95% CI 0.987-0.993), and -0.42±3.57mm Hg (ICC 0.966, 95% CI 0.958-0.972), indicating good agreement. Wider limits of agreement were observed for central AP (cAP) and central AIx (cAIx) (-0.91±5.31mm Hg ICC 0.802 95% CI 0.756-0.839, -0.99±10.91% ICC 0.749 95% CI 0.691-0.796). Re-calibration with brachial MAP and DBP resulted in an overestimation of cSBP with CuffCBP compared with TonCBP (8.58±19.06mm Hg, ICC 0.164, 95% CI -0.029 to 0.321). cSBP, cDBP, and cPP derived from CuffCBP are substantially equivalent to TonCBP, although the level of agreement is dependent on calibration method. Further validity testing of CuffCBP by comparison with invasively measured central BP will be required.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 06-2007
Publisher: American Medical Association (AMA)
Date: 02-05-2023
Abstract: This study examines the availability, cost, and consumer ratings of blood pressure–measuring devices relative to validation status across 10 countries.
Publisher: Springer Science and Business Media LLC
Date: 02-10-2014
DOI: 10.1038/JHH.2014.84
Abstract: Blood pressure (BP) is a mandatory safety measure during graded intensity clinical exercise stress testing. While it is generally accepted that exercise hypotension is a poor prognostic sign linked to severe cardiac dysfunction, recent meta-analysis data also implicate excessive rises in submaximal exercise BP with adverse cardiovascular events and mortality, irrespective of resting BP. Although more data is needed to derive submaximal normative BP thresholds, the association of a hypertensive response to exercise with increased cardiovascular risk may be due to underlying hypertension that has gone unnoticed by conventional resting BP screening methods. Delayed BP decline during recovery is also associated with adverse clinical outcomes. Thus, above and beyond being used as a routine safety measure during stress testing, exercise (and recovery) BP may be useful for identifying high-risk in iduals and also as an aid to optimise care through appropriate follow-up after exercise stress testing. Accordingly, careful attention should be paid to correct measurement of exercise stress test BP (before, during and after exercise) using a standardised approach with trained operators and validated BP monitoring equipment (manual or automated). Recommendations for exercise BP measurement based on consolidated international guidelines and expert consensus are presented in this review.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 06-2018
DOI: 10.1161/HYPERTENSIONAHA.117.10696
Abstract: Cuff blood pressure (BP) is the reference standard for management of high BP, but the method is inaccurate and can lead to BP misclassification. The aims of this study were to determine whether distinctive BP phenotypes exist based on BP transmission ( lification) variability from central-to-peripheral arteries and whether applying one standard cuff BP measurement approach (eg, oscillometry) to all people could discriminate the BP phenotypes. Intra-arterial BP was measured at the ascending aorta and brachial and radial arteries in 126 participants (61±10 years 69% male) after coronary angiography. Central-to-peripheral systolic BP (SBP) transmission (SBP lification) was defined by ≥5 mm Hg SBP increase between the aorta-to-brachial or brachial-to-radial arteries. Standard cuff BP was measured 4 different times using 3 different devices. Three independent investigators also provided data (n=255 from 4 studies) using another 3 separate cuff BP devices. Four distinct BP phenotypes were discovered based on variability in SBP lification: phenotype 1, both aortic-to-brachial and brachial-to-radial SBP lification phenotype 2, only aortic-to-brachial SBP lification phenotype 3, only brachial-to-radial SBP lification and phenotype 4, neither aortic-to-brachial nor brachial-to-radial SBP lification. Aortic SBP was significantly higher among phenotypes 3 and 4 compared with phenotypes 1 and 2 ( P =0.00074), but this was not discriminated using any standard cuff BP measures ( P =0.31). Data from independent investigators confirmed the key findings. This is the first-in-human discovery of BP phenotypes that have significantly different BPs, but which are not discriminated by standard cuff BP devices used in daily clinical practice. Improved BP device accuracy may be achieved by considering in idual phenotypic BP differences.
Publisher: Springer Science and Business Media LLC
Date: 2017
Publisher: Springer Science and Business Media LLC
Date: 25-12-2015
DOI: 10.1007/S00421-014-3087-3
Abstract: A hypertensive response to moderate intensity exercise (HRE) is associated with increased cardiovascular risk. The mechanisms of an HRE are unclear, although previous studies suggest this may be due to haemostatic and/or haemodynamic factors. We investigated the relationships between an HRE with haemostatic and hemodynamic indices. Sixty-four participants (57 ± 10 years, 71 % male) with indication for exercise stress testing underwent cardiovascular assessment at rest and during moderate intensity exercise, from which 20 participants developed an HRE (defined as moderate exercise systolic BP ≥ 170 mmHg/men and ≥ 160 mmHg/women). Rest, exercise and post-exercise blood s les were analysed for haemostatic markers, including von Willebrand factor (vWf), and haemodynamic measures of brachial and central blood pressure (BP), aortic stiffness and systemic vascular resistance index (SVRi). HRE participants had higher rest vWf compared with normotensive response to exercise (NRE) participants (1,927 mU/mL, 95 % CI 1,240-2,615, vs. 1,129 mU/mL, 95 % CI 871-1,386 p = 0.016). vWf levels significantly decreased from rest to post-exercise in HRE participants (p = 0.005), whereas vWf levels significantly increased from rest to exercise in NRE participants (p = 0.030). HRE participants also had increased triglycerides, rest BP, aortic stiffness and exercise SVRi (p < 0.05 for all). Rest vWf predicted exercise brachial systolic BP (β = 0.220, p = 0.043 adjusted R (2) = 0.451, p < 0.001) independent of age, sex, body mass index, triglycerides, rest brachial systolic BP and aortic stiffness. Increased rest blood levels of vWf are independently associated with moderate intensity exercise systolic BP. These findings implicate abnormalities in haemostasis as a possible factor contributing to HRE at moderate intensity.
Publisher: Oxford University Press (OUP)
Date: 06-2008
DOI: 10.1038/AJH.2008.166
Abstract: A hypertensive response to exercise has prognostic significance. Patients with type 2 diabetes have vascular abnormalities which may predispose to exaggerated brachial and central blood pressure (BP) during exercise. This study aimed to test this hypothesis and to determine the clinical significance of high exercise BP by examining its relation to left ventricular (LV) mass. Brachial and central BP were recorded at rest and in response to maximal exercise in 73 diabetic patients (aged 54 +/- 10 years) and 73 controls (aged 53 +/- 12 years). Brachial BP was recorded using mercury sphygmomanometry and LV mass using 2D-echocardiography. Central BP was estimated by radial tonometry using an exercise-validated generalized transfer function. At rest there were no significant (P > 0.05) differences between groups in brachial or central BP. The diabetic patients had significantly increased exercise brachial systolic BP (SBP: 199 +/- 25 mm Hg vs. 185 +/- 21 mm Hg P = 0.002) and central SBP (158 +/- 17 mm Hg vs. 149 +/- 15 mm Hg P = 0.002). There was a significantly higher prevalence of an exaggerated exercise BP response (> or =210/105 mm Hg men and > or =190/105 mm Hg women) in the diabetic patients (51% vs. 22% P < 0.01). Compared with those with normal exercise BP, LV relative wall thickness (RWT) was significantly higher (0.41 +/- 0.09 vs. 0.36 +/- 0.08 P < 0.05) and LV hypertrophy was more prevalent (35% vs. 16% P < 0.05) in those with a hypertensive response. After accounting for other confounding variables, exercise central SBP remained independently associated with LV RWT (beta = 0.22 P = 0.006). Diabetic patients are more likely to exhibit exaggerated exercise BP. Regardless of disease status, high exercise central SBP may contribute to cardiovascular risk via adverse cardiac remodeling.
Publisher: Springer Science and Business Media LLC
Date: 03-07-2008
DOI: 10.1038/JHH.2008.71
Abstract: Central systolic blood pressure (SBP) may differ between in iduals with similar brachial SBP, which may have implications for risk assessment. This study aimed to determine the variation and potential clinical value of central SBP between patients with similar brachial SBP. Brachial SBP was measured by sphygmomanometer and central SBP by radial tonometry in 675 people (430 men), comprising healthy in iduals (n = 222), patients with known or suspected coronary artery disease (n = 229) and diabetes (n = 224). In iduals were stratified by brachial SBP in accordance with European Society of Hypertension guidelines (optimal, normal, high-normal, grades 1, 2 and 3 hypertension). The potential clinical value of central SBP was determined from the percentage of patients re-classified into different brachial SBP groups due to the difference between brachial and aortic SBP (defined as brachial SBP-central SBP). Central SBP increased with each brachial SBP level (optimal to grade 3 hypertension P < 0.001 for all). However, large variation in brachial-aortic SBP difference occurred within each brachial SBP group (range 2-33 mm Hg), resulting in sizeable overlap of central SBP between brachial SBP groups. For patients with normal brachial SBP, 96% had central SBP within the range of patients with high-normal brachial SBP, as well as 64% within the range of patients with grade 1 hypertension. We conclude that wide variation in brachial-aortic SBP difference occurs between patients with similar brachial SBP. This results in a significant overlap of central SBP scores between brachial SBP risk groups. This is likely to have treatment implications but remains to be tested.
Publisher: Oxford University Press (OUP)
Date: 2009
DOI: 10.1038/AJH.2008.284
Publisher: Elsevier BV
Date: 05-2015
DOI: 10.1016/J.MOLCEL.2015.04.024
Abstract: Multicellular organisms depend on cell-type-specific ision of labor for survival. Specific cell types have their unique developmental program and respond differently to environmental challenges, yet are orchestrated by the same genetic blueprint. A key challenge in biology is thus to understand how genes are expressed in the right place, at the right time, and to the right level. Further, this exquisite control of gene expression is perturbed in many diseases. As a consequence, coordinated physiological responses to the environment are compromised. Recently, innovative tools have been developed that are able to capture genome-wide gene expression using cell-type-specific approaches. These novel techniques allow us to understand gene regulation in vivo with unprecedented resolution and give us mechanistic insights into how multicellular organisms adapt to changing environments. In this article, we discuss the considerations needed when designing your own cell-type-specific experiment from the isolation of your starting material through selecting the appropriate controls and validating the data.
Publisher: Springer Science and Business Media LLC
Date: 19-01-2017
DOI: 10.1038/HR.2016.181
Publisher: Oxford University Press (OUP)
Date: 04-2008
DOI: 10.1038/AJH.2008.11
Publisher: Wiley
Date: 06-10-2020
DOI: 10.1111/JCH.14058
Publisher: Elsevier BV
Date: 03-2009
DOI: 10.1016/J.JSAMS.2008.10.009
Abstract: Hypertension (high blood pressure BP) is a leading contributor to premature death and disability from cardiovascular disease. Lifestyle modification that includes regular physical activity is often recommended to patients with hypertension as one of the first line treatments for lowering BP, as well as improving overall risk for cardiovascular events. It is recognised that allied health care professionals play an important role in helping patients to achieve BP control by influencing and reinforcing appropriate lifestyle behavior. The minimum amount of exercise that is recommended in patients with hypertension comprises a mix of moderate to vigorous aerobic (endurance) activity (up to 5 days/week) in addition to resistance (strength) training (on 2 or more non-consecutive days/week). However, due to the dose-response relationship between physical activity and health, exercise levels performed beyond the minimum recommendations are expected to confer additional health benefits. Vigorous exercise training is generally safe and well tolerated by most people, including those with hypertension, although some special considerations are required and these are discussed in this review.
Publisher: S. Karger AG
Date: 2016
DOI: 10.1159/000452742
Abstract: There is a plausible physiological theory, supported by many observational studies, that vitamin D supplementation should be effective for improving cardiovascular end points, such as blood pressure (BP), large artery stiffness, atherosclerosis, endothelial function and clinical events. However, results from randomised controlled trials (RCTs) have been inconsistent. In this review, we evaluated the evidence regarding the effectiveness of vitamin D supplementation for cardiovascular surrogate and hard clinical end points. RCTs were assessed in terms of s le size, duration of supplementation, baseline vitamin D level inclusion criteria (i.e., absence of vitamin D deficiency), dosage of vitamin D and population under investigation. Forty-five RCTs were identified. Eight RCTs with BP and 6 RCTs with large artery stiffness as the end points were found to comply with guidelines for the optimal design of clinical trials evaluating nutrient effects. Only 2 of the RCTs with an optimal design were effective in decreasing BP with vitamin D supplementation, although these were of moderate s le size ( ) and very short duration (8 weeks for both), whilst no RCT was effective in reducing large artery stiffness. Similar results were observed for atherosclerotic and endothelial function markers as end points. Only 1 RCT reported cardiovascular events as an end point and found neither increased nor decreased incident cardiovascular events over 7 years of follow-up. In conclusion, results from published RCTs indicate that vitamin D supplementation is ineffective in improving cardiovascular health among various patient populations, including in the presence or absence of vitamin D deficiency.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 12-2018
DOI: 10.1161/HYPERTENSIONAHA.118.11975
Abstract: Blood pressure (BP) in young adults predicts BP in later life. We aimed to identify metabolic, hemodynamic, and autonomic characteristics associated with raised BP in young adults and whether these differ between males and females. Three thousand one hundred forty-five healthy subjects, aged 18 to 40 years, were grouped according to sex and BP category following the recent reclassification of BP as part of American Heart Association/American College of Cardiology 2017 guidelines. All in iduals undertook a lifestyle and medical history questionnaire and detailed metabolic, hemodynamic, and autonomic assessments. Stage 1 hypertension and normal BP were the most common BP phenotypes in males (29%) and females (68%), respectively. In both sexes, cardiac output was positively associated with increasing BP category ( P .001 for both). Similar positive trends were observed for heart rate and stroke volume in males ( P .001 for both) and heart rate in females ( P .001). Unlike in males, peripheral vascular resistance, aortic pulse wave velocity, and augmentation index were significantly increased in hypertensive females ( P .001 for all) compared with the other BP categories. Most heart rate variability indices decreased across the BP categories, particularly in males. In young adults, metabolic and hemodynamic abnormalities associated with hypertension are already present at the elevated BP stage and the overall phenotype differed markedly between sexes. Whereas a cardiac phenotype was associated with elevated BP and hypertension in males, a vascular phenotype, characterized by elevated peripheral vascular resistance, aortic pulse wave velocity, and augmentation index, was dominant in females.
Publisher: Springer Science and Business Media LLC
Date: 11-07-2022
DOI: 10.1038/S41371-022-00706-9
Abstract: The aim of the HEARTS in the Americas initiative is to promote the adoption of global best practices in the prevention and control of cardiovascular diseases, and improve the control of hypertension. HEARTS is being implemented in 21 countries and a erse set of actions and measures are in progress to improve exclusive access in primary health care facilities to automated blood pressure measuring devices that have been validated for accuracy. The purpose of this manuscript is to illustrate these efforts, mainly in the regulatory and public procurement arena, and to present information on common challenges and solutions identified. Ex les from six countries confirm the need for not only a robust regulatory framework to increase availability of validated automated blood pressure measuring devices but also a comprehensive strategic approach that involves relevant stakeholders, includes a multi-pronged approach and is associated with a national program to prevent and control non communicable diseases.
Publisher: Springer Science and Business Media LLC
Date: 2017
Publisher: Springer Science and Business Media LLC
Date: 29-08-2018
DOI: 10.1007/S00421-018-3972-2
Abstract: It is widely thought that excess pulsatile pressure from increased stiffness of large central arteries (macro-vasculature) is transmitted to capillary networks (micro-vasculature) and causes target organ damage. However, this hypothesis has never been tested. We sought to examine the association between macro- and micro-vasculature waveform features in patients with type 2 diabetes (i.e., those with elevated stiffness T2D) compared with non-diabetic controls. Among 13 T2D (68 ± 6 years, 39% male) and 15 controls (58 ± 11 years, 40% male) macro-vascular stiffness was determined via aortic pulse wave velocity (aPWV) and macro-vascular waveforms were measured using radial tonometry. Forearm micro-vascular waveforms were measured simultaneously with macro-vascular waveforms via low power laser Doppler fluxmetry. Augmentation index (AIx) was derived on macro- and micro-vascular waveforms. Target organ damage was assessed by estimated glomerular filtration rate (eGFR) and central retinal artery equivalent (CRAE). aPWV was higher among T2D (9.3 ± 2.5 vs 7.5 ± 1.4 m/s, p = 0.046). There was an obvious pulsatile micro-vascular waveform with qualitative features similar to macro-vasculature pressure waveforms. In all subjects, macro- and micro-vasculature AIx were significantly related (r = 0.43, p = 0.005). In T2D alone, micro-vasculature AIx was associated with eGFR (r = - 0.63, p = 0.037), whereas in controls, macro-vasculature AIx and AP were associated with CRAE (r = - 0.58, p = 0.025 and r = - 0.61, p = 0.015). Macro- and micro-vasculature waveform features are related however, micro-vasculature features are more closely related to markers of target organ damage in T2D. These findings are suggestive of a possible interaction between the macro- and micro-circulation.
Publisher: Springer Science and Business Media LLC
Date: 10-2021
Publisher: American Diabetes Association
Date: 07-2005
DOI: 10.2337/DIACARE.28.7.1643
Abstract: OBJECTIVE—Type 2 diabetes is associated with reduced exercise capacity, but the cause of this association is unclear. We sought the associations of impaired exercise capacity in type 2 diabetes. RESEARCH DESIGN AND METHODS—Subclinical left ventricular (LV) dysfunction was sought from myocardial strain rate and the basal segmental diastolic velocity (Em) of each wall in 170 patients with type 2 diabetes (aged 56 ± 10 years, 91 men), good quality echocardiographic images, and negative exercise echocardiograms. The same measurements were made in 56 control subjects (aged 53 ± 10 years, 29 men). Exercise capacity was calculated in metabolic equivalents, and heart rate recovery (HRR) was measured as the heart rate difference between peak and 1 min after exercise. In subjects with type 2 diabetes, exercise capacity was correlated with clinical, therapeutic, biochemical, and echocardiographic variables, and significant independent associations were sought using a multiple linear regression model. RESULTS—Exercise capacity, strain rate, Em, and HRR were significantly reduced in type 2 diabetes. Exercise capacity was associated with age (r = −0.37, P & 0.001), male sex (r = 0.26, P = 0.001), BMI (r = −0.19, P = 0.012), HbA1c (A1C r = −0.22, P = 0.009), Em (r = 0.43, P & 0.001), HRR (r = 0.42, P & 0.001), diabetes duration (r = −0.18, P = 0.021), and hypertension history (r = −0.28, P & 0.001). Age (P & 0.001), male sex (P = 0.007), BMI (P = 0.001), Em (P = 0.032), HRR (P = 0.013), and A1C (P = 0.0007) were independent predictors of exercise capacity. CONCLUSIONS—Reduced exercise capacity in patients with type 2 diabetes is associated with diabetes control, subclinical LV dysfunction, and impaired HRR.
Publisher: Wiley
Date: 25-09-2023
DOI: 10.1111/SMS.14480
Publisher: Oxford University Press (OUP)
Date: 10-2004
DOI: 10.1093/QJMED/HCH104
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 11-2017
Publisher: The Royal Australian College of General Practitioners
Date: 04-2023
Publisher: Springer Science and Business Media LLC
Date: 13-06-2013
Publisher: Springer Science and Business Media LLC
Date: 24-02-2022
Publisher: Springer Science and Business Media LLC
Date: 29-09-2022
DOI: 10.1007/S00125-021-05572-7
Abstract: Microvascular blood flow (MBF) increases in skeletal muscle postprandially to aid in glucose delivery and uptake in muscle. This vascular action is impaired in in iduals who are obese or have type 2 diabetes. Whether MBF is impaired in normoglycaemic people at risk of type 2 diabetes is unknown. We aimed to determine whether apparently healthy people at risk of type 2 diabetes display impaired skeletal muscle microvascular responses to a mixed-nutrient meal. In this cross-sectional study, participants with no family history of type 2 diabetes (FH-) for two generations (n = 18), participants with a positive family history of type 2 diabetes (FH+ i.e. a parent with type 2 diabetes n = 16) and those with type 2 diabetes (n = 12) underwent a mixed meal challenge (MMC). Metabolic responses (blood glucose, plasma insulin and indirect calorimetry) were measured before and during the MMC. Skeletal muscle large artery haemodynamics (2D and Doppler ultrasound, and Mobil-O-graph) and microvascular responses (contrast-enhanced ultrasound) were measured at baseline and 1 h post MMC. Despite normal blood glucose concentrations, FH+ in iduals displayed impaired metabolic flexibility (reduced ability to switch from fat to carbohydrate oxidation vs FH- p < 0.05) during the MMC. The MMC increased forearm muscle microvascular blood volume in both the FH- (1.3-fold, p < 0.01) and FH+ (1.3-fold, p < 0.05) groups but not in participants with type 2 diabetes. However, the MMC increased MBF (1.9-fold, p < 0.01), brachial artery diameter (1.1-fold, p < 0.01) and brachial artery blood flow (1.7-fold, p < 0.001) and reduced vascular resistance (0.7-fold, p < 0.001) only in FH- participants, with these changes being absent in FH+ and type 2 diabetes. Participants with type 2 diabetes displayed significantly higher vascular stiffness (p < 0.001) compared with those in the FH- and FH+ groups however, vascular stiffness did not change during the MMC in any participant group. Normoglycaemic FH+ participants display impaired postprandial skeletal muscle macro- and microvascular responses, suggesting that poor vascular responses to a meal may contribute to their increased risk of type 2 diabetes. We conclude that vascular insulin resistance may be an early precursor to type 2 diabetes in humans, which can be revealed using an MMC.
Publisher: American Medical Association (AMA)
Date: 15-02-2022
Publisher: Wiley
Date: 19-11-2019
DOI: 10.1111/JCH.13735
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 11-2005
DOI: 10.1249/01.MSS.0000176305.51360.7E
Abstract: To quantify the rate of arterial oxygen desaturation during apnea in free ers. Ten free ers and ten controls undertook five maximal face immersion apneas in 10 degrees C water separated by 2 min of recovery. Electrocardiogram (ECG), blood pressure, and pulse oximetry were recorded continuously. Peripheral blood flow was measured by calf plethysmography every 30 s, and venous blood s les were collected at rest and after apneas 1, 3, and 5. The blood was analyzed for hematocrit (Hct), lactate, and hemoglobin (Hb) concentration. The arterial oxygen saturation (SaO(2)) data were curve fitted with both a sigmoid and two-slope continuous function. Apnea duration increased with successive attempts, with free ers achieving significantly longer maximal apneas (trained 246 +/- 44 s, untrained 129 +/- 39 s, P < 0.001). Compared with controls, free ers displayed a significant change from baseline in heart rate (trained -27.2 +/- 9.5 bpm, untrained -19.7 +/- 9.3 bpm, P < 0.001) and mean arterial pressure (MAP) (trained 48 +/- 20.7 mm Hg, untrained 37 +/- 10.0 mm Hg, P = 0.002), but no difference existed in peripheral blood flow, Hct, lactate, or Hb. The maximal slope of the SaO(2) sigmoid curve was not significantly different between the groups (trained -0.16 +/- 0.05%.s(-1), untrained -0.15 +/- 0.06%.s(-1), P = 0.26), but the DeltaSaO(2(/Deltat obtained from the two-slope continuous model indicated that 85% of the variance in the free ers DeltaSaO(2)/Deltat could be explained by the apnea-induced bradycardia, preapnea vital capacity, and Hb concentration. The sigmoidal function provided no quantifiable difference in the rate of oxygen desaturation. The two-slope continuous method, however, indicated that free ers who had larger oxygen stores and produced the largest bradycardia were able to slow the DeltaSaO(2)/Deltat to two to three times that of the least marked response.
Publisher: Oxford University Press (OUP)
Date: 30-08-2009
DOI: 10.1093/EJECHOCARD/JEP103
Abstract: Previous research has described differences in left ventricular (LV) systolic tissue velocity between genders. This study aimed to determine the association between LV tissue velocity and LV size in healthy controls and in those with type 2 diabetes (T2DM). LV tissue velocities were measured in 71 controls and 222 patients with T2DM by pulsed-wave Doppler and colour-coded tissue Doppler (TDI) during systole (S' and S(m)) and diastole (early, E' and E(m), and late, A' and A(m)) at the basal septum and lateral wall. Both systolic tissue velocities were higher in males than in females within controls (S': 7.3 +/- 1.2 vs. 6.6 +/- 1.0 cm/s P = 0.017, S(m): 6.2 +/- 1.0 vs. 5.5 +/- 0.7 cm/s P = 0.002) but only by colour-coded TDI in patients with T2DM (S(m): 5.7 +/- 1.7 vs. 4.9 +/- 1.7 cm/s P = 0.025). Correction for LV length negated the difference between genders in the controls and patients with T2DM (P > 0.05 for all). In controls, LV length was the strongest predictor of S' (beta = 0.393, P = 0.002), whereas height was the strongest predictor of S(m) (beta = 0.394, P = 0.003). In controls, systolic tissue velocities are significantly higher in males compared with females, which may be explained by the increased chamber size of men.
Publisher: Wiley
Date: 28-09-2011
DOI: 10.1111/J.1365-2362.2011.02595.X
Abstract: Central blood pressure (BP) predicts mortality independent of office brachial BP. Whether central BP may be useful to differentiate BP control requires examination and was the first aim of this study. Secondly, we sought to determine the variability in central BP among patients from different categories of BP control [controlled hypertension (CH), masked hypertension (MH), white coat (WCHT) and uncontrolled hypertension (UH)]. We assessed patients with uncomplicated hypertension using measurement of central BP (SphygmoCor 8.1), brachial BP and 24-h ambulatory BP monitoring. BP control was defined according to guidelines using office BP and 24-h BP. Of the 201 patients (63 ± 8 years, 51% men), 67 (33%) were classified as CH 59 (29%) with MH 31 (15%) with WCHT and 44 (22%) with UH. There were no differences in central BP parameters (augmentation pressure, augmentation index, pulse pressure) between patients with CH and MH or between patients with WCHT and UH (P > 0·05 for all). However, there was significant overlap in central systolic BP between BP control categories. For ex le, 27% of patients with normal brachial systolic BP had central systolic BP above age- and gender-specific normal values, including patients from three classifications of BP control (CH: n = 27 MH: n = 22 and WCHT: n = 4). Office central BP alone cannot delineate categories of BP control. However, given the high degree of variability in central BP among patients from different categories of BP control, measurement of central BP may result in significant reclassification of risk related to BP.
Publisher: Oxford University Press (OUP)
Date: 14-02-2013
DOI: 10.1093/AJH/HPT008
Abstract: Although a hypertensive response to exercise (HRE) is associated with cardiac risk and masked hypertension (MHT), its mechanisms and appropriate treatment remain unclear. We investigated spironolactone as a treatment for abnormal vascular and myocardial stiffness in HRE. In this randomized, double-blind, placebo-controlled study of 115 patients (54 ± 9 years, 57% men) with an HRE (≥210/105 mm Hg in men ≥190/105 mm Hg in women) but no prior history of hypertension or myocardial ischemia, MHT prevalence was 40%. Patients were randomized to spironolactone 25mg daily (n = 58) or placebo (n = 57) and underwent evaluation at baseline and 3 months with exercise echocardiography, VO2max, pulse wave velocity (PWV), exercise and central blood pressure (BP), and 24-hour ambulatory BP. Changes in left ventricular mass index (LVMI), Doppler-derived E/em ratio (LV filling pressure), and myocardial strain were assessed. Baseline 24-hour systolic BP (SBP) was 133 ± 10 mm Hg and peak-exercise SBP was 219 ± 16 mm Hg. Peak systolic strain (0.3 ± 3.6% vs. -0.1 ± 3.2, P = 0.56), E/em (-1.1 ± 2.3 vs. -0.6 ± 1.7, P = 0.30), VO(2max) (0.4 ± 4.9 vs. -0.9 ± 4.1 ml/kg/min, P = 0.15), and adjusted PWV did not significantly change with treatment, despite reduction in exercise SBP, 24-hour SBP, and LVMI. The change in exercise E/em was of borderline significance (-0.3 ± 2.4 vs. 0.8 ± 2.8, P = 0.06) and became significant after adjustment for baseline differences (P = 0.01). Patients with higher LVMI significantly increased VO(2max) (1.1 ± 5.6 vs. -2.4 ± 4.4 ml/kg/min, P < 0.05) and reduced exercise E/e(m) (-0.7 ± 2.7 vs. 1.9 ± 2.8, P < 0.05). In HRE patients without previous hypertension, short-term spironolactone reduced exercise BP, 24-hour ambulatory BP, LVMI, and E/e(m) but did not significantly alter exercise capacity or myocardial strain.
Publisher: Oxford University Press (OUP)
Date: 30-01-2017
Publisher: Springer Science and Business Media LLC
Date: 2018
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 07-2020
DOI: 10.1161/HYPERTENSIONAHA.120.14916
Abstract: Numerous devices purport to measure central (aortic) blood pressure (BP) as distinct from conventional brachial BP. This validation study aimed to determine the accuracy of the Sphygmocor Xcel cuff device (AtCor Medical, CardieX, Sydney, Australia) for measuring central BP. 296 patients (mean age 61±12 years) undergoing coronary angiography had simultaneous measurement of invasive central BP and noninvasive cuff-derived central BP using the Xcel cuff device (total n=558 in idual comparisons). A subs le (n=151) also had invasive brachial BP measured. Methods were undertaken according to the Artery Society recommendations, and several calibration techniques to derive central systolic BP (SBP) were examined. Minimum acceptable error was ≤5±≤8 mm Hg. Central SBP was significantly underestimated, and with wide variability, when using the default calibration of brachial-cuff SBP and diastolic BP (DBP mean difference±SD, −7.7±11.0 mm Hg). Similar variability was observed using other calibration methods (cuff 33% form-factor mean arterial pressure and DBP, −4.4±11.5 mm Hg cuff 40% form-factor mean arterial pressure and DBP, 4.7±11.9 mm Hg cuff oscillometric mean arterial pressure and DBP, −18.2±12.1 mm Hg). Only calibration with invasive central integrated mean arterial pressure and DBP was within minimal acceptable error (3.3±7.5 mm Hg). The difference between brachial-cuff SBP and invasive central SBP was 3.3±10.7 mm Hg. A subs le analysis to determine the accuracy of central-to-brachial SBP lification showed this to be overestimated by the Xcel cuff device (mean difference 4.3±9.1 mm Hg, P =0.02). Irrespective of cuff calibration technique, the Sphygmocor Xcel cuff device does not meet the Artery Society accuracy criteria for noninvasive measurement of central BP.
Publisher: Oxford University Press (OUP)
Date: 02-06-2022
Abstract: Most international guidelines recommend that repeat blood pressure (BP) readings are required for BP classification. Two international guidelines erge from this by recommending that no further BP measurements are required if the first clinic BP is below a hypertension threshold. The extent to which within-visit BP variability patterns change over time, and whether this could impact BP classification is unknown. We sought to examine this. Data were from the Cardiovascular Risk in Young Finns Study, a prospective cohort study. Up to 2799 participants were followed from childhood (9–15 years) to adulthood (18–49 years) over up to six visits. Patterns of within-visit systolic BP (SBP) variability were defined as no-change, decrease, increase between consecutive readings (with 5 mmHg change thresholds). Classification of SBP (normal, high-normal, hypertension) using the first reading was compared with repeat readings. On average, SBP decreased with subsequent measures, but with major in idual variability (no-change: 56.9–62.7% decrease: 24.1–31.6% increase: 11.5–16.8%). Patterns of SBP variability were broadly similar from childhood to adulthood, with the highest prevalence of an increase among participants categorized with normal SBP (12.6–20.3%). The highest prevalence of SBP reclassification occurred among participants with hypertension (28.9–45.3% reclassified as normal or high-normal). The prevalence of reclassification increased with the magnitude of change between readings. There is a major in idual variation of within-visit SBP change in childhood and adulthood and can influence BP classification. This highlights the importance of consistency among guidelines recommending that repeat BP measurements are needed for BP classification.
Publisher: Springer Science and Business Media LLC
Date: 07-2022
DOI: 10.1038/S41371-022-00718-5
Abstract: Clinically validated, automated arm-cuff blood pressure measuring devices (BPMDs) are recommended for BP measurement. However, most BPMDs available for purchase by consumers globally are not properly validated. This is a problem because non-validated BPMDs are less accurate and precise than validated ones, and therefore if used clinically could lead to misdiagnosis and mismanagement of BP. In response to this problem, several validated device lists have been developed, which can be used by clinicians and consumers to identify devices that have passed clinical validation testing. The purpose of this review is to describe the resources that are available for finding validated BPMDs in different world regions, to identify the differences between validated device lists, and describe current gaps and challenges. How to use validated BPMDs properly is also summarised.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 08-04-2021
Publisher: Elsevier BV
Date: 11-2016
Publisher: Oxford University Press (OUP)
Date: 06-11-2017
DOI: 10.1093/AJH/HPX180
Abstract: Automated office blood pressure (AOBP) involving repeated, unobserved blood pressure (BP) readings during one clinic visit is recommended for in-office diagnosis and assessment of hypertension. However, the optimal AOBP protocol to determine BP control in the least amount of time with the fewest BP readings is yet to be determined and was the aim of this study. One hundred and eighty-nine patients (mean age 62.8 ± 12.1 years 50.3% female) with treated hypertension referred to specialist clinics at 2 sites underwent AOBP in a quiet room alone. Eight BP measurements were taken starting immediately after sitting and then at 2-minute intervals (15 minutes total). The optimal AOBP protocol was defined by the smallest mean difference and highest intraclass correlation coefficient (ICC) compared with daytime ambulatory BP (ABP). The same BP device (Mobil-o-graph, IEM) was used for both AOBP and daytime ABP. Average 15-minute AOBP and daytime ABP were 134 ± 22/82 ± 13 and 137 ± 17/83 ± 11 mm Hg, respectively. The optimal AOBP protocol was derived within a total duration of 6 minutes from the average of 2 measures started after 2 and 4 minutes of seated rest (systolic BP: mean difference (95% confidence interval) 0.004(−2.21, 2.21) mm Hg, P = 1.0 ICC = 0.81 diastolic BP: mean difference 0.37(−0.90, 1.63) mm Hg, P = 0.57 ICC = 0.86). AOBP measures taken after 8 minutes tended to underestimate daytime ABP (whether as a single BP or the average of more than 1 BP reading). Only 2 AOBP readings taken over 6 minutes (excluding an initial reading immediately after sitting) may be needed to be comparable with daytime ABP.
Publisher: Springer Science and Business Media LLC
Date: 2016
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 09-2015
Publisher: Wiley
Date: 25-11-2019
DOI: 10.1111/JCH.13741
Publisher: Wiley
Date: 04-06-2004
Publisher: Elsevier BV
Date: 2023
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 06-2017
Publisher: American Diabetes Association
Date: 04-2005
Publisher: Oxford University Press (OUP)
Date: 27-12-2013
DOI: 10.1093/AJH/HPS053
Abstract: The prognostic relevance of a hypertensive response to exercise (HRE) is ill-defined in in iduals undergoing exercise stress testing. The study described here was intended to provide a systematic review and meta-analysis of published literature to determine the value of exercise-related blood pressure (BP) (independent of office BP) for predicting cardiovascular (CV) events and mortality. Online databases were searched for published longitudinal studies reporting exercise-related BP and CV events and mortality rates. We identified for review 12 longitudinal studies with a total of 46,314 in iduals without significant coronary artery disease, with total CV event and mortality rates recorded over a mean follow-up of 15.2±4.0 years. After adjustment for age, office BP, and CV risk factors, an HRE at moderate exercise intensity carried a 36% greater rate of CV events and mortality (95% CI, 1.02-1.83, P = 0.039) than that of subjects without an HRE. Additionally, each 10mm Hg increase in systolic BP during exercise at moderate intensity was accompanied by a 4% increase in CV events and mortality, independent of office BP, age, or CV risk factors (95% CI, 1.01-1.07, P = 0.02). Systolic BP at maximal workload was not significantly associated with the outcome of an increased rate of CV, whether analyzed as a categorical (HR=1.49, 95% CI, 0.90-2.46, P = 0.12) or a continuous (HR=1.01, 95% CI, 0.98-1.04, P = 0.53) variable. An HRE at moderate exercise intensity during exercise stress testing is an independent risk factor for CV events and mortality. This highlights the need to determine underlying pathophysiological mechanisms of exercise-induced hypertension.
Publisher: Springer Science and Business Media LLC
Date: 20-02-2023
Publisher: Springer Science and Business Media LLC
Date: 27-05-2010
DOI: 10.1038/JHH.2010.53
Abstract: An exaggerated blood pressure (BP) response to exercise predicts future cardiovascular risk. The mechanisms underlying exercise-induced hypertension remain unclear, although endothelial dysfunction and elevated arterial stiffness may contribute. Given the association between reductions in nitric oxide (NO) and vascular dysfunction, we sought to determine whether acute inhibition of NO synthase with N(G)-monomethyl-L-arginine (L-NMMA) would lead to exaggerated BP responses to maximal exercise and attenuate exercise-induced reductions in arterial stiffness. In 10 healthy subjects (31±5 years), BP and heart rate (HR) were measured before, during and after an incremental cycling exercise test to determine maximal oxygen consumption (VO(2)max). Trials were performed with placebo (saline) or intravenous infusion of L-NMMA on separate days in a randomized, double-blind, crossover design. Central (aortic) and peripheral (femoral) arterial stiffness were assessed using pulse wave velocity (PWV). BP was increased with L-NMMA at rest and during sub-maximal exercise, but not at maximal exercise (mean BP 117±5 vs 118±8 mm Hg, saline vs L-NMMA, P>0.05). Furthermore, L-NMMA had no influence on exercising HR or VO(2)max (P<0.05). Notably, aortic PWV was similarly increased after exercise with either saline or L-NMMA (P<0.05), whereas postexercise decreases in femoral PWV were attenuated with L-NMMA (P<0.05). Our findings suggest that NO is an important contributor to reductions in femoral artery stiffness after maximal exercise in healthy in iduals. Furthermore, acute pharmacological inhibition of NO synthase causes augmented BP responses to sub-maximal exercise, but does not lead to exaggerated BP responses to maximal exercise or reduce maximal oxygen consumption.
Publisher: Pan American Health Organization
Date: 12-03-2020
Abstract: Objective. To characterize the design of excise taxes on sugar-sweetened beverages (SSBs) in Latin America and the Caribbean and assess opportunities to increase their impact on SSB consumption and health. Methods. A comprehensive search and review of the legislation in effect as of March 2019, collected through existing Pan American Health Organization and World Health Organization monitoring tools, secondary sources, and surveying ministries of finance. The analysis focused on the type of products taxed, and the structure and base of these excise taxes. Results. Out of the 33 countries analyzed, 21 apply excise taxes on SSBs. Seven countries also apply excise taxes on bottled water and at least four include sugar-sweetened milk drinks. Ten of these excise taxes are ad valorem with some tax bases set early in the value chain, seven are amount-specific, and four have either a combined or mixed structure. Three countries apply excise taxes based on sugar concentration. Conclusions. While the number of countries applying excise taxes on SSBs is promising, there is great heterogeneity in design in terms of structure, tax base, and products taxed. Existing excise taxes could be further leveraged to improve their impact on SSB consumption and health by including all categories of SSBs, excluding bottled water, and relying more on amount-specific taxes regularly adjusted for inflation and possibly based on sugar concentration. All countries would benefit from additional guidance. Future research should aim to address this gap.
Publisher: Springer Science and Business Media LLC
Date: 23-10-2014
Publisher: Oxford University Press (OUP)
Date: 16-04-2020
Abstract: Absolute cardiovascular disease (CVD) risk assessment is recommended for primary prevention of CVD, yet uptake in general practice is limited. Cholesterol requests at pathology services provide an opportunity to improve uptake by integrating absolute CVD risk assessment with this service. This study aimed to assess the feasibility of such an additional service. Two-hundred and ninety-nine patients (45–74 years) referred to pathology services for blood cholesterol had measurement of all variables required to determine absolute CVD risk according to Framingham calculator (blood pressure, age, sex, smoking and diabetes status via self-report). Data were recorded via computer-based application. The absolute risk score was communicated via the report sent to the referring medical practitioner as per usual practice. Evaluation questionnaires were completed immediately post visit and at 1-, 3- and 6-month follow-up via telephone (n = 262). Absolute CVD risk reports were issued for 90% of patients. Most patients (95%) reported that the length of time for the pathology service assessment was acceptable, and 91% that the self-directed computer-based application was easy to use. Seventy-eight per cent reported a preference for pathology services to conduct absolute CVD risk assessment. Only 2% preferred a medical practitioner. Of follow-up patients, 202 (75%) had a consultation with a medical practitioner, during which, aspects of CVD risk prevention were discussed (cholesterol and blood pressure 74% and 69% of the time, respectively). Measurement of absolute CVD risk in pathology services is feasible, highly acceptable among middle-to-older adults and may increase uptake of guideline-directed care in general practice.
Publisher: Oxford University Press (OUP)
Date: 05-07-2005
DOI: 10.1093/NDT/GFH875
Abstract: Transplant recipients have elevated oxidative stress, which has prompted suggestions that supplementary antioxidants may be beneficial. However, only a small number of clinical trials have investigated antioxidant supplementation in transplant recipients, with very few data on their effects on patients' immunosuppressive therapy. A randomized placebo-controlled single-blind crossover trial was conducted in 10 renal transplant recipients (RTRs) taking cyclosporin A (CsA) as part of their immunosuppressive therapy. Each phase of the trial lasted 6 months, with a 6 month wash-out period in between. During one of the phases, patients consumed a tablet twice per day which delivered 400 IU/day of vitamin E, 500 mg/day of vitamin C and 6 mg/day of beta-carotene. During antioxidant supplementation, there was no change in CsA dose. Antioxidant supplementation resulted in a significant decrease (P<0.05) in blood trough CsA by 24% (mean+/-SD, pre- 127.3+/-38.9, post- 97.2+/-30.7 microg/ml) compared with no change while taking the placebo (pre- 132.2+/-50.6, post- 138.6+/-56.0 microg/ml). The glomerular filtration rate was significantly (P 0.05) in markers of oxidative stress (malondialdehyde, susceptibility of plasma to oxidation) or plasma antioxidant enzymes. In CsA-treated RTRs, antioxidant supplementation decreased blood CsA, which may affect adequacy of immunosuppression.
Publisher: Oxford University Press (OUP)
Date: 21-12-2017
Abstract: People with exaggerated exercise blood pressure (BP) have adverse cardiovascular outcomes. Mechanisms are unknown but could be explained through impaired neural baroreflex sensitivity (BRS) and/or large artery stiffness. This study aimed to determine the associations of carotid BRS and carotid stiffness with exaggerated exercise BP. Blood pressure was recorded at rest and following an exercise step-test among 8976 adults aged 50 to 75 years from the Paris Prospective Study III. Resting carotid BRS (low frequency gain, from carotid distension rate, and heart rate) and stiffness were measured by high-precision echotracking. A systolic BP threshold of ≥ 150 mmHg defined exaggerated exercise BP and ≥140/90 mmHg defined resting hypertension (±antihypertensive treatment). Participants with exaggerated exercise BP had significantly lower BRS [median (Q1 Q3) 0.10 (0.06 0.16) vs. 0.12 (0.08 0.19) (ms2/mm) 2×108 P < 0.001] but higher stiffness [mean ± standard deviation (SD) 7.34 ± 1.37 vs. 6.76 ± 1.25 m/s P < 0.001) compared to those with non-exaggerated exercise BP. However, only lower BRS (per 1SD decrement) was associated with exaggerated exercise BP among people without hypertension at rest {specifically among those with optimal BP odds ratio (OR) 1.16 [95% confidence intervals (95% CI) 1.01 1.33], P = 0.04 and high-normal BP OR, 1.19 (95% CI 1.07 1.32), P = 0.001} after adjustment for age, sex, body mass index, smoking, alcohol, total cholesterol, high-density lipoprotein cholesterol, resting heart rate, and antihypertensive medications. Impaired BRS, but not carotid stiffness, is independently associated with exaggerated exercise BP even among those with well controlled resting BP. This indicates a potential pathway from depressed neural baroreflex function to abnormal exercise BP and clinical outcomes.
Publisher: Portland Press Ltd.
Date: 02-02-2009
DOI: 10.1042/CS20080096
Abstract: In the present study, we investigated the effects of basal and intra-arterial infusion of bradykinin on unstressed forearm vascular volume (a measure of venous tone) and blood flow in healthy volunteers (n=20) and in chronic heart failure patients treated with ACEIs [ACE (angiotensin-converting enzyme) inhibitors] (n=16) and ARBs (angiotensin receptor blockers) (n=14). We used radionuclide plethysmography to examine the effects of bradykinin and of the bradykinin antagonists B9340 [B1 (type 1)/B2 (type 2) receptor antagonist] and HOE140 (B2 antagonist). Bradykinin infusion increased unstressed forearm vascular volume in a similar dose-dependent manner in healthy volunteers and ARB-treated CHF patients (healthy volunteers maximum 12.3±2.1%, P& .001 compared with baseline ARB-treated CHF patients maximum 9.3±3.3%, P& .05 compared with baseline P=not significant for difference between groups), but the increase in unstressed volume in ACEI-treated CHF patients was higher (maximum 28.8±7.8%, P& .001 compared with baseline P& .05 for the difference between groups). In contrast, while the increase in blood flow in healthy volunteers (maximum 362±9%, P& .001) and in ACEI-treated CHF patients (maximum 376±12%, P& .001) was similar (P=not significant for the difference between groups), the increase in ARB-treated CHF patients was less (maximum 335±7%, P& .001 P& .05 for the difference between groups). Infusion of each receptor antagonist alone similarly reduced basal unstressed volume and blood flow in ACEI-treated CHF patients, but not in healthy volunteers or ARB-treated CHF patients. In conclusion, bradykinin does not contribute to basal venous tone in health, but in ACEI-treated chronic heart failure it does. In ARB-treated heart failure, venous responses to bradykinin are preserved but arterial responses are reduced compared with healthy controls. Bradykinin-mediated vascular responses in both health and heart failure are mediated by the B2, rather than the B1, receptor.
Publisher: Springer Science and Business Media LLC
Date: 16-10-2017
Publisher: Public Library of Science (PLoS)
Date: 11-11-2015
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 11-2009
DOI: 10.1161/HYPERTENSIONAHA.109.135525
Abstract: Blood (or plasma) rheology is related to cardiovascular risk. Mechanisms of this association are unclear but may be partially related to impaired left ventricular (LV) function and increased central blood pressure (BP) during light activity. This study aimed to test these hypotheses. Twenty patients (14 men aged 61±12 years) with polycythemia rubra vera (n=16) or hemochromatosis (n=4) were studied at rest and during exercise at ≈50% of maximal heart rate before and after venesection (500 mL volume replaced with saline) to elicit an acute decrease in plasma viscosity at stable BP. Controls (n=20) underwent the same protocol with 25-mL venesection. Central BP and augmentation index were determined by tonometry. Resting LV systolic (peak longitudinal systolic strain rate and strain) and diastolic functions were determined by tissue-Doppler echocardiography. Venesection with blood volume replacement decreased viscosity (1.46±0.10 to 1.41±0.11 centipoise), protein, and hemoglobin ( P .05 for all) and increased strain rate and strain ( P .001 for both) in patients but not in controls ( P .10 for all). There was no change in LV diastolic function ( P .12 for all). Exercise augmentation index in patients was reduced after venesection (24±12% to 17±9% P =0.001) despite no significant change in other BP variables. Hemodynamics (resting or exercise) were not significantly changed in controls. Exercise central systolic BP correlated with triglycerides ( r =0.59 P .001). However, neither exercise hemodynamic changes nor LV functional changes correlated with any biochemical changes after venesection ( P .05). We conclude that an acute change in blood rheology improves ventricular-vascular interaction by enhanced LV systolic function and reduced light-exercise central BP.
Publisher: Springer Science and Business Media LLC
Date: 24-03-2022
DOI: 10.1038/S41371-022-00673-1
Abstract: With the rising prevalence of hypertension, especially in Africa, understanding the dynamics of socio-demographic and lifestyle factors is key in managing hypertension. To address existing gaps in evidence of these factors, this study was carried out. A cross-sectional survey using a modified WHO STEPS questionnaire was conducted among 3782 adult Nigerians selected from an urban and a rural community in one state in each of the six Nigerian regions. Among participants, 56.3% were women, 65.8% were married, 52.5% resided in rural areas, and 33.9% had tertiary education. Mean ages (SD) were 53.1 ± 13.6 years and 39.2 ± 15.0 years among hypertensive persons and their normotensive counterparts respectively. On lifestyle, 30.7% had low physical activity, 4.1% consumed tobacco currently, and 35.4% consumed alcohol currently. In comparison to unmarried status, being married (OR = 1.88, 95% CI: 1.41–2.50) or widowed (OR = 1.57, 95% CI: 1.05–2.36) was significantly associated with hypertension, compared with never married. Compared with no formal education, primary (OR = 1.44, 95% CI: 1.12–1.85), secondary (OR = 1.37, 95% CI: 1.04–1.81), and tertiary education (OR = 2.02, 95% CI: 1.57–2.60) were associated with hypertension. Low physical activity (OR = 1.23, 95% CI: 1.05–1.42), alcohol consumption, (OR = 1.18, 95% CI: 1.02–1.37), and unemployment status (OR = 1.42 95% CI: 1.07–1.88) were also associated with hypertension. Our study indicates an association of socio-demographic and lifestyle factors with hypertension, hence, there is a need for counselling, health education and policy formulation and implementation targeting these factors to prevent and control hypertension.
Publisher: Wiley
Date: 17-09-2008
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 09-2017
Publisher: SAGE Publications
Date: 07-04-2016
Abstract: Blood pressure variability is associated with macrovascular complications and stroke, but its association with the microcirculation in type II diabetes has not been assessed. This study aimed to determine the relationship between blood pressure variability indices and retinal arteriolar diameter in non-diabetic and type II diabetes participants. Digitized retinal images were analysed to quantify arteriolar diameters in 35 non-diabetic (aged 52 ± 11 years 49% male) and 28 type II diabetes (aged 61 ± 9 years 50% male) participants. Blood pressure variability was derived from 24-h ambulatory blood pressure. Arteriolar diameter was positively associated with daytime rate of systolic blood pressure variation ( p = 0.04) among type II diabetes participants and negatively among non-diabetics ( p = 0.008 interaction p = 0.001). This finding was maintained after adjusting for age, sex, body mass index and mean daytime systolic blood pressure. These findings suggest that the blood pressure variability–related mechanisms underlying retinal vascular disease may differ between people with and without type II diabetes.
Publisher: Elsevier BV
Date: 10-2016
DOI: 10.1016/J.KINT.2016.06.039
Abstract: Carlsen et al. demonstrated that the estimation of central blood pressure from peripheral tonometry does not work properly in patients with chronic kidney disease. We explore here the implications of this finding, first by considering the technical conditions for validating central BP monitors, then by discussing the possible causes for discrepancies between chronic kidney disease patients and usual study populations. Lastly, we review the merits and limits of the work by Carlsen et al.
Publisher: Elsevier BV
Date: 11-2017
DOI: 10.1016/J.CCT.2017.08.010
Abstract: High blood pressure (BP) is the most common modifiable cause of death from cardiovascular disease. Lowering BP with medication improves patient outcomes, but even in populations with normal upper arm (brachial) BP there remains considerable residual risk for cardiovascular disease and this may be due to persistently elevated central BP. There has never been a trial to determine the value of targeted central BP lowering among patients with hypertension, and this was the aim of this study. This is a multi-centre, randomized, open-label, blinded endpoint trial among 308 patients treated for uncomplicated hypertension with controlled brachial BP (<140/90mmHg) but elevated central BP (≥0.5SD above age- and sex-specific normal values). Baseline recruitment has been completed. Participants were randomized to intervention with spironolactone (25mg/d) or usual care and are being followed over 24months, with the primary outcome being left ventricular mass index (using cardiac magnetic resonance imaging). Brachial and central BP will be measured in the clinic, at home over 7-days and by 24-h ambulatory monitoring. Aortic stiffness will be assessed by carotid-to-femoral pulse wave velocity. Primary (intention to treat) analysis will determine the role of central versus brachial BP for predicting changes in left ventricular mass index. Compared with control, intervention is expected to significantly lower left ventricular mass index, and this effect is expected to be independently correlated with central BP lowering. These findings would support the concept of central BP as an important therapeutic target in hypertension management. Results are expected in 2018.
Publisher: The Endocrine Society
Date: 09-2005
DOI: 10.1210/JC.2005-0681
Abstract: To explore whether aldosterone excess can induce adverse cardiovascular effects independently of effects on blood pressure (BP), we sought evidence of disturbed cardiovascular structure or function in normotensive in iduals with primary aldosteronism. Eight normotensive subjects with genetically proven familial hyperaldosteronism type I (FH-I) were compared with 24 age- and sex-matched normotensive controls in terms of BP, biochemical parameters, pulse wave velocity, and echocardiographic characteristics. Subjects with FH-I demonstrated higher serum aldosterone levels and aldosterone/renin ratios than controls, as expected. Despite having similar 24-h ambulatory BPs, subjects with FH-I demonstrated evidence of concentric remodeling with greater septal (mean +/- sd, 9.4 +/- 1.1 vs. 7.9 +/- 0.9 mm P < 0.001), posterior wall (9.2 +/- 1.7 vs. 7.7 +/- 1.0 mm P < 0.01), and relative wall (0.29 +/- 0.03 vs. 0.24 +/- 0.02 P < 0.001) thicknesses, and lower mitral early peak velocities (0.74 +/- 0.10 vs. 0.90 +/- 0.16 m/sec P < 0.05), ratios of early to late peak diastolic transmitral flow velocity (1.56 +/- 0.24 vs. 2.06 +/- 0.41 P < 0.01), and myocardial early peak velocities (8.3 +/- 1.8 vs. 10.3 +/- 2.6 cm/sec P < 0.05). There were no significant differences in pulse wave velocity or left ventricular ejection fraction, long axis strain rate, peak systolic strain, cyclic variation of integrated backscatter, or posterior wall calibrated integrated backscatter. Aldosterone excess is associated with increased left ventricular wall thicknesses and reduced diastolic function, even in the absence of hypertension.
Publisher: Wiley
Date: 22-10-2019
DOI: 10.1111/JCH.13717
Publisher: Wiley
Date: 25-11-2005
DOI: 10.1111/J.1365-2362.2005.01578.X
Abstract: Brachial blood pressure predicts cardiovascular outcome at rest and during exercise. However, because of pulse pressure lification, there is a marked difference between brachial pressure and central (aortic) pressure. Although central pressure is likely to have greater clinical importance, very little data exist regarding the central haemodynamic response to exercise. The aim of the present study was to determine the central and peripheral haemodynamic response to incremental aerobic exercise. Twelve healthy men aged 31 +/- 1 years (mean +/- SEM) exercised at 50%, 60%, 70% and 80% of their maximal heart rate (HRmax) on a bicycle ergometer. Central blood pressure and estimated aortic pulse wave velocity, assessed by timing of the reflected wave (T(R)), were obtained noninvasively using pulse wave analysis. Pulse pressure lification was defined as the ratio of peripheral to central pulse pressure and, to assess the influence of wave reflection on lification, the ratio of peripheral pulse pressure to nonaugmented central pulse pressure (PPP : CDBP-P1) was also calculated. During exercise, there was a significant, intensity-related, increase in mean arterial pressure and heart rate (P < 0.001). There was also a significant increase in pulse pressure lification and in PPP : CDBP-P(1) (P < 0.001), but both were independent of exercise intensity. Estimated aortic pulse wave velocity increased during exercise (P < 0.001), indicating increased aortic stiffness. There was also a positive association between aortic pulse wave velocity and mean arterial pressure (r = 0.54 P < 0.001). Exercise significantly increases pulse pressure lification and estimated aortic stiffness.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 06-2006
DOI: 10.1161/01.HYP.0000223013.60612.72
Abstract: Exercise brachial blood pressure (BP) predicts mortality, but because of wave reflection, central (ascending aortic) pressure differs from brachial pressure. Exercise central BP may be clinically important, and a noninvasive means to derive it would be useful. The purpose of this study was to test the validity of a noninvasive technique to derive exercise central BP. Ascending aortic pressure waveforms were recorded using a micromanometer-tipped 6F Millar catheter in 30 patients (56±9 years 21 men) undergoing diagnostic coronary angiography. Simultaneous recordings of the derived central pressure waveform were acquired using servocontrolled radial tonometry at rest and during supine cycling. Pulse wave analysis of the direct and derived pressure signals was performed offline (SphygmoCor 7.01). From rest to exercise, mean arterial pressure and heart rate were increased by 20±10 mm Hg and 15±7 bpm, respectively, and central systolic BP ranged from 77 to 229 mm Hg. There was good agreement and high correlation between invasive and noninvasive techniques with a mean difference (±SD) for central systolic BP of −1.3±3.2 mm Hg at rest and −4.7±3.3 mm Hg at peak exercise (for both r =0.995 P .001). Conversely, systolic BP was significantly higher peripherally than centrally at rest (155±33 versus 138±32 mm Hg mean difference, −16.3±9.4 mm Hg) and during exercise (180±34 versus 164±33 mm Hg mean difference, −15.5±10.4 mm Hg for both P .001). True myocardial afterload is not reliably estimated by peripheral systolic BP. Radial tonometry and pulse wave analysis is an accurate technique for the noninvasive determination of central BP at rest and during exercise.
Publisher: Elsevier BV
Date: 10-2010
Publisher: Elsevier
Date: 2022
Publisher: Springer Science and Business Media LLC
Date: 06-08-2012
Abstract: Osteoarthritis (OA) is a common health issue worldwide in the aging population who are also commonly deficient in vitamin D. Our previous study suggested that higher serum 25-(OH)D levels were associated with reduced knee cartilage loss, implying that vitamin D supplementation may prevent the progression of knee OA. The aim of the VItamin D Effects on OA (VIDEO) study is to compare, over a 2- year period, the effects of vitamin D supplementation versus placebo on knee structural changes, knee pain, and lower limb muscle strength in patients with symptomatic knee OA. Randomised, placebo-controlled, and double-blind clinical trial aiming to recruit 400 subjects (200 from Tasmania and 200 from Victoria) with both symptomatic knee OA and vitamin D deficiency (serum [25-(OH)D] level of .5 nmol/liter and nmol/liter). Participants will be randomly allocated to vitamin D supplementation (50,000 IU compounded vitamin D 3 capsule monthly) or identical inert placebo group for 2 years. The primary endpoint is loss of knee cartilage volume measured by magnetic resonance imaging (MRI) and Western Ontario and McMaster Universities Index of OA (WOMAC) knee pain score. The secondary endpoints will be other knee structural changes, and lower limb muscle strength. Several other outcome measures including core muscle images and central blood pressure will be recorded. Linear and logistic regression will be used to compare changes between groups using univariable and multivariable modeling analyses. Both intention to treat and per protocol analyses will be utilized. The trial is designed to test if vitamin D supplementation will reduce loss of knee cartilage volume, prevent the progression of other knee structural abnormalities, reduce knee pain and strengthen lower limb muscle strength, thus modify disease progression in knee OA. ClinicalTrials.gov identifier: NCT01176344 Australian New Zealand Clinical Trials Registry: ACTRN12610000495022
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 12-2017
Publisher: American Physiological Society
Date: 10-2015
DOI: 10.1152/AJPHEART.00317.2015
Abstract: Central augmentation pressure (AP) and index (AIx) predict cardiovascular events and mortality, but underlying physiological mechanisms remain disputed. While traditionally believed to relate to wave reflections arising from proximal arterial impedance (and stiffness) mismatching, recent evidence suggests aortic reservoir function may be a more dominant contributor to AP and AIx. Our aim was therefore to determine relationships among aortic-brachial stiffness mismatching, AP, AIx, aortic reservoir function, and end-organ disease. Aortic (aPWV) and brachial (bPWV) pulse wave velocity were measured in 359 in iduals (aged 61 ± 9, 49% male). Central AP, AIx, and aortic reservoir indexes were derived from radial tonometry. Participants were stratified by positive (bPWV aPWV), negligible (bPWV ≈ aPWV), or negative stiffness mismatch (bPWV aPWV). Left-ventricular mass index (LVMI) was measured by two-dimensional-echocardiography. Central AP and AIx were higher with negative stiffness mismatch vs. negligible or positive stiffness mismatch (11 ± 6 vs. 10 ± 6 vs. 8 ± 6 mmHg, P 0.001 and 24 ± 10 vs. 24 ± 11 vs. 21 ± 13%, P = 0.042). Stiffness mismatch (bPWV-aPWV) was negatively associated with AP ( r = −0.18, P = 0.001) but not AIx ( r = −0.06, P = 0.27). Aortic reservoir pressure strongly correlated to AP ( r = 0.81, P 0.001) and AIx ( r = 0.62, P 0.001) independent of age, sex, heart rate, mean arterial pressure, and height (standardized β = 0.61 and 0.12, P ≤ 0.001). Aortic reservoir pressure independently predicted abnormal LVMI (β = 0.13, P = 0.024). Positive aortic-brachial stiffness mismatch does not result in higher AP or AIx. Aortic reservoir function, rather than discrete wave reflection from proximal arterial stiffness mismatching, provides a better model description of AP and AIx and also has clinical relevance as evidenced by an independent association of aortic reservoir pressure with LVMI.
Publisher: Wiley
Date: 03-09-2020
DOI: 10.1111/JCH.14017
Publisher: Elsevier BV
Date: 09-2018
DOI: 10.1016/J.JASH.2018.06.015
Abstract: A single clinic measurement of blood pressure (BP) may be common in low- and middle-income countries because of limited medical resources. This study aimed to examine the potential misclassification error when only one BP measurement is used. Participants (n = 14,706, 53.5% females) aged 25-64 years were selected by multistage stratified cluster s ling from eight provinces, each representing one of the eight geographical regions of Vietnam. Measurements were made using the World Health Organization STEPS protocols. Data were analyzed using complex survey methods. For systolic BP, 62.7% had a higher first reading whereas 30.0% had a lower first reading, and 27.3% had a reduction of at least 5 mmHg whereas 9.6% had an increase of at least 5 mmHg. Irrespective of direction of change, increased variability in BP was associated with greater age, urban living, greater body size and fatness, reduced physical activity levels, elevated glucose, and raised total cholesterol. These measurement variations would lead to substantial misclassification in diagnosis of hypertension based on a single reading because almost 20% of subjects would receive a different diagnosis based on the mean of two readings.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 04-2017
Publisher: The International Society of Hypertension
Date: 06-2020
DOI: 10.30824/2006-17
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 07-2014
DOI: 10.1161/ATVBAHA.114.303573
Abstract: Aortic reservoir pressure indices independently predict cardiovascular events and mortality. Despite this, there has never been a study in humans to determine whether the theoretical principles of the mathematically derived aortic reservoir pressure (RP derived ) and excess pressure (XP derived ) model have a real physiological basis. This study aimed to directly measure the aortic reservoir (AR direct by cyclic change in aortic volume) and determine its relationship with RP derived , XP derived , and aortic blood pressure (BP). Ascending aortic BP and Doppler flow velocity were recorded via intra-arterial wire in 10 men (aged 62±12 years) during coronary artery bypass surgery. Simultaneous ascending aortic transesophageal echocardiography was used to measure AR direct . Published mathematical formulae were used to determine RP derived and XP derived . AR direct was strongly and linearly related to RP derived during systole ( r =0.988 P .001) and diastole ( r =0.985 P .001). Peak cross-correlation ( r =0.98) occurred at a phase lag of 0.004 s into the cardiac cycle, suggesting close temporal agreement between waveforms. The relationship between aortic BP and AR direct was qualitatively similar to the cyclic relationship between aortic BP and RP derived , with peak cross-correlations occurring at identical phase lags (AR direct versus aortic BP, r =0.96 at 0.06 s RP derived versus aortic BP, r =0.98 at 0.06 s). RP derived is highly correlated with changes in proximal aortic volume, consistent with its physiological interpretation as corresponding to the instantaneous volume of blood stored in the aorta. Thus, aortic reservoir pressure should be considered in the interpretation of the central BP waveform.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 02-2019
Publisher: Mary Ann Liebert Inc
Date: 10-2023
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 09-2012
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 19-10-2022
DOI: 10.1249/JES.0000000000000276
Abstract: We propose that for correct clinical interpretation of exaggerated exercise blood pressure (EEBP), both cardiorespiratory fitness and exercise workload must be considered. A key recommendation toward achieving the correct clinical interpretation of EEBP is that exercise BP should be measured during submaximal exercise with a fixed external workload.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 07-2013
DOI: 10.1161/HYPERTENSIONAHA.111.00584
Abstract: Exercise hypertension independently predicts cardiovascular mortality, although little is known about exercise central hemodynamics. This study aimed to determine the contribution of arterial wave travel and aortic reservoir characteristics to central blood pressure (BP) during exercise. We hypothesized that exercise central BP would be principally related to forward wave travel and aortic reservoir function. After routine diagnostic coronary angiography, invasive pressure and flow velocity were recorded in the ascending aorta via sensor-tipped intra-arterial wires in 10 participants (age, 55±10 years 70% men) free of coronary artery disease with normal left ventricular function. Measures were recorded at baseline and during supine cycle ergometry. Using wave intensity analysis, dominant wave types throughout the cardiac cycle were identified (forward and backward, compression, and decompression), and aortic reservoir and excess pressure were calculated. Central systolic BP increased significantly with exercise (Δ=19±12 mm Hg P .001). This was associated with increases in systolic forward compression waves (Δ=12×10 6 ±17×10 6 W·m −2 ·s −1 P =0.045) and forward decompression waves in late systole (Δ=9×10 6 ±6×10 6 W·m −2 ·s −1 P .001). Despite significant augmentation in BP (Δ=9±6 mm Hg P =0.002), reflected waves did not increase in magnitude (Δ=−1×10 6 ±3×10 6 W·m −2 ·s −1 P =0.2). Excess pressure rose significantly with exercise (Δ=16±9 mm Hg P .001), and reservoir pressure integral fell (Δ=−5×10 5 ±5×10 5 Pa·s P =0.010). Change in reflection coefficient negatively correlated with change in central systolic BP ( r =−0.68 P =0.03). We conclude that elevation of exercise central BP is principally because of increases in aortic forward traveling waves generated by left ventricular ejection. These findings have relevance to understanding central BP waveform morphology and pathophysiology of exercise hypertension.
Publisher: Oxford University Press (OUP)
Date: 13-04-2016
DOI: 10.1093/AJH/HPW037
Abstract: The average of multiple blood pressure (BP) readings (mean BP) independently predicts target organ damage (TOD). Observational studies have also shown an independent relationship between BP variability (BPV) and TOD, but there is limited longitudinal data. This study aimed to determine the effects of changes in mean BP levels compared with BPV on left ventricular mass index (LVMI) and aortic pulse wave velocity (aPWV). Mean BP levels (research-protocol clinic BP (clinic BP), 24-hour ambulatory BP, and 7-day home BP) and BPV were assessed in 286 patients with uncomplicated hypertension (mean age 64±8 SD years, 53% women) over 12 months. Reading-to-reading BPV (from 24-hour ambulatory BP) and day-to-day BPV (from 7-day home BP) were assessed at baseline and 12 months, and visit-to-visit BPV (clinic BP) was assessed from 5 visits over 12 months. LVMI was measured by 3D echocardiography and aPWV with applanation tonometry. The strongest predictors of the changes in LVMI (ΔLVMI) were the changes in mean 24-hour systolic BPs (SBPs) (P < 0.02). Similarly, the strongest predictors of the changes in aPWV (ΔaPWV) were the changes in mean 24-hour ambulatory SBPs (P < 0.01) and the changes in mean clinic SBP (P 0.05 for all). Changes in mean BP levels, but not BPV, were most relevant to changes in TOD in patients with uncomplicated hypertension. Thus, from this point of view, BPV appears to have limited clinical utility in this patient population.
Publisher: Springer Science and Business Media LLC
Date: 12-03-2022
Publisher: Wiley
Date: 11-08-2020
DOI: 10.1111/JCH.13969
Publisher: Oxford University Press (OUP)
Date: 16-04-2016
DOI: 10.1093/AJH/HPW039
Abstract: Central blood pressure (CBP) independently predicts cardiovascular risk, but calibration methods may affect accuracy of central systolic blood pressure (CSBP). Standard central systolic blood pressure (Stan-CSBP) from peripheral waveforms is usually derived with calibration using brachial SBP and diastolic BP (DBP). However, calibration using oscillometric mean arterial pressure (MAP) and DBP (MAP-CSBP) is purported to provide more accurate representation of true invasive CSBP. This study sought to determine which derived CSBP could more accurately discriminate cardiac structural abnormalities. A total of 349 community-based patients with risk factors (71±5years, 161 males) had CSBP measured by brachial oscillometry (Mobil-O-Graph, IEM GmbH, Stolberg, Germany) using 2 calibration methods: MAP-CSBP and Stan-CSBP. Left ventricular hypertrophy (LVH) and left atrial dilatation (LAD) were measured based on standard guidelines. MAP-CSBP was higher than Stan-CSBP (149±20 vs. 128±15mm Hg, P < 0.0001). Although they were modestly correlated (rho = 0.74, P < 0.001), the Bland-Altman plot demonstrated a large bias (21mm Hg) and limits of agreement (24mm Hg). In receiver operating characteristic (ROC) curve analyses, MAP-CSBP significantly better discriminated LVH compared with Stan-CSBP (area under the curve (AUC) 0.66 vs. 0.59, P = 0.0063) and brachial SBP (0.62, P = 0.027). Continuous net reclassification improvement (NRI) (P < 0.001) and integrated discrimination improvement (IDI) (P < 0.001) corroborated superior discrimination of LVH by MAP-CSBP. Similarly, MAP-CSBP better distinguished LAD than Stan-CSBP (AUC 0.63 vs. 0.56, P = 0.005) and conventional brachial SBP (0.58, P = 0.006), whereas Stan-CSBP provided no better discrimination than conventional brachial BP (P = 0.09). CSBP is calibration dependent and when oscillometric MAP and DBP are used, the derived CSBP is a better discriminator for cardiac structural abnormalities.
Publisher: Wiley
Date: 27-06-2011
Publisher: Elsevier BV
Date: 05-2006
DOI: 10.1016/J.JACC.2006.02.042
Abstract: Our study attempted to validate a Doppler index of diastolic filling (E/E') during exercise with simultaneously measured left ventricular diastolic pressure (LVDP), investigate its association with exercise capacity, and understand which patients to select for testing. The ratio of early diastolic transmitral velocity to early diastolic tissue velocity approximates LVDP at rest, but there is limited validation of exercise E/E' with invasive hemodynamic measurement, and its clinical implications are unclear. The ratio of early diastolic transmitral velocity to early diastolic tissue velocity was measured at rest and during supine cycle ergometry in 37 patients undergoing left heart catheterization. In addition to correlation between invasive and estimated LVDP, the accuracy of different cutoffs for identification of elevated LVDP (>15 mm Hg) was determined at both rest and exercise. Doppler index of diastolic filling was also measured at rest and immediately after maximal treadmill exercise in 166 patients to investigate the association between exercise E/E' and exercise capacity ( 13 was highly specific (90%) for reduced exercise capacity, and even after classification of resting E/E', exercise E/E' permitted classification of patients with exercise capacity or =8 METs. The ratio of early diastolic transmitral velocity to early diastolic tissue velocity correlates with invasively measured LVDP during exercise. It can be used to reliably identify patients with elevated LVDP during exercise and reduced exercise capacity.
Publisher: Elsevier BV
Date: 2013
DOI: 10.1016/J.ATHEROSCLEROSIS.2012.10.047
Abstract: Exaggerated exercise blood pressure (BP) predicts mortality. Some studies suggest this could be explained by chronic hyperlipidemia, but whether acute-hyperlipidemia effects exercise BP has never been tested, and was the aim of this study. Intravenous infusion of saline (control) and Intralipid were administered over 60 min in 15 healthy men by double-blind, randomized, cross-over design. Brachial and central BP (including, pulse pressure, augmentation pressure and augmentation index), cardiac output and systemic vascular resistance were recorded at rest and during exercise. Compared with control, Intralipid caused significant increases in serum triglycerides, very low density lipoproteins and free fatty acids (p 0.05 for all). Acute-hyperlipidemia does not significantly change exercise hemodynamics in healthy males. Therefore, the association between raised lipids and increased exercise BP is likely due to the chronic effects of hyperlipidemia.
Publisher: Public Library of Science (PLoS)
Date: 30-12-2014
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 04-2020
Publisher: Springer Science and Business Media LLC
Date: 21-03-2022
DOI: 10.1038/S41371-022-00670-4
Abstract: A recent study found that only 23.8% of blood pressure (BP) devices available for purchase from Australian pharmacies were validated for accuracy. The extent to which pharmacists are aware of this, and other issues related to the accuracy of BP devices, is not known and gathering this information was the aim of this study. An online survey of Australian pharmacists was distributed via the Pharmaceutical Society of Australia between 1 October and 25 November 2020. Questions were focused on the views of pharmacists related to the accuracy of BP devices. Two hundred and ten pharmacists completed the survey. The accuracy of BP devices sold by pharmacists was considered 'quite' or 'extremely important' to most respondents (94%). However, most respondents (90%) were unaware that less than one-quarter of BP devices sold by Australian pharmacies were validated, and this was 'quite' or 'extremely surprising' to many (69%). Many respondents (64%) associated a particular brand of BP device with greater accuracy. There was low awareness on proper ways to identify accurate BP devices, such as checking reputable online databases (43%). BP devices were stocked in respondents' pharmacies based on perceived quality (50%), accuracy (40%), or as determined by the pharmacy chain (36%). In conclusion, providing accurate BP devices to consumers is important to pharmacists, but they were generally unaware that most devices available from pharmacies were not validated for accuracy. Pharmacist education, alongside advocacy for policies including regulations and strategic action, is required to ensure only validated BP devices are sold in Australia.
Publisher: Elsevier BV
Date: 10-2015
Publisher: SAGE Publications
Date: 14-06-2023
DOI: 10.1177/0310057X221140128
Abstract: Carbetocin and oxytocin are commonly recommended agents for active management of the third stage of labour. Evidence is inconclusive whether either one more effectively reduces the occurrence of important postpartum haemorrhage outcomes at caesarean section. We examined whether carbetocin is associated with a lower risk of severe postpartum haemorrhage (blood loss ≥ 1000 ml) in comparison with oxytocin for the third stage of labour in women undergoing caesarean section. This was a retrospective cohort study among women undergoing scheduled or intrapartum caesarean section between 1 January 2010 and 2 July 2015 who received carbetocin or oxytocin for the third stage of labour. The primary outcome was severe postpartum haemorrhage. Secondary outcomes included blood transfusion, interventions, third stage complications and estimated blood loss. Outcomes were examined overall and by timing of birth, scheduled versus intrapartum, using propensity score-matched analysis. Among 21,027 eligible participants, 10,564 women who received carbetocin and 3836 women who received oxytocin at caesarean section were included in the analysis. Carbetocin was associated with a lower risk of severe postpartum haemorrhage overall (2.1% versus 3.3% odds ratio, 0.62 95% confidence interval 0.48 to 0.79 P 0.001). This reduction was apparent irrespective of timing of birth. Secondary outcomes also favoured carbetocin over oxytocin. In this retrospective cohort study, the risk of severe postpartum haemorrhage associated with carbetocin was lower than that associated with oxytocin in women undergoing caesarean section. Randomised clinical trials are needed to further investigate these findings.
Publisher: Elsevier BV
Date: 2014
DOI: 10.1016/J.JOCA.2013.10.022
Abstract: There is evidence to suggest vascular involvement in the initiation and progression of osteoarthritis (OA). The relationship between large artery characteristics and pathogenesis of OA has not been investigated and was the aim of this study. Large artery characteristics (i.e., aortic stiffness, brachial and central blood pressure (BP) variables) and bone marrow lesions (BMLs measured by magnetic resonance imaging as a surrogate index of OA) were recorded in 208 participants (aged 63 ± 7 years mean ± SD) with symptomatic knee OA. Relationships between large artery characteristics and BML were assessed by multiple regression adjusting for age, sex and body mass index. There was a high prevalence of BML presence in the study population (70%), but no significant difference between participants with and without BML for all large artery and BP variables (P > 0.05 all). Furthermore, there were no significant relationships between BML size and aortic stiffness (r = -0.033, P = 0.71), central pulse pressure (r = 0.028, P = 0.74), augmentation index (r = 0.125, P = 0.14), brachial pulse pressure (r = 0.005, P = 0.95) or brachial systolic BP (r = -0.066, P = 0.44). When participants were stratified according to high or low aortic stiffness, there was no significant difference between groups regarding the proportion of those with a BML (64% vs. 70% respectively P = 0.69). Variables indicative of large artery characteristics are not significantly correlated with BML size or presence in people with symptomatic knee OA. Thus, large artery characteristics may not have a causative influence in the development of OA, but this needs to be confirmed in prospective studies.
Publisher: Springer Science and Business Media LLC
Date: 27-03-2012
DOI: 10.1038/IJO.2012.44
Publisher: Elsevier BV
Date: 02-2022
DOI: 10.1016/J.JSAMS.2021.09.008
Abstract: A hypertensive response to submaximal exercise is associated with cardiovascular disease but this relationship is influenced by functional capacity. Spironolactone improves functional capacity, which could mask treatment effects on exercise blood pressure. This study sought to examine this hypothesis. Retrospective analysis of a randomized clinical trial. 102 participants (54 ± 9 years 52% male) with a hypertensive response to maximal exercise (systolic BP ≥210 mm Hg men ≥190 mm Hg women) were randomized to 3-month spironolactone 25 mg daily (n = 53) or placebo (n = 49). Submaximal exercise blood pressure was measured during low-intensity cycling (50, 60 or 70% age-predicted maximal heart rate). Functional capacity was measured as maximal oxygen capacity obtained during a maximal treadmill exercise test, and (resting) aortic stiffness by carotid-to-femoral pulse wave velocity. Spironolactone improved submaximal exercise systolic blood pressure vs. placebo (-4 ± 16 vs. 2 ± 15 mm Hg, p = 0.045, Cohen's d = 0.42), and had a small (but non-statistically significant) improvement in functional capacity (0.64 ± 5.10 vs. -1.43 ± 5.04 ml/kg/min, p = 0.06, Cohen's d = 0.4). When treatment effects were expressed as the change in submaximal exercise systolic blood pressure relative to the change in functional capacity, a larger effect size was observed (-0.3 ± 1.1 vs. 0.3 ± 1.1 mm Hg/ml·kg·min Spironolactone reduces submaximal exercise blood pressure, but this treatment effect may be hidden by improved functional capacity and a non-fixed workload. This highlights the most clinically relevant exercise blood pressure is at a low intensity and fixed workload where the influence of fitness on exercise blood pressure is removed, and the effects of therapy can be appreciated.
Publisher: Springer Science and Business Media LLC
Date: 12-04-2011
DOI: 10.1038/IJO.2011.79
Abstract: Body size is associated with increased brachial systolic blood pressure (SBP) and aortic stiffness. The aims of this study were to determine the relationships between central SBP and body size (determined by body mass index (BMI), waist circumference and waist/hip ratio) in health and disease. We also sought to determine if aortic stiffness was correlated with body size, independent of BP. BMI, brachial BP and estimated central SBP (by SphygmoCor and radial P2) were recorded in controls (n=228), patients with diabetes (n=211), coronary artery disease (n=184) and end-stage kidney disease (n=68). Additional measures of waist circumference and arterial stiffness (aortic and brachial pulse wave velocity (PWV)) were recorded in a subgroup of 75 controls (aged 51 ± 12 years) who were carefully screened for factors affecting vascular function. BMI was associated with brachial (r=0.30 P<0.001) and central SBP (r=0.29 P<0.001) in the 228 controls, but not the patient populations (r 0.15 for all comparisons). In the control subgroup, waist circumference was also significantly correlated with brachial SBP (r=0.29 P=0.01), but not central SBP (r=0.22 P=0.07). Independent predictors of aortic PWV in the control subgroup were brachial SBP (β=0.43 P<0.001), age (β=0.37 P<0.001), waist circumference (β=0.39 P=0.02) and female sex (β=-0.24 P=0.03), but not BMI. In health, there are parallel increases in central and brachial SBP as BMI increases, but these relationships are not observed in the presence of chronic disease. Moreover, BP is a stronger correlate of arterial stiffness than body size.
Publisher: Pan American Health Organization
Date: 26-02-2021
Abstract: Cerca de ¼ dos adultos têm hipertensão arterial, que é o fator de risco isolado mais importante para morte (incluídas as mortes por cardiopatia e acidente vascular cerebral). Existem políticas eficazes que poderiam facilitar escolhas pessoais saudáveis para evitar a elevação da pressão arterial e, se plenamente implementadas, podem prevenir a ocorrência da hipertensão arterial. É fácil rastrear e tratar a hipertensão, MAS somente cerca de 50% dos adultos hipertensos estão cientes de sua condição, e apenas cerca de 1 em cada 7 é tratado adequadamente. A prevenção e controle da hipertensão é o principal mecanismo de prevenção e controle das doenças não transmissíveis e um modelo para outros riscos de doenças não transmissíveis. Tratamentos eficazes com mudanças de estilo de vida e medicamentos poderiam prevenir e controlar a hipertensão arterial na maioria das pessoas se aplicados sistematicamente à população as intervenções simples são viáveis em todos os ambientes e podem melhorar a atenção primária. É necessária a ação continuada e urgente a fim de obter mudanças efetivas nas políticas públicas e no sistema de saúde para prevenir e controlar a hipertensão arterial.
Publisher: Pan American Health Organization
Date: 26-02-2021
Abstract: Cerca de una cuarta parte de los adultos tienen hipertensión, el principal factor de riesgo de muerte (inclusive la causada por cardiopatía y accidente cerebrovascular). Existen políticas eficaces que podrían ayudar a las personas a elegir opciones saludables para prevenir el aumento de la presión arterial si se las aplicara plenamente, se podría evitar en gran medida el desarrollo de hipertensión. La hipertensión es fácil de detectar y tratar, PERO solo alrededor de 50% de los adultos que presentan dicha afección son conscientes de su situación y solamente 1 de cada 7 de ellos recibe el tratamiento adecuado. La prevención y el control de la hipertensión es el mecanismo principal para prevenir y controlar las enfermedades no transmisibles y un modelo para evitar otros riesgos de presentar dichas enfermedades. La adopción de un modo de vida saludable y el tratamiento farmacológico efectivo podrían prevenir y controlar la hipertensión en la mayoría de las personas si se implementaran de manera sistemática en la población en todos los entornos es posible aplicar intervenciones sencillas, que pueden usarse para mejorar la atención primaria. Es urgente adoptar medidas sostenidas para introducir cambios eficaces en las políticas públicas y los sistemas de salud pública con miras a prevenir y controlar la hipertensión.
Publisher: Springer Science and Business Media LLC
Date: 26-07-2012
DOI: 10.1038/HR.2012.111
Publisher: Elsevier BV
Date: 2016
Abstract: There is evidence that renal transplant recipients have accelerated atherosclerosis that is manifest by increased cardiovascular morbidity and mortality. The high incidence of atherosclerosis is, in part, related to increased arterial stiffness, vascular dysfunction, elevated oxidative stress, and inflammation associated with immunosuppressive therapy. The carotenoid astaxanthin has shown potent antioxidant and anti-inflammatory properties. The aim was to investigate the effects of oral astaxanthin on arterial stiffness, oxidative stress, and inflammation in renal transplant recipients. This trial used a randomized, placebo-controlled, double-blind design in which 61 patients received either 12 mg astaxanthin/d or an identical placebo orally for 1 y. Primary outcomes were 1) arterial stiffness measured by aortic pulse wave velocity (PWV), 2) oxidative stress assessed by total plasma F2-isoprostanes, and 3) inflammation assessed by plasma pentraxin-3. Secondary outcomes included vascular function, carotid artery intima-media thickness, augmentation index, central blood pressure, subendocardial viability ratio, and additional measures of oxidative stress and inflammation. Patients underwent assessments at baseline and at 6 and 12 mo. Fifty-eight participants completed the study. There were no significant between-group differences in the changes in any of the primary outcome measures (PWV changed by +9.5% and +6.0%, F2-isoprostanes changed by -3.0% and -9.7%, and pentraxin-3 changed by +50.6% and -11.0% in the placebo and astaxanthin groups, respectively). There were no significant between-group differences in secondary outcome measures. Larger-than-expected variability decreased the power of the study and increased the possibility of a type 2 statistical error. Astaxanthin (12 mg/d for 12 mo) had no effect on arterial stiffness, oxidative stress, or inflammation in renal transplant recipients. This trial was registered at the Australian New Zealand Clinical Trials Registry (www.anzctr.org.au/) as ACTRN12608000159358.
Publisher: Oxford University Press (OUP)
Date: 02-2020
DOI: 10.1093/AJH/HPAA013
Abstract: Central artery reservoir-excess pressure parameters are clinically important but impractical to record directly. However, diastolic waveform morphology is consistent across central and peripheral arteries. Therefore, peripheral artery reservoir-excess pressure parameters related to diastolic waveform morphology may be representative of central parameters and share clinically important associations with end-organ damage. This has never been determined and was the aim of this study. Intra-arterial blood pressure (BP) waveforms were measured sequentially at the aorta, brachial, and radial arteries among 220 in iduals (aged 61 ± 10 years, 68% male). Customized software was used to derive reservoir-excess pressure parameters at each arterial site (reservoir and excess pressure, systolic and diastolic rate constants) and clinical relevance was determined by association with estimated glomerular filtration rate (eGFR). Between the aorta and brachial artery, the mean difference in the diastolic rate constant and reservoir pressure integral was −0.162 S−1 (P = 0.08) and −0.772 mm Hg s (P = 0.23), respectively. The diastolic rate constant had the strongest and most consistent associations with eGFR across aortic and brachial sites (β = −0.20, P = 0.02 β = −0.20, P = 0.03, respectively adjusted for traditional cardiovascular risk factors). Aortic, but not brachial peak reservoir pressure was associated with eGFR in adjusted models (aortic β = −0.48, P = 0.02). The diastolic rate constant is the most consistent reservoir-excess pressure parameter, in both its absolute values and associations with kidney dysfunction, when derived from the aorta and brachial artery. Thus, the diastolic rate constant could be utilized in the clinical setting to improve BP risk stratification.
Publisher: Wiley
Date: 07-2020
DOI: 10.1111/JCH.13933
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 06-2019
DOI: 10.1161/HYPERTENSIONAHA.118.12186
Abstract: Large artery stiffness is an index of vascular aging associated with cardiovascular mortality. Whereas traditional risk factors for arterial stiffness are known, the contribution of socioeconomic factors is less reported. We sought to determine the relationship between arterial stiffness and socioeconomic deprivation (at the in idual and neighborhood levels) in healthy males and females. In 7803 adults, carotid stiffness was determined by high-precision carotid echo-tracking. In idual deprivation data included education, living alone, occupation, and Evaluation of the Deprivation and Inequalities of Health in Healthcare Centers score. Neighborhood deprivation was determined from commune level data (smallest administrative sub ision) available from French National Institute of Statistics and Economic Studies (2011) using principal component analysis. The separate and combined associations between in idual and neighborhood deprivation (main exposures) and carotid stiffness (outcome) were quantified using linear and multilevel model adjusted for traditional risk factors. Analyses were conducted separately in males and females. In idual deprivation (lower education and occupation in males and living alone and higher Evaluation of the Deprivation and Inequalities of Health in Healthcare Centers in both populations) was adversely related to carotid stiffness, independently of potential confounders ( P .05). Neighborhood deprivation was adversely related to carotid stiffness in males ( P .05), but not in females. Socioeconomic deprivation, both at in idual and, to a lesser extent, neighborhood level are associated with carotid stiffness in males. Only in idual deprivation is associated with carotid stiffness in females.
Publisher: Oxford University Press (OUP)
Date: 08-2011
DOI: 10.1038/AJH.2011.75
Abstract: A hypertensive response to exercise (HRE defined as normal clinic blood pressure (BP) and exercise systolic BP (SBP) ≥210 mm Hg in men or ≥190 mm Hg in women, or diastolic BP (DBP) ≥105 mm Hg) independently predicts mortality. The mechanisms remain unclear but may be related to masked hypertension. This study aimed to assess the prevalence of masked hypertension and its association with cardiovascular risk factors, including left ventricular (LV) mass, in patients with a HRE. Comprehensive clinical and echocardiographic evaluation (including central BP, aortic pulse wave velocity by tonometry) and 24-h ambulatory BP monitoring (ABPM) were performed in 72 untreated patients with HRE (aged 54 ± 9 years 60% male free from coronary artery disease confirmed by exercise stress echocardiography). Masked hypertension was defined according to guidelines as daytime ABPM ≥135/85 mm Hg and clinic BP 0.05 for both). The strongest independent determinant of LV mass index was the presence of masked hypertension (unstandardized β = 5.6 P = 0.007), which was also independently related to LV RWT (unstandardized β = 0.04 P = 0.03). Masked hypertension is highly prevalent in HRE patients with a normal resting office BP and is associated with increased LV mass index and RWT. Clinicians should consider measuring ABPM or home BP in HRE patients.
Publisher: Springer Science and Business Media LLC
Date: 18-11-2013
DOI: 10.1007/S00421-012-2543-1
Abstract: Aortic pulse wave velocity (PWV) and augmentation index (AIx) are independent predictors of cardiovascular risk and mortality, but little is known about the effect of air temperature changes on these variables. Our study investigated the effect of exposure to whole-body mild-cold on measures of arterial stiffness (aortic and brachial PWV), and on central haemodynamics [including augmented pressure (AP), AIx], and aortic reservoir components [including reservoir and excess pressures (P ex)]. Sixteen healthy volunteers (10 men, age 43 ± 19 years mean ± SD) were randomised to be studied under conditions of 12 °C (mild-cold) and 21 °C (control) on separate days. Supine resting measures were taken at baseline (ambient temperature) and after 10, 30, and 60 min exposure to each experimental condition in a climate chamber. There was no significant change in brachial blood pressure between mild-cold and control conditions. However, compared to control, AP [+2 mmHg, 95 % confidence interval (CI) 0.36-4.36 p = 0.01] and AIx (+6 %, 95 % CI 1.24-10.1 p = 0.02) increased, and time to maximum P ex (a component of reservoir function related to timing of peak aortic in-flow) decreased (-7 ms, 95 % CI -15.4 to 2.03 p = 0.01) compared to control. Yet there was no significant change in aortic PWV (+0.04 m/s, 95 % CI -0.47 to 0.55 p = 0.87) or brachial PWV (+0.36 m/s -0.41 to 1.12 p = 0.35) between conditions. We conclude that mild-cold exposure increases central haemodynamic stress and alters timing of peak aortic in-flow without differentially affecting arterial stiffness.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 06-2019
Publisher: Oxford University Press (OUP)
Date: 13-06-2018
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 12-2018
Publisher: Informa UK Limited
Date: 11-2002
DOI: 10.1080/00039890209602085
Abstract: Low-density lipoprotein oxidation is implicated in the development of atherosclerosis. Plasma susceptibility to oxidation may be used as a marker of low-density lipoprotein oxidation and thus predict atherosclerotic risk. In this study the authors investigated the relationship between plasma susceptibility to oxidation and exposure to automotive pollution in a group of automobile mechanics (n = 16) exposed to high levels of automotive pollution, vs. matched controls (n = 13). The authors induced plasma oxidation by a free radical initiator and they determined susceptibility to oxidation by (1) change in absorbance at 234 nm, (2) lag time to conjugated diene formation, and (3) linear slope of the oxidation curve. Mechanics had significantly higher values (mean +/- standard error) for change in absorbance (1.60 +/- 0.05 vs. 1.36 +/- 0.05 p < .002), and slope (1.6 x 10(-3) +/- 0.1 x 10(-3) vs. 1.3 x 10(-3) +/- 0.1 x 10(-3) p < .001), compared with controls. These results indicate that regular exposure to automotive pollutants increases plasma susceptibility to oxidation and may, in the long-term, increase the risk of developing atherosclerosis.
Publisher: Springer Science and Business Media LLC
Date: 31-10-2018
DOI: 10.1038/S41371-018-0122-6
Abstract: Hypertension is the most significant modifiable risk factor for cardiovascular disease and contributes to the highest global burden of disease. Blood pressure (BP) measurement is among the most important of all medical tests, and it is critical for BP monitoring devices to be accurate. Comprehensive new evidence from meta-analyses clearly shows that many BP monitoring devices (including oscillometric machines and "gold standard" mercury auscultation) do not accurately represent the BP within the arteries at the upper arm (brachial) or central aorta. Particular variability in the accuracy of BP devices compared with intra-arterial BP has been demonstrated in the cuff BP range from prehypertension to grade I hypertension (systolic BP 120-159 to diastolic BP 80-99 mmHg). This is within the BP range that is most common among people worldwide and, thus almost certainly, feeding confusion around optimal hypertension guideline thresholds. At the in idual level, inaccurate BP devices have major potential consequences for best practice patient management, where underestimation of true BP is a missed opportunity to lower cardiovascular risk (with therapeutics or lifestyle) and overestimation of true BP could lead to overmedication. Each problem leads to increased cost from preventable cardiovascular events and unnecessary medications. Altogether, there is a critical need to improve the accuracy standards of BP monitoring devices. In the meantime, out-of-office BP (24 h of ambulatory BP and/or home BP monitoring) or automated, unobserved in-office BP monitoring that takes the average of multiple readings using validated devices are the best available options to determine BP control.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 06-2020
DOI: 10.1161/HYPERTENSIONAHA.120.14719
Abstract: Self-home blood pressure (BP) monitoring is recommended to guide clinical decisions on hypertension and is used worldwide for cardiovascular risk management. People usually make their own decisions when purchasing BP devices, which can be made online. If patients purchase nonvalidated devices (those not proven accurate according to internationally accepted standards), hypertension management may be based on inaccurate readings resulting in under- or over-diagnosis or treatment. This study aimed to evaluate the number, type, percentage validated, and cost of home BP devices available online. A search of online businesses selling devices for home BP monitoring was conducted. Multinational companies make worldwide deliveries, so searches were restricted to BP devices available for one nation (Australia) as an ex le of device availability through the global online marketplace. Validation status of BP devices was determined according to established protocols. Fifty nine online businesses, selling 972 unique BP devices were identified. These included 278 upper-arm cuff devices (18.3% validated), 162 wrist-cuff devices (8.0% validated), and 532 wrist-band wearables (0% validated). Most BP devices (92.4%) were stocked by international e-commerce businesses (eg, eBay, Amazon), but only 5.5% were validated. Validated cuff BP devices were more expensive than nonvalidated devices: median (interquartile range) of 101.1 (75.0–151.5) versus 67.4 (30.4–112.8) Australian Dollars. Nonvalidated BP devices dominate the online marketplace and are sold at lower cost than validated ones, which is a major barrier to accurate home BP monitoring and cardiovascular risk management. Before purchasing a BP device, people should check it has been validated at www.stridebp.org .
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 06-10-2020
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 09-2012
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 07-2016
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 13-07-2023
DOI: 10.1097/HJH.0000000000003510
Abstract: Hypertension management is directed by cuff blood pressure (BP), but this may be inaccurate, potentially influencing cardiovascular disease (CVD) events and health costs. This study aimed to determine the impact on CVD events and related costs of the differences between cuff and invasive SBP. Microsimulations based on Markov modelling over one year were used to determine the differences in the number of CVD events (myocardial infarction or coronary death, stroke, atrial fibrillation or heart failure) predicted by Framingham risk and total CVD health costs based on cuff SBP compared with invasive (aortic) SBP. Modelling was based on international consortium data from 1678 participants undergoing cardiac catheterization and 30 separate studies. Cuff underestimation and overestimation were defined as cuff SBP less than invasive SBP and cuff SBP greater than invasive SBP, respectively. The proportion of people with cuff SBP underestimation versus overestimation progressively increased as SBP increased. This reached a maximum ratio of 16 : 1 in people with hypertension grades II and III. Both the number of CVD events missed (predominantly stroke, coronary death and myocardial infarction) and associated health costs increased stepwise across levels of SBP control, as cuff SBP underestimation increased. The maximum number of CVD events potentially missed (11.8/1000 patients) and highest costs ($241 300 USD/1000 patients) were seen in people with hypertension grades II and III and with at least 15 mmHg of cuff SBP underestimation. Cuff SBP underestimation can result in potentially preventable CVD events being missed and major increases in health costs. These issues could be remedied with improved cuff SBP accuracy.
Publisher: Wiley
Date: 16-06-2014
DOI: 10.1111/JGS.12925
Abstract: To determine whether there is a relationship between daily defined dose (DDD) of antihypertensive drugs and the risk of falls. Prospective population-based cohort study. Tasmanian Study of Cognition and Gait, Australia. Participants aged 60 to 86 randomly selected from the electoral roll. Antihypertensive dose was quantified by estimating DDD, allowing standardized comparison of dosage between drug classes. Falls were identified prospectively over 12 months. The relative risk (RR) of falls associated with DDD was estimated using log binomial regression adjusting for age, sex, body mass index, education, cardiovascular history, and other risk factors for falls. Participants (N=409) had a mean age of 72.0±6.9, and 56% were male. Mean baseline blood pressure was 142/80 mmHg, and 54% were taking antihypertensive medications. One hundred sixty-one participants (39%) fell over the 12 months. Those who fell were on a higher DDD of antihypertensives (1.51±2.16 than those who did not (1.03±1.42) (P=.007). Higher DDD was independently associated with greater fall risk (RR=1.07, 95% confidence interval (CI)=1.02-1.11 P=.004), with a 48% greater risk in those with a DDD of more than 3 (RR=1.48, 95% CI=1.06-2.08 P=.02), particularly in those with a history of stroke (P for interaction .01). This effect remained even after excluding those not taking antihypertensives or stratifying according to presence of hypertension and medication use. Higher dose of antihypertensive medication is independently associated with falls in older people, particularly in those with a history of previous stroke, and with more than three standard units conferring the highest risk.
Publisher: Elsevier BV
Date: 11-2023
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 2012
Publisher: Springer Science and Business Media LLC
Date: 12-01-2012
DOI: 10.1038/HR.2011.219
Abstract: A strong association between blood pressure (BP) and body mass index (BMI) has been observed in developed and developing countries. Whether there are differences in these associations between Caucasians and Asians remains unknown. Our objective was to compare the associations of BP with fatness measures in the Caucasian and Asian s les. The study used data from two population-based cross-sectional studies conducted using similar methodology: a survey in Australia in 1998-1999 (n = 832 adults aged 25-64 years 47% male) and a survey in Vietnam in 2005 (n = 1978 adults aged 25-64 years 46% male). Participants completed questionnaires and attended clinics for physical measurements including BP and anthropometry. Linear regression was used for analysis. Independent of age, there were strong associations between BP indices and BMI in each s le, but the patterns of associations were different. Among Caucasians, pulse pressure (PP) increased with increasing BMI because the slope of systolic pressure with BMI exceeded the slope of diastolic pressure with BMI (P<0.001 for both sexes). In contrast, among Asians, PP decreased with increasing BMI. Associations between BMI and BP are different between Caucasian and Asian populations. Among Asians, the stronger association of increasing BMI and diastolic BP, but not PP, suggests a different pathophysiology related to hypertension.
Publisher: Wiley
Date: 02-2020
DOI: 10.1111/JCH.13821
Publisher: Wroclaw Medical University
Date: 05-10-2021
DOI: 10.17219/ACEM/141863
Publisher: Wiley
Date: 17-09-2007
Publisher: American Physiological Society
Date: 05-2015
DOI: 10.1152/AJPHEART.00739.2014
Abstract: Exercise-induced albuminuria is common in patients with type 2 diabetes mellitus (T2DM) in response to maximal exercise, but the response to light-moderate exercise is unclear. Patients with T2DM have abnormal central hemodynamics and greater propensity for exercise hypertension. This study sought to determine the relationship between light-moderate exercise central hemodynamics (including aortic reservoir and excess pressure) and exercise-induced albuminuria. Thirty-nine T2DM (62 ± 9 yr 49% male) and 39 nondiabetic controls (53 ± 9 yr 51% male) were examined at rest and during 20 min of light-moderate cycle exercise (30 W 50 revolutions/min). Albuminuria was assessed by the albumin-creatinine ratio (ACR) at rest and 30 min postexercise. Hemodynamics recorded included brachial and central blood pressure (BP), aortic stiffness, augmented pressure (AP), aortic reservoir pressure, and excess pressure integral (P excess ). There was no difference in ACR between groups before exercise ( P 0.05). Exercise induced a significant rise in ACR in T2DM but not controls (1.73 ± 1.43 vs. 0.53 ± 1.0 mg/mol, P = 0.002). All central hemodynamic variables were significantly higher during exercise in T2DM (i.e., P excess , systolic BP and AP P 0.01 all). In T2DM (but not controls), exercise P excess was associated with postexercise ACR ( r = 0.51, P = 0.002), and this relationship was independent of age, sex, body mass index, heart rate, aortic stiffness, antihypertensive medication, and ambulatory daytime systolic BP (β = 0.003, P = 0.003). Light-moderate exercise induced a significant rise in ACR in T2DM, and this was independently associated with P excess , a potential marker of vascular dysfunction. These novel findings suggest that P excess could be important for appropriate renal function in T2DM.
Publisher: Oxford University Press (OUP)
Date: 04-12-2013
DOI: 10.1093/AJH/HPT222
Abstract: Mechanisms underlying the inverse relationship between height and cardiovascular mortality are unknown but could relate to central hemodynamics. We sought to determine the relation of height to central and peripheral hemodynamics, as well as clinical characteristics. The study population was comprised of 1,152 randomly selected community-dwelling adults (aged 67.7 ± 12.3 years 48% men). Brachial blood pressure (BP) was recorded by sphygmomanometry central BP and aortic pulse wave velocity were estimated by applanation tonometry. Stepwise multiple regression analysis was used to determine associations between height and central and peripheral hemodynamics. Height was not significantly associated with aortic pulse wave velocity in men or women. The relationship with height and brachial systolic BP was borderline in women (β = -0.115 P = 0.051) but not significant in men (β = -0.096 P = 0.09). Conversely, central systolic BP, estimated by transfer function (β = -0.139 for men [βM] β = -0.172 for women [βW]) or radial second systolic peak (β M = -0.239 β W = -0.281), augmentation index at 75 bpm (β M = -0.189 β W = -0.224), and aortic pulse wave timing (β M = 0.224 β W = 0.262) were independently associated with height in both sexes (P < 0.003 for all). Both men and women of greater than median height were less likely to have coronary artery disease (P < 0.05), to have systemic hypertension (P < 0.01), or to be taking vasoactive medication (P < 0.001) compared with participants of less than median height. Even after correcting for conventional cardiovascular risk factors, taller in iduals have more favorable central hemodynamics and reduced evidence of coronary artery disease compared with shorter in iduals. These findings may help explain the decreased cardiovascular risk associated with being taller and also have important clinical consequences regarding therapy.
Publisher: Springer Science and Business Media LLC
Date: 19-10-2023
Publisher: Wiley
Date: 13-04-2021
DOI: 10.1111/JEP.13569
Abstract: Absolute cardiovascular disease (aCVD) risk assessment is recommended in CVD prevention guidelines. Yet, General Practitioners (GPs) often focus on single risk factors, including blood pressure (BP). Pathology services may be suitable to undertake high‐quality automated unobserved BP (AOBP) measurement and aCVD risk assessment. This study explored GP attitudes towards AOBP measurement via pathology services and the role of BP in aCVD risk management. A brief survey was completed, after which a focus group (n = 8 GPs) and interviews (n = 10 GPs) explored attitudes to AOBP and aCVD risk via pathology services with an ex le pathology report discussed. Verbatim transcripts were thematically coded. GPs predominantly used doctor‐measured BP despite low levels of confidence. High BP measured by AOBP reported with aCVD risk via pathology services, would prompt a follow‐up response. However, GPs focused on BP management. GPs were concerned about AOBP equivalency to routine BP measurements. After protocol explanation, GPs reported AOBP could value‐add to care delivery. GPs lacked familiarity of AOBP and maintained a focus on BP management in the context of absolute CVD risk. Targeted education on AOBP and BP management as part of absolute CVD risk is needed to support guideline‐directed care in practice.
Publisher: Springer Science and Business Media LLC
Date: 2020
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 06-2016
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 21-06-2022
Abstract: Blood pressure associates with arterial stiffness, but the contribution of blood pressure at different life stages is unclear. We examined the relative contribution of childhood, young‐ and mid‐adulthood blood pressure to mid‐adulthood large artery stiffness. The s le comprised 1869 participants from the Cardiovascular Risk in Young Finns Study who had blood pressure measured in childhood (6–18 years), young‐adulthood (21–30 years), and mid‐adulthood (33–45 years). Markers of large artery stiffness were pulse wave velocity and carotid distensibility recorded in mid‐adulthood. Bayesian relevant life course exposure models were used. For each 10‐mm Hg higher cumulative systolic blood pressure across the life stages, pulse wave velocity was 0.56 m/s higher (95% credible interval: 0.49 to 0.63) and carotid distensibility was 0.13%/10 mm Hg lower (95% credible interval: −0.16 to −0.10). Of these total contributions, the highest contribution was attributed to mid‐adulthood systolic blood pressure (relative weights: pulse wave velocity, childhood: 2.6%, young‐adulthood: 5.4%, mid‐adulthood: 92.0% carotid distensibility, childhood: 5.6% young‐adulthood: 10.1% mid‐adulthood: 84.3%), with the greatest in idual contribution coming from systolic blood pressure at the time point when pulse wave velocity and carotid distensibility were measured. The results were consistent for diastolic blood pressure, mean arterial pressure, and pulse pressure. Although mid‐adulthood blood pressure contributed most to mid‐adulthood large artery stiffness, we observed small contributions from childhood and young‐adulthood blood pressure. These findings suggest that the burden posed by arterial stiffness might be reduced by maintaining normal blood pressure levels at each life stage, with mid‐adulthood a critical period for controlling blood pressure.
Publisher: Springer Science and Business Media LLC
Date: 09-03-2021
Publisher: Elsevier BV
Date: 07-2015
DOI: 10.1016/J.JSAMS.2014.07.005
Abstract: Reduced functional capacity is associated with poor prognosis. In patients with chronic kidney disease the factors that contribute to low cardiorespiratory fitness are unclear. The objective of this study was to evaluate the cardiorespiratory and cardiovascular response to exercise in chronic kidney disease patients, and secondly investigate the relationships between cardiorespiratory fitness and cardiovascular burden. Cross-sectional analysis. Baseline demographic, anthropometric and biochemical data were examined in 136 patients with moderate chronic kidney disease (age 59.7±9.6yrs, eGFR 40±9ml/min/1.73m(2), 55% male, 39% with a history of cardiovascular disease, 38% diabetic and 17% current smokers). Cardiorespiratory fitness was measured as peak VO2, left ventricular morphology and function using echocardiography, central arterial stiffness by aortic pulse wave velocity and left ventricular afterload using augmentation index. Physical activity levels were assessed using the Active Australia questionnaire. Peak VO2 (22.9±6.5ml/kg/min) and peak heart rate (148±22bpm) were 17% and 12% lower than the age-predicted values, respectively. The low fit group were significantly older, and were more likely to have type II diabetes, cardiovascular disease, a higher BMI and be less active than the high fit group (P<0.05). The independent predictors of peak VO2 were age, type II diabetes, hemoglobin level, physical activity, aortic pulse wave velocity, augmentation index, and global longitudinal strain. In patients with chronic kidney disease, the peak VO2 and heart rate response is markedly impaired. Reduced cardiorespiratory fitness is independently associated with increased aortic stiffness, increased left ventricle afterload, poor left ventricle function and higher burden of cardiovascular risk.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 2022
DOI: 10.1161/HYPERTENSIONAHA.121.17765
Abstract: Central (aortic) systolic blood pressure (cSBP) is the pressure seen by the heart, the brain, and the kidneys. If properly measured, cSBP is closer associated with hypertension-mediated organ damage and prognosis, as compared with brachial SBP (bSBP). We investigated 24-hour profiles of bSBP and cSBP, measured simultaneously using Mobilograph devices, in 2423 untreated adults (1275 women age, 18–94 years), free from overt cardiovascular disease, aiming to develop reference values and to analyze daytime-nighttime variability. Central SBP was assessed, using brachial waveforms, calibrated with mean arterial pressure (MAP)/diastolic BP (cSBP MAP/DBPcal ), or bSBP/diastolic blood pressure (cSBP SBP/DBPcal ), and a validated transfer function, resulting in 144 509 valid brachial and 130 804 valid central measurements. Averaged 24-hour, daytime, and nighttime brachial BP across all in iduals was 124/79, 126/81, and 116/72 mm Hg, respectively. Averaged 24-hour, daytime, and nighttime values for cSBP MAP/DBPcal were 128, 128, and 125 mm Hg and 115, 117, and 107 mm Hg for cSBP SBP/DBPcal , respectively. We pragmatically propose as upper normal limit for 24-hour cSBP MAP/DBPcal 135 mm Hg and for 24-hour cSBP SBP/DBPcal 120 mm Hg. bSBP dipping (nighttime-daytime/daytime SBP) was −10.6 % in young participants and decreased with increasing age. Central SBP SBP/DBPcal dipping was less pronounced (−8.7% in young participants). In contrast, cSBP MAP/DBPcal dipping was completely absent in the youngest age group and less pronounced in all other participants. These data may serve for comparison in various diseases and have potential implications for refining hypertension diagnosis and management. The different dipping behavior of bSBP versus cSBP requires further investigation.
Publisher: Oxford University Press (OUP)
Date: 10-2008
DOI: 10.1038/AJH.2008.253
Abstract: Central blood pressure (BP) and markers of wave reflection (augmentation index AIx) measured by radial tonometry have prognostic value independent from brachial BP. The measurement of the central waveform is increasingly used during altered hemodynamics, including exercise, but reliability of the test has not been reported under changed loading conditions. This study aimed to test the technique's reproducibility during major hemodynamic perturbations induced by exercise. Radial waveforms were recorded (SphygmoCor) in 28 healthy subjects (aged 53 +/- 11 years) at rest, during submaximal exercise (cycling at 50, 60, and 70% of maximal age-predicted heart rate (HR)) and immediately after maximal treadmill exercise on two occasions separated by 9 +/- 5 days. Data were compared between testing days. Waveforms were calibrated with brachial BP measured using a mercury sphygmomanometer. Pulse pressure lification (PPAmp) was defined as the ratio of brachial to central pulse pressure. There was very good reproducibility between visits at all exercise intensities for all waveform measures, including AIx, central pulse pressure, and PPAmp (intraclass correlations at 50% exercise were 0.93, 0.89, and 0.89, respectively P 0.05 for all). Radial tonometry is a reproducible technique for measurement of central waveform indices during perturbations induced by exercise. It should, therefore, be suitable for use in intervention studies in which hemodynamics are altered.
Publisher: American Astronomical Society
Date: 23-05-2023
Abstract: The Vera C. Rubin Observatory is expected to start the Legacy Survey of Space and Time (LSST) in early to mid-2025. This multiband wide-field synoptic survey will transform our view of the solar system, with the discovery and monitoring of over five million small bodies. The final survey strategy chosen for LSST has direct implications on the discoverability and characterization of solar system minor planets and passing interstellar objects. Creating an inventory of the solar system is one of the four main LSST science drivers. The LSST observing cadence is a complex optimization problem that must balance the priorities and needs of all the key LSST science areas. To design the best LSST survey strategy, a series of operation simulations using the Rubin Observatory scheduler have been generated to explore the various options for tuning observing parameters and prioritizations. We explore the impact of the various simulated LSST observing strategies on studying the solar system’s small body reservoirs. We examine what are the best observing scenarios and review what are the important considerations for maximizing LSST solar system science. In general, most of the LSST cadence simulations produce ±5% or less variations in our chosen key metrics, but a subset of the simulations significantly hinder science returns with much larger losses in the discovery and light-curve metrics.
Publisher: Springer Science and Business Media LLC
Date: 12-03-2009
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 26-07-2021
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 10-2016
Publisher: Wiley
Date: 06-2020
DOI: 10.1111/JCH.13916
Publisher: Springer Science and Business Media LLC
Date: 09-11-2007
Publisher: Wiley
Date: 06-2020
DOI: 10.1111/JCH.13915
Publisher: Oxford University Press (OUP)
Date: 05-09-2014
DOI: 10.1093/AJH/HPU163
Abstract: Central blood pressure (BP) can be estimated noninvasively by analyzing brachial artery waveforms. In this study, our aim was to assess the validity of a brachial cuff-based (suprasystolic) technique for estimating central BP (CBPestimated) by comparison with invasive aortic BP (CBPinvasive). Eighty-four simultaneous CBPestimated (Pulsecor R7.0) and CBPinvasive measures were recorded in 47 patients (aged 63±10 years, 62% male) undergoing coronary angiography. Measures were captured at baseline and acutely following intravenous glyceryl trinitrate (GTN 100-200 μg). Mean CBPinvasive systolic BP (SBP) and diastolic BP (DBP) were compared with CBPestimated SBP and DBP calibrated with brachial SBP and DBP recorded from the Pulsecor device. To test validity of the central BP algorithm, measures of CBPestimated SBP were also compared with CBPinvasive SBP following recalibration with invasive mean arterial pressure (MAP) and DBP. At baseline, mean difference ± standard deviation between CBPestimated SBP and CBPinvasive SBP was -7±9mm Hg (intraclass correlation coefficient (ICC) = 0.86 P < 0.001) with similar underestimation post-GTN (-6±9mm Hg ICC = 0.90 P < 0.001). Recalibration of CBPestimated SBP with invasive MAP and DBP resulted in closer mean difference to CBPinvasive SBP (-2±7mm Hg ICC = 0.95 P < 0.001) at baseline but not post-GTN (-6±7mm Hg ICC = 0.95 P < 0.001). The Pulsecor algorithm to derive central BP has acceptable validity when calibrated with invasive pressures. However, accuracy is compromised when noninvasive brachial cuff BP calibration is used.
Publisher: Elsevier BV
Date: 05-2013
DOI: 10.1016/J.ATHEROSCLEROSIS.2013.02.022
Abstract: Vascular damage is suggested to have origins in childhood adiposity, but it is not clear whether this is a direct consequence of being obese in childhood. We aimed to estimate the associations of childhood body size or adiposity with adult vascular health, and to investigate whether these associations were independent of adult body size or adiposity. Subjects were 2328 participants aged 7-15 years at baseline in 1985 with follow-up during 2004-2006 when aged 26-36 years. Anthropometric measures were taken at both baseline and follow-up. Carotid intima-media thickness (IMT) and three measures of large artery stiffness (LAS) were measured by ultrasound at follow-up. Childhood body size or adiposity was positively associated with both adult IMT and LAS. Participants who were obese in adulthood had the greatest LAS, particularly those who were normal weight in childhood. Adjustment for adult body size or adiposity eliminated effects of childhood body size or adiposity on LAS. For IMT, adjustment for adult body size or adiposity reduced estimated effects of child height by 44% (male) and 27% (female), of child weight by 46% (male) and 70% (female) and, after adjusting for sex, of child body mass index and body surface area by 60% and 53% respectively. Whereas IMT appeared to be influenced by body size or adiposity during childhood and early adulthood, LAS depended primarily on current adiposity and magnitude of adiposity gain between childhood and adulthood.
Publisher: Oxford University Press (OUP)
Date: 26-03-2019
Abstract: Functional and structural abnormalities of the left atrium have been demonstrated to be clinically and prognostically significant in a range of cardiovascular disorders, increasing the risk of atrial fibrillation. Among the potential contributors to these aberrations, central arterial factors remain insufficiently defined. Accordingly, we sought to investigate the determinants of left atrium abnormalities in hypertension, with special focus on central haemodynamics. In this retrospective, cross-sectional study, 263 patients (age 63.8 ± 8.0 years) with uncomplicated hypertension underwent echocardiography including left atrium strain (LAS) and volume analysis, and central haemodynamics assessment using radial tonometry. Patients were grouped depending on LAS and left atrium volume index (LAVI), using externally validated cutpoints (34.1% for LAS and 34 ml/m 2 for LAVI). The subset with lower LAS ( n = 124) demonstrated higher central (cPP) and brachial pulse pressure (bPP), ventricular- arterial coupling, left ventricular mass index (LVMI) and LAVI, and lower global left ventricular longitudinal strain and early diastolic tissue velocity (e′). Patients with higher LAVI ( n = 119) presented higher systolic blood pressure, cPP, bPP, central augmentation pressure, LVMI and E/e′ ratio and lower LAS. In multivariable analysis, cPP was independently associated with both LAS ( β = –0.22 p = 0.002) and LAVI ( β = 0.21 p = 0.003). No independent associations with left atrium parameters were shown for bPP. Higher cPP is detrimentally associated with left atrium structural and functional characteristics, thus providing a possible pathophysiological link with the development of substrate for atrial fibrillation. Prophylaxis of atrial fibrillation might be another argument for consideration in the treatment strategy in hypertension targeted measures addressing central blood pressure.
Publisher: Springer Science and Business Media LLC
Date: 20-12-2013
DOI: 10.1038/JHH.2012.60
Abstract: An abnormal increase or decrease in blood pressure (BP) in response to postural stress is associated with increased risk of developing hypertension and stroke. However, the haemodynamic responses contributing to changes in central BP with postural stress are not well characterised. We aimed to determine this in controls compared to patients with type 2 diabetes mellitus (T2DM), whom we hypothesised would have an abnormal postural response. 41 participants (20 control, 21 T2DM) underwent measurement of brachial and central BP (by radial tonometry), with simultaneous bioimpedance cardiography (to determine stroke volume (SV) and cardiac output (CO)) and heart rate variability in seated and standing postures. Systemic vascular resistance (SVR mean arterial pressure/CO), and arterial elastance (EA end systolic pressure/SV) were calculated. Postural changes were defined as seated minus standing values. Central pulse pressure (PP) was higher in patients with T2DM and did not change from seated-to-standing positions, whereas there was a significant decrease upon standing in controls (P<0.05). The change in central systolic BP (SBP) correlated with change in SVR and EA in controls (r=0.67 and 0.68, P 0.05, respectively). SV was the only significant correlate of change in central SBP in T2DM patients (r=0.62, P 0.05). We conclude that central haemodynamic responses to postural stress are altered in patients with T2DM and result in persistent elevation of central PP while standing. This may contribute to increased cardiovascular risk associated with T2DM.
Publisher: Oxford University Press (OUP)
Date: 10-2021
Abstract: Guidelines for cardiovascular disease (CVD) prevention recommend assessment of absolute CVD risk to guide clinical management. Despite this, use among general practitioners (GPs) remains limited. Pathology services may provide an appropriate setting to assess and report absolute CVD risk in patients attending for cholesterol measurement. This study aimed to explore GPs perceptions of such a service. A focus group and semi-structured interviews were conducted with GPs (n = 18) in Tasmania, Australia, to identify perceptions of assessment and reporting of absolute CVD risk via pathology services. An ex le pathology report including absolute CVD risk was provided and discussed. Audio-recordings were transcribed and thematically coded by two researchers. Almost all GPs identified that absolute CVD risk assessed and reported via pathology services could address deficits in practice. First, by reducing the number of appointments required to collect risk factors. Second, by providing a systematic (rather than opportunistic) approach for assessment of absolute CVD risk. Third, by reducing misclassification of patient CVD risk caused by overreliance on clinical intuition. All GPs reported they would order absolute CVD risk when issuing a cholesterol referral if such a service was offered. GPs recommended improving the service by providing information on methods used to measure risk factors on the pathology report. Absolute CVD risk assessed and reported via pathology services may address challenges of screening CVD risk experienced by GPs in practice and encourage dedicated follow-up care for CVD prevention.
Publisher: Elsevier BV
Date: 2019
Publisher: Springer Science and Business Media LLC
Date: 30-05-2013
DOI: 10.1038/JHH.2013.38
Abstract: Office blood pressure (BP) is recommended to be measured after 5 min of seated rest, but it may decrease for 10 min of seated rest. This study aimed to determine the change (and its clinical relevance) in brachial and central BP from 5 to 10 min of seated rest. Office brachial and central BP (measured after 5 and 10 min), left ventricular (LV) mass index, 7-day home and ambulatory BP were measured in 250 participants with treated hypertension. Office brachial and central BP were significantly lower at 10-min compared with 5-min BP (P<0.001). Seven-day home systolic BP (SBP) was significantly lower than office SBP measured at 5 min (P<0.001), but was similar to office SBP at 10 min (P=0.511). From 5 to 10 min, the percentage of participants with controlled BP increased and the percentage of participants with high central pulse pressure (PP) decreased (P<0.001). Moreover, brachial and central PP were significantly correlated with LV mass index measured at 10 min (r=0.171, P=0.006 and r=0.139, P=0.027, respectively), but not at 5 min (r=0.115, P=0.068 and r=0.084, P=0.185, respectively). BP recorded after 10 min is more representative of true BP control. These findings have relevance to appropriate diagnosis of hypertension and design of clinical trials.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 2020
Publisher: Springer Science and Business Media LLC
Date: 04-12-2017
DOI: 10.1007/S00431-017-3049-Y
Abstract: Blood pressure (BP) is variable in children and this could affect BP assessment, but the magnitude of within-visit BP variability (BPV) over consecutive measurements has never been investigated. This study aimed to determine the direction and magnitude of, and factors affecting, within-visit BPV in children and adolescents. BP was recorded among 3047 children (aged 12 years [95%CI 12, 13], males 52%) from the 2011-2013 Australian Health Survey. BPV was defined as the absolute difference (∆SBP BP is highly variable in children and adolescents, with the magnitude of variability being associated with both age and BP level. SBP increases on repeat measurement in a substantial proportion of the population. The optimal protocol of BP assessment to address this increased BPV needs to be determined. What is Known: • Diagnosis of elevated blood pressure (BP) is based on strict probabilistic criteria, the difference between the 90th (pre-hypertension) and 95th (hypertension) percentiles only being 3-4 mmHg. • BP variability could affect BP classification among children and adolescents. What is New: • The magnitude of BP change among children and adolescents is highly affected by BP level and age. • BP does not always drop on consecutive measurements, and evidence-based BP assessment protocols should be established to avoid misdiagnosis of hypertension.
Publisher: Springer Science and Business Media LLC
Date: 03-10-2019
DOI: 10.1038/S41371-019-0266-Z
Abstract: Hypertension is the most common circulatory system condition, accounting for >40% of the cardiovascular disease total burden. One-third of Australians aged over 18 years have hypertension and in 68% of these it is uncontrolled. Australian data show hypertension accounts for 6% of general practitioner (GP) consults. Recent evidence has confirmed exercise is an effective adjunct therapy for hypertension management and the objective of this document is to provide a contemporary, evidence-based guide for optimal delivery of an exercise programme for blood pressure management. This work is an update to the 2009 Exercise and Sport Science Australia (ESSA) position stand. In most cases, the first line treatment to reduce BP is initiation of lifestyle changes, of which regular aerobic exercise is a principal component. Aerobic and resistance activities remain the cornerstone of exercise-based management of blood pressure, but recent work has uncovered variations on traditional delivery of exercise, such as high intensity interval training (HIIT) and a new exercise modality, isometric resistance training (IRT) may offer alternative management regimens. Exercise Physiologists, as well as other health care professionals, play an important role in helping to achieve BP control in patients with hypertension by reinforcing healthy lifestyle habits and prescribing appropriate exercise.
Publisher: Wiley
Date: 10-02-2021
DOI: 10.1111/AJAG.12911
Abstract: This study aimed to develop and test the feasibility of using an electronic tool to ascertain falls and their circumstances (TASeFALL) in people aged over 60 years. Forty participants (mean age: 69.3 ± 5.4 years, 55% women) were randomised to receive a monthly paper‐based questionnaire (control group n = 19), compared with the same questionnaire sent via email with LimeSurvey software (TASeFALL n = 21). Falls and their circumstances were recorded prospectively over 12 months in all participants. The main outcomes were feasibility of enrolment, number of falls, adherence to completion of questionnaires and cost. The incidence, number of falls and adherence to the completion of the questionnaire over the 12‐month follow‐up were similar in both the TASeFALL and control groups. However, the monthly paper‐based questionnaire approach was 45% more expensive. The TASeFALL is a feasible and cost‐effective method of falls ascertainment for older people with email access that could have a wide research uptake.
Publisher: Springer Science and Business Media LLC
Date: 2015
Publisher: Springer Science and Business Media LLC
Date: 28-03-2013
DOI: 10.1038/JHH.2013.23
Abstract: Blood pressure (BP) is conventionally measured by cuff at the brachial artery as an indication of pressure experienced by the organs. However, in idual variation in pulse pressure lification means that brachial cuff BP may be a poor representation of true central BP. Estimation of central BP is now possible using non-invasive methods that are amenable for widespread use. This paper reviews the evidence regarding the potential value of central BP in hypertension management. The major lines of evidence that support the use of central BP as a clinical tool include the: (1) major discrepancies in central BP among people with similar brachial BP (2) independent relationship of central BP with end-organ damage (3) independent relationship of central BP with cardiovascular (CV) events and mortality (4) differential central and brachial BP responses to antihypertensive medications and (5) improvements in end-organ damage after therapy more strongly relate to central than brachial BP. Despite all this, important evidence gaps relating to clinical use of central BP need fulfilling. These include the lack of central BP reference values and randomized, controlled studies to determine if: (1) central BP can help with diagnostic/therapeutic decisions and (2) CV outcome is improved by targeting therapy towards lowering central BP levels. Additional challenges such as standardization of central BP methods, and understanding which patients are most likely to benefit from central BP monitoring also need to be determined. Overall, the future for central BP as a worthwhile clinical instrument appears positive, but there is much to be done.
Publisher: Pan American Health Organization
Date: 15-07-2020
Abstract: La hipertensión arterial es una causa modificable muy prevalente de enfermedades cardiovasculares, accidentes cerebrovasculares y muerte. Medir con exactitud la presión arterial es fundamental, dado que un error de medición de 5 mmHg puede ser motivo para clasificar incorrectamente como hipertensas a 84 millones de personas en todo el mundo. En la presente declaración de posición se resumen los procedimientos para optimizar el desempeño del observador al medir la presión arterial en el consultorio, con atención especial a los entornos de ingresos bajos o medianos, donde esta medición se ve complicada por limitaciones de recursos y tiempo, sobrecarga de trabajo y falta de suministro eléctrico. Es posible reducir al mínimo muchos errores de medición con una preparación adecuada de los pacientes y el uso de técnicas estandarizadas. Para simplificar la medición y prevenir errores del observador, deben usarse tensiómetros semiautomáticos o automáticos de manguito validados, en lugar del método por auscultación. Pueden ayudar también la distribución de tareas, la creación de un área específica de medición y el uso de aparatos semiautomáticos o de carga solar. Es fundamental garantizar la capacitación inicial y periódica de los integrantes del equipo de salud. Debe considerarse la implementación de programas de certificación de bajo costo y fácilmente accesibles con el objetivo de mejorar la medición de la presión arterial.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 02-2021
DOI: 10.1161/HYPERTENSIONAHA.120.16109
Abstract: Isolated systolic hypertension (ISH) is the most common form of hypertension and is highly prevalent in older people. We recently showed differences between upper-arm cuff and invasive blood pressure (BP) become greater with increasing age, which could influence correct identification of ISH. This study sought to determine the difference between identification of ISH by cuff BP compared with invasive BP. Cuff BP and invasive aortic BP were measured in 1695 subjects (median 64 years, interquartile range [55–72], 68% male) from the INSPECT (Invasive Blood Pressure Consortium) database. Data were recorded during coronary angiography among 29 studies, using 21 different cuff BP devices. ISH was defined as ≥130/ mm Hg using cuff BP compared with invasive aortic BP as the reference. The prevalence of ISH was 24% (n=407) according to cuff BP but 38% (n=642) according to invasive aortic BP. There was fair agreement (Cohen κ, 0.36) and 72% concordance between cuff and invasive aortic BP for identifying ISH. Among the 28% of subjects (n=471) with misclassification of ISH status by cuff BP, 20% (n=96) of the difference was due to lower cuff systolic BP compared with invasive aortic systolic BP (mean, −16.4 mm Hg [95% CI, −18.7 to −14.1]), whereas 49% (n=231) was from higher cuff diastolic BP compared with invasive aortic diastolic BP (+14.2 mm Hg [95% CI, 11.5−16.9]). In conclusion, compared with invasive BP, cuff BP fails to identify ISH in a sizeable portion of older people and demonstrates the need to improve cuff BP measurements.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 06-2018
Publisher: American Physiological Society
Date: 08-2018
DOI: 10.1152/AJPENDO.00448.2017
Abstract: Skeletal muscle microvascular (capillary) blood flow increases in the postprandial state or during insulin infusion due to dilation of precapillary arterioles to augment glucose disposal. This effect occurs independently of changes in large artery function. However, acute hyperglycemia impairs vascular function, causes insulin to vasoconstrict precapillary arterioles, and causes muscle insulin resistance in vivo. We hypothesized that acute hyperglycemia impairs postprandial muscle microvascular perfusion, without disrupting normal large artery hemodynamics, in healthy humans. Fifteen healthy people (5 F/10 M) underwent an oral glucose challenge (OGC, 50 g glucose) and a mixed-meal challenge (MMC) on two separate occasions (randomized, crossover design). At 1 h, both challenges produced a comparable increase (6-fold) in plasma insulin levels. However, the OGC produced a 1.5-fold higher increase in blood glucose compared with the MMC 1 h postingestion. Forearm muscle microvascular blood volume and flow (contrast-enhanced ultrasound) were increased during the MMC (1.3- and 1.9-fold from baseline, respectively, P 0.05 for both) but decreased during the OGC (0.7- and 0.6-fold from baseline, respectively, P 0.05 for both) despite a similar hyperinsulinemia. Both challenges stimulated brachial artery flow (ultrasound) and heart rate to a similar extent, as well as yielding comparable decreases in diastolic blood pressure and total vascular resistance. Systolic blood pressure and aortic stiffness remained unaltered by either challenge. Independently of large artery hemodynamics, hyperglycemia impairs muscle microvascular blood flow, potentially limiting glucose disposal into skeletal muscle. The OGC reduced microvascular blood flow in muscle peripherally and therefore may underestimate the importance of skeletal muscle in postprandial glucose disposal.
Publisher: Japan Atherosclerosis Society
Date: 2010
DOI: 10.5551/JAT.2683
Abstract: Central pulse pressure and measures of arterial stiffness (augmentation index (AIx) and aortic pulse wave velocity (PWV)) predict morbidity and mortality in patients with stage 2-4 chronic kidney disease (CKD). Although statin therapy may be of vascular benefit in patients with CKD, the long-term effect of statins on central pulse pressure and arterial stiffness has not been assessed in this patient population. Hence, the aim of this study was to assess the long-term effects of atorvastatin on arterial stiffness and central blood pressure in patients with CKD. We enrolled 37 patients with serum creatinine levels > 1.36 mg/dL into a randomized, double blind trial. Patients were allocated to receive 10 mg of atorvastatin per day (19) or placebo (18) for three years. Aortic PWV, AIx, estimated central and brachial blood pressures and were determined every nine months. At baseline, there were no significant differences in aortic PWV, AIx, central or brachial blood pressures between atorvastatin-treated and placebo-treated patients. During the trial, aortic PWV significantly (p=0.05) increased in placebo-treated, but not (p=0.10) in atorvastatin-treated patients (0.51+/-0.95 vs. 0.30+/-0.75 m/sec/yr p=0.48). This represented a 41% (but not statistically significant) slowing of the rate of increase in aortic stiffness. There were no significant changes between groups in the rate of change of AIx (atorvastatin -0.15+/-5.65 vs. placebo 0.39+/-5.38%/yr, p=0.53) or central pulse pressure (atorvastatin -2.32+/-7.46 vs. placebo -0.36+/-6.64 mmHg/yr p= 0.61). In patients with CKD arterial stiffness measured by aortic PWV showed a significant increase over time in placebo-treated patients but not in atorvastatin-treated patients.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 28-07-2020
Publisher: Springer Science and Business Media LLC
Date: 2017
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 13-09-2023
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 09-2019
Publisher: Springer Science and Business Media LLC
Date: 29-01-2009
Abstract: Exercise training in hemodialysis patients improves fitness, physical function, quality of life and markers of cardiovascular disease such as arterial stiffness. The majority of trials investigating this area have used supervised exercise training during dialysis (intradialytic), which may not be feasible for some renal units. The aim of this trial is to compare the effects of supervised intradialytic with unsupervised home-based exercise training on physical function and arterial stiffness. This is a randomised, controlled clinical trial. A total of 72 hemodialysis patients will be randomised to receive either six months of intradialytic exercise training, home-based exercise training or usual care. Intradialytic patients will undergo three training sessions per week on a cycle ergometer and home-based patients will be provided with a walking program to achieve the same weekly physical activity. Primary outcome measures are six-minute walk distance (6 MWD) and aortic pulse wave velocity (PWV). Secondary outcome measures include augmentation index, peripheral and central blood pressures, physical activity and self-reported health. Measures will be made at baseline, three and six months. The results of this study will help determine the efficacy of home-based exercise training in hemodialysis patients. This may assist in developing exercise guidelines specific for these patients. ACTRN12608000247370
Publisher: Elsevier BV
Date: 11-2014
DOI: 10.1016/J.ATHEROSCLEROSIS.2014.08.029
Abstract: The independent prognostic significance of abnormally low systolic blood pressure (SBP) during exercise stress testing (LowExBP) across different clinical and exercise conditions is unknown. We sought by systematic review and meta-analysis to determine the association between cardiovascular/all-cause outcomes and LowExBP across different patient clinical presentations, exercise modes, exercise intensities and categories of LowExBP. Seven online databases were searched for longitudinal studies reporting the association of LowExBP with risk of fatal and non-fatal cardiovascular events and/or all-cause mortality. LowExBP was defined as either: SBP drop below baseline failure to increase >10 mmHg from baseline or lowest SBP quantile among reporting studies. After review of 13,257 studies, 19 that adjusted for resting SBP were included in the meta-analysis, with a total of 45,895 participants (average follow-up, 4.4 ± 3.0 years). For the whole population, LowExBP was associated with increased risk for fatal and non-fatal cardiovascular events and all-cause mortality (hazard ratio [HR]: 2.01, 95% confidence interval [CI]: 1.59-2.53, p < 0.001). In continuous analyses, a 10 mmHg decrease in exercise SBP was associated with higher risk (n = 9 HR: 1.13, 95% CI: 1.06-1.20, p < 0.001). LowExBP was associated with increased risk regardless of clinical presentation (coronary artery disease, heart failure, hypertrophic cardiomyopathy or peripheral artery disease), exercise mode (treadmill or bike), exercise intensity (moderate or maximal), or LowExBP category (all p < 0.05). However, bias toward positive results was apparent (Eggers test p < 0.001 and p = 0.009). Our data show that irrespective of clinical or exercise conditions, LowExBP independently predicts fatal and non-fatal cardiovascular events and all-cause mortality.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 06-2014
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 02-07-2019
Abstract: Reservoir‐wave approach is an alternative model of arterial hemodynamics based on the assumption that measured arterial pressure is composed of volume‐related (reservoir pressure) and wave‐related components (excess pressure). However, the clinical utility of reservoir‐wave approach remains debatable. In a single‐center cohort of 260 dialysis patients, we examined whether carotid and radial reservoir‐wave parameters were associated with all‐cause and cardiovascular mortality. Central pulse pressure and augmentation index at 75 beats per minute were determined by radial arterial tonometry through generalized transfer function. Carotid and radial reservoir‐wave analysis were performed to determine reservoir pressure and excess pressure integral. After a median follow‐up of 32 months, 171 (66%) deaths and 88 (34%) cardiovascular deaths occurred. In Cox regression analysis, carotid excess pressure integral was associated with a hazard ratio of 1.33 (95% CI , 1.14–1.54 P .001 per 1 SD) for all‐cause and 1.45 (95% CI : 1.18–1.75 P .001 per 1 SD) for cardiovascular mortality. After adjustments for age, heart rate, sex, clinical characteristics and carotid‐femoral pulse wave velocity, carotid excess pressure integral was consistently associated with increased risk of all‐cause (hazard ratio per 1 SD, 1.30 95% CI : 1.08–1.54 P =0.004) and cardiovascular mortality (hazard ratio per 1 SD, 1.31 95% CI : 1.04–1.63 P =0.019). Conversely, there were no significant associations between radial reservoir‐wave parameters, central pulse pressure, augmentation index at 75 beats per minute, pressure forward, pressure backward and reflection magnitude, and all‐cause or cardiovascular mortality after adjustment for comorbidities. These observations support the clinical value of reservoir‐wave approach parameters of large central elastic vessels in end‐stage renal disease.
Publisher: Springer Science and Business Media LLC
Date: 08-10-2015
DOI: 10.1038/JHH.2015.101
Abstract: Brachial-to-radial-systolic blood pressure lification (Bra-Rad-SBPAmp) can affect central SBP estimated by radial tonometry. Patients with type 2 diabetes mellitus (T2DM) have vascular irregularities that may alter Bra-Rad-SBPAmp. By comparing T2DM with non-diabetic controls, we aimed to determine the (1) magnitude of Bra-Rad-SBPAmp (2) haemodynamic factors related to Bra-Rad-SBPAmp and (3) effect of Bra-Rad-SBPAmp on estimated central SBP. Twenty T2DM (64±8 years) and 20 non-diabetic controls (60±8 years 50% male both) underwent simultaneous cuff deflation and two-dimensional ultrasound imaging of the brachial and radial arteries. The first Korotkoff sound (denoting SBP) was identified from the first inflection point of Doppler flow during cuff deflation. Bra-Rad-SBPAmp was calculated by radial minus brachial SBP. Upper limb and systemic haemodynamics were recorded by tonometry and ultrasound. Radial SBP was higher than brachial SBP for T2DM (136±19 vs 127±17 mm Hg P<0.001) and non-diabetic controls (135±12 vs 121±11 mm Hg P<0.001), but Bra-Rad-SBPAmp was significantly lower in T2DM (9±8 vs 14±7 mm Hg P=0.042). The product of brachial mean flow velocity × brachial diameter was inversely and independently correlated with Bra-Rad-SBPAmp in T2DM (β=-0.033 95% confidence interval -0.063 to -0.004, P=0.030). When radial waveforms were calibrated using radial, compared with brachial SBP, central SBP was significantly higher in both groups (T2DM, 116±13 vs 125±15 mm Hg and controls, 112±10 vs 124±11 mm Hg P<0.001 both) and there was a significant increase in the number of participants classified with 'central hypertension' (SBP⩾130 mm Hg P=0.004). Compared with non-diabetic controls, Bra-Rad-SBPAmp is significantly lower in T2DM. Regardless of disease status, radial SBP is higher than brachial SBP and this results in underestimation of central SBP using brachial-BP-calibrated radial tonometry.
Publisher: Elsevier BV
Date: 02-2005
DOI: 10.1016/J.AMJCARD.2004.09.047
Abstract: The nongenomic effects of aldosterone in disease states associated with endothelial dysfunction may differ from those in healthy subjects. The effects of locally infused aldosterone on the forearm blood flow and volume were studied in optimally treated patients with chronic heart failure (CHF). At baseline and after incremental intrabrachial aldosterone, forearm blood flow was assessed using conventional strain gauge plethysmography, and forearm venous volume was assessed by radionuclide plethysmography. Constriction of the resistance vasculature of the forearm without significant effect on forearm venous capacitance was demonstrated in response to aldosterone in patients treated for CHF.
Publisher: Springer Science and Business Media LLC
Date: 23-03-2022
Publisher: BMJ
Date: 03-2014
Publisher: Springer Science and Business Media LLC
Date: 23-03-2006
Publisher: Springer Science and Business Media LLC
Date: 30-05-2022
DOI: 10.1038/S41371-022-00693-X
Abstract: Automated ‘oscillometric’ blood pressure (BP) measuring devices (BPMDs) were developed in the 1970s to replace manual auscultatory BP measurement by mercury sphygmomanometer. Automated BPMDs that have passed accuracy testing versus a reference auscultatory sphygmomanometer using a scientifically accepted validation protocol are recommended for clinical use globally. Currently, there are many thousands of unique automated BPMDs manufactured by hundreds of companies, with each device using proprietary algorithms to estimate BP and using a method of operation that is largely unchanged since inception. Validated automated BPMDs provide similar BP values to those recorded using manual auscultation albeit with potential sources of error mostly associated with using empirical algorithms to derive BP from waveform pulsations. Much of the work to derive contemporary BP thresholds and treatment targets used to manage cardiovascular disease risk was obtained using automated BPMDs. While there is room for future refinement to improve accuracy for better in idual risk stratification, validated BPMDs remain the recommended standard for office and out-of-office BP measurement to be used in hypertension diagnosis and management worldwide.
Publisher: SAGE Publications
Date: 17-10-2021
DOI: 10.1177/0310057X211002838
Abstract: Prophylactic administration of uterotonics ensures adequate uterine contraction at elective caesarean section to prevent substantial haemorrhage. Royal College of Obstetricians and Gynaecologists guidelines advise the administration of oxytocin at 5 IU as a ‘slow bolus’ but there are variations in clinical practice. This study aimed to determine the beliefs and uterotonic usage practices at elective caesarean section by surveying anaesthetist members of the Obstetric Anaesthesia Special Interest Group in Australia and New Zealand. Questionnaires were emailed to Obstetric Anaesthesia Special Interest Group members and the response rate was 33%, with analysis of 279 completed reports. Oxytocin was the most commonly used first-line uterotonic, but extensive variation in oxytocin bolus use was identified. Thirty-eight per cent of anaesthetists routinely administered Royal College of Obstetricians and Gynaecologists guideline-recommended 5 IU, whereas 38% favoured low dose ( IU), 10% high dose (≥10 IU) oxytocin and 13% carbetocin (100 µg). More than 50% felt the evidence was weak for guideline-recommended 5 IU. Wide variation in the duration of oxytocin administration was also identified. Fifty-eight per cent of anaesthetists routinely gave follow-up oxytocin infusions, most commonly at 40 IU over 4 hours, but there was significant variation in the dosage (10–40 IU) and administration duration (1 hour to ≥6 hours). In conclusion, there is significant variation in oxytocin usage practices at elective caesarean section among Australian and New Zealand anaesthetists. This variation may be due to a lack of strong evidence to guide practice. This emphasises the need for high quality trials in this clinically important area.
Publisher: Elsevier BV
Date: 09-2021
Publisher: Springer Science and Business Media LLC
Date: 13-11-2018
DOI: 10.1038/S41371-018-0124-4
Abstract: Due to systolic blood pressure (SBP) lification, brachial SBP may not accurately reflect central SBP, the pressure the organs are exposed to. Patients with type 2 diabetes (T2D) have vascular irregularities that may affect blood pressure (BP) lification and central BP indices (i.e. augmentation index [AIx] and augmentation pressure [AP]). By systematic review and meta-analysis, this study aimed firstly to determine the magnitude of central-to-brachial SBP and pulse pressure (PP) lification in T2D compared to healthy controls and secondly, the difference in AIx and AP between the groups. Online databases were searched for published studies reporting invasive or non-invasive central and brachial SBP in T2D and healthy controls up to the 20th of February 2018. Random effects meta-analyses and meta-regression were used to analyze the studies. Eighteen studies (all non-invasive: 17 radial tonometry, 1 carotid tonometry, 2 brachial oscillometry) with a total of 2758 patients with T2D and 10,561 healthy controls were identified. There was no significant difference in SBP lification between groups (T2D = 9.9 ± 4.7, healthy controls = 9.6 ± 4.5 mmHg, p = 0.84 pooled difference = 0.64 mmHg, 95%CI -0.27 1.54, p = 0.17) or PP lification ratio (p = 0.16). However, among these studies, central BP indices (AIx corrected for heart rate and AP) were significantly higher in T2D (p < 0.05 for both). Despite a similar magnitude of central-to-brachial SBP lification, patients with T2D have increased central systolic loading (AIx and AP) that cannot be discerned from brachial BP alone.
Publisher: Oxford University Press (OUP)
Date: 02-2011
DOI: 10.1038/AJH.2010.230
Publisher: Springer Science and Business Media LLC
Date: 2013
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 07-2020
Publisher: Oxford University Press (OUP)
Date: 10-10-2015
DOI: 10.1093/AJH/HPU191
Abstract: Evidence for the benefits of regular exercise is irrefutable and increasing physical activity levels should be a major goal at all levels of health care. People with hypertension are less physically active than those without hypertension and there is strong evidence supporting the blood pressure-lowering ability of regular exercise, especially in hypertensive in iduals. This narrative review discusses evidence relating to exercise and cardiovascular (CV) risk in people with hypertension. Comparisons between aerobic, dynamic resistance, and static resistance exercise have been made along with the merit of different exercise volumes. High-intensity interval training and isometric resistance training appear to have strong CV protective effects, but with limited data in hypertensive people, more work is needed in this area. Screening recommendations, exercise prescriptions, and special considerations are provided as a guide to decrease CV risk among hypertensive people who exercise or wish to begin. It is recommended that hypertensive in iduals should aim to perform moderate intensity aerobic exercise activity for at least 30 minutes on most (preferably all) days of the week in addition to resistance exercises on 2-3 days/week. Professionals with expertise in exercise prescription may provide additional benefit to patients with high CV risk or in whom more intense exercise training is planned. Despite lay and media perceptions, CV events associated with exercise are rare and the benefits of regular exercise far outweigh the risks. In summary, current evidence supports the assertion of exercise being a cornerstone therapy in reducing CV risk and in the prevention, treatment, and control of hypertension.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 05-2020
DOI: 10.1161/ATVBAHA.120.314102
Abstract: Impaired baroreflex function is an early indicator of cardiovascular autonomic imbalance. Patients with type 2 diabetes mellitus (T2D) have decreased baroreflex sensitivity (BRS), however, whether the neural and/or mechanical component of the BRS (nBRS and mBRS, respectively) is altered in those with high metabolic risk (HMR, impaired fasting glucose and/or metabolic syndrome) or with overt T2D, is unknown. We examined this in a community-based observational study, the Paris Prospective Study III (PPS3). In 7626 adults aged 50 to 75 years, resting nBRS (estimated by low-frequency gain, from carotid distension rate and RR intervals [time intervals between successive R waves]) and mBRS were measured by high-precision carotid echotracking. The associations between overt T2D or HMR as compared with subjects with normal glucose metabolism (NGM) and nBRS or mBRS were quantified using multivariable linear regression analysis. There were 319 subjects with T2D (61±6 years, 77% male), 1450 subjects with HMR (60±6 years, 72% male), and 5857 subjects with NGM (59±6 years, 57% male). Compared with NGM subjects, nBRS was significantly lower in HMR subjects (β=−0.07 [95% CI, −0.12 to −0.01] P =0.029) and in subjects with T2D (β=−0.18 [95% CI, −0.29 to −0.07] P =0.002) after adjustment for confounding and mediating factors. Subgroup analysis suggests significant and independent alteration in mBRS only among HMR patients who had both impaired fasting glucose and metabolic syndrome. In this community-based study of in iduals aged 50 to 75, a graded decrease in nBRS was observed in HMR subjects and patients with overt T2D as compared with NGM subjects.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 07-10-2022
Publisher: Elsevier BV
Date: 2010
DOI: 10.1053/J.AJKD.2009.09.025
Abstract: Hemodialysis patients show reduced physical function and greater risk of increased arterial stiffness because of hypertension, metabolic disturbances, and vascular calcification. Exercise interventions potentially could improve their vascular risk profile. Randomized controlled pilot clinical study comparing the effects of 6 months of supervised intradialytic exercise training versus home-based exercise training or usual care on physical function and arterial stiffness in hemodialysis patients. 70 hemodialysis patients from 3 renal units. Intradialytic-exercise patients trained 3 times/wk for 6 months on a cycle ergometer and home-based-exercise patients followed a walking program to achieve the same weekly physical activity. Usual-care patients received no specific intervention. Primary outcome measures were distance traveled during a 6-minute walk test and aortic pulse wave velocity. Secondary outcome measures included augmentation index (augmentation pressure as a percentage of central pulse pressure), peripheral (brachial) and central blood pressures (measured noninvasively using radial tonometry), physical activity, and self-reported physical functioning. Measurements were made at baseline and 6 months. At 6 months, there were no significant differences between changes in 6-minute walk test distance (intradialytic exercise, +14% home-based exercise, +11% usual care, +5%), pulse wave velocity (intradialytic exercise, -4% home-based exercise, -2% usual care, +5%), or any secondary outcome measure. Lack of medication data limited the analysis of vascular parameters in this study. There were no differences between intradialytic or home-based exercise training and usual care for either physical function or vascular parameters.
Publisher: Elsevier BV
Date: 03-2007
DOI: 10.1016/J.AMJCARD.2006.10.045
Abstract: Left ventricular (LV) diastolic dysfunction and increased arterial stiffness are prevalent in patients with type 2 diabetes mellitus (DM). Because the systemic vasculature plays a pivotal role in myocardial loading, this study aimed to determine the effect of arterial characteristics on LV diastolic function in patients with type 2 DM. Conventional echocardiography and tissue Doppler imaging were performed in 155 patients with type 2 DM (88 men mean age 55 +/- 11 years) with preserved LV ejection fractions (>50%). Patients were stratified into groups on the basis of LV diastolic function (normal, n = 53 delayed relaxation, n = 79 pseudonormal, n = 23). Arterial wave reflection parameters and central blood pressure were determined by radial tonometry. Arterial (brachial and carotid) structure and function were determined by standard ultrasound methods. There were no significant differences among the groups on central pressure or arterial function. LV filling pressure, determined by the ratio of early transmitral inflow velocity to diastolic early tissue velocity (E/E'), was significantly correlated with central pulse pressure (r = 0.21, p <0.05). Late diastolic inflow velocity (A) was significantly associated with central pulse pressure (r = 0.32, p <0.001), total arterial compliance (r = -0.35, p <0.001), and carotid artery stiffness (r = 0.34, p <0.001). Multiple regression analysis found central but not brachial pulse pressure independently predicted E/E' and A. In conclusion, increased central pulse pressure, possibly due to lified pressure wave reflections, is independently associated with abnormal LV diastolic function in patients with type 2 DM.
Publisher: Springer Science and Business Media LLC
Date: 2008
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 08-2016
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 07-2008
Publisher: MDPI AG
Date: 28-02-2022
Abstract: High blood pressure (BP) is a leading risk factor for cardiovascular disease (CVD). The identification of high BP is conventionally based on in-clinic (resting) BP measures, performed within primary health care settings. However, many cases of high BP go unrecognised or remain inadequately controlled. Thus, there is a need for complementary settings and methods for BP assessment to identify and control high BP more effectively. Exaggerated exercise BP is associated with increased CVD risk and may be a medium to improve identification and control of high BP because it is suggestive of high BP gone undetected on the basis of standard in-clinic BP measures at rest. This paper provides the evidence to support a pathway to aid identification and control of high BP in clinical exercise settings via the measurement of exercise BP. It is recommended that exercise professionals conducting exercise testing should measure BP at a fixed submaximal exercise workload at moderate intensity (e.g., ~70% age-predicted heart rate maximum, stage 1–2 of a standard Bruce treadmill protocol). If exercise systolic BP is raised (≥170 mmHg), uncontrolled high BP should be assumed and should trigger correspondence with a primary care physician to encourage follow-up care to ascertain true BP control (i.e., home, or ambulatory BP) alongside a hypertension-guided exercise and lifestyle intervention to lower CVD risk related to high BP.
Publisher: Wiley
Date: 04-2020
DOI: 10.1111/SMS.13645
Abstract: Exaggerated exercise blood pressure (BP) is associated with altered cardiac structure and increased cardiovascular risk. Fitness modifies these associations, but the effect in healthy adolescents is unknown. We performed an observational study to determine the influence of fitness on post‐exercise BP, and on its relationship with cardiac structure in adolescents. 4835 adolescents from the Avon Longitudinal Study of Parents and Children, (15.4 (0.3) years, 49% male) completed a submaximal cycle test. Fitness was estimated as physical work capacity 170 adjusted for lean body mass and post‐exercise BP measured immediately posttest. Cardiovascular structure and function, including left ventricular (LV) mass (n = 1589), left atrium (LA) size (n = 1466), cardiac output (CO, n = 1610), and total peripheral resistance (TPR, n = 1610) were measured at rest by echocardiography 2.4 (0.4) years later. Post‐exercise systolic BP increased stepwise by fitness tertile (131.2 mm Hg [130.4, 132.1] 137.3 mm Hg [136.5, 138.0] 142.3 mm Hg [141.5, 143.1]). Each 5 mm Hg of post‐exercise systolic BP was associated with 2.46 g [1.91, 3.01] greater LV mass, 0.02 cm [0.02, 0.03] greater LA size, and 0.25 g/m 2.7 [0.14, 0.36] greater LV mass index. Adjustment for fitness abolished associations (0.29 g [−0.16, 0.74] 0.01 cm [−0.001, 0.014] and 0.08 g/m 2.7 [−0.001, 0.002]). Similar associations between post‐exercise systolic BP and each outcome were found between the lowest and highest fitness thirds. CO increased with fitness third (difference 0.06 L/min [−0.05, 0.17] 0.23 L/min [0.12, 0.34]) while TPR decreased (difference −0.13 mm Hg·min/L [−0.84,0.59] −1.08 mm Hg·min/L [−0.1.80, 0.35]). Post‐exercise systolic BP increased with fitness, which modified its association with cardiac structure. Higher CO, but lower TPR suggests a physiologically adapted cardiovascular system with greater fitness, highlighting the importance of fitness in adolescence.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 11-2018
DOI: 10.1161/HYPERTENSIONAHA.118.11442
Abstract: Vascular aging is a major contributor to cardiovascular disease and can be quantified by higher carotid stiffness, intima-media thickness and diameter, and hypertension. Weight gain across the lifetime may be an important, modifiable determinant of vascular aging. We therefore aimed to assess lifetime body silhouette trajectories (a marker of weight change across the lifespan) in relation to vascular aging in late adulthood. We used cross-sectional data from a community-based cohort study (n=8243 age, 59.4 38.7% women). A linear mixed model was used to assess trajectories of recalled body silhouettes from age 8 to 45 years. We assessed carotid artery properties (ultrasonography), resting hypertension (blood pressure ≥140/90 mm Hg or use of antihypertensives), and exaggerated exercise blood pressure, a marker of masked hypertension (systolic blood pressure ≥150 mm Hg during submaximal exercise) at study recruitment when the participants were 50 to 75 years of age. We identified 5 distinct body silhouette trajectories: lean stable (32.0%), lean increase (11.1%), moderate stable (32.5%), lean-marked increase (16.3%), and heavy stable (8.1%). Compared with in iduals in the lean-stable trajectory, those in the moderate-stable, lean-marked increase, and heavy-stable trajectories had higher carotid stiffness, intima-media thickness and diameter (odds ratios between 1.23 and 2.10 for highest quartile versus lowest quartile of manifestations of vascular aging P .05) and were more likely to have resting hypertension and exaggerated exercise blood pressure, after adjustment for potential confounders (odds ratios between 1.31 and 1.60 P .05). Vascular aging was most prominent among in iduals who were lean in early life but markedly gained weight during young adulthood and among those who were heavy in early life and maintained weight.
Publisher: Elsevier BV
Date: 05-2012
DOI: 10.1016/J.AHJ.2012.02.017
Abstract: Noninvasive estimates of central blood pressure (BP) predict cardiovascular morbidity and mortality independent of brachial BP. However, there are limited data on the usefulness of central BP in clinical practice. This study aims to test the value of central BP as a management tool for physicians treating patients with essential hypertension. Participants with uncomplicated essential hypertension (N = 284) will be randomized to 12 months of treatment decisions guided by usual care (based on office, home, and 24-hour ambulatory brachial BP) or, in addition, by central BP estimated using radial tonometry (based on age- and sex-specific normal central systolic BP values). Recommendations regarding titration of antihypertensive medication (increase, decrease, or maintain dose) will be provided to each participant's general practitioner as well as the participant themselves. Relevant clinical information (eg, comorbidities, left ventricular [LV] mass, blood biochemistry, and BP-related symptoms) will be considered when making titration recommendations in all participants. The primary outcome measures will be (1) change in LV mass (by real-time 3-dimensional echocardiography), (2) amount of medication used, and (3) quality of life. Analysis will be by intention to treat. It is expected that there will be no significant difference in LV mass between groups. However, it is hypothesized that there will be significantly reduced use of medication and improved quality of life in the central BP group because more appropriate titration choices will be made to maintain normal central systolic BP. Results are expected in 2012.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 04-2008
DOI: 10.1161/HYPERTENSIONAHA.107.102558
Abstract: NO modulates resting blood pressure and wave reflection. The effect of NO on exercise central hemodynamics is unknown but has important implications relating to cardiovascular risk. The aim of this study was to determine the contribution of NO to pulse pressure (PP) lification and wave reflection during exercise. Twelve healthy men aged 29±1 years (mean±SEM) undertook cycle exercise at 60% of their maximal heart rate. Noninvasive measures of central blood pressure, estimated aortic pulse wave velocity, and wave reflection (augmentation index) were obtained by pulse wave analysis during intravenous infusion of saline (control), N G -monomethyl- l -arginine (a NO-synthase inhibitor), or noradrenaline (control vasoconstrictor). PP lification was defined as the ratio of peripheral to central PP. Cardiac output and stroke volume were determined by electric bioimpedance. Both N G -monomethyl- l -arginine and noradrenaline caused a significant increase in mean arterial pressure ( P .01) and augmentation index ( P .01), as well as reduced ratio of peripheral to central PP ( P .05) at baseline. Exercise caused a significant increase in the ratio of peripheral to central PP ( P .001), whereas augmentation index and estimated aortic pulse wave velocity declined (for both P .05) during all 3 of the infusion protocols. However, no significant differences were observed in augmentation index, ratio of peripheral to central PP, or estimated aortic pulse wave velocity between infusion procedures ( P .50) during exercise. Also, heart rate, peripheral vascular resistance, and cardiac output did not differ during exercise between saline, N G -monomethyl- l -arginine, or noradrenaline. Although we cannot rule out other vasodilator mechanisms having adjusted for NO blockade, our results indicate that NO does not solely contribute to systemic arterial stiffness or altered blood pressure lification during light exercise.
Publisher: Oxford University Press (OUP)
Date: 08-2018
Publisher: Elsevier BV
Date: 2009
DOI: 10.1016/J.IJCARD.2008.03.049
Abstract: Patients with coronary slow flow (CSF) present with a syndrome (often recurrent) of resting angina with no significant coronary stenoses. The nature of myocardial blood flow (MBF), MBF reserve and systemic arterial characteristics may contribute to symptoms in these patients but this has not been examined previously. This study sought to measure MBF, arterial stiffness and wave reflection in patients with CSF and controls. Ten patients with angiographically proven CSF and 20 controls underwent dipyridamole-exercise stress myocardial contrast echocardiography and arterial waveform analysis. MBF was quantified off-line from 10 mid and apical segments with calculation of myocardial blood volume (A), red cell velocity (beta) and their product, MBF, at rest and post-stress. MBF reserve was calculated as the ratio of peak stress to resting MBF. Central arterial pressure waveforms were derived by radial tonometry, with arterial wave reflection expressed by augmentation index. Arterial stiffness was determined by aortic and brachial pulse wave velocities. There was no significant difference between CSF and control groups in mean resting beta (0.56+/-0.24 versus 0.59+/-0.26), A (7.9+/-1.4 versus 7.9+/-5.2), MBF (4.3+/-1.8 versus 4.4+/-3.6), MBF reserve (3.7+/-2.0 versus 4.0+/-2.0), augmentation index (26+/-12 versus 23+/-9%), aortic (7.4+/-1.8 versus 7.4+/-1.5 m/s) or brachial (8.0+/-0.8 versus 8.1+/-1.3) pulse wave velocity (p>0.4 for all). Similarly, there were no significant haemodynamic differences between groups after exercise (p>0.2 for all). MBF, large artery stiffness and arterial wave reflection characteristics are normal in CSF patients between their acute episodes.
Publisher: Springer Science and Business Media LLC
Date: 12-2008
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 11-2009
DOI: 10.1161/HYPERTENSIONAHA.109.133066
Abstract: Augmentation index (AIx), a correlate of mortality, is thought to be influenced by left ventricular contractility and wave reflections. However, the relationship of AIx with left ventricular contractility changes has never been assessed, and the wave reflection theory has recently been questioned. This study sought to examine arterial waveform changes in response to reduced “wave reflection” and increased left ventricular contractility induced by dobutamine. Simultaneous radial tonometry (for AIx) and tissue Doppler echocardiography (for peak longitudinal systolic strain rate [SR] as an analogue of left ventricular contractility) were recorded at rest and peak dobutamine-induced stress in 50 patients (41 men aged 62±10 years). From baseline to peak stress there was an increase in heart rate (70±11 to 127±17 bpm P .001) and SR (−0.88±0.23 to −1.81±0.43 1/s P .001), whereas AIx decreased (27±9% to −7±15% P .001). There was also a greater increase in the systolic (compared with diastolic) pressure-time integral relative to cardiac cycle length (3.2±1.9 versus 1.8±1.1 mm Hg P .001), indicating that wave reflection was not shifted into diastole as per the current belief. AIx was significantly associated with ejection duration ( r =0.88), heart rate ( r =−0.81), and SR ( r =0.72 P .001 for all). However, when SR was heart rate corrected, there was no significant association with AIx ( r =0.18 P =0.11). The strongest independent correlate of AIx was ejection duration, accounting for 78% variance (β=0.88 model R 2 =0.77 P .001). Neither SR (β=0.12 P =0.18) nor heart rate–corrected SR (β=0.02 P =0.72) was associated with AIx. We conclude that AIx is determined by chronotropic rather than inotropic effects, as well as factors other than wave reflection.
Publisher: Springer Science and Business Media LLC
Date: 2015
Publisher: Springer Science and Business Media LLC
Date: 09-11-2020
DOI: 10.1038/S41440-020-00576-Z
Abstract: Reservoir pressure parameters (i.e., reservoir pressure [RP] and excess pressure [XSP]) independently predict cardiovascular events in adults, but this has not been investigated in children. This study aimed to determine (1) the association of reservoir pressure parameters with carotid intima-media thickness (carotid IMT), a preclinical vascular phenotype, and (2) whether a multivariable regression model with or without reservoir pressure parameters fits better for estimating carotid IMT in children. Study participants were 11-12-year-old children (n = 1231, 50% male) from the Child Health CheckPoint study, a cross-sectional substudy of the population-based Longitudinal Study of Australian Children. RP and XSP were obtained using brachial-cuff oscillometry (SphygmoCor XCEL, AtCor, Sydney). Carotid IMT was quantified by vascular ultrasonography. XSP was associated with carotid IMT after adjusting for confounders including age, sex, BMI z-score, heart rate, pubertal stage, moderate-to-vigorous physical activity, and mean arterial pressure (β = 0.93 µm, 95% CI 0.30-1.56 for XSP peak and β = 0.04 µm, 95% CI 0.01-0.08 for XSP integral). The results of the likelihood ratio test indicated a trend that the model with XSP and the above confounders fit better than a similar model without XSP for estimating carotid IMT. Our findings indicate that brachial-cuff device-measured XSP is associated with carotid IMT independent of conventional cardiovascular risk factors, including standard BP. This implies that a clinically convenient cuff approach could provide meaningful information for the early assessment of cardiovascular risk among children.
Publisher: Springer Science and Business Media LLC
Date: 13-03-2014
DOI: 10.1038/JHH.2014.15
Abstract: High-altitude hypoxia causes major cardiovascular changes, which may result in raised resting brachial blood pressure (BP). However, the effect of high-altitude hypoxia on more sensitive measures of BP control (such as 24 h ambulatory BP and resting central BP) is largely unknown. This study aimed to assess this and compare high-altitude responses to resting brachial BP, as well as determine the haemodynamic correlates of acute mountain sickness (AMS) during a progressive trekking ascent to high-altitude. Measures of oxygen saturation (pulse oximetry), 24 h ambulatory BP, resting brachial and central BP (Pulsecor) were recorded in 10 adults (aged 27±4, 30% male) during a 9-day trek to Mount Everest base c , Nepal. Data were recorded at sea level (stage 1 <450 m above sea level (ASL)) and at progressive ascension to 3440 m ASL (stage 2), 4350 m ASL (stage 3) and 5164 m ASL (stage 4). The Lake Louise score (LLS) was used to quantify AMS symptoms. Total LLS increased stepwise from sea level to stage 4 (0.3±0.7 vs 4.4±2.0, P=0.012), whereas oxygen saturation decreased to 77±9% (P=0.001). The highest recordings of 24 h ambulatory, daytime, night time, brachial and central systolic BP and diastolic BP were achieved at stage 3, which were significantly greater than at sea level (P<0.005 for all). Twenty-four-hour ambulatory heart rate (HR) and night HR correlated with oxygen saturation (r=-0.741 and -0.608, both P<0.001) and total LLS (r=0.648 and r=0.493, both P<0.001). We conclude that 24 h ambulatory BP, central BP and HR are elevated during high-altitude hypoxia, but AMS symptoms are only related to tachycardia.
Publisher: S. Karger AG
Date: 2022
DOI: 10.1159/000528208
Abstract: Arterial stiffness is a progressive aging process that predicts cardiovascular disease. Pulse wave velocity (PWV) has emerged as a noninvasive, valid, and reliable measure of arterial stiffness and an independent risk predictor for adverse outcomes. However, up to now, PWV measurement has mostly been used as a tool for risk prediction and has not been widely used in clinical practice. This consensus paper aims to discuss multiple PWV measurements currently available in Asia and to provide evidence-based assessment together with recommendations on the clinical use of PWV. For the methodology, PWV measurement including the central elastic artery is essential and measurements including both the central elastic and peripheral muscular arteries, such as brachial-ankle PWV and cardio-ankle vascular index, can be a good alternative. As Asian populations are rapidly aging, timely detection and intervention of “early vascular aging” in terms of abnormally high PWV values are recommended. More evidence is needed to determine if a PWV-guided therapeutic approach will be beneficial to the prevention of cardiovascular diseases beyond current strategies. Large-scale randomized controlled intervention studies are needed to guide clinicians.
Publisher: Springer International Publishing
Date: 2020
Publisher: Springer Science and Business Media LLC
Date: 2018
Publisher: Informa UK Limited
Date: 30-03-2011
DOI: 10.3109/08037051.2011.566251
Abstract: Masked hypertension (MH) independently predicts mortality but cannot be diagnosed from clinic blood pressure (BP) taken under resting conditions. We sought to determine if MH could be identified from BP taken during a single bout of low-intensity exercise. BP was recorded at rest and during brief low-level cycling exercise (60-70% of age-predicted maximal heart rate) in 75 untreated subjects with a hypertensive response to exercise (aged 54 ± 9 years). All subjects underwent 24-h ambulatory BP monitoring (ABPM) and MH was defined as clinic BP < 140/90 mmHg and ABPM BP ≥ 130/80 mmHg. There were 42 (56%) patients with MH, and at rest systolic (SBP) was higher in subjects with MH compared with those without MH (127 ± 9 vs 120 ± 9 mmHg p < 0.05). During exercise, MH subjects had significantly higher SBP (188 ± 22 vs 168 ± 15 mmHg p < 0.05), with a greater change from baseline (61 ± 21 vs 48 ± 15 mmHg p < 0.05). Low-level exercise SBP was independently associated with MH, and if ≥ 175 mmHg, identified MH with 74% sensitivity and 67% specificity (p < 0.001). MH can be identified in untreated in iduals from low-intensity exercise SBP. Further research on the diagnostic value of BP during early phases of exercise stress testing is needed.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 11-2019
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 07-2011
Publisher: Elsevier BV
Date: 12-2015
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 04-2017
Publisher: Springer Science and Business Media LLC
Date: 2017
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 02-2023
DOI: 10.1161/HYPERTENSIONAHA.122.19693
Abstract: Accurate blood pressure (BP) measurement is critical for optimal cardiovascular risk management. Age-related trajectories for cuff-measured BP accelerate faster in women compared with men, but whether cuff BP represents the intraarterial (invasive) aortic BP is unknown. This study aimed to determine the sex differences between cuff BP, invasive aortic BP, and the difference between the 2 measurements. Upper-arm cuff BP and invasive aortic BP were measured during coronary angiography in 1615 subjects from the Invasive Blood Pressure Consortium Database. This analysis comprised 22 different cuff BP devices from 28 studies. Subjects were 64±11 years (range 40–89) and 32% women. For the same cuff systolic BP (SBP), invasive aortic SBP was 4.4 mm Hg higher in women compared with men. Cuff and invasive aortic SBP were higher in women compared with men, but the sex difference was more pronounced from invasive aortic SBP, was the lowest in younger ages, and the highest in older ages. Cuff diastolic blood pressure overestimated invasive diastolic blood pressure in both sexes. For cuff and invasive diastolic blood pressure separately, there were sex*age interactions in which diastolic blood pressure was higher in younger men and lower in older men, compared with women. Cuff pulse pressure underestimated invasive aortic pulse pressure in excess of 10 mm Hg for both sexes in older age. For the same cuff SBP, invasive aortic SBP was higher in women compared with men. How this translates to cardiovascular risk prediction needs to be determined, but women may be at higher BP-related risk than estimated by cuff measurements.
Publisher: Springer Science and Business Media LLC
Date: 2012
Publisher: Pan American Health Organization
Date: 10-05-2022
Publisher: Oxford University Press (OUP)
Date: 16-08-2019
DOI: 10.1093/AJH/HPZ136
Abstract: Arterial reservoir-wave analysis (RWA)—a new model of arterial hemodynamics—separates arterial wave into reservoir pressure (RP) and excess pressure (XSP). The XSP integral (XSPI) has been associated with increased risk of clinical outcomes. The objectives of the present study were to examine the determinants of XSPI in a mixed cohort of hemodialysis (HD) and peritoneal dialysis (PD) patients, to examine whether dialysis modality and the presence of an arteriovenous fistula (AVF) are associated with increased XSPI. In a cross-sectional study, 290 subjects (232 HD and 130 with AVF) underwent carotid artery tonometry (calibrated with brachial diastolic and mean blood pressure). The XSPI was calculated through RWA using pressure-only algorithms. Logistic regression was used for determinants of XSPI above median. Through forward conditional linear regression, we examined whether treatment by HD or the presence of AVF is associated with higher XSPI. Patients with XSPI above median were older, had a higher prevalence of diabetes and cardiovascular disease, had a higher body mass index, and were more likely to be on HD. After adjustment for confounders, HD was associated with a higher risk of higher XSPI (odds ratio = 2.39, 95% confidence interval: 1.16–4.98). In a forward conditional linear regression analysis, HD was associated with higher XSPI (standardized coefficient: 0.126, P = 0.012), but on incorporation of AVF into the model, AVF was associated with higher XSPI (standardized coefficient: 0.130, P = 0.008) and HD was excluded as a predictor. This study suggests that higher XSPI in HD patients is related to the presence of AVF.
Publisher: Springer Science and Business Media LLC
Date: 04-09-2015
DOI: 10.1007/S00592-015-0802-4
Abstract: People with type 2 diabetes mellitus (T2DM) have abnormal peripheral and central haemodynamics at rest and during exercise, probably due to metabolic perturbations, but mechanisms are unknown. We used untargeted metabolomics to determine the relationships between metabolic perturbations and haemodynamics (peripheral and central) measured at rest and during exercise. Serum s les from 39 participants with T2DM (62 ± 9 years 46 % male) and 39 controls (52 ± 10 years 51 % male) were analysed by liquid chromatography-mass spectrometry, nuclear magnetic resonance spectroscopy and principal component analysis. Scores on principal components (PC) were used to assess relationships with haemodynamics including peripheral and central BP, central augmentation index (AIx) and central augmentation pressure (AP). Participants with T2DM had higher resting and exercise haemodynamics (peripheral and central BP, central AIx and central AP) compared to controls (p < 0.05). PC that comprised of a signature metabolic pattern of T2DM was independently associated with resting and exercise central AIx and central AP (p < 0.05). Serum metabolic profile was associated with central, but not peripheral, haemodynamics in T2DM participants, suggesting that metabolic irregularities may explain abnormal central haemodynamics in T2DM patients.
Publisher: American Physiological Society
Date: 07-2011
DOI: 10.1152/AJPHEART.00102.2011
Abstract: Acute elevation of circulating lipids, such as the postprandial state, contributes to increased cardiovascular risk. However, the effect of acutely elevated triglycerides on arterial and left ventricular function is not completely understood. We aimed to assess whether an acute increase in triglycerides affects ventricular-vascular interaction. Fifteen healthy men (age, 49 ± 8 yr) underwent blinded, randomized infusion of saline and intravenous fat emulsion to acutely raise plasma triglycerides. All subjects underwent both randomization trials, in random order on two separate days. Ventricular-vascular interaction measures were recorded by tonometry (central blood pressure) and echocardiography (left ventricular volumes, strain, and strain rate) at baseline and after 1 h infusion. Net ventricular-vascular interaction was defined by the effective arterial elastance ( E A )-to-left ventricular end-systolic elastance ( E LV ) ratio ( E A / E LV ). When compared with saline, the infusion of intravenous fat emulsion increased triglycerides and free fatty acids (Δ P 0.001 for both) and improved left ventricular contractility (Δ E LV , end-systolic volume and strain rate P 0.05 for all). However, arterial function was unchanged (Δ E A , brachial and central blood pressure P 0.05 for all). Overall, E A / E LV was decreased by an infusion of intravenous fat emulsion ( P = 0.004) but not saline ( P 0.05, P = 0.001 for Δ between trials). We conclude that intravenous fat emulsion and acute elevation of blood lipids (including triglycerides and free fatty acids) alter ventricular-vascular interaction by increasing left ventricular contractility without affecting arterial load. These findings may have implications for cardiovascular responses to parenteral nutrition.
Publisher: Oxford University Press (OUP)
Date: 25-03-2015
DOI: 10.1093/AJH/HPU238
Publisher: S. Karger AG
Date: 2013
DOI: 10.1159/000360975
Abstract: Irrespective of apparent ‘normal' resting blood pressure (BP), some in iduals may experience an excessive elevation in BP with exercise (i.e. systolic BP ≥210 mm Hg in men or ≥190 mm Hg in women or diastolic BP ≥110 mm Hg in men or women), a condition termed exercise hypertension or a ‘hypertensive response to exercise' (HRE). An HRE is a relatively common condition that is identified during standard exercise stress testing however, due to a lack of information with respect to the clinical ramifications of an HRE, little value is usually placed on such a finding. In this review, we discuss both the clinical importance and underlying physiological contributors of exercise hypertension. Indeed, an HRE is associated with an increased propensity for target organ damage and also predicts the future development of hypertension, cardiovascular events and mortality, independent of resting BP. Moreover, recent work has highlighted that some of the elevated cardiovascular risks associated with an HRE may be related to high-normal resting BP (pre-hypertension) or ambulatory ‘masked' hypertension and that an HRE may be an early warning signal of abnormal BP control that is otherwise undetected with clinic BP. Whilst an HRE may be amenable to treatment via pharmacological and lifestyle interventions, the exact physiological mechanism of an HRE remains elusive, but it is likely a manifestation of multiple factors including large artery stiffness, increased peripheral resistance, neural circulatory control and metabolic irregularity. Future research focus may be directed towards determining threshold values to denote the increased risk associated with an HRE and further resolution of the underlying physiological factors involved in the pathogenesis of an HRE.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 06-2020
DOI: 10.1161/HYPERTENSIONAHA.120.14778
Abstract: In iduals with type 2 diabetes mellitus (T2DM) have a greater blood pressure (BP) response to acute maximal exercise compared to those without T2DM however, whether they exhibit a different arterial stiffness response to maximal exercise has yet to be explored. Adults with (n=66) and without T2DM (n=61) underwent an arterial stress test: at rest and immediately postexercise, carotid-femoral pulse wave velocity, the gold standard measure of arterial stiffness, brachial BP, heart rate, and other hemodynamic measurements were assessed. Linear regression models were used to evaluate between-group differences at rest, and the response to exercise (postexercise value), adjusting for covariates including BP and heart rate when relevant, and the corresponding baseline value of each parameter. All participants (mean±SD: age 59.3±10.6 years body mass index 31.2±3.9 kg/m 2 ) had hypertension (mean BP 130±14/80±9 mm Hg). At rest, participants with T2DM had significantly higher carotid-femoral pulse wave velocity (10.3±2.7 versus 9.1±1.9 m/s), heart rate (69±11 versus 66±10 beats/min), and lower diastolic BP (79±9 versus 83±9 mm Hg), but systolic BP (129±15 versus 131±13 mm Hg) was similar. In response to exercise, participants with T2DM showed greater increases in carotid-femoral pulse wave velocity (1.6 [95% CI, 0.4–2.9 m/s]) and systolic BP (9 [95% CI, 1–17 mm Hg]) than participants without T2DM. A greater proportion of participants with T2DM had a hypertensive response to exercise compared to participants without T2DM (n=23, 35% versus n=11, 18% P =0.033). By incorporating exercise as a vascular stressor, we provide evidence of a greater increase in arterial stiffness in in iduals with T2DM, independently of resting arterial stiffness, and the BP postexercise.
Publisher: Elsevier BV
Date: 08-2004
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 11-2013
Publisher: AMPCo
Date: 06-2005
Publisher: Springer Science and Business Media LLC
Date: 10-01-2019
DOI: 10.1038/S41371-018-0154-Y
Abstract: Aortic stiffness predicts cardiovascular mortality but is limited as a risk marker because it is dependent on blood pressure (BP). A potential solution is provided from the ratio of aortic-to-brachial artery stiffness (ab-ratio), which has been shown to be a BP-independent risk marker among patients with renal dysfunction (RD). We sought to determine the BP independence of the ab-ratio in patients with disease, including RD, and healthy populations. The ab-ratio (aortic/brachial pulse wave velocity) and mean arterial pressure (MAP) were recorded in patients with RD (n = 119, aged 65 ± 7 years), hypertension (n = 140, aged 62 ± 9 years), type 2 diabetes mellitus (n = 77, aged 60 ± 9 years) and healthy subjects (n = 99, aged 51 ± 8 years). Multiple-regression analysis was performed to test the independent association of MAP with the ab-ratio adjusted for age, sex, body mass index, glucose and heart rate. There was no significant relationship between the ab-ratio and MAP in patients with RD (β = 0.08, p = 0.34), hypertension (β = 0.04, p = 0.62) or diabetes (β = 0.22, p = 0.11). However, among healthy subjects the ab-ratio was significantly and independently associated with MAP (β = 0.31, p = 0.003). There was a significant difference in the strength of association between the ab-ratio and MAP between patients with disease and healthy subjects (z > 2.2, p < 0.05 all). Although ab-ratio is purported to be a risk marker that is independent of BP, this was observed only among patient populations, and not among healthy subjects. As a result, the ab-ratio has limited potential as a screening tool for the clinical assessment of arterial stiffness in otherwise healthy in iduals.
Publisher: SAGE Publications
Date: 03-06-2023
DOI: 10.1177/09564624231179497
Abstract: In Uganda, it is recommended that persons with HIV receive integrated care to address both hypertension and diabetes. However, the extent to which appropriate diabetes care is delivered remains unknown and was the aim of this study. We conducted a retrospective study among participants receiving integrated care for HIV and hypertension for at least 1 year at a large urban HIV clinic in Mulago, Uganda to determine the diabetes care cascade. Of the 1115 participants, the majority were female ( n = 697, 62.5%) with a median age of 50 years (Inter Quartile Range: 43, 56). Six hundred twenty-seven participants (56%) were screened for diabetes mellitus, 100 (16%) were diagnosed and almost all that were diagnosed ( n = 94, 94%) were initiated on treatment. Eighty-five patients (90%) were retained and all were monitored (100%) in care. Thirty-two patients (32/85, 38%) had glycaemic control. Patients on a Dolutegravir-based regimen (OR = 0.31, 95% CI = 0.22-0.46, p 0.001) and those with a non-suppressed viral load (OR = 0.24, 95% CI = 0.07-0.83, p = 0.02) were less likely to be screened for diabetes mellitus. In very successful HIV care programs, large gaps still linger for the management of non-communicable diseases necessitating uniquely designed intervention by local authorities and implementing partners addressing the dual HIV and non-communicable diseases burden.
Publisher: BMJ
Date: 14-04-2010
DOI: 10.1136/BMJ.C1104
Publisher: Elsevier BV
Date: 03-2011
DOI: 10.1016/J.JCF.2010.12.001
Abstract: Adult patients with cystic fibrosis (CF) have resting abnormal large artery haemodynamics. Here, we obtain further insight in patients with CF by evaluating haemodynamic response to physiological stress. Thirty-six stable CF patients mean (SD) age 28.9 (9.0)years and 25 controls matched for age, gender and body mass index were studied. Central haemodynamic parameters including augmentation index (AIx) and wasted left ventricular pressure energy (∆E(W)) were determined pre, during and post light intensity cycle ergometry. During exercise, despite a similar heart rate and blood pressure, patients had comparatively greater ∆E(W) (P=0.03) and trend towards greater AIx (P=0.07) than controls. Exercise ∆E(W) was greatest in patients with CF related diabetes (n=11). In all subjects, exercise ∆E(W) was related to age (r=0.54, P<0.001) and FEV(1)% predicted (r=-0.32, P=0.01). Adults with CF have an abnormal haemodynamic response to exercise. This finding has deleterious implications for myocardial performance.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 04-2014
Publisher: Oxford University Press (OUP)
Date: 12-09-2013
DOI: 10.1093/AJH/HPT161
Abstract: Physical fitness is known to influence arterial stiffness. Resting heart rate is reduced by exercise and positively associated with arterial stiffness. This study aimed to investigate the role of resting heart rate in the relationship of physical fitness with arterial stiffness. Subjects were 2,328 young adults from the Childhood Determinants of Adult Health study. Cardiorespiratory fitness was estimated as physical work capacity at a heart rate of 170 bpm. Muscular strength was estimated by hand-grip (both sides), shoulder (pull and push), and leg strength. Arterial stiffness was measured using carotid ultrasound. Arterial stiffness was negatively associated with cardiorespiratory fitness (men P < 0.001 women P = 0.002), and positively associated with muscular strength in women (P = 0.002) but not in men. Resting heart rate was positively associated with arterial stiffness (P < 0.001 both men and women). Adjustment for resting heart rate reduced the inverse association of arterial stiffness with cardiorespiratory fitness by 93.7% (men) and 67.6% (women) but substantially increased the positive association of arterial stiffness with muscular strength among women and revealed a positive association of arterial stiffness with muscular strength among men. These findings were independent of body size, blood pressure, biochemical markers, socioeconomic status, smoking, and alcohol consumption. Our findings attribute a key intermediary role for resting heart rate in the relationship between fitness and arterial stiffness, whereby higher cardiorespiratory fitness may reduce arterial stiffness mainly through resting heart rate, and higher muscular strength might have deleterious effects on arterial stiffness that are partially offset by lower resting heart rate.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 09-2012
Publisher: Oxford University Press (OUP)
Date: 29-01-2013
DOI: 10.1093/AJH/HPS077
Abstract: The J-curve relationship between brachial diastolic blood pressure (DBP) and mortality is believed to be mediated through reduced myocardial perfusion. This study aimed to determine the relationship between DBP and subendocardial perfusion in patients with and without coronary artery disease (CAD) and to examine central hemodynamic variables that may explain the risk associated with low DBP (aortic stiffness, central pulse pressure, and augmentation index). Brachial DBP and radial tonometry were measured in 134 patients with CAD (aged 76±7years 69% male), 134 in iduals without a prior cardiovascular event (control subjects) (aged 77±2years 69% male) and 47 patients (aged 63±10years) during dobutamine stress echocardiography. Central hemodynamics and subendocardial viability ratio (SEVR), a marker of subendocardial perfusion, were recorded by tonometry. There was no difference in DBP or SEVR between control subjects and CAD patients (P > 0.05), nor was there a difference in SEVR across quartiles of DBP in CAD patients (P = 0.07) or control subjects (P = 0.14). After adjustment for age and height, associations between DBP and SEVR in control subjects (r = 0.185 P = 0.03) and CAD patients (r = 0.204 P = 0.02) were attenuated (P = 0.07 and P = 0.11, respectively). There were no significant relationships between DBP and central hemodynamics (P > 0.05 for all). At peak dobutamine stress, SEVR was significantly reduced in patients with inducible ischemia vs. those with nonischemic response (84±17 vs. 101±22% P = 0.01). However, DBP was not significantly different (65±14 vs. 67±15mm Hg P = 0.32). Brachial DBP is a poor marker of subendocardial perfusion. The J-curve relationship between DBP and mortality is unlikely attributable to reduced myocardial perfusion or adverse central hemodynamics.
Publisher: AMPCo
Date: 23-02-2021
DOI: 10.5694/MJA2.50960
Publisher: Pan American Health Organization
Date: 17-10-2022
Abstract: La Iniciativa Mundial HEARTS. es la iniciativa emblemática de la Organización Mundial de la Salud para reducir la carga de las enfermedades cardiovasculares, la principal causa de muerte y discapacidad en todo el mundo. La Iniciativa HEARTS en las Américas es la adaptación regional que propone usar HEARTS como modelo para el manejo del riesgo de enfermedades cardiovasculares, incluida la hipertensión, y la diabetes en la atención primaria de salud en la Región de las Américas para el año 2025. Esta iniciativa está iniciando su sexto año de aplicación y ya incluye a 22 países y 1 380 centros de atención primaria de salud. Este informe tiene tres objetivos. En primer lugar, describir cómo surgió la Iniciativa HEARTS en las Américas y cuáles son sus principales elementos. En segundo lugar, resumir las principales innovaciones logradas para catalizar la iniciativa y mantener su aplicación. Entre estas innovaciones se encuentran: a) la introducción de factores impulsores del control de la hipertensión b) el desarrollo de una vía clínica integral y práctica c) la elaboración de una estrategia para mejorar la precisión de la medición de la presión arterial d) la creación de un marco de seguimiento y evaluación y e) la elaboración de un conjunto estandarizado de recursos de capacitación y formación. En tercer lugar, en este informe se examinan las futuras prioridades de la iniciativa. El objetivo de poner en marcha estas soluciones innovadoras y pragmáticas es crear un sistema de salud más efectivo y trasladar el enfoque de los programas cardiovasculares y de hipertensión del nivel de atención altamente especializada a la atención primaria de salud. Además, HEARTS en las Américas puede servir como modelo para unas prácticas más integrales, efectivas y sostenibles en la prevención y el tratamiento de las enfermedades no transmisibles.
Publisher: Elsevier BV
Date: 09-2012
DOI: 10.1194/JLR.P027706
Publisher: Annals of Family Medicine
Date: 2016
DOI: 10.1370/AFM.1883
Publisher: Springer Science and Business Media LLC
Date: 19-02-2015
DOI: 10.1038/HR.2015.9
Abstract: Although physical activity (PA) improves arterial distensibility, it is unclear which type of activity is most beneficial. We aimed to examine the association of different types of PA with carotid distensibility (CD) and the mechanisms involved. Data included 4503 Australians and Finns aged 26-45 years. Physical activity was measured by pedometers and was self-reported. CD was measured using ultrasound. Other measurements included resting heart rate (RHR), cardiorespiratory fitness (CRF), blood pressure, biomarkers and anthropometry. Steps/day were correlated with RHR (Australian men r = -0.10, women r = - 0.14 Finnish men r = -0.15, women r = -0.11 P<0.01), CRF and biochemical markers, but not with CD. Self-reported vigorous leisure-time activity was more strongly correlated with RHR (Australian men r = -0.23, women r = -0.19 Finnish men r = -0.20, women r = -0.13 P < 0.001) and CRF, and was correlated with CD (Australian men r = 0.07 Finnish men r = 0.07, women r = 0.08 P < 0.05). This relationship of vigorous leisure-time activity with CD was mediated by RHR independently of potential confounders. In summary, vigorous leisure-time PA but not total or less intensive PA was associated with arterial distensibility in young to mid-aged adults. Promotion of vigorous PA is therefore recommended among this population. RHR was a key intermediary factor explaining the relationship between vigorous PA and arterial distensibility.
Publisher: Elsevier BV
Date: 07-2008
DOI: 10.1016/J.JSAMS.2006.11.005
Abstract: Central hemodynamics such as ascending aortic blood pressure (BP), wave reflection and myocardial perfusion are clinically important in the context of cardiovascular health. Ultra-endurance athletes may be at greater risk of cardiovascular abnormalities due to chronically increased physiological stress placed on the cardiovascular system. This study was a cross-sectional investigation that compared central hemodynamics in ultra-endurance athletes and matched controls. Forty-four athletes (36 males aged mean+/-S.D., 34+/-8 years) undergoing ultra-endurance training (16.3+/-3.7 h/week) were compared to 44 matched recreationally active (1.2+/-0.9 h/week) controls (36 males aged 34+/-8 years). Brachial BP was measured using an oscillometric device while central hemodynamics including ascending aortic BP, wave reflection (augmentation index, AIx), ejection duration, sub-endocardial perfusion (SEVR) and timing of the reflected wave (T(R)) were determined by applanation tonometry and pulse wave analysis. There were no significant (P>0.05) differences between groups in AIx (athletes and controls 6+/-12% versus 6+/-13%, respectively), T(R) (athletes and controls 165+/-22 ms versus 165+/-19 ms, respectively), brachial (athletes and controls 51+/-9 mmHg versus 48+/-12 mmHg, respectively) or central pulse pressure (33+/-5 mmHg versus 31+/-7 mmHg). However, athletes had significantly increased SEVR (226+/-42% versus 198+/-46% P<0.001) despite having a longer ejection duration (348+/-19 ms versus 339+/-18 ms P 0.05). Ultra-endurance athletes had increased sub-endocardial perfusion capacity and the quantity of exercise training was associated with central rather than peripheral hemodynamics.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 12-06-2023
Publisher: Springer Science and Business Media LLC
Date: 18-06-2009
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 08-2016
Publisher: Wiley
Date: 16-03-2007
DOI: 10.1111/J.1365-2362.2007.01784.X
Abstract: The first derivative of left ventricular (LV) pressure over time (dP/dt max) is a marker of LV systolic function that can be assessed during cardiac catheterization and echocardiography. Radial artery dP/dt max has been proposed as a possible marker of LV systolic function and we sought to test this hypothesis. We compared simultaneously recorded radial dP/dt max (by high-fidelity tonometry) with LV dP/dt max (by high-fidelity catheter and echocardiography parameters analogous to LV dP/dt max). In study 1, beat-to-beat radial dP/dt max and LV dP/dt max were recorded at rest and during supine exercise in 12 males (aged 61 +/- 12 years) undergoing cardiac catheterization. In study 2, 2D-echocardiography and radial dP/dt max were recorded in 54 patients (separate to study 1 39 men aged 64 +/- 10 years) at baseline and peak dobutamine-induced stress. Three basal septum measures were taken as being analogous to LV dP/dt max: 1. Peak systolic strain rate 2. Strain rate (SR-dP/dt max) during isovolumic contraction (IVCT) and 3. Tissue velocity during IVCT. In study 1 there was a significant difference between resting LV dP/dt max (1461 +/- 383 mmHg s(-1)) and radial dP/dt max (1182 +/- 319 mmHg s(-1) P < 0.001), and a poor, but statistically significant, correlation between the variables (R(2) = 0.006 P < 0.05). Similar results were observed during exercise. In study 2 there were weak (R(2) = -0.12 P = 0.01) to non-significant associations between radial dP/dt max and all echocardiographic measures analogous to LV dP/dt max at rest or peak stress. Radial pressure waveform dP/dt max is not a reliable marker of LV systolic function.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 2019
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 05-2019
DOI: 10.1161/HYPERTENSIONAHA.119.12674
Abstract: Radial intra-arterial blood pressure (BP) is sometimes used as the reference standard for validation of brachial cuff BP devices. Moreover, there is an emerging wearables market seeking to measure BP at the wrist. However, radial systolic BP may differ when compared with brachial yet some authors have labeled these differences as a fictional Popeye phenomenon. Indeed, differences between brachial and radial systolic BP have never been accurately quantified, and this was the aim of this study. Intra-arterial BP was measured consecutively at the brachial and radial artery in 180 participants undergoing coronary angiography (aged 61±10 years 69% men). On average, radial systolic BP was 5.5 mm Hg higher than brachial systolic BP. Only 43% of participants had radial systolic BP within ±5 mm Hg of brachial. Additionally, 46%, 19%, and 13% of participants had radial systolic BP , between 5 and 10, and between 10 and 15 mm Hg higher than brachial respectively. A further 14% of participants had radial systolic BP mm Hg higher than brachial, representing the so-called Popeye phenomenon. Finally, 11% of participants had radial systolic BP mm Hg lower than brachial. In conclusion, radial systolic BP is not representative of brachial systolic BP, with most participants having a radial systolic BP mm Hg higher than brachial and many with differences mm Hg. Therefore, validation testing of BP devices utilizing intra-arterial BP as the reference standard should use intra-arterial BP measured at the same site as the brachial cuff or wearable device.
Publisher: Wiley
Date: 19-11-2018
DOI: 10.1111/JCH.13411
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 07-2005
DOI: 10.1161/01.HYP.0000165310.84801.E0
Abstract: Isolated systolic hypertension is a common condition in in iduals aged older than 60 years. However, isolated systolic hypertension has also been described in young in iduals, although the mechanisms are poorly understood. We hypothesized that in young adults, isolated systolic hypertension and essential hypertension have different hemodynamic mechanisms and the aim of this study was to test this hypothesis in a cohort of subjects from The ENIGMA Study. Peripheral and central blood pressure, aortic pulse wave velocity, cardiac output, stroke volume, and peripheral vascular resistance were determined in 1008 subjects, aged 17 to 27 years. Compared with normotensive subjects, those with isolated systolic hypertension had significantly higher peripheral, central, and mean blood pressure, aortic pulse wave velocity, cardiac output, and stroke volume ( P .001 for all comparisons). However, there were no differences in pulse pressure lification, heart rate, or peripheral vascular resistance between the two groups. Compared with subjects with essential hypertension, mean pressure, heart rate, and peripheral vascular resistance were all significantly lower in isolated systolic hypertensive subjects, but pulse pressure lification, aortic pulse wave velocity, cardiac output, and stroke volume were higher ( P .001 for all comparisons). We have demonstrated that in young adults, isolated systolic hypertension and essential hypertension arise from different hemodynamic mechanisms. Isolated systolic hypertension appears to result from an increased stroke volume and/or aortic stiffness, whereas the major hemodynamic abnormality underlying essential hypertension is an increased peripheral vascular resistance. Long-term follow-up of these in iduals is now required to determine whether they are at increased risk compared with age-matched normotensive in iduals.
Publisher: Elsevier BV
Date: 08-2023
Publisher: Springer Science and Business Media LLC
Date: 13-12-2012
DOI: 10.1038/HR.2012.198
Abstract: We examined changes in central blood pressure (BP) following resistance exercise training (RET) in men and women with prehypertension and never-treated hypertension. Both Windkessel theory and wave theory were used to provide a comprehensive examination of hemodynamic modulation with RET. Twenty-one participants (age 61±1 years, n=6 male average systolic blood pressure (SBP)/diastolic blood pressure (DBP)=138/84 mm Hg) were randomized to either 12 weeks of RET (n=11) or an inactive control group. Central BP and augmentation index (AIx) were derived from radial pressure waveforms using tonometry and a generalized transfer function. A novel reservoir-wave separation technique was used to derive excess wave pressure (related to forward and backward traveling waves) and reservoir pressure (related to the capacitance/Windkessel properties of the arterial tree). Wave separation using traditional impedance analysis and aortic flow triangulation was also applied to derive forward wave pressure (Pf) and backward wave pressure (Pb). There was a group-by-time interaction (P<0.05) for central BP as there was a significant ~6 mm Hg reduction in SBP and ~7 mm Hg reduction in DBP following RET with no change in the control condition. There were also group-by-time interactions (P 0.05). RET may reduce central BP in older adults with hypertension and prehypertension by lowering Pf and reservoir pressure without affecting pressure from wave reflections.
Publisher: Elsevier BV
Date: 12-2016
DOI: 10.1016/J.JSAMS.2016.04.004
Abstract: Exaggerated exercise blood pressure (EEBP) recorded during exercise testing at moderate-intensity is independently associated with cardiovascular mortality. It is hypothesized that EEBP may be indicative of underlying hypertension unnoticed by standard clinic (resting) BP measures (thus explaining increased mortality risk), but this has never been confirmed by association with hypertension defined using ambulatory BP monitoring, which was the aim of this study. Cross-sectional study. 100 consecutive patients free from coronary artery disease (aged 56±9 years, 72% male) underwent clinically indicated exercise stress testing. Exercise BP was recorded at each stage of the Bruce protocol. Presence of hypertension was defined as 24-hour systolic BP ≥130mmHg or daytime systolic BP ≥135mmHg. Exercise systolic BP at stage 1 and 2 of the test was significantly associated with the presence of hypertension (P 130mmHg (AUC=0.752, 95% CI's 0.649-0.846, P 150mmHg predicting hypertension independently of age, sex and in-clinic hypertension status (OR=4.83, 95% CI's 1.62-14.39, P=0.005). Irrespective of resting BP, systolic BP ≥150mmHg during early stages of the Bruce exercise stress test is associated with presence of hypertension. EEBP should be a warning signal to health/exercise professionals on the presence of hypertension and the need to provide follow up care to reduce cardiovascular risk.
Publisher: Wiley
Date: 08-05-2021
DOI: 10.1111/SMS.13976
Abstract: Exaggerated exercise blood pressure (BP) is associated with cardiovascular risk factors in adolescence. Cardiorespiratory fitness and adiposity (fatness) are independent contributors to cardiovascular risk, but their interrelated associations with exercise BP are unknown. This study aimed to determine the relationships between fitness, fatness, and the acute BP response to exercise in a large birth cohort of adolescents. 2292 adolescents from the Avon Longitudinal Study of Parents and Children (aged 17.8 ± 0.4 years, 38.5% male) completed a sub‐maximal exercise step test that allowed fitness (VO 2 max ) to be determined from workload and heart rate using a validated equation. Exercise BP was measured immediately on test cessation and fatness calculated as the ratio of total fat mass to total body mass measured by DXA. Post‐exercise systolic BP decreased stepwise with tertile of fitness (146 (18) 142 (17) 141 (16) mmHg) but increased with tertile of fatness (138 (15) 142 (16) 149 (18) mmHg). In separate models, fitness and fatness were associated with post‐exercise systolic BP adjusted for sex, age, height, smoking, and socioeconomic status (standardized β: −1.80, 95%CI: −2.64, −0.95 mmHg/SD and 4.31, 95%CI: 3.49, 5.13 mmHg/SD). However, when fitness and fatness were included in the same model, only fatness remained associated with exercise BP (4.65, 95%CI: 3.69, 5.61 mmHg/SD). Both fitness and fatness are associated with the acute BP response to exercise in adolescence. The fitness‐exercise BP association was not independent of fatness, implying the cardiovascular protective effects of cardiorespiratory fitness may only be realized with more favorable body composition.
Publisher: Oxford University Press (OUP)
Date: 04-2012
DOI: 10.1038/AJH.2011.238
Abstract: Noninvasive central blood pressure (BP) independently predicts mortality, but current methods are operator-dependent, requiring skill to obtain quality recordings. The aims of this study were first, to determine the validity of an automatic, upper arm oscillometric cuff method for estimating central BP (O(CBP)) by comparison with the noninvasive reference standard of radial tonometry (T(CBP)). Second, we determined the intratest and intertest reliability of O(CBP). To assess validity, central BP was estimated by O(CBP) (Pulsecor R6.5B monitor) and compared with T(CBP) (SphygmoCor) in 47 participants free from cardiovascular disease (aged 57 ± 9 years) in supine, seated, and standing positions. Brachial mean arterial pressure (MAP) and diastolic BP (DBP) from the O(CBP) device were used to calibrate in both devices. Duplicate measures were recorded in each position on the same day to assess intratest reliability, and participants returned within 10 ± 7 days for repeat measurements to assess intertest reliability. There was a strong intraclass correlation (ICC = 0.987, P < 0.001) and small mean difference (1.2 ± 2.2 mm Hg) for central systolic BP (SBP) determined by O(CBP) compared with T(CBP). Ninety-six percent of all comparisons (n = 495 acceptable recordings) were within 5 mm Hg. With respect to reliability, there were strong correlations but higher limits of agreement for the intratest (ICC = 0.975, P < 0.001, mean difference 0.6 ± 4.5 mm Hg) and intertest (ICC = 0.895, P < 0.001, mean difference 4.3 ± 8.0 mm Hg) comparisons. Estimation of central SBP using cuff oscillometry is comparable to radial tonometry and has good reproducibility. As a noninvasive, relatively operator-independent method, O(CBP) may be as useful as T(CBP) for estimating central BP in clinical practice.
Publisher: Elsevier BV
Date: 08-2017
DOI: 10.1016/J.JACC.2017.05.064
Abstract: Hypertension (HTN) is the single greatest cardiovascular risk factor worldwide. HTN management is usually guided by brachial cuff blood pressure (BP), but questions have been raised regarding accuracy. This comprehensive analysis determined the accuracy of cuff BP and the consequent effect on BP classification compared with intra-arterial BP reference standards. Three in idual participant data meta-analyses were conducted among studies (from the 1950s to 2016) that measured intra-arterial aortic BP, intra-arterial brachial BP, and cuff BP. A total of 74 studies with 3,073 participants were included. Intra-arterial brachial systolic blood pressure (SBP) was higher than aortic values (8.0 mm Hg 95% confidence interval [CI]: 5.9 to 10.1 mm Hg p < 0.0001) and intra-arterial brachial diastolic BP was lower than aortic values (-1.0 mm Hg 95% CI: -2.0 to -0.1 mm Hg p = 0.038). Cuff BP underestimated intra-arterial brachial SBP (-5.7 mm Hg 95% CI: -8.0 to -3.5 mm Hg p < 0.0001) but overestimated intra-arterial diastolic BP (5.5 mm Hg 95% CI: 3.5 to 7.5 mm Hg p < 0.0001). Cuff and intra-arterial aortic SBP showed a small mean difference (0.3 mm Hg 95% CI: -1.5 to 2.1 mm Hg p = 0.77) but poor agreement (mean absolute difference 8.0 mm Hg 95% CI: 7.1 to 8.9 mm Hg). Concordance between BP classification using the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure cuff BP (normal, pre-HTN, and HTN stages 1 and 2) compared with intra-arterial brachial BP was 60%, 50%, 53%, and 80%, and using intra-arterial aortic BP was 79%, 57%, 52%, and 76%, respectively. Using revised intra-arterial thresholds based on cuff BP percentile rank, concordance between BP classification using cuff BP compared with intra-arterial brachial BP was 71%, 66%, 52%, and 76%, and using intra-arterial aortic BP was 74%, 61%, 56%, and 65%, respectively. Cuff BP has variable accuracy for measuring either brachial or aortic intra-arterial BP, and this adversely influences correct BP classification. These findings indicate that stronger accuracy standards for BP devices may improve cardiovascular risk management.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 09-04-2020
Abstract: Two in iduals can have a similar pulse pressure ( PP ) but different levels of systolic blood pressure ( SBP ), although the underlying mechanisms have not been described. We hypothesized that, for a given level of PP , differences in SBP relate to peripheral vascular resistance ( PVR ) and we tested this hypothesis in a large cohort of healthy young adults. Demographic, biochemical, and hemodynamic data from 3103 subjects were available for the current analyses. In both men and women, for a given level of PP , higher SBP was associated with significantly higher body weight, body mass index, heart rate, and PVR ( P .05 versus those with lower BP for all comparisons). Moreover, stratifying in iduals by quartiles of PP and PVR revealed a stepwise increase in SBP from the lowest to highest quartile for each variable, with the highest SBP occurring in those in the highest quartile of both PP and PVR ( P .001 for overall trend for both sexes). PVR was also increased with increasing tertile of minimum forearm vascular resistance, in both men ( P =0.002) and women ( P =0.03). Increased PVR , mediated in part through altered resistance vessel structure, strongly associates with the elevation of SBP for a given level of PP in young adults. An impaired ability to adapt PVR appropriately to a given level of PP may be an important mechanism underlying elevated SBP in young adults.
Publisher: Springer Science and Business Media LLC
Date: 11-10-2008
Publisher: Wiley
Date: 07-2018
Publisher: American Physiological Society
Date: 08-2010
DOI: 10.1152/JAPPLPHYSIOL.00196.2010
Abstract: In the present study, we examined the influence of preload augmentation via passive leg elevation (PLE) on synthesized aortic blood pressure, aortic augmentation index (AIx), and aortic capacitance (a reflection of aortic reservoir function). Central and peripheral hemodynamics were measured via tonometry with a generalized transfer function in 14 young, healthy men (age = 24 yr). Aortic blood flow was calculated from the left ventricular outflow tract (LVOT) velocity-time integral (VTI) using standard two-dimensional echocardiographic-Doppler techniques. Measures were made in the supine position at rest (Pre), during PLE, and during recovery (Post). There was a significant increase in LVOT-VTI, synthesized aortic systolic blood pressure (BP) and AIx from Pre to PLE, with values returning to baseline Post ( P 0.05). There was a reduction in aortic capacitance from Pre to PLE, with values returning to baseline Post ( P 0.05). There was no change in heart rate, systemic arterial compliance, aortic elastance, aortic wave travel timing, or vascular resistance ( P 0.05). Change in AIx from Pre to PLE was associated with change in LVOT-VTI ( r = 0.66, P 0.05) and inversely associated with change in aortic capacitance ( r = −0.73, P 0.05). These data suggest that in a setting of isolated augmented preload with minimal changes in other potential confounders, the morphology of the synthesized aortic BP waveform and AIx may be related to changes in aortic reservoir function.
Publisher: Oxford University Press (OUP)
Date: 07-07-2015
DOI: 10.1093/AJH/HPV108
Abstract: Central blood pressure (BP) is an acknowledged contributor to end-organ damage and independent determinant of prognosis. Primary analysis from the BPGUIDE study demonstrated no detriment on left ventricular (LV) structure from central BP-guided hypertension management, despite significant medication withdrawal. However, the effect of this on LV function has not been investigated. In this study, we sought to investigate the impact of central BP-guided hypertension management on LV systolic and diastolic performance. A total of 286 enrollees with uncomplicated hypertension were randomized to therapeutic decisions guided by best-practice usual care (UC) or, in addition, by central BP intervention (CBP) for 12 months. Each participant underwent baseline and follow-up 2-dimensional echocardiography, with assessment undertaken by an expert blinded to participant allocation. Antihypertensive medication quantity remained unchanged for UC but significantly decreased with intervention. However, no significant between-group differences were noted for changes during follow-up in both brachial and central BP, as well as other central hemodynamic parameters: augmentation index and augmented pressure. Similarly, there were no differences between groups in parameters of LV diastolic function: tissue e' velocity (∆UC vs. ∆CBP P = 0.27) and E/e' ratio (∆UC vs. ∆CBP P = 0.60), and systolic parameters: LV longitudinal strain (∆UC vs. ∆CBP P = 0.55), circumferential strain (∆UC vs. ∆CBP P = 0.79), and ejection fraction (∆UC vs. ∆CBP P = 0.15). Hypertension management guided by central BP, resulting in significant withdrawal of medication to maintain appropriate BP control, had no adverse effect on LV systolic or diastolic function. Clinical trials registration: Australia New Zealand Clinical Trial Registry Number ACTRN12608 000041358.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 05-2011
Publisher: S. Karger AG
Date: 2020
DOI: 10.1159/000506646
Abstract: b i Background: /i /b Blood collection and blood pressure (BP) measurements are routinely performed during the same consultation to assess absolute cardiovascular disease (CVD) risk. This study aimed to determine the effect of blood collection on BP and subsequent calculation of the absolute CVD risk. b i Methods: /i /b Forty-five participants aged 58 ± 9 years (53% male) had systolic BP (SBP) measured using clinical guideline methods (clinic SBP). Then, on a separate visit, BP was measured immediately before, during, and after blood collection. Absolute CVD risk scores were calculated (Framingham equation) using SBP from each measurement condition and compared. b i Results: /i /b The prevalence of low (& #x3c %), moderate (10–15%), and high (≥15%) absolute CVD risks among the participants was 67%, 22%, and 11%, respectively, using clinic SBP. SBP values before and during blood collection were significantly higher compared to values after blood collection (130 ± 18 and 132 ± 19 vs. 126 ± 18 mm Hg i /i = 0.010 and i /i = 0.003, respectively). However, there were no significant differences between clinic SBP (128 ± 18 mm Hg) and blood collection SBP ( i /i = 0.99) or the absolute CVD risk scores (7.3 ± 6.5 7.6 ± 5.9 7.7 ± 6.1 and 7.1 ± 5.7%, respectively i /i = 0.995 for all). The mean intraclass correlation (95% CI) indicated good agreement between absolute CVD risk scores calculated with clinic SBP and each blood collection SBP (0.86 [95% CI 0.74–0.92], 0.85 [95% CI 0.71–0.91], and 0.87 [95% CI 0.76–0.93], respectively i /i & #x3c 0.001, for all). b i Conclusion: /i /b Absolute CVD risk calculation is not affected by use of SBP measurements recorded at the time of blood collection. Therefore, it is acceptable to collect blood and measure BP during the same consultation for absolute CVD risk assessment.
Publisher: Research Square Platform LLC
Date: 03-02-2023
DOI: 10.21203/RS.3.RS-2366159/V1
Abstract: Introduction: The VALID BP project was initiated to increase the availability of validated blood pressure measuring devices (BPMDs). The goal is to eliminate non validated BPMDs and minimise over- and underdiagnosis of hypertension caused by inaccurate readings. This study was undertaken to assess the potential return on investment in the VALID BP project. Methods: The Framework to Assess the Impact of Translational health research was applied to the VALID BP project. One of the three methods used included a cost benefit analysis to monetise past research investment and model future research costs, implementation costs and benefits. Analysis was based on reasoned assumptions about potential impacts from availability and use of validated BPMDs (assuming an end goal of 100% validated BPMDs available in Australia by 2028) and improved skills leading to more accurate BP measurement. Results: After five years, with 20% attribution of benefits, there is a potential $1.29 return for every dollar spent if the proportion of validated BPMDs and staff trained in proper BP measurement technique increased from 20–60%. After eight years (2020–2028) and assuming universal validation and training coverage, the returns would be $3.20 per dollar spent (not including cost of side-effects of unnecessary medication or downstream patient impacts from unmanaged hypertension). Conclusion: This modelled economic analysis indicates there will be positive downstream economic benefits if the availability of validated BPMDs is increased. The findings support ongoing efforts toward a universal regulatory framework for BPMDs and can be considered within more detailed future economic analyses.
Publisher: Wiley
Date: 05-10-2020
DOI: 10.1111/JCH.14065
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 06-2020
Publisher: Elsevier BV
Date: 2017
Publisher: Springer Science and Business Media LLC
Date: 18-10-2017
DOI: 10.1007/S11906-017-0787-1
Abstract: This review aimed to provide a clinical update on exercise blood pressure (BP) and its relationship to cardiovascular disease (CVD), outlining key determinants of abnormal exercise BP responses. We also highlight current evidence gaps that need addressing in order to optimise the relevance of exercise BP as clinical CVD risk factor. Abnormal exercise BP manifests as either exercise hypotension (low BP response) or as exaggerated exercise BP (high BP response). Exercise hypotension is an established sign of existing and likely severe CVD, but exaggerated exercise BP also carries elevated CVD risk due to its association with sub-clinical hypertension. Although exaggerated exercise BP is related to heightened CVD risk at any exercise intensity, recent data suggest that the BP response to submaximal intensity exercise holds greater prognostic and clinical significance than BP achieved at peak/maximal intensity exercise. Cardiorespiratory fitness is a strong modifier of the exercise BP response, and should be taken into consideration when assessing the association with CVD. Both exercise hypotension and exaggerated exercise BP serve as markers that should prompt evaluation for potential underlying CVD. However, the clinical utility of these markers is currently inhibited by the lack of consensus informing the definitions and thresholds for abnormalities in exercise BP.
Publisher: Oxford University Press (OUP)
Date: 30-05-2017
DOI: 10.1093/AJH/HPX091
Abstract: Aortic reservoir function independently predicts end-organ damage in cross-sectional analyses. However, longitudinal associations are more important regarding causation, but this has never been examined at rest or in response to light-moderate intensity exercise. The aim of this study was to determine the association between the change in aortic reservoir characteristics, in particular excess pressure integral (Pexcess) at rest and in response to exercise and the change in kidney function among healthy in iduals followed over time. Aortic reservoir function (Pexcess and reservoir pressure), aortic stiffness, brachial and central blood pressure (BP), and renal function (estimated glomerular filtration rate [eGFR]) were recorded among 33 healthy in iduals (57 ± 9 years 55% male) at baseline and after an average 3.0 ± 0.3 years. Over the follow up period, there was a significant increase in resting brachial BP, central BP, Pexcess, and aortic stiffness (P & 0.05 all). The change over time in resting Pexcess (but not aortic stiffness) was significantly related to the change in eGFR (r = −0.38, P = 0.038) and remained independent of age at follow up, change in 24-hour ambulatory systolic BP and body mass index (β = −0.0300, P = 0.043). There was no association between the change in aortic pulse wave velocity and the change eGFR (P = 0.46) nor were there any associations with exercising hemodynamics. Pexcess is independently associated with a decline in renal function among healthy people followed over 3 years. These novel findings indicate the need to determine the underlying physiological determinants of aortic reservoir function.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 10-2022
DOI: 10.1161/HYPERTENSIONAHA.122.19420
Abstract: Exaggerated exercise blood pressure (EEBP) during clinical exercise testing is associated with poor blood pressure (BP) control and cardiovascular disease (CVD). Type-2 diabetes (T2DM) is thought to be associated with increased prevalence of EEBP, but this has never been definitively determined and was the aim of this study. Clinical exercise test records were analyzed from 13 268 people (aged 53±13 years, 59% male) who completed the Bruce treadmill protocol (stages 1–4, and peak) at 4 Australian public hospitals. Records (including BP) were linked to administrative health datasets (hospital and emergency admissions) to define clinical characteristics and classify T2DM (n=1199) versus no T2DM (n=12 069). EEBP was defined as systolic BP ≥90th percentile at each test stage. Exercise BP was regressed on T2DM history and adjusted for CVD and risk factors. Prevalence of EEBP (age, sex, preexercise BP, hypertension history, CVD history and aerobic capacity adjusted) was 12% to 51% greater in T2DM versus no T2DM (prevalence ratio [95% CI], stage 1, 1.12 [1.02–1.24] stage 2, 1.51 [1.41–1.61] stage 3, 1.25 [1.10–1.42] peak, 1.18 [1.09–1.29]). At stages 1 to 3, 8.6% to 15.8% (4.8%–9.7% T2DM versus 3.5% to 6.1% no-T2DM) of people with ‘normal’ preexercise BP ( /90 mm Hg) were identified with EEBP. Exercise systolic BP relative to aerobic capacity (stages 1–4 and peak) was higher in T2DM with adjustment for all CVD risk factors. People with T2DM have higher prevalence of EEBP and exercise systolic BP independent of CVD and many of its known risk factors. Clinicians supervising exercise testing should be alerted to increased likelihood of EEBP and thus poor BP control warranting follow-up care in people with T2DM.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 06-05-2021
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 23-08-2022
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 11-2018
Publisher: CRC Press
Date: 06-06-2019
Publisher: Springer Science and Business Media LLC
Date: 21-10-2021
DOI: 10.1007/S10554-021-02444-4
Abstract: Afterload is an important determinant of left ventricular (LV) and atrial (LA) function, including myocardial strain. Central blood pressure (CBP) is the major component of cardiac afterload and independently associated with cardiovascular risk. However, the optimal means of calibrating CBP is unclear-standard CBP assessment uses systolic (SBP) and diastolic blood pressure (DBP) from brachial waveforms, but calibration with mean pressure (MAP) and DBP purports to be more accurate. Therefore, we sought to determine which CBP is best associated with LA and LV strain. CBP was measured using both standard and MAP based calibration methods in 546 participants (age 70.7 ± 4.7 years, 45% male) with risk factors for heart failure. Echocardiography was performed in all patients and strain analysis conducted to assess LA/LV function. The associations of CBP with LA and LV strain were assessed using linear regression. MAP-derived CSBP (150 ± 20 mmHg) was higher than standard CSBP (128 ± 15 mmHg) and brachial SBP (140 ± 17 mmHg, p 0.05), however was independently associated with LA reservoir strain (p 0.05). MAP-derived CBP was more accurate in identifying patients with abnormal LA and LV strain than brachial SBP and standard CBP calibration. In conclusion, CBP calibrated using MAP and DBP may be more accurate in identifying patients with abnormal LA and LV function than standard brachial calibration methods.
Publisher: Oxford University Press (OUP)
Date: 07-2016
DOI: 10.1093/EHJCI/JEW135
Abstract: Load dependence is an important source of variation in left ventricular (LV) deformation. This impacts on the precision of information obtained from serial measurements. However, it is clinically important to distinguish actual myocardial dysfunction from changes associated with altered loading conditions. We sought to investigate the association of changes of loading parameters with changes in LV longitudinal (GLS) and circumferential (GCS) strains. Baseline and a 12-month follow-up 2D echocardiograms were performed in 191 Stage A heart failure patients with uncomplicated hypertension. These patients underwent simultaneous measurement of conventional and central blood pressures (BPs) and haemodynamic measurements by applanation tonometry. Significant, but weak correlations (r = 0.15-0.28) of LV strain parameters and their changes over the follow-up period were shown for the majority of LV afterload-associated variables, including central and brachial systolic, diastolic, and mean BPs 24-h systolic and diastolic BPs peak reservoir and excess pressures central augmented pressure (CAP) and pulse pressure augmentation index and arterial elastance index (EaI). Central mean BP, EaI, and changes in CAP and EaI over follow-up were independent contributors to LV deformation in multivariable analysis. No improvement in the Bland-Altman 95% limits of agreement and correlation coefficients was seen with LV afterload correction of GLS and GCS using central BP indices. LV longitudinal and circumferential strains in a population without apparent heart disease is relatively insusceptible to changes in LV afterload within physiological range, which, therefore, seem unlikely to be a significant confounder in repeated GLS or GCS observations.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 04-2018
Publisher: Springer Science and Business Media LLC
Date: 07-12-2022
Publisher: Oxford University Press (OUP)
Date: 27-05-2019
Publisher: American Diabetes Association
Date: 07-07-2017
DOI: 10.2337/DC16-2750
Abstract: Insulin increases glucose disposal in part by enhancing microvascular blood flow (MBF) and substrate delivery to myocytes. Insulin’s microvascular action is impaired with insulin resistance and type 2 diabetes. Resistance training (RT) improves glycemic control and insulin sensitivity, but whether this improvement is linked to augmented skeletal muscle microvascular responses in type 2 diabetes is unknown. Seventeen (11 male and 6 female 52 ± 2 years old) sedentary patients with type 2 diabetes underwent 6 weeks of whole-body RT. Before and after RT, participants who fasted overnight had clinical chemistries measured (lipids, glucose, HbA1c, insulin, and advanced glycation end products) and underwent an oral glucose challenge (OGC) (50 g × 2 h). Forearm muscle MBF was assessed by contrast-enhanced ultrasound, skin MBF by laser Doppler flowmetry, and brachial artery flow by Doppler ultrasound at baseline and 60 min post-OGC. A whole-body DEXA scan before and after RT assessed body composition. After RT, muscle MBF response to the OGC increased, while skin microvascular responses were unchanged. These microvascular adaptations were accompanied by improved glycemic control (fasting blood glucose, HbA1c, and glucose area under the curve [AUC] during OGC) and increased lean body mass and reductions in fasting plasma triglyceride, total cholesterol, advanced glycation end products, and total body fat. Changes in muscle MBF response after RT significantly correlated with reductions in fasting blood glucose, HbA1c, and OGC AUC with adjustment for age, sex, % body fat, and % lean mass. RT improves OGC-stimulated muscle MBF and glycemic control concomitantly, suggesting that MBF plays a role in improved glycemic control from RT.
Publisher: Elsevier
Date: 2022
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 09-2015
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 05-2020
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 08-2019
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 16-06-2022
Publisher: Wiley
Date: 27-01-2021
DOI: 10.1111/JCH.14193
Abstract: A clinical audit of hospitals in Thailand was conducted to assess compliance with the national hypertension treatment guidelines and determine hypertension control rates across facilities of different sizes. Stratified random s ling was used to select sixteen hospitals of different sizes from four provinces. These included community ( beds), large (90–120 beds), and provincial ( beds) hospitals. Among new cases, the audit determined whether (i) the recommended baseline laboratory assessment was completed, (ii) the initial choice of medication was appropriate based on the patient's cardiovascular risk, and (iii) patients received medication adjustments when indicated. The hypertension control rates at six months and at the last visit were recorded. Among the 1406 patients, about 75% had their baseline glucose and kidney function assessed. Nearly 30% ( n = 425/1406) of patients were indicated for dual therapy but only 43% of them ( n = 182/425) received this. During treatment, 28% (198/1406) required adjustments in medication but this was not done. The control of hypertension at six months after treatment initiation was 53% varying between 51% in community and 56% in large hospitals ( p .01). The hypertension control rate at last visit was 64% but varied between 59% in community hospitals and 71% in large hospitals ( p .01). Failure to adjust medication when required was associated with 30% decrease in the odds of hypertension control (OR 0.69, 95% CI 0. 50 to 0.90). Failure to comply with the treatment guidelines regarding adjustment of medication and lost to follow‐up are possible target areas to improve hypertension control in Thailand.
Publisher: Elsevier BV
Date: 09-2008
Location: United States of America
Start Date: 2009
End Date: 2012
Funder: National Health and Medical Research Council
View Funded ActivityStart Date: 2005
End Date: 2006
Funder: University of Queensland
View Funded ActivityStart Date: 2011
End Date: 2012
Funder: University of Tasmania
View Funded ActivityStart Date: 2008
End Date: 2008
Funder: National Health and Medical Research Council
View Funded ActivityStart Date: 2011
End Date: 2013
Funder: National Heart Foundation of Australia
View Funded ActivityStart Date: 2010
End Date: 2011
Funder: Diabetes Australia Research Trust
View Funded ActivityStart Date: 2016
End Date: 2017
Funder: National Heart Foundation of Australia
View Funded ActivityStart Date: 2014
End Date: 2018
Funder: National Health and Medical Research Council
View Funded Activity