ORCID Profile
0000-0003-3375-5568
Current Organisation
University of Adelaide
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Publisher: Authorea, Inc.
Date: 27-09-2023
Publisher: BMJ
Date: 04-2019
DOI: 10.1136/HEARTJNL-2018-314471
Abstract: The aim of this study is to characterise hospitalisations due to atrial fibrillation (AF) compared with two other common cardiovascular conditions, myocardial infarction (MI) and heart failure (HF), in addition to the associated economic burden of these hospitalisations and contribution of AF-related procedures. The primary outcome measure was the rate of increase of AF, MI and HF hospitalisations from 1993 to 2013. The rate of increase of AF-related procedures including cardioversion and ablation were also collected, in addition to direct costs associated with hospitalisations for each of these three conditions. AF hospitalisations increased 295% over the 21-year period to a total of 61 424 in 2013. In comparison, MI and HF hospitalisations increased by only 73% and 39%, respectively, over the same period. Considering population changes, there was an annual increase in AF hospitalisations of 5.2% (incidence rate ratio [IRR] 1.052 95% CI 1.046 to 1.059 p .001). In contrast, there was a 2.2% increase per annum for MI (IRR 1.022 95% CI 1.017 to 1.027 p .001) and negligible annual change for HF hospitalisations (IRR 1.000 95% CI 0.997 to 1.002 p=0.78). Cardioversion and AF ablation increased by 10% and 26% annually, respectively. AF hospitalisation costs rose by 479% over the 21-year period, an increase that was more than double that of MI and HF. The burden of AF hospitalisations continues to rise unabated. AF has now surpassed both MI and HF hospitalisations and represents a growing cost burden. New models of healthcare delivery are required to stem this growing healthcare burden.
Publisher: Elsevier BV
Date: 04-2018
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 02-2014
DOI: 10.1161/CIRCEP.113.000882
Abstract: Surviving myocytes within scar may form channels that support ventricular tachycardia (VT) circuits. There are little data on the properties of channels that comprise VT circuits and those that are non-VT supporting channels. In 22 patients with ischemic cardiomyopathy and VT, high-density mapping was performed with the PentaRay catheter and Ensite NavX system during sinus rhythm. A channel was defined as a series of matching pace-maps with a stimulus (S) to QRS time of ≥40 ms. Sites were determined to be part of a VT channel if there were matching pace-maps to the VT morphology. This was confirmed with entrainment mapping when possible. Of the 238 channels identified, 57 channels corresponded to an inducible VT. Channels that were part of a VT circuit were more commonly located within dense scar than non-VT channels (97% versus 82% P =0.036). VT supporting channels were of greater length (mean±SEM, 53±5 versus 33±4 mm), had higher longest S-QRS (130±12 versus 82±12 ms), longer conduction time (103±14 versus 43±13 ms), and slower conduction velocity (0.87±0.23 versus 1.39±0.21 m/s) than non-VT channels ( P .001). Of all the fractionated, late, and very late potentials located in scar, only 21%, 26%, and 29%, respectively, were recorded within VT channels. High-density mapping shows substantial differences among channels in ventricular scar. Channels supporting VT are more commonly located in dense scar, longer than non-VT channels, and have slower conduction velocity. Only a minority of scar-related potentials participate in the VT supporting channels.
Publisher: Wiley
Date: 02-02-2022
DOI: 10.1111/JCE.15387
Abstract: Although single ring isolation is an accepted strategy for undertaking pulmonary vein (PV) and posterior wall isolation (PWI) during atrial fibrillation (AF) ablation, the learning curve associated with this technique as well as procedural and clinical success rates have not been widely reported. Prospectively collected data from 250 consecutive patients undergoing de novo AF ablation using single ring isolation. PWI was achieved in 212 patients (84.8%) and PV isolation without PWI was achieved in 37 patients (14.4%). Thirty-one cases (12.4%) demonstrated inferior line sparing where PWI was achieved without a continuous posterior wall inferior line. A learning curve was observed, with higher rates of PWI (98% last 50 vs. 82% first 50 cases, p = .016), higher rates of inferior line sparing (20% last 50 vs. 8% first 50 cases, p = .071) and lower ablation times (43.8 min (interquartile range [IQR]: 34.6-57.0 min) last 50 versus. 96.5 min (IQR: 80.8-115.8 min) first 50 cases p < .001). Three (1.3%) major procedure-related complications were observed. Twelve-month, single-procedure freedom from atrial arrhythmia without drugs was 70.5% (95% confidence interval [CI]: 61.5%-77.7%) and 60.0% (95% CI: 50.2%-68.4%) for paroxysmal and persistent/longstanding persistent AF. Twelve-month multi-procedure freedom from atrial arrhythmia was 92.2% (95%CI: 85.6%-95.9%) and 85.6% (95%CI: 77.2%-91.0%) for paroxysmal and persistent/longstanding persistent AF. Employing a single ring isolation approach, PWI can be achieved in most cases. There is a substantial learning curve with higher rates of PWI, reduced ablation times, and higher rates of inferior line sparing as procedural experience grows. Long-term freedom from arrhythmia is comparable to other AF ablation techniques.
Publisher: Elsevier BV
Date: 06-2015
DOI: 10.1016/J.JACEP.2015.04.004
Abstract: The purpose of this study was to quantify the magnitude of association between incremental increases in body mass index (BMI) and the development of incident, post-operative, and post-ablation atrial fibrillation (AF). Obesity has been estimated to account for one-fifth of all AF and approximately 60% of recent increases in population AF incidence. From a public health perspective, obesity, therefore, is a modifiable risk factor that could be profitably targeted. A systematic review and meta-analysis was conducted. Medline and EMBASE databases were searched for observational studies reporting data on the association between obesity and incident, post-operative, and post-ablation AF. Studies were included if they reported or provided data allowing calculation of risk estimates. Data from 51 studies including 626,603 in iduals contributed to this analysis. There were 29% (odds ratio [OR]: 1.29, 95% confidence interval [CI]: 1.23 to 1.36) and 19% (OR: 1.19, 95% CI: 1.13 to 1.26) greater excess risks of incident AF for every 5-U BMI increase in cohort and case-control studies, respectively. Similarly, there were 10% (OR: 1.10, 95% CI: 1.04 to 1.17) and 13% (OR: 1.13, 95% CI: 1.06 to 1.22) greater excess risks of post-operative and post-ablation AF for every 5-U increase in BMI, respectively. Incremental increases in BMI are associated with a significant excess risk of AF in different clinical settings. For every 5-U increase in BMI, there were 10% to 29% greater excess risks of incident, post-operative, and post-ablation AF. By providing a comprehensive and reliable quantification of the relationship between incremental increases in obesity and AF across different clinical settings, our findings highlight the potential for even moderate reductions in population body mass indexes to have a significant effect in mitigating the rising burden of AF.
Publisher: Elsevier BV
Date: 03-2016
Publisher: Elsevier BV
Date: 09-2017
DOI: 10.1016/J.HLC.2017.05.123
Abstract: Atrial fibrillation (AF) is a leading cause of cardiovascular morbidity and mortality worldwide. Management of AF is a complex process involving: 1) the prevention of thromboembolic complications with anticoagulation 2) rhythm control and 3) the detection and treatment of underlying heart disease. However, cardiometabolic risk factors, such as obesity, hypertension, diabetes mellitus, and obstructive sleep apnoea, have been proposed as contributors to the expanding epidemic of atrial fibrillation (AF). Thus, a fourth pillar of AF care would include aggressive targeting of interdependent, modifiable cardiovascular risk factors as part of an integrated care model. Such risk factor management could retard and reverse the pathological processes underlying AF and reduce AF burden.
Publisher: Elsevier
Date: 2017
Publisher: Wiley
Date: 06-2018
DOI: 10.1002/CLC.22967
Publisher: Elsevier BV
Date: 03-2021
Publisher: Oxford University Press (OUP)
Date: 14-06-2018
Abstract: Atrial fibrillation (AF) is a progressive disease. Obesity is associated with progression of AF. This study evaluates the impact of weight and risk factor management (RFM) on progression of the AF. As described in the Long-Term Effect of Goal-Directed Weight Management in an Atrial Fibrillation Cohort: A Long-Term Follow-Up (LEGACY) Study, of 1415 consecutive AF patients, 825 had body mass index ≥ 27 kg/m2 and were offered weight and RFM. After exclusion, 355 were included for analysis. Weight loss was categorized as: Group 1 (<3%), Group 2 (3-9%), and Group 3 (≥10%). Change in AF type was determined by clinical review and 7-day Holter yearly. Atrial fibrillation type was categorized as per the Heart Rhythm Society consensus. There were no differences in baseline characteristic or follow-up duration between groups (P = NS). In Group 1, 41% progressed from paroxysmal to persistent and 26% from persistent to paroxysmal or no AF. In Group 2, 32% progressed from paroxysmal to persistent and 49% reversed from persistent to paroxysmal or no AF. In Group 3, 3% progressed to persistent and 88% reversed from persistent to paroxysmal or no AF (P < 0.001). Increased weight loss was significantly associated with greater AF freedom: 45 (39%) in Group 1, 69 (67%) in Group 2, and 116 (86%) in Group 3 (P ≤ 0.001). Obesity is associated with progression of the AF disease. This study demonstrates the dynamic relationship between weight/risk factors and AF. Weight-loss management and RFM reverses the type and natural progression of AF.
Publisher: Springer Science and Business Media LLC
Date: 27-05-2010
DOI: 10.1007/S00246-010-9731-8
Abstract: This report describes a 1(1/2)-year-old boy who succumbed to acute obstruction of the left ventricular outflow tract by a cardiac rhabdomyoma. He was admitted to have a transient loss of consciousness episode evaluated. A mobile intracardiac mass obstructing the left ventricular outflow tract and protruding into the aortic root during systole was detected by transthoracic echocardiography. At autopsy, it was confirmed to be a rhabdomyoma.
Publisher: Elsevier BV
Date: 06-2015
DOI: 10.1016/J.JACC.2015.04.029
Abstract: Remote monitoring (RM) of implantable cardioverter-defibrillators (ICD) is an established technology integrated into clinical practice. One recent randomized controlled trial (RCT) and several large device database studies have demonstrated a powerful survival advantage for ICD patients undergoing RM compared with those receiving conventional in-office (IO) follow-up. This study sought to conduct a systematic published data review and meta-analysis of RCTs comparing RM with IO follow-up. Electronic databases and reference lists were searched for RCTs reporting clinical outcomes in ICD patients who did or did not undergo RM. Data were extracted from 9 RCTs, including 6,469 patients, 3,496 of whom were randomized to RM and 2,973 to IO follow-up. In the RCT setting, RM demonstrated clinical outcomes comparable with office follow-up in terms of all-cause mortality (odds ratio [OR]: 0.83 p = 0.285), cardiovascular mortality (OR: 0.66 p = 0.103), and hospitalization (OR: 0.83 p = 0.196). However, a reduction in all-cause mortality was noted in the 3 trials using home monitoring (OR: 0.65 p = 0.021) with daily verification of transmission. Although the odds of receiving any ICD shock were similar in RM and IO patients (OR: 1.05 p = 0.86), the odds of inappropriate shock were reduced in RM patients (OR: 0.55 p = 0.002). Meta-analysis of RCTs demonstrates that RM and IO follow-up showed comparable overall outcomes related to patient safety and survival, with a potential survival benefit in RCTs using daily transmission verification. RM benefits include more rapid clinical event detection and a reduction in inappropriate shocks.
Publisher: Elsevier BV
Date: 05-2015
DOI: 10.1016/J.JACC.2015.03.002
Abstract: Obesity and atrial fibrillation (AF) frequently coexist. Weight loss reduces the burden of AF, but whether this is sustained, has a dose effect, or is influenced by weight fluctuation is unknown. This study sought to evaluate the long-term impact of weight loss and weight fluctuation on rhythm control in obese in iduals with AF. Of 1,415 consecutive patients with AF, 825 had a body mass index ≥ 27 kg/m(2) and were offered weight management. After screening for exclusion criteria, 355 were included in this analysis. Weight loss was categorized as group 1 (≥ 10%), group 2 (3% to 9%), and group 3 (<3%). Weight trend and/or fluctuation was determined by yearly follow-up. We determined the impact on the AF severity scale and 7-day ambulatory monitoring. There were no differences in baseline characteristics or follow-up among the groups. AF burden and symptom severity decreased more in group 1 compared with groups 2 and 3 (p < 0.001 for all). Arrhythmia-free survival with and without rhythm control strategies was greatest in group 1 compared with groups 2 and 3 (p < 0.001 for both). In multivariate analyses, weight loss and weight fluctuation were independent predictors of outcomes (p < 0.001 for both). Weight loss ≥ 10% resulted in a 6-fold (95% confidence interval: 3.4 to 10.3 p 5% partially offset this benefit, with a 2-fold (95% confidence interval: 1.0 to 4.3 p = 0.02) increased risk of arrhythmia recurrence. Long-term sustained weight loss is associated with significant reduction of AF burden and maintenance of sinus rhythm. (Long-Term Effect of Goal directed weight management on Atrial Fibrillation Cohort: A 5 Year follow-up study [LEGACY Study] ACTRN12614001123639).
Publisher: Elsevier BV
Date: 2013
DOI: 10.1016/J.HRTHM.2012.08.043
Abstract: Obesity is associated with atrial fibrillation (AF) however, the mechanisms by which it induces AF are unknown. To examine the effect of progressive weight gain on the substrate for AF. Thirty sheep were studied at baseline, 4 months, and 8 months, following a high-calorie diet. Ten sheep were s led at each time point for cardiac magnetic resonance imaging and hemodynamic studies. High-density multisite biatrial epicardial mapping was used to quantify effective refractory period, conduction velocity, and conduction heterogeneity index at 4 pacing cycle lengths and AF inducibility. Histology was performed for atrial fibrosis, inflammation, and intramyocardial lipidosis, and molecular analysis was performed for endothelin-A and -B receptors, endothelin-1 peptide, platelet-derived growth factor, transforming growth factor β1, and connective tissue growth factor. Increasing weight was associated with increasing left atrial volume (P = .01), fibrosis (P = .02), inflammatory infiltrates (P = .01), and lipidosis (P = .02). While there was no change in the effective refractory period (P = .2), there was a decrease in conduction velocity (P<.001), increase in conduction heterogeneity index (P<.001), and increase in inducible (P = .001) and spontaneous (P = .001) AF. There was an increase in atrial cardiomyocyte endothelin-A and -B receptors (P = .001) and endothelin-1 (P = .03) with an increase in adiposity. In association, there was a significant increase in atrial interstitial and cytoplasmic transforming growth factor β1 (P = .02) and platelet-derived growth factor (P = .02) levels. Obesity is associated with atrial electrostructural remodeling. With progressive obesity, there were changes in atrial size, conduction, histology, and expression of profibrotic mediators. These changes were associated with spontaneous and more persistent AF.
Publisher: Cambridge University Press (CUP)
Date: 18-06-2007
DOI: 10.1017/S104795110700087X
Abstract: A patent vertical vein might be desirable in patients with obstructive totally anomalous pulmonary venous connection with pulmonary hypertension, in order to decrease perioperative pulmonary arterial pressure and avoid pulmonary hypertensive crises. A subset of patients with an unligated vertical vein requires interruption of the vein due to the development of significant left-to-right shunt and right heart failure. We describe here a new device, permitting adjustable ligation of the vertical vein, which permits us to avoid multiple reoperations. In five patients, aged 2, 4, 3, 4, and 3 months respectively, and undergoing rechannelling of totally anomalous pulmonary venous connection with an unligated vertical vein, were treated with a device permitting adjusted ligation of the vertical vein over the course of postoperative congestive cardiac failure. There was no early or late death. Postoperatively, all ligatures were tightened gradually over a period of 24 to 96 hours, maintaining stable haemodynamics. At a mean follow-up of 55.40 months, there was no evidence of congestive heart failure in any patient, the clinical risk score varying from zero to 2, and no requirement of anti-failure medications. Computed tomographic angiograms during follow-up revealed absence of flow through the vertical vein, and ruled out distortion of the left upper pulmonary and left brachiocephalic veins. Use of a percutaneously adjustable device to ligate the vertical vein allows gradual tightening or loosening of the ligature under optimal physiologic conditions, without re-opening the sternum, or having to resort to another thoracotomy once the reactive components of pulmonary hypertension disappear.
Publisher: Elsevier BV
Date: 10-2019
DOI: 10.1016/J.JACEP.2019.08.007
Abstract: Education has long been recognized as an important component of chronic condition management. Whereas education has been evaluated in atrial fibrillation (AF) populations as part of multifaceted interventions, it has never been tested as a single entity. The aim of this review is to describe the rationale for and role of education as part of comprehensive AF management. The development and use of educational material as part of the intervention of a randomized controlled trial, the HELP-AF (Home-Based Education and Learning Program in AF) study, will be described. This study was designed to determine the impact of a home-based structured educational program on outcomes in in iduals with AF. An educational resource was developed to facilitate delivery of 4 key messages targeted at empowering in iduals to self-manage their condition. The key messages focused on strategies for managing future AF episodes, the role of pharmacotherapy in the treatment of AF, the appropriate use of medicines to manage stroke risk and the role of cardiovascular risk factor management in AF. To support structured educational visiting, an educational booklet titled Living Well With Atrial Fibrillation (AF) was developed by a multidisciplinary team and was further refined following input from expert clinicians and patient interviews. Using a structured educational visiting approach, education was delivered by trained clinicians within the patient's home.
Publisher: Elsevier BV
Date: 12-2014
DOI: 10.1016/J.JACC.2014.09.028
Abstract: The long-term outcome of atrial fibrillation (AF) ablation demonstrates attrition. This outcome may be due to failure to attenuate the progressive substrate promoted by cardiovascular risk factors. The goal of this study was to evaluate the impact of risk factor and weight management on AF ablation outcomes. Of 281 consecutive patients undergoing AF ablation, 149 with a body mass index ≥27 kg/m(2) and ≥1 cardiac risk factor were offered risk factor management (RFM) according to American Heart Association/American College of Cardiology guidelines. After AF ablation, all 61 patients who opted for RFM and 88 control subjects were assessed every 3 to 6 months by clinic review and 7-day Holter monitoring. Changes in the Atrial Fibrillation Severity Scale scores were determined. There were no differences in baseline characteristics, number of procedures, or follow-up duration between the groups (p = NS). RFM resulted in greater reductions in weight (p = 0.002) and blood pressure (p = 0.006), and better glycemic control (p = 0.001) and lipid profiles (p = 0.01). At follow-up, AF frequency, duration, symptoms, and symptom severity decreased more in the RFM group compared with the control group (all p < 0.001). Single-procedure drug-unassisted arrhythmia-free survival was greater in RFM patients compared with control subjects (p < 0.001). Multiple-procedure arrhythmia-free survival was markedly better in RFM patients compared with control subjects (p < 0.001), with 16% and 42.4%, respectively, using antiarrhythmic drugs (p = 0.004). On multivariate analysis, type of AF (p < 0.001) and RFM (hazard ratio 4.8 [95% confidence interval: 2.04 to 11.4] p < 0.001) were independent predictors of arrhythmia-free survival. Aggressive RFM improved the long-term success of AF ablation. This study underscores the importance of therapy directed at the primary promoters of the AF substrate to facilitate rhythm control strategies.
Publisher: Wiley
Date: 13-09-2019
DOI: 10.1111/JCE.14168
Publisher: Elsevier BV
Date: 03-2010
Publisher: Wiley
Date: 27-07-2017
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 25-02-2020
Publisher: Elsevier BV
Date: 04-2016
DOI: 10.1016/J.JACEP.2015.12.014
Abstract: This study sought to characterize the clinical characteristics, atrial substrate, and prognosis in a subgroup of patients with persistent atrial fibrillation (AF) from the onset (PsAFonset). Patients with AF frequently progress from trigger-driven paroxysmal arrhythmias to substrate-dependent persistent arrhythmias. Patients referred for persistent AF (PsAF) ablation were enrolled from 3 centers. Consecutive patients with PsAFonset (n = 129) were compared with patients with PsAF that progressed from paroxysmal AF (n = 231). In addition, 90 patients (30 patients with PsAFonset and 60 control subjects) were studied with noninvasive mapping to characterize the AF drivers. The degree of fractionation and endocardial voltages were assessed invasively. Patients with PsAFonset were younger (p = 0.047) and more obese (p < 0.001) there were more men (p = 0.034), more patients with hypertension (p = 0.044), and these patients had larger left (p < 0.05) and right atria (p < 0.05). Baseline AF cycle length was shorter in the PsAFonset group (p < 0.01) the degree of fractionation was higher (p < 0.001 for both atria), and the endocardial voltage was lower (p < 0.05 for both atria). Patients with PsAFonset had higher a number of re-entrant driver regions (p < 0.001) and extrapulmonary vein regions that had re-entrant drivers (p < 0.05), whereas control subjects displayed more focal driver regions (p = 0.029). The acute AF termination rate was lower in the PsAFonset group (42% vs. 81% p < 0.001). During a mean follow-up of 17 ± 11 months from the last procedure, patients with PsAFonset had significantly higher AF, atrial tachycardia (AT), and AF/AT recurrence rates (p < 0.01). Patients with PsAFonset represent a distinct subgroup defined by specific demographics, underlying diffuse biatrial substrate disease, and worse clinical outcome. The findings highlight the importance of defining criteria for early detection of atrial substrate disease.
Publisher: Elsevier BV
Date: 09-2017
DOI: 10.1016/J.HLC.2017.05.119
Abstract: Recent advances in our understanding of the mechanisms underlying atrial fibrillation (AF) have further underscored the complex pathophysiological basis of the arrhythmia. It has become apparent that the current clinical classification of AF does not reflect the severity of the underlying atrial disease. Atrial fibrosis has been identified as the key structural change in different substrates that are responsible for the perpetuation of AF. Three-dimensional electroanatomical mapping and late gadolinium-enhanced magnetic resonance imaging are novel modalities that can be used to facilitate identification and quantitation of atrial fibrosis for improved delineation of the AF substrate. Advances in AF mapping technology using endocardial 'panaromic' basket-type catheter and non-invasive body surface electrodes have facilitated the identification of two major arrhythmic mechanisms of interest, namely rotational ('rotors') and ectopic focal activations ('foci'). Ongoing research on these potential drivers of AF may provide guidance to more mechanistic based therapies to improve outcomes for this complex arrhythmia in the future. Here, we aim to review the differences in AF substrate in those with paroxysmal and more persistent forms of the arrhythmia by evaluating fibrosis, rotors and foci, towards improved AF substrate classification and in idualised substrate based therapies.
Publisher: Elsevier BV
Date: 11-2019
DOI: 10.1016/J.CJCA.2019.07.627
Abstract: Atrial fibrillation (AF) management guidelines recommend screening for symptoms of sleep-disordered breathing (SDB). We aimed to assess the role of self-reported daytime sleepiness in detection of patients with SDB and AF. A total of 442 consecutive ambulatory patients with AF who were considered candidates for rhythm control and underwent polysomnography comprised the study population. The utility of daytime sleepiness (quantified by the Epworth Sleepiness Scale [ESS]) to predict any (apnea-hypopnea index [AHI] ≥ 5), moderate-to-severe (AHI ≥ 15), and severe (AHI ≥ 30) SDB on polysomnography was tested. Mean age was 60 ± 11 years and 69% patients were men. SDB was present in two-thirds of the population with 33% having moderate-to-severe SDB. Daytime sleepiness was low (median ESS = 8/24) and the ESS poorly predicted SDB, regardless of the degree of SDB tested (area under the curve: 0.48-0.56). Excessive daytime sleepiness (ESS ≥ 11) was present in 11.9% of the SDB population and had a negative predictive value of 43.1% and a positive predictive value of 67.5% to detect moderate-to-severe SDB. Male gender (odds ratio [OR]: 2.3, 95% confidence interval [CI]: 1.4-3.8, P = 0.001), obesity (OR: 3.5, 95% CI: 2.3-5.5, P < 0.001), diabetes (OR: 2.3, 95% CI: 1.2-4.4, P = 0.08), and stroke (OR: 4.6, 95% CI: 1.7-12.3, P = 0.002) were independently associated with an increased likelihood of moderate-to-severe SDB. In an ambulatory AF population, SDB was common but most patients reported low daytime sleepiness levels. Clinical features, rather than daytime sleepiness, were predictive of patients with moderate-to-severe SDB. Lack of excessive daytime sleepiness should not preclude patients from being investigated for the potential presence of concomitant SDB.
Publisher: BMJ
Date: 09-05-2012
DOI: 10.1136/HEARTJNL-2012-301799
Abstract: The left atrial appendage (LAA) has been suggested to be the dominant location of thrombus in atrial fibrillation (AF) and has led to the development of LAA occlusion as a therapeutic modality to reduce stroke risk. However, the patient populations that would benefit most from this therapy are not well defined. A systematic review was performed to better define subgroups amenable to appendage closure. The English scientific literature was searched using Pubmed through to March 1, 2011. Reference lists of relevant and review articles were screened to retrieve additional articles. Studies were only included if they described the location of thrombus in left atrium. Case reports and case series describing less than 10 thrombi were excluded. Two reviewers independently extracted data and assessed quality of each study. A total of 34 studies reporting on the location of atrial thrombus in patients with AF were included: 17 in valvular AF, 10 non-valvular AF and 8 in mixed valvular and non-valvular AF. Atrial thrombi were located outside the LAA in 56% (95% CI 53, 60) of valvular AF, 22% (95% CI 19, 25) in mixed cohorts and 11% (95% CI 6, 15) non-valvular AF. In non valvular AF, the studies with higher proportion of thrombi in the left atrial cavity had non-anticoagulated patients and a greater proportion of ventricular dysfunction and history of stroke. The location of atrial thrombus in patients with AF is dependent on the underlying substrate. In valvular AF, more than half the thrombi are located in the left atrial cavity. In the non-valvular AF group, a smaller proportion of thrombi were located outside the appendage. However, in certain subgroups (ie. non anti-coagulated, left ventricular dysfunction or prior stroke) the chances of left atrial cavity thrombus are higher.
Publisher: Elsevier BV
Date: 02-2019
Publisher: Elsevier BV
Date: 03-2013
Publisher: Informa UK Limited
Date: 24-04-2023
Publisher: Oxford University Press (OUP)
Date: 03-2018
Abstract: Several techniques have been utilized for the ablation of persistent (P) and long-standing persistent (LsP) atrial fibrillation (AF) however, the best approach of substrate ablation remains poorly defined. This study aims to examine the impact of ablation approach on outcomes associated with P or LsP AF ablation by conducting a meta-analysis and regression on contemporary literature. A systematic literature review was conducted up to 29 July 2015 for scientific literature reporting on outcomes associated with P or LsP AF ablation. One hundred and thirteen studies reported outcomes in a total of 18 657 patients undergoing various ablation approaches for the treatment of P-LsP AF between 2001 and 2015. The point efficacy estimate of a single-AF ablation procedure without the use of anti-arrhythmic drugs was 43% (95% CI 39-47%). Multiple procedures and/or the use of anti-arrhythmic drugs increase success to 69% (95% CI 66-71%). Meta-regression revealed that ablation technique (P < 0.001) and left atrial size (P = 0.02) were predictive of single procedure, drug-free success. The addition of extra-pulmonary substrate approaches was associated with declining efficacy when compared to a pulmonary vein ablation alone. The efficacy of a single-AF ablation procedure for P or LsP AF is 43% however, can be increased to 69% with the use of multiple procedures and/or anti-arrhythmic drugs. Current literature supports the finding that pulmonary vein antrum ablation/isolation is at least equivalently efficacious to other contemporary P-LsP ablation strategies.
Publisher: Springer Science and Business Media LLC
Date: 15-10-2018
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 12-2012
DOI: 10.1161/CIRCEP.112.974436
Abstract: Magnetic resonance imaging (MRI)–guided interventional electrophysiology (EP) has rapidly emerged as a promising alternative to x-ray–guided ablation. We aimed to evaluate an externally irrigated MRI-compatible ablation catheter and integrated EP pacing and recording system, testing the feasibility of pulmonary vein and cavo-tricuspid isthmus ablation. Externally irrigated MRI-compatible ablation and diagnostic EP catheters and an integrated EP recording system (Imricor Medical Systems, Burnsville, MN) were tested in n=11 sheep in a 1.5-T MRI scanner. Power-controlled (40 W, 120-second duration) lesions were formed at the pulmonary vein and cavo-tricuspid isthmus. Real-time intracardiac electrograms were recorded during MRI. Steady-state free precession non–breath-hold images were repeatedly acquired to guide catheter navigation. Lesion visualization was performed using noncontrast (T2-weighted turbo spin echo pulse sequence) and gadolinium-diethylene triamine pentaacetic acid–enhanced T1-weighted imaging (inversion-recovery gradient echo pulse sequence). Catheters were able to be visualized and navigated under cardiovascular magnetic resonance guidance. In total, 8±2.5 lesions (radiofrequency time, 16±4.2 minutes) were formed at the pulmonary vein ostia, and 6.5±1.3 lesions (radiofrequency time, 13±2.2 minutes) were formed at the cavo-tricuspid isthmus, with the end point of bidirectional block. The mean procedure time was 150±55 minutes. Lesion visualization with both T2W imaging and contrast-enhanced imaging correlated with sites of injury at autopsy. These data demonstrate the feasibility of using multiple catheters, an integrated EP pacing and recording system, and externally irrigated ablation with cardiovascular magnetic resonance guidance to undertake clinically relevant biatrial mapping and ablation.
Publisher: BMJ
Date: 16-10-2020
DOI: 10.1136/HEARTJNL-2020-317418
Abstract: To characterise the rate, causes and predictors of cessation of non-vitamin K antagonist oral anticoagulants (NOACs) in patients with atrial fibrillation (AF). Consecutive patients with AF with a long-term anticoagulation indication treated with NOACs (dabigatran, apixaban and rivaroxaban) in our centre from September 2010 through December 2016 were included. Prospectively collected data with baseline characteristics, causes of cessation, mean duration-to-cessation and predictors of cessation were analysed. The study comprised 1415 consecutive patients with AF, of whom 439 had a CHA 2 DS 2 -VASc≥1 and were on a NOAC. Mean age was 71.9±8.7 years and 37% were females. Over a median follow-up of 3.6 years (IQR=2.7–5.3), 147 (33.5%) patients ceased their index-NOAC (113 switched to a different form of OAC), at a rate of 8.8 per 100 patient-years. Serious adverse events warranting NOAC cessation occurred in 28 patients (6.4%) at a rate of 1.6 events per 100 patient-years. The mean duration-to-cessation was 4.9 years (95% CI 4.6 to 5.1) and apixaban had the longest duration-to-cessation with (5.1, 95% CI 4.8 to 5.4) years, compared with dabigatran (4.6, 95% CI 4.2 to 4.9) and rivaroxaban (4.5, 95% CI 3.9 to 5.1), pairwise log-rank p=0.002 and 0.025, respectively. In multivariable analyses, age was an independent predictor of index-NOAC cessation (HR 1.03, 95% CI 1.01 to 1.05 p=0.006). Female gender (HR 2.2, 95% CI 1.04 to 4.64 p=0.04) independently predicted serious adverse events. In this ‘real world’ cohort, NOAC use is safe and well-tolerated when prescribed in an integrated care clinic. Whether apixaban is better tolerated compared with other NOACs warrants further study.
Publisher: Elsevier BV
Date: 09-2021
Publisher: Wiley
Date: 23-01-2009
Publisher: BMJ
Date: 04-2020
DOI: 10.1136/OPENHRT-2020-001257
Abstract: To undertake a systematic review and meta-analysis examining the impact of polypharmacy on health outcomes in atrial fibrillation (AF). PubMed and Embase databases were searched from inception until 31 July 2019. Studies including post hoc analyses of prospective randomised controlled trials or observational design that examined the impact of polypharmacy on clinically significant outcomes in AF including mortality, hospitalisations, stroke, bleeding, falls and quality of life were eligible for inclusion. A total of six studies were identified from the systematic review, with three studies reporting on common outcomes and used for a meta-analysis. The total study population from the three studies was 33 602 and 37.2% were female. Moderate and severe polypharmacy, defined as 5–9 medicines and medicines, was observed in 42.7% and 20.7% of patients respectively, and was associated with a significant increase in all-cause mortality (Hazard ratio [HR] 1.36, 95% CI 1.20 to 1.54, p .001 HR 1.84, 95% CI 1.40 to 2.41, p .001, respectively), major bleeding (HR 1.32, 95% CI 1.14 to 1.52, p .001 HR 1.68, 95% CI 1.35 to 2.09, p .001, respectively) and clinically relevant non-major bleeding (HR 1.12, 95% CI 1.03 to 1.22, p .01 HR 1.48, 95% CI 1.33 to 1.64, p .01, respectively). There was no statistically significant association between polypharmacy and stroke or systemic embolism or intracranial bleeding. Among other examined outcomes, polypharmacy was associated with cardiovascular death, hospitalisation, reduced quality of life and poorer physical function. Polypharmacy is highly prevalent in the AF population and is associated with numerous adverse outcomes. CRD42018105298.
Publisher: Elsevier BV
Date: 11-2016
DOI: 10.1016/J.IJCARD.2016.08.113
Abstract: Insertable cardiac monitors (ICMs) are increasingly utilized for diagnosis of unexplained syncope and arrhythmia monitoring. The Reveal LINQ is a novel miniaturized ICM with improved algorithms. The feasibility and safety of insertion outside the traditional electrophysiology laboratory is unknown. Here we compare outcomes of Reveal LINQ insertion in different environments. We report on a prospective, single-centre, non-randomized, observational experience of consecutive Reveal LINQ implantation in the electrophysiology laboratory or a procedure room between October 2013 and October 2015. Of 178 consecutive patients who underwent LINQ device insertion, 80 were implanted in the electrophysiology laboratory and 98 in a procedure room. There were no significant differences in baseline patient characteristics. All implants were performed in the recommended manufacturer method with the exception of 1 which required suture closure. Only a minority received peri-procedural antibiotics with a greater number in the electrophysiology laboratory group (11 [14%] versus 1 [1%], p=0.007). Overall, there were 3 (1.7%) complications with no significant difference between the electrophysiology laboratory and the procedure room groups (2 [3%] versus 1 [1%], p=0.45). There was 1 superficial infection in the procedure room group and 1 superficial infection with device extrusion and 1 traumatic extrusion in the electrophysiology laboratory group. Procedure room implantation subjectively improved laboratory efficiency and patient flow. Reveal LINQ insertion can be safely performed outside of the cardiac laboratory provided a sterile technique is followed by the operator using manufacturer recommendations for insertion. These findings have significant resource implications for hospitals undertaking such procedures.
Publisher: Elsevier BV
Date: 11-2017
DOI: 10.1016/J.PBIOMOLBIO.2017.07.010
Abstract: Atrial fibrillation (AF) is the most common sustained arrhythmia and across the developed nations, it contributes to increasing hospitalizations and healthcare burden. Several comorbidities and risk factors including hypertension, heart failure, obstructive sleep apnoea and obesity are known to play an important role in the initiation and perpetuation of AF and atrial stretch or dilatation may play a central mechanistic role. The impact of atrial stretch in the development of AF can vary dependent on the underlying disease. This review focuses on understanding the substrate for AF in conditions of acute and chronic stretch and in the presence of common co-morbidities or risk factors through the review of findings in both animal and human studies. Additionally, the reversibility of atrial remodeling following stretch release will also be discussed. Identification of clinical conditions associated with increased atrial stretch as well as the treatment or prevention of these conditions may help to prevent AF progression and improve sinus rhythm maintenance.
Publisher: BMJ
Date: 12-2022
DOI: 10.1136/BMJOPEN-2022-065407
Abstract: Atrial fibrillation (AF) is associated with increased risk of stroke, heart failure and death. Health literacy, an aspect that falls within precision health, has been recognised as an important factor. We will be focusing on the impact of these interventions specifically to AF and its health outcomes. This protocol is informed by the Preferred Reporting Items for Systematic review and Meta-Analysis Protocols. The results will be reported in line with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses to determine the impacts of health literacy interventions on AF outcomes. Searches will be carried out on databases including MEDLINE, EMBASE, Web of Science, CINAHL, Emcare, Cochrane Library and Google Scholar. Citations will be collected via Endnote 20, then into Covidence for duplicate removal, and article screening. Extraction will occur using a standardised extraction tool and studies will be synthesised using best evidence synthesis. Downs and Black's checklist will be used for risk of bias and assessment of overall quality of evidence will use the Grading of Recommendations, Assessment, Development and Evaluation approach. Approval from human research ethics committee is not required. Dissemination will occur in peer-reviewed journals and conference presentations. CRD42022304835.
Publisher: Elsevier BV
Date: 08-2016
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 11-2021
DOI: 10.1161/HYPERTENSIONAHA.121.17797
Abstract: Research links high blood pressure variability (BPV) with stroke and cerebrovascular disease, however, its association with cognition remains unclear. Moreover, it remains uncertain which BP-derived parameter (ie, variability or mean) holds more significance in understanding vascular contributions to cognitive impairment. We searched PubMed, Embase, PsycINFO, and Scopus and performed a meta-analysis of studies that quantified the association between resting BPV with dementia or cognitive impairment in adults. Two authors independently reviewed all titles, abstracts, and full-texts and extracted data, following Preferred Reporting Items for Systematic Reviews and Meta-Analyses and Meta-Analysis of Observational Studies in Epidemiology guidelines. Study quality was assessed using the (modified) Newcastle-Ottawa Scale. A multilevel meta-analysis was used, which included effect sizes for both BPV and mean BP, with a combined end point of dementia or cognitive impairment as primary outcome. In the primary analysis, 54 effect sizes were extracted from 20 studies, with a total analytical s le of n=7 899 697. Higher systolic BPV (odds ratio [OR], 1.25 [95% CI, 1.16–1.35]), mean systolic pressure (OR, 1.12 [95% CI, 1.02–1.29]), diastolic BPV (OR, 1.20 [95% CI, 1.12–1.29]), and mean diastolic pressure (OR, 1.16 [95% CI, 1.04–1.29]) were associated with dementia and cognitive impairment. A direct comparison showed that mean BP effect sizes were less strong than BPV effect sizes (OR, 0.92 [95% CI, 0.87–0.97], P .01), indicating that the relative contribution of BPV exceeded that of mean BP. Methodological and statistical heterogeneity was high. Secondary analyses were less consistent as to whether BPV and mean BP were differentially associated with dementia subtypes and cognitive domains. Future studies are required to investigate BPV as a target for dementia prevention.
Publisher: Oxford University Press (OUP)
Date: 29-06-2019
DOI: 10.1093/ICVTS/IVY191
Abstract: Atrial fibrillation is treated surgically by creating conduction block lesions. Radiofrequency (RF) lesions have reduced efficacy compared to 'cut-and-sew'. Catheter ablation studies demonstrate a relationship between lesion depth and contact force. We hypothesized that contact force and lesion depth are dependent on design of the bipolar surgical RF cl s. Hinged and parallel jaw style RF cl s were studied. Muscle s les were cl ed with pressure-sensitive film at increasing tissue thicknesses. Films were analysed determining cl pressure profiles. A sheep model was utilized for ablation testing using each cl style until the device indicated transmurality. Separate muscle areas had 1, 2 or 3 burns applied. The muscle was excised, sectioned every 1 cm and stained for lesion depth and fat thickness analysis. Pressure profiling comparing the proximal and distal segments of each cl style demonstrated only one statistically significant difference in the parallel cl the hinged cl had statistically significant differences (P ≤ 0.03) for all tissue thicknesses. There was no evidence for differences in the proximal lesion depth of both cl s (P = 0.13) but deeper distally in the parallel cl (10.17 mm vs 8.02 mm, P = 0.003). The logistic regression analysis demonstrated increased odds of transmurality with parallel cl s at 1, 2 or 3 burns (P = 0.03, P = 0.003 and P = 0.002). Every 1 mm increase in overlying fat decreased likelihood of transmurality by 11% (P < 0.05). The parallel and hinged cl s have different pressure profiles with higher likelihood of transmurality using the parallel cl . Fat reduces the ability of RF to deliver a transmural lesion. These findings have implications for optimal surgical RF ablation technique.
Publisher: Springer Science and Business Media LLC
Date: 13-04-2010
DOI: 10.1007/S10067-010-1450-2
Abstract: Cardiovascular involvement occurring in 20-30% patients is the second most common cause of mortality in patients with relapsing polychondritis. Aortic insufficiency occurs as a result of aortic root dilatation rather than primary valvular involvement. We are reporting a patient of relapsing polychondritis with aortic root dilatation, in whom institution of early and aggressive therapy successfully prevented the progression of aortic insufficiency.
Publisher: Wiley
Date: 10-2009
Publisher: Elsevier BV
Date: 07-2021
Publisher: Oxford University Press (OUP)
Date: 30-01-2020
Abstract: There is growing evidence that magnetic resonance imaging (MRI) scanning in patients with non-conditional cardiac implantable electronic devices (CIEDs) can be performed safely. Here, we aim to assess the safety of MRI in patients with non-conditional CIEDs. English scientific literature was searched using PubMed/Embase/CINAHL with keywords of ‘magnetic resonance imaging’, ‘pacemaker’, ‘implantable defibrillator’, and ‘cardiac resynchronization therapy’. Studies assessing outcomes of adverse events or significant changes in CIED parameters after MRI scanning in patients with non-conditional CIEDs were included. References were excluded if the MRI conditionality of the CIEDs was undisclosed number of patients enrolled was & or studies were case reports/series. 35 cohort studies with a total of 5625 patients and 7196 MRI scans (0.5–3 T) in non-conditional CIEDs were included. The overall incidence of lead failure, electrical reset, arrhythmia, inappropriate pacing and symptoms related to pocket heating, or torque ranged between 0% and 1.43%. Increase in pacing lead threshold & .5 V and impedance & Ω was seen in 1.1% [95% confidence interval (CI) 0.7–1.8%] and 4.8% (95% CI 3.3–6.4%) respectively. The incidence of reduction in P- and R-wave sensing by & % was 1.5% (95% CI 0.6–2.9%) and 0.4% (95% CI 0.06–1.1%), respectively. Battery voltage reduction of & .04 V was reported in 2.2% (95% CI 0.2–6.1%). This meta-analysis affirms the safety of MR imaging in non-conditional CIEDs with no death or implantable cardioverter-defibrillator shocks and extremely low incidence of lead or device-related complications.
Publisher: Oxford University Press (OUP)
Date: 17-11-2016
Abstract: Intensive research over the last few decades has seen significant advances in our understanding of the complex mechanisms underlying atrial fibrillation (AF). The epidemic of AF and related hospitalizations has been described as a 'rising tide' with estimates of the global AF burden showing no sign of retreat. There is urgency for effective translational programs in this field to facilitate more in idualized and targeted therapy to modify the abnormal atrial substrate responsible for the perpetuation of this arrhythmia. In this review, we chose to focus on several novel aspects of AF pathogenesis whereby practical applications in clinical practice are currently available or potentially not too far away. Specifically, we explored the contribution of atrial fibrosis, epicardial adipose tissue, autonomic nervous system, hyper-coagulability, and focal drivers to adverse atrial remodelling and AF persistence. We also highlighted the potential practical means of monitoring and targeting these factors to achieve better outcomes in patients suffering from this debilitating illness. Emerging data also support a new paradigm for targeting AF substrate with aggressive risk factor management. Finally, multi-disciplinary integrated care approach has shown great promise in improving cardiovascular outcomes of patients with AF along with potential cost savings.
Publisher: BMJ
Date: 10-05-2017
DOI: 10.1136/HEARTJNL-2016-310952
Abstract: Atrial fibrillation (AF) is an emerging global epidemic associated with significant morbidity and mortality. Whilst other chronic cardiovascular conditions have demonstrated enhanced patient outcomes from coordinated systems of care, the use of this approach in AF is a comparatively new concept. Recent evidence has suggested that the integrated care approach may be of benefit in the AF population, yet has not been widely implemented in routine clinical practice. We sought to undertake a systematic review and meta-analysis to evaluate the impact of integrated care approaches to care delivery in the AF population on outcomes including mortality, hospitalisations, emergency department visits, cerebrovascular events and patient-reported outcomes. PubMed, Embase and CINAHL databases were searched until February 2016 to identify papers addressing the impact of integrated care in the AF population. Three studies, with a total study population of 1383, were identified that compared integrated care approaches with usual care in AF populations. Use of this approach was associated with a reduction in all-cause mortality (OR 0.51, 95% CI 0.32 to 0.80, p=0.003) and cardiovascular hospitalisations (OR 0.58, 95% CI 0.44 to 0.77, p=0.0002) but did not significantly impact on AF-related hospitalisations (OR 0.82, 95% CI 0.56 to 1.19, p=0.29) or cerebrovascular events (OR 1.00, 95% CI 0.48 to 2.09, p=1.00). The use of the integrated care approach in AF is associated with reduced cardiovascular hospitalisations and all-cause mortality. Further research is needed to identify optimal settings, methods and components of delivering integrated care to the burgeoning AF population.
Publisher: Elsevier BV
Date: 09-2017
DOI: 10.1016/J.HLC.2014.09.012
Abstract: Catheter ablation of atrial fibrillation (AF) is an established rhythm control strategy however, the impact of co-existing LV systolic dysfunction (LVSD) on ablation success is less well understood. This systematic review compiles the outcomes of catheter ablation of atrial fibrillation in patients with LVSD. An electronic database (Pubmed, Scopus, Embase) search using the keywords 'atrial fibrillation AND ablation AND (ventricular dysfunction OR heart failure OR cardiomyopathy)' was performed for English scientific literature up to 01/01/2014. 2484 references were retrieved and evaluated for relevance by three reviewers. Reviews and reference lists of retrieved articles were also examined to ensure all relevant studies were included. Data was extracted from 19 studies, including a total of 914 patients. Single-procedure success in LVSD patients for AF ablation was 56.5% (95% CI: 48%-64%). Overall multiple-procedure (including the use of anti-arrhythmic drugs) in LVSD patients for AF ablation was 81.8% (95% CI: 75%-87%). The mean increase in LVEF following AF ablation was 13.3% (95% CI: 10.8%-15.9%). Seven studies reported improvements in exercise capacity and quality of life information using standardised criteria. The pooled rate of serious adverse events was 5.5% (95% CI: 3.7%-8.1%). Catheter ablation may be an effective therapy in AF patients with left ventricular systolic impairment, and can be associated with improvements in left ventricular function, quality of life, exercise capacity, and modest rates of serious adverse events.
Publisher: Medknow
Date: 2010
Publisher: Elsevier BV
Date: 02-2015
DOI: 10.1016/J.TCM.2014.09.005
Abstract: Obesity is a global pandemic with a huge burden on the healthcare system. Obesity is not only linked to the development of risk factors for atherosclerotic vascular disease but also has a strong association with ventricular hypertrophy, heart failure, atrial fibrillation, and stroke. Recent experimental and clinical studies have demonstrated that obesity is associated with cardiac dysfunction, adipokine dysregulation, and activation of the pro-fibrotic signaling pathways leading to cardiac fibrosis, which is a key structural change responsible for atrial fibrillation. Importantly, these also have been shown to be reversible with weight reduction strategies. This review discusses the alterations in cardiac metabolism and function due to obesity. In addition, it addresses the complex and not yet fully understood mechanisms underlying cardiac fibrosis, with a focus on atrial substrate predisposing to atrial fibrillation in obesity.
Publisher: Elsevier BV
Date: 04-2020
Publisher: Springer Science and Business Media LLC
Date: 07-04-2010
DOI: 10.1007/S10875-010-9388-3
Abstract: While the molecular basis of dilated cardiomyopathy (DCM) remains uncertain, concrete evidence is emerging that sarcomeric and cytoskeleton gene expression of myocardium isolated from failing versus non-failing patients differ dramatically. The central aim to this work was to find out the possible role of dystrophin and titin along with the TNF-alpha in the pathogenesis of cardiomyopathy. mRNA levels and protein expression of a cytoskeletal protein, dystrophin and a sarcomeric protein, titin in endomyocardial biopsies of DCM patients were examined using RT-PCR and immunohistochemistry, respectively. Further, we examined the effect of TNF-alpha on myocardial expression of titin and dystrophin in vitro in rat cardiac myoblast cell line (H9c2). We observed significantly decreased mRNA and protein levels of dystrophin and titin in endomyocardial biopsy of DCM patients as compared to control group. The decreased levels of these proteins correlated with the severity of the disease. Plasma levels of both TNF-alpha and its soluble receptors TNFR1 and TNFR2 were found to be significantly higher in patients as compared to control group. Treatment of H9c2 cells with TNF-alpha resulted in a dose- and time-dependent decrease in mRNA levels of dystrophin and titin. Pretreatment of these cells with MG132, an inhibitor of nuclear factor kappa B (NF-kappaB) pathway, abolished TNF-alpha-induced reduction in mRNA levels of dystrophin and titin. Our results suggest that reduced expression of dystrophin and titin is associated with the pathophysiology of DCM, and TNF-alpha may modulate the expression of these proteins via NF-kappaB pathway.
Publisher: Wiley
Date: 18-01-2021
DOI: 10.1111/PACE.14161
Abstract: To characterize contemporary pacemaker procedure trends. Nationwide analysis of pacemaker procedures and costs between 2008 and 2017 in Australia. The main outcome measures were total, age- and gender-specific implant, replacement, and complication rates, and costs. Pacemaker implants increased from 12,153 to 17,862. Implantation rates rose from 55.3 to 72.6 per 100,000, a 2.8% annual increase (incidence rate ratio [IRR] 1.028 95% CI, 1.02-1.04 p < .001). Pacemaker implants in the 80+ age group were 17.37-times higher than the < 50 group (95% CI 16.24-18.59 p < .001), and in males were 1.48-times higher than in females (95% CI 1.42-1.55 p < .001). However, there were similar increases according to age (p = .10) and gender (p = .68) over the study period. Left ventricular lead rates were stable (IRR 0.995 95% CI 0.98-1.01 p = .53). Generator replacements decreased from 20.5 to 18.3 per 100,000 (IRR 0.975 95% CI 0.97-0.98 p < .001). Although procedures for generator-related complications were stable (IRR 0.995 95% CI 0.98-1.01 p = .54), those for lead-related complications decreased (IRR 0.985 95% CI 0.98-0.99 p < .001). Rates for all pacemaker procedures were consistently greater in males (p < .001). Although annual costs of all pacemaker procedures increased from $178 million to $329 million, inflation-adjusted costs were more stable, rising from $294 million to $329 million. Increasing demand for pacemaker implants is driven by the ageing population and rising rates across all ages, while replacement and complication procedure rates appeared more stable. Males have consistently greater pacemaker procedure rates than females. Our findings have significant clinical and public health implications for healthcare resource planning.
Publisher: Wiley
Date: 08-05-2017
DOI: 10.1111/PACE.13073
Abstract: Medical technology has made significant advances over the last few decades with smaller and more dynamic pacemakers. However, technical failures leading to premature replacement is a cause of concern. We present a series of Medtronic EnRhythm devices that reached premature elective replacement indicator (ERI). The database of Centre of Heart Rhythm Disorders was searched for EnRhythm device implantation from 2006 to 2011. Battery depletion <8.5 years was considered premature considering the projected average longevity to be 8.5-10.5 years. An unexpected premature ERI was defined when it was reached within 3 months of last normal check. Device follow-up was conducted every 3 months after advisory. A total of 88 EnRhythm pacemakers were implanted. Over a median follow-up of 6.2 years (range: 0.3-9.2), 39 (44.3%) EnRhythm devices reached premature ERI. In 11 (28%), ERI was not recognized and patients were being investigated for other causes of unsteadiness or dyspnea prior to device check. Notably, three (7%) patients had premature ERI < 3.5 years. Ten (25.6%) had sudden and unexpected premature ERI. While asynchronous pacing was observed, there were no cases of absence of pacing. The rate of premature ERI for EnRhythm devices was 44.3%, significantly higher than reported by the manufacturer. Of concern, a sizeable proportion occurred unexpectedly, warranting more frequent reviews and empirical replacement in some patients. With the experience of the EnRhythm, appropriate monitoring strategies are recommended for future advisories.
Publisher: Wiley
Date: 04-2010
Publisher: Elsevier BV
Date: 12-2018
DOI: 10.1016/J.IJCARD.2018.07.124
Abstract: Sleep-disordered breathing (SDB) is highly prevalent in patients with atrial fibrillation (AF) and its treatment can improve rhythm control. Polysomnography (PSG) is the gold standard for the diagnosis of SDB but its high cost and limited availability constrain its role as a standard SDB screening tool. We sought to assess the diagnostic utility of overnight oximetry in predicting SDB in AF patients. We analyzed prospectively collected data on 439 patients with documented AF (62% paroxysmal AF) who underwent PSG. Overnight oximetry was used to determine the oxygen desaturation index (ODI, number of desaturation/h) by a novel automated computer algorithm. ODI was validated against PSG derived apnea-hypopnea index (AHI). The s le consisted of 69% men with a mean age of 59.9 ± 11.3 years and body mass index of 30 ± 5 kg/m ODI derived from a simple and low-cost overnight oximetry can be used as an accessible and reliable screening tool, particularly to rule out SDB.
Publisher: Elsevier BV
Date: 04-2020
Publisher: Elsevier BV
Date: 05-2017
DOI: 10.1016/J.JACEP.2016.12.015
Abstract: Atrial fibrillation (AF) imposes a substantial cost burden on the healthcare system. Weight and risk factor management (RFM) reduces AF burden and improves the outcomes of AF ablation. This study sought to evaluate the cost and clinical effectiveness of integrating RFM into the overall management of AF. Of 1,415 consecutive patients with symptomatic AF, 825 patients had body mass index ≥27 kg/m There were no differences in baseline characteristics or follow-up duration (p = NS). Arrhythmia-free survival was better in the RFM compared with control subjects (Kaplan-Meier: 79% vs. 44% p < 0.001). At follow-up, RFM group had less unplanned specialist visits (0.19 ± 0.40 vs. 1.94 ± 2.00 p < 0.001), hospitalizations (0.74 ± 1.3 vs. 1.05 ± 1.60 p = 0.03), cardioversions (0.89 ± 1.50 vs. 1.51 ± 2.30 p = 0.002), emergency presentations (0.18 ± 0.50 vs. 0.76 ± 1.20 p < 0.001), and ablation procedures (0.60 ± 0.69 vs. 0.72 ± 0.86 p = 0.03). Antihypertensive (0.53 ± 0.70 vs. 0.78 ± 0.60 p = 0.04) and antiarrhythmic (0.26 ± 0.50 vs. 0.91 ± 0.60 p = 0.003) use declined in RFM. The RFM group had an increase of 0.1930 quality-adjusted life years and a cost saving of $12,094 (incremental cost-effectiveness ratios of $62,653 saved per quality-adjusted life years gained). A structured physician-directed RFM program is clinically effective and cost saving.
Publisher: Elsevier BV
Date: 09-2015
DOI: 10.1016/J.JACC.2015.06.488
Abstract: Obesity begets atrial fibrillation (AF). Although cardiorespiratory fitness is protective against incident AF in obese in iduals, its effect on AF recurrence or the benefit of cardiorespiratory fitness gain is unknown. This study sought to evaluate the role of cardiorespiratory fitness and the incremental benefit of cardiorespiratory fitness improvement on rhythm control in obese in iduals with AF. Of 1,415 consecutive patients with AF, 825 had a body mass index ≥27 kg/m(2) and were offered risk factor management and participation in a tailored exercise program. After exclusions, 308 patients were included in the analysis. Patients underwent exercise stress testing to determine peak metabolic equivalents (METs). To determine a dose response, cardiorespiratory fitness was categorized as: low ( 100%). Impact of cardiorespiratory fitness gain was ascertained by the objective gain in fitness at final follow-up (≥2 METs vs. <2 METs). AF rhythm control was determined using 7-day Holter monitoring and AF severity scale questionnaire. There were no differences in baseline characteristics or follow-up duration between the groups defined by cardiorespiratory fitness. Arrhythmia-free survival with and without rhythm control strategies was greatest in patients with high cardiorespiratory fitness compared to adequate or low cardiorespiratory fitness (p < 0.001 for both). AF burden and symptom severity decreased significantly in the group with cardiorespiratory fitness gain ≥2 METs as compared to <2 METs group (p < 0.001 for all). Arrhythmia-free survival with and without rhythm control strategies was greatest in those with METs gain ≥2 compared to those with METs gain <2 in cardiorespiratory fitness (p < 0.001 for both). Cardiorespiratory fitness predicts arrhythmia recurrence in obese in iduals with symptomatic AF. Improvement in cardiorespiratory fitness augments the beneficial effects of weight loss. (Evaluating the Impact of a Weight Loss on the Burden of Atrial Fibrillation [AF] in Obese Patients ACTRN12614001123639).
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 08-2019
DOI: 10.1161/CIRCEP.118.007005
Abstract: The posterior left atrium is an arrhythmogenic substrate that contributes to the initiation and maintenance of atrial fibrillation (AF) however, the feasibility, safety, and efficacy of posterior wall isolation (PWI) as an AF ablation strategy has not been widely reported. We undertook a systematic review and meta-analysis of studies performing PWI to assess (1) acute procedural success including the ability to achieve PWI and the number of procedure-related complications, (2) Long-term, clinical success including rates of arrhythmia recurrence and posterior wall reconnection, and (3) The efficacy of PWI compared with pulmonary vein isolation on preventing arrhythmia recurrence. MEDLINE, EMBASE, and Web of Science databases were searched in May 2018 to retrieve relevant studies. Results were pooled using a random effects model. Seventeen studies (13 box isolation, 3 single ring isolation, and 1 debulking ablation) comprising 1643 patients (31.3% paroxysmal AF, left atrial diameter 41±3.1 mm) were included in the final analysis. In studies focusing specifically on PWI, the acute procedural success rate for achieving PWI was 94.1% (95% CI, 87.2%–99.3%). Single-procedure 12-month freedom from atrial arrhythmia was 65.3% (95% CI, 57.7%–73.9%) overall and 61.9% (54.2%–70.8%) for persistent AF. Randomized control trials comparing PWI to pulmonary vein isolation (3 studies, 444 patients) yielded conflicting results and could not confirm an incremental benefit to PWI. Fifteen major complications (0.1%), including 2 atrio-esophageal fistulas, were reported. PWI as an end point of AF ablation can be achieved in a large proportion of cases with good rates of 12-month freedom from atrial arrhythmia. Although the procedure-related complication rate is low, it did not eliminate the risk of atrio-esophageal fistula. URL: www.crd.york.ac.uk rospero . PROSPERO registration number: CRD42018107212.
Publisher: BMJ
Date: 20-05-2014
Publisher: Springer Science and Business Media LLC
Date: 05-2011
DOI: 10.1007/S00246-011-9998-4
Abstract: A congenital left ventricular erticulum is a rare cardiac malformation. It is a developmental anomaly that occurs during embryogenesis. Presentations vary from asymptomatic patients to sudden death. To date, the treatment described has been surgical correction. The authors report the first transcatheter closure of an isolated congenital left ventricular erticulum in a 12-year-old symptomatic girl.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 24-09-2019
DOI: 10.1161/CIRCULATIONAHA.119.041320
Abstract: Atrial arrhythmias are common in patients with implantable cardioverter-defibrillator (ICD). External shocks and internal cardioversion through commanded ICD shock for electrical cardioversion are used for rhythm-control. However, there is a paucity of data on efficacy of external versus internal cardioversion and on the risk of lead and device malfunction. We hypothesized that external cardioversion is noninferior to internal cardioversion for safety, and superior for successful restoration of sinus rhythm. Consecutive patients with ICD undergoing elective cardioversion for atrial arrhythmias at 13 centers were randomized in 1:1 fashion to either internal or external cardioversion. The primary safety end point was a composite of surrogate events of lead or device malfunction. Conversion of atrial arrhythmia to sinus rhythm was the primary efficacy end point. Myocardial damage was studied by measuring troponin release in both groups. N=230 patients were randomized. Shock efficacy was 93% in the external cardioversion group and 65% in the internal cardioversion group ( P .001). Clinically relevant adverse events caused by external or internal cardioversion were not observed. Three cases of pre-existing silent lead malfunction were unmasked by internal shock, resulting in lead failure. Troponin release did not differ between groups. This is the first randomized trial on external vs internal cardioversion in patients with ICDs. External cardioversion was superior for the restoration of sinus rhythm. The unmasking of silent lead malfunction in the internal cardioversion group suggests that an internal shock attempt may be reasonable in selected ICD patients presenting for electrical cardioversion. URL: www.clinicaltrials.gov . Unique identifier: NCT03247738.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 12-2016
DOI: 10.1161/CIRCEP.116.004378
Abstract: Although adiposity is increasingly recognized as a risk factor for atrial fibrillation (AF), the importance of epicardial fat compared with other adipose tissue depots remains uncertain. We sought to characterize and compare the associations of AF with epicardial fat and measures of abdominal and overall adiposity. We conducted a meta-analysis of 63 observational studies including 352 275 in iduals, comparing AF risk for 1-SD increases in epicardial fat, waist circumference, waist/hip ratio, and body mass index. A 1-SD higher epicardial fat volume was associated with a 2.6-fold higher odds of AF (odds ratio, 2.61 95% confidence interval [CI], 1.89–3.60), 2.1-fold higher odds of paroxysmal AF (odds ratio, 2.14 95% CI, 1.45–3.16) and, 5.4-fold higher odds of persistent AF (odds ratio, 5.43 95% CI, 3.24–9.12) compared with sinus rhythm. Likewise, a 1-SD higher epicardial fat volume was associated with 2.2-fold higher odds of persistent compared with paroxysmal AF (odds ratio, 2.19 95% CI, 1.66–2.88). Similar associations existed for postablation, postoperative, and postcardioversion AF. In contrast, associations of abdominal and overall adiposity with AF were less extreme, with relative risks per 1-SD higher values of 1.32 (95% CI, 1.25–1.41) for waist circumference, 1.11 (95% CI, 1.08–1.14) for waist/hip ratio, and 1.22 (95% CI, 1.17–1.27) for body mass index. Strong and graded associations were observed between increasing epicardial fat and AF. Moreover, the strength of associations of AF with epicardial fat is greater than for measures of abdominal or overall adiposity. Further studies are needed to assess the mechanisms and clinical relevance of epicardial fat.
Publisher: Elsevier BV
Date: 09-2017
Publisher: Wiley
Date: 02-02-2021
DOI: 10.1111/JCE.14898
Publisher: BMJ
Date: 21-09-2019
DOI: 10.1136/HEARTJNL-2017-312932
Abstract: Mitral valve prolapse (MVP) is commonly observed as a benign finding. However, the literature suggests that it may be associated with sudden cardiac death (SCD). We performed a meta-analysis and systematic review to determine the: (1) prevalence of MVP in the general population (2) prevalence of MVP in all SCD and unexplained SCD (3) incidence of SCD in MVP and (4) risk factors for SCD. The English medical literature was searched for: (1) MVP community prevalence (2) MVP prevalence in SCD cohorts (3) incidence SCD in MVP and (4) SCD risk factors in MVP. Thirty-four studies were identified for inclusion. This study was registered with PROSPERO (CRD42018089502). The prevalence of MVP was 1.2% (95% CI 0.5 to 2.0) in community populations. Among SCD victims, the cause of death remained undetermined in 22.1% (95% CI 13.4 to 30.7) of these, MVP was observed in 11.7% (95% CI 5.8 to 19.1). The incidence of SCD in the MVP population was 0.14% (95% CI 0.1 to 0.3) per year. Potential risk factors for SCD include bileaflet prolapse, ventricular fibrosis complex ventricular ectopy and ST-T wave abnormalities. The high prevalence of MVP in cohorts of unexplained SCD despite low population prevalence provides indirect evidence of an association of MVP with SCD. The absolute number of people exposed to the risk of SCD is significant, although the incidence of life-threatening arrhythmic events in the general MVP population remains low. High-risk features include bileaflet prolapse, ventricular fibrosis, ST-T wave abnormalities and frequent complex ventricular ectopy. PROSPERO (CRD42018089502).
Publisher: Elsevier BV
Date: 11-2016
DOI: 10.1016/J.CCL.2016.06.006
Abstract: Exercise training has considerable health benefits. However, recent research has demonstrated a greater risk of atrial arrhythmias in endurance athletes. The mechanisms promoting atrial fibrillation in athletes are unclear but there seems to be a central role for atrial remodeling, accompanied by autonomic alterations and inflammation. Animal studies have provided unique insights, yet prospective human data are lacking. Treatment options seem to yield similar efficacy to that seen in a nonathletic population and may be justified as an early rhythm control strategy. Further studies are required to enhance understanding of the cardiac adaptations to intensive exercise training.
Publisher: No publisher found
Date: 2017
Publisher: Elsevier BV
Date: 09-2018
Publisher: Elsevier BV
Date: 06-2019
DOI: 10.1016/J.JACEP.2019.03.005
Abstract: This study sought to determine night-to-night variability in the severity of sleep-disordered breathing (SDB) and the dynamic intrain idual relationship to daily risk of incident atrial fibrillation (AF) by using simultaneous long-term day-by-day SDB and AF monitoring. Night-to-night variability in SDB severity may result in a dynamic exposure to SDB related conditions impacting the timing and extent of cardiovascular responses. This study was an observational cohort study. Daily data for AF burden and average respiratory disturbance index (RDI) were extracted from pacemakers capable of monitoring nightly SDB and daily AF burden in 72 patients. Nightly RDI values were grouped into quartiles of severity within each patient. AF burdens of >5 min, >1 h, and >12 h were the outcome variables. A total of 32% of patients had a mean RDI of ≥20/h, indicative of overall severe SDB. There was significant night-to-night variation in RDI reflected by an absolute SD of ±6.3 events/h (range 2 to 14 events/h) within any given patient. Within each patient, the nights with the highest RDI (in their highest quartile) conferred a 1.7-fold (1.2 to 2.2 p < 0.001), 2.3-fold (1.6 to 3.5 p < 0.001), and 10.2-fold (3.5 to 29.9 p < 0.001) increase risk of having at least 5 min, 1 h, and 12 h, respectively, of AF during the same day compared with the best sleep nights (in their lowest quartiles). There is considerable night-to-night variability in SDB severity which cannot be detected by 1 single overnight sleep study. SDB burden may be a better metric with which to assess the extent of dynamic SDB related cardiovascular responses such as daily AF risk than the categorical diagnosis of SDB. (Night-to-Night Variability in Severity of Sleep Apnea and Daily Dynamic Atrial Fibrillation Risk [VARIOSA-AF] ACTRN 12618000757213).
Publisher: Elsevier BV
Date: 11-2015
Publisher: Elsevier BV
Date: 02-2015
DOI: 10.1016/J.CJCA.2014.10.027
Abstract: The ever-increasing prevalence of obesity poses a significant burden on the health care system with escalating socioeconomic consequences. At the in idual level, obesity is well recognized to increase morbidity and mortality. Not only is obesity an established cardiovascular risk factor, it also increases the risk of sudden cardiac death and atrial fibrillation. Studies have shown that increased adiposity itself and the accompanying metabolic consequences of weight gain contribute to an abnormal arrhythmogenic substrate. In this review, we focus on the erse mechanisms underlying cardiac arrhythmias related to obesity. In particular, we highlight the pathogenic role of adipose depots leading to increased atrial fibrillation and the effect of weight reduction in decreasing atrial fibrillation burden in obese in iduals.
Publisher: Elsevier BV
Date: 2016
Publisher: Elsevier BV
Date: 2017
Publisher: Springer Science and Business Media LLC
Date: 29-08-2013
Abstract: Recently pericardial adipose tissue (PAT) has been shown to be an independent predictor of atrial fibrillation (AF). Atrial PAT may influence underlying atrial musculature creating a substrate for AF. This study sought to validate the assessment of total and atrial PAT by standard cardiovascular magnetic resonance (CMR) measures and describe and validate a three dimensional atrial PAT model. 10 merino cross sheep underwent CMR using a 1.5 Tesla system (Siemens, Sonata, Erlangen, Germany). Atrial and ventricular short axis (SA) images were acquired, using ECG -gated steady state free precession sequences. In order to quantify total volume of adipose tissue, a three dimensional model was constructed from consecutive end-diastolic images using semi-automated software. Regions of adipose tissue were marked in each slice followed by linear interpolation of pixel intensities in spaces between consecutive image slices. Total volume of adipose tissue was calculated as a total volume of the three dimensional model and the mass estimated from volume measurements. The sheep were euthanized and pericardial adipose tissue was removed and weighed for comparison to the corresponding CMR measurements. All CMR adipose tissue estimates significantly correlated with autopsy measurements (ICC 0.80 p 0.03). Intra- observer reliability in CMR measures was high, with 95% levels of agreement within 5.5% (ICC = 0.995) for total fat mass and its in idual atrial (95% CI ± 8.3%, ICC = 0.993) and ventricular components (95% CI ± 6.6%, ICC = 0.989). Inter- observer 95% limits of agreement were within ± 10.7% (ICC = 0.979), 7.4% (ICC = 0.991) and 7.2% (ICC = 0.991) for atrial, ventricular and total pericardial adipose tissue, respectively. This study validates the use of a semi-automated three dimensional atrial PAT model utilizing standard (clinical) CMR sequences for accurate and reproducible assessment of atrial PAT. The measurement of local cardiac fat stores via this methodology could provide a sensitive tool to examine the regional effect of fat deposition on atrial substrate which potentially may influence AF ablation strategies in obese patients.
Publisher: No publisher found
Date: 2003
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 04-12-2018
Abstract: The relationship between mitral valve prolapse ( MVP ) and sudden cardiac death ( SCD ) remains controversial. In this systematic review, we evaluate the relationship between isolated MVP and SCD to better define a potential high‐risk subtype. In addition, we determine whether premortem parameters could predict SCD in patients with MVP and the incidence of SCD in MVP . Electronic searches were conducted in PubMed and Embase for all English literature articles published between 1960 and 2018 regarding MVP and SCD or cardiac arrest. We also identified articles investigating predictors of ventricular arrhythmias or SCD and cohort studies reporting SCD outcomes in MVP . From 2180 citations, there were 79 articles describing 161 cases of MVP with SCD or cardiac arrest. The median age was 30 years and 69% of cases were female. Cardiac arrest occurred during situations of stress in 47% and was caused by ventricular fibrillation in 81%. Premature ventricular complexes on Holter monitoring (92%) were common. Most cases had bileaflet involvement (70%) with redundancy (99%) and nonsevere mitral regurgitation (83%). From 22 articles describing predictors for ventricular arrhythmias or SCD in MVP , leaflet redundancy was the only independent predictor of SCD . The incidence of SCD with MVP was estimated at 217 events per 100 000 person‐years. Isolated MVP and SCD predominantly affects young females with redundant bileaflet prolapse, with cardiac arrest usually occurring as a result of ventricular arrhythmias. To better understand the complex relationship between MVP and SCD , standardized reporting of clinical, electrophysiological, and cardiac imaging parameters with longitudinal follow‐up is required.
Publisher: Oxford University Press (OUP)
Date: 07-2015
DOI: 10.5665/SLEEP.4796
Publisher: Elsevier BV
Date: 05-2021
Publisher: Oxford University Press (OUP)
Date: 21-01-2022
Abstract: To systematic review and meta-analyse the association and mechanistic links between atrial fibrillation (AF) and cognitive impairment. PubMed, EMBASE, and Cochrane Library were searched up to 27 March 2021 and yielded 4534 citations. After exclusions, 61 were analysed 15 and 6 studies reported on the association of AF and cognitive impairment in the general population and post-stroke cohorts, respectively. Thirty-six studies reported on the neuro-pathological changes in patients with AF of those, 13 reported on silent cerebral infarction (SCI) and 11 reported on cerebral microbleeds (CMB). Atrial fibrillation was associated with 39% increased risk of cognitive impairment in the general population [n = 15: 2 822 974 patients hazard ratio = 1.39 95% confidence interval (CI) 1.25–1.53, I2 = 90.3% follow-up 3.8–25 years]. In the post-stroke cohort, AF was associated with a 2.70-fold increased risk of cognitive impairment [adjusted odds ratio (OR) 2.70 95% CI 1.66–3.74, I2 = 0.0% follow-up 0.25–3.78 years]. Atrial fibrillation was associated with cerebral small vessel disease, such as white matter hyperintensities and CMB (n = 8: 3698 patients OR = 1.38 95% CI 1.11–1.73, I2 = 0.0%), SCI (n = 13: 6188 patients OR = 2.11 95% CI 1.58–2.64, I2 = 0%), and decreased cerebral perfusion and cerebral volume even in the absence of clinical stroke. Atrial fibrillation is associated with increased risk of cognitive impairment. The association with cerebral small vessel disease and cerebral atrophy secondary to cardioembolism and cerebral hypoperfusion may suggest a plausible link in the absence of clinical stroke. PROSPERO CRD42018109185.
Publisher: SAGE Publications
Date: 07-2010
DOI: 10.1097/IMI.0B013E3181F01FA1
Abstract: Because the use of percutaneous intervention is increasing for the closure of the patent ductus arteriosus, the procedure-related complications are also on rise, with migration of the device being most common. The routine practice is to remove the migrated duct occluder device under cardiopulmonary bypass. Amplatzer duct occluder used in a 4-month-old infant dislodged into the descending thoracic aorta. It was removed by the posterolateral thoracotomy under mild hypothermia through juxtaductal aortotomy between the aortic cross-cl s. The use of cardiopulmonary bypass is thus avoided.
Publisher: Elsevier BV
Date: 09-2017
DOI: 10.1016/J.IJCARD.2017.05.012
Abstract: A number of cardiovascular diseases have been linked with bone health and an increased risk of osteoporotic fracture. Whether atrial fibrillation (AF) is associated with subsequent fracture risk is not known. Administrative, clinical and hospitalisation information were linked over a 14-year period. From this longitudinal, population-based dataset of 113,600 in iduals, time-dependent exposures using multivariate Cox proportional hazards regression models were employed to determine incidence rates and hazard ratios (HR) for hip fracture according to a history of AF. The annualised incidence rate for hip fracture was 7.4 per 1000 person-years (95% CI 7.1-7.7) in those without AF and 17.5 per 1000 person-years (95% CI 16.8-18.1) in those with AF. Compared to in iduals without AF, those with AF were more likely to develop incident hip fracture in both men (unadjusted HR 2.39 [95% CI 1.96-2.91]) and women (unadjusted HR 2.91 [95% CI 2.55-3.34]). After adjusting for potential confounders, these associations were attenuated but remained statistically significant (adjusted HR 1.97 [95% CI 1.61-2.42] in men adjusted HR 2.08 [95% CI 1.80-2.39] in women). A history of AF was associated with an increased risk of hip fracture in this large, population-based analysis. This association appeared to remain significant even after adjusting for potential confounders such as age, comorbidities and medication use. Patients with a history of AF may represent a clinical population in whom screening for and treatment of osteoporosis may be warranted to reduce the risk of subsequent fracture.
Publisher: Elsevier BV
Date: 11-2017
DOI: 10.1016/J.IJCARD.2017.05.133
Abstract: Whilst high levels of alcohol consumption are known to be associated with atrial fibrillation (AF), it is unclear if any level of alcohol consumption can be recommended to prevent the onset of the condition. The aim of this review is to characterise the association between chronic alcohol intake and incident AF. Electronic literature searches were undertaken using PubMed and Embase databases up to 1 February 2016 to identify studies examining the impact of alcohol on the risk of incident AF. Prospective studies reporting on at least three levels of alcohol intake and published in English were eligible for inclusion. Studies of a retrospective or case control design were excluded. The primary study outcome was development of incident AF. Consistent with previous studies, high levels of alcohol intake were associated with an increased incident AF risk (HR 1.34, 95% CI 1.20-1.49, p<0.001). Moderate levels of alcohol intake were associated with a heightened AF risk in males (HR 1.26, 95% CI 1.04-1.54, p=0.02) but not females (HR 1.03, 95% CI 0.86-1.25, p=0.74). Low alcohol intake, of up to 1 standard drink (SD) per day, was not associated with AF development (HR 0.95, 95% CI 0.85-1.06, p=0.37). Low levels of alcohol intake are not associated with the development of AF. Gender differences exist in the association between moderate alcohol intake and AF with males demonstrating greater increases in risk, whilst high alcohol intake is associated with a heightened AF risk across both genders.
Publisher: Elsevier BV
Date: 04-2019
DOI: 10.1016/J.HLC.2018.03.024
Abstract: Recent registry data suggests oral anticoagulation (OAC) usage remains suboptimal in atrial fibrillation (AF) patients. The aim of our study was to determine if rates of appropriate use of OAC in in iduals with AF differs between the emergency department (ED) and cardiac outpatient clinic (CO). This was a retrospective study of consecutive AF patients over a 12-month period. Data from clinical records, discharge summaries and outpatient letters were independently reviewed by two investigators. Appropriateness of OAC was assessed according to the CHA Of 455 unique ED presentations with AF as a primary diagnosis, 115 patients who were treated and discharged from the ED were included. These were compared to 259 consecutively managed AF patients from the CO. Inappropriate OAC was significantly higher in the ED compared to the CO group (65 vs. 18%, p<0.001). Treatment in the ED was a significant multivariate predictor of inappropriate OAC (odds ratio 8.2 [4.8-17.7], p<0.001). This patient level data highlights that significant opportunity exists to improve disparities in the use of guideline adherent therapy in the ED compared to CO. There is an urgent need for protocol-driven treatment in the ED or streamlined early follow-up in a specialised AF clinic to address this treatment gap.
Publisher: Oxford University Press (OUP)
Date: 10-01-2018
Abstract: To determine stroke risk in subclinical atrial fibrillation (AF) and temporal association between subclinical AF and stroke. Pubmed/Embase was searched for studies reporting stroke in subclinical AF in patients with cardiac implantable electronic devices (CIEDs). After exclusions, 11 studies were analysed. Of these seven studies reported prevalence of subclinical AF, two studies reported association between subclinical and clinical AF, seven studies reported stroke risk in subclinical AF, and five studies reported temporal relationship between subclinical AF and stroke. Subclinical AF was noted after CIEDs implant in 35% [interquartile range (IQR) 34-42] of unselected patients with pacing indication over 1-2.5 years. The definition and cut-off duration (for stroke risk) of subclinical AF varied across studies. Subclinical AF was strongly associated with clinical AF (OR 5.7, 95% CI 4.0-8.0, P defined cut-off duration was 1.89/100 person-year (95% CI 1.02-3.52) with 2.4-fold (95% CI 1.8-3.3, P < 0.001, I2 = 0%) increased risk of stroke as compared to patients with subclinical AF < cut-off duration (absolute risk was 0.93/100 person-year). Three studies provided mean CHADS2 score. In these studies, with mean CHADS2 score of 2.1 ± 0.1, subclinical AF was associated with annual stroke rate of 2.76/100 person-years (95% CI 1.46-5.23). After excluding patients without AF, only 17% strokes occurred in presence of ongoing AF. Subclinical AF was noted in 29% [IQR 8-57] within 30 days preceding stroke. Subclinical AF strongly predicts clinical AF and is associated with elevated absolute stroke risk albeit lower than risk described for clinical AF.
Publisher: Elsevier BV
Date: 2016
Publisher: Elsevier BV
Date: 07-2015
DOI: 10.1016/J.IJCARD.2015.03.064
Abstract: Atrial fibrillation (AF) is a leading cause of preventable stroke in Australia. Given that anticoagulation therapy can significantly reduce this stroke risk, we sought to characterise anticoagulation use in Indigenous and non-Indigenous Australians with AF. Administrative, clinical and prescription data from patients with AF were linked. Anticoagulation use was characterised according to guideline-recommended risk scores and Indigenous status. 19,613 in iduals with AF were studied. Despite a greater prevalence of other risk factors, Indigenous Australians were significantly younger than their non-Indigenous counterparts (p<0.001) and thus had lower CHADS₂- (1.19±0.32 vs 1.99±0.47, p<0.001) and CHA₂DS₂VASc-scores (1.47 ± 0.03 vs 2.82 ± 0.08, p<0.001). Correspondingly, the percentage of Indigenous Australians with CHADS₂ ≥ 2 (39.6% vs 44.1%, p<0.001) and CHA₂DS₂VASc-scores ≥ 2 (62.9% vs 78.8%, p<0.001) was also lower. Indigenous Australians, however, had greater rates of under- and over-anticoagulation. Overall, 72.1% and 68.9% of Indigenous and non-Indigenous Australians with CHADS₂ scores ≥2, and 76.3% and 71.3% with CHA₂DS₂VASc scores ≥2, were under-anticoagulated. Similarly, 27.4% and 24.1% of Indigenous and non-Indigenous Australians with CHADS₂ scores=0, and 24.0% and 16.7% with CHA₂DS₂VASc-scores=0, were over-anticoagulated. In multivariate analyses, Indigenous Australians were more likely to receive under- or over-anticoagulation according to CHADS₂- or CHA₂DS₂VASc-score (p=0.045 and p<0.001 respectively). Anticoagulation for AF is frequently not prescribed in accordance with guideline recommendations. Under-anticoagulation in those at high stroke risk, and over-anticoagulation in those at low risk, is common and more likely in Indigenous patients with AF. Improving adherence to guideline recommendations for anticoagulation in AF may reduce both ischaemic and haemorrhagic strokes in Indigenous and non-Indigenous Australians.
Publisher: BMJ
Date: 17-09-2019
DOI: 10.1136/HEARTJNL-2019-314770
Abstract: The aim of the meta-analysis was to determine the association of obesity and heart failure (HF) and the cardiac impact of intentional weight loss following bariatric surgery on cardiac structure and myocardial function in obese subjects. MEDLINE, Embase and Web of Science were searched up to 3 April 2018. Studies reporting association and prognostic impact of obesity in HF and the impact of intentional weight loss following bariatric surgery on cardiac structure and myocardial function in obesity were included in the meta-analysis. 4959 citations were reviewed. After exclusions, 29 studies were analysed. A ‘J curve’ relationship was observed between body mass index (BMI) and risk of HF with maximum risk in the morbidly obese (1.73 (95% CI 1.30 to 2.31), p .001, n=11). Although ‘obesity paradox’ was observed for all-cause mortality, the overweight group was associated with lower cardiovascular (CV) mortality (OR=0.86 (95% CI 0.79 to 0.94), n=11) with no significant differences across other BMI groups. Intentional weight loss induced by bariatric surgery in obese patients (n=9) without established HF, atrial fibrillation or known coronary artery disease, was associated with a reduction in left ventricular mass index (p .0001), improvement in left ventricular diastolic function (p≤0.0001) and a reduction in left atrial size (p=0.02). Despite the increased risk of HF with obesity, an ‘obesity paradox’ is observed for all-cause mortality. However, the nadir for CV mortality is observed in the overweight group. Importantly, intentional weight loss was associated with improvement in indices of cardiac structure and myocardial function in obese patients. APP 74412.
Publisher: Informa UK Limited
Date: 08-03-2017
DOI: 10.1080/14779072.2017.1299005
Abstract: Recent research has unravelled an increasing list of cardiac conditions and risk factors that may be responsible for the abnormal underlying atrial substrate that predisposes to atrial fibrillation (AF). Atrial fibrosis has been demonstrated as the pivotal structural abnormality underpinning conduction disturbances that promote AF in different disease models. Despite the advancement in our discoveries of the molecular mechanisms involved in the profibrotic milieu, targeted therapeutics against atrial fibrosis remain lacking. Areas covered: This review is focused on detailing the key molecular signalling pathways that contribute to atrial fibrosis including: angiotensin II, transforming growth factor (TGF- ß1), connective tissue growth factor (CTGF) and endothelin-1. We also discussed the potential therapeutic options that may be useful in modulating the abnormal atrial substrate. In addition, we examined the new paradigm of AF care in lifestyle and risk factor management that has been shown to arrest and reverse the atrial remodelling process leading to improved AF outcomes. Expert commentary: The future of AF care is likely to require an integrated approach consisting of aggressive risk factor management in addition to the established paradigm of rate and rhythm management and anticoagulation. Translational studies on molecular therapeutics to combat atrial fibrosis is urgently needed.
Publisher: BMJ
Date: 25-01-2022
Publisher: Ubiquity Press, Ltd.
Date: 11-07-2017
DOI: 10.5334/IJIC.3221
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 07-01-2016
Abstract: Research links blood pressure variability ( BPV ) with stroke however, the association with cerebral small‐vessel disease ( CSVD ) remains unclear. As BPV and mean blood pressure are interrelated, it remains uncertain whether BPV adds additional information to understanding cerebrovascular morphological characteristics. A systematic review was performed from inception until March 3, 2019. Eligibility criteria included population, adults without stroke ( weeks) exposure, BPV quantified by any metric over any duration comparison, (1) low versus high or mean BPV and (2) people with versus without CSVD and outcomes, (1) CSVD as subcortical infarct, lacunae, white matter hyperintensities, cerebral microbleeds, or enlarged perivascular spaces and (2) standardized mean difference in BPV . A total of 27 articles were meta‐analyzed, comprising 12 309 unique brain scans. A total of 31 odds ratios ( OR s) were pooled, indicating that higher systolic BPV was associated with higher odds for CSVD ( OR, 1.27 95% CI, 1.14–1.42 I 2 =85%) independent of mean systolic pressure. Likewise, higher diastolic BPV was associated with higher odds for CSVD ( OR, 1.30 95% CI, 1.14–1.48 I 2 =53%) independent of mean diastolic pressure. There was no evidence of a pairwise interaction between systolic/diastolic and BPV /mean OR s ( P =0.47), nor a difference between BPV versus mean pressure OR s ( P =0.58). Fifty‐four standardized mean differences were pooled and provided similar results for pairwise interaction ( P =0.38) and difference between standardized mean differences ( P =0.70). On the basis of the available studies, BPV was associated with CSVD independent of mean blood pressure. However, more high‐quality longitudinal data are required to elucidate whether BPV contributes unique variance to CSVD morphological characteristics.
Publisher: Elsevier BV
Date: 06-2020
Publisher: Informa UK Limited
Date: 08-11-2015
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 02-2013
DOI: 10.1161/CIRCEP.112.976654
Abstract: The pivot is critical to rotors postulated to maintain atrial fibrillation (AF). We reasoned that wavefronts circling the pivot should broaden the litude distribution of bipolar electrograms because of directional information encoded in these signals. We aimed to determine whether Shannon entropy (ShEn), a measure of signal litude distribution, could differentiate the pivot from surrounding peripheral regions and thereby assist clinical rotor mapping. Bipolar electrogram recordings were studied in 4 systems: (1) computer simulations of rotors in a 2-dimensional atrial sheet (2) isolated rat atria recorded with a multi-electrode array (n=12) (3) epicardial plaque recordings of induced AF in hypertensive sheep (n=11) and (4) persistent AF patients (n=10). In the model systems, rotation episodes were identified, and ShEn calculated as an index of litude distribution. In humans, ShEn distribution was analyzed at AF termination sites and with respect to complex fractionated electrogram mean. We analyzed rotation episodes in simulations (4 cycles) and animals (rats: 14 rotors, duration 80±81 cycles sheep: 13 rotors, 4.2±1.5 cycles). The maximum ShEn bipole was consistently colocated with the pivot zone. ShEn was negatively associated with distance from the pivot zone in simulated spiral waves, rats, and sheep. ShEn was modestly inversely associated with complex fractionated electrogram however, there was no relationship at the sites of highest ShEn. ShEn is a mechanistically based tool that may assist AF rotor mapping.
Publisher: Springer Science and Business Media LLC
Date: 19-03-2009
Publisher: OMICS Publishing Group
Date: 04-2013
DOI: 10.2217/ICA.13.2
Publisher: Elsevier BV
Date: 11-2020
Publisher: Elsevier BV
Date: 2020
DOI: 10.1016/J.ORCP.2019.12.001
Abstract: Obesity is prevalent in Indigenous populations who exhibit significant differences in body fat composition. While excess regional adiposity can be partially inferred from clinical measurements, noninvasive imaging allows for direct quantification of specific fat depots. Epicardial fat is a visceral adipose tissue that has been strongly associated with cardiometabolic disease in other populations. However, this ectopic fat depot has yet to be characterized in Indigenous populations. We studied 100 in iduals matched for ethnicity (Indigenous Australian and Caucasian descent), age, gender, and body mass index. Epicardial and subcutaneous adipose tissue volumes was quantified with computed tomography. Associations of ethnicity and adiposity measures were assessed using linear regression. Indigenous in iduals had significantly greater epicardial fat volumes compared to non-Indigenous in iduals (95.8±37.5 vs 54.1±27.6cm Indigenous in iduals have significantly greater epicardial fat, but similar subcutaneous fat volumes, compared to non-Indigenous in iduals. This finding extends previous observations on body fat composition differences in these in iduals, and supports the possibility that epicardial fat and other visceral adipose depots may be contributing to the greater burden of cardiovascular disease in Indigenous populations.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 02-02-2016
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 22-09-2017
Abstract: Besides hypertension, obesity and the metabolic syndrome have recently emerged as risk factors for atrial fibrillation. This study sought to delineate the development of an arrhythmogenic substrate for atrial fibrillation in hypertension with and without concomitant obesity and metabolic syndrome. We compared obese spontaneously hypertensive rats ( SHR ‐obese, n=7–10) with lean hypertensive controls ( SHR ‐lean, n=7–10) and normotensive rats (n=7–10). Left atrial emptying function (MRI) and electrophysiological parameters were characterized before the hearts were harvested for histological and biochemical analyses. At the age of 38 weeks, SHR ‐obese, but not SHR ‐lean, showed increased body weight and impaired glucose tolerance together with dyslipidemia compared with normotensive rats. Mean blood pressure was similarly increased in SHR ‐lean and SHR ‐obese when compared with normotensive rats (178±9 and 180±8 mm Hg [not significant] versus 118±5 mm Hg, P .01 for both), but left ventricular end‐diastolic pressure was more increased in SHR ‐obese than in SHR ‐lean. Impairment of left atrial emptying function, increase in total atrial activation time, and conduction heterogeneity, as well as prolongation of inducible atrial fibrillation durations, were more pronounced in SHR ‐obese as compared with SHR ‐lean. Histological and biochemical examinations revealed enhanced triglycerides and more pronounced fibrosis in the left atrium of SHR ‐obese. Besides increased expression of profibrotic markers in SHR ‐lean and SHR ‐obese, the profibrotic extracellular matrix protein osteopontin was highly upregulated only in SHR ‐obese. In addition to hypertension alone, concomitant obesity and metabolic syndrome add to the atrial arrhythmogenic phenotype by impaired left atrial emptying function, local conduction abnormalities, interstitial atrial fibrosis formation, and increased propensity for atrial fibrillation.
Publisher: Springer Science and Business Media LLC
Date: 23-05-2010
Publisher: Elsevier BV
Date: 06-2023
Publisher: Elsevier BV
Date: 05-2019
DOI: 10.1016/J.HRTHM.2018.11.027
Abstract: Reentrant circuits are considered to be critically dependent on a single protected slow conducting isthmus. The purpose of this study was to investigate conduction properties and electrogram (EGM) characteristics of the entire circuit in localized atrial reentrant circuits using high-resolution mapping. Fifteen localized reentrant atrial tachycardias were studied with high-resolution mapping (Rhythmia). EGMs along the entire circuit were analyzed offline for fractionation, duration, and litude. Maps were exported to MATLAB (MathWorks) to measure bipolar voltage and conduction velocities (CVs) within the circuit. Slow conduction was defined as <30 cm/s. Fifteen localized re-entrant circuits (12 left atrial, 3 right atrial) with mean cycle length 273 ± 40 ms were analyzed using high-resolution maps (22,389 ± 13,375 EGMs). A mean of 4.5 ± 1.6 slow conduction corridors were identified per circuit. Although the entire circuit was of low voltage, the bipolar voltage in slow conducting corridors was significantly lower than the rest of the circuit (0.22 ± 0.20 mV vs 0.50 ± 0.48 mV P <.001). The mean conduction velocity of the circuit, excluding slow conduction areas, was 90.3 ± 34.3 cm/s vs 13.9 ± 3.5 cm/s (P <.001) in the slow conduction corridors. EGM analysis at the slowest conduction corridors demonstrated fractionation (100%) with longer EGM duration compared to the other slow conduction corridors along the circuit (99 ± 9 ms vs 74 ± 11 ms P = .003). In contrast to current understanding, localized atrial reentrant circuits have multiple sequential "corridors" of very slow conduction (2-7) that contribute to maintenance of arrhythmia. The localized reentry occurs in low-voltage areas, with voltage further reduced in these multiple slow conducting corridors.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 04-2021
Publisher: Elsevier BV
Date: 12-2018
DOI: 10.1016/J.HRTHM.2018.07.029
Abstract: Battery longevity is an important factor that may influence the selection of cardiac implantable electronic devices (CIEDs). However, there remains a lack of industry-wide standardized reporting of predicted CIED longevity to facilitate informed decision-making for implanting physicians and payers. The purpose of this study was to compare the predicted longevity of current generation CIEDs using best-matched CIEDs settings to assess differences between brands and models. Data were extracted for current model pacemakers, implantable cardioverter-defibrillators (ICDs), and cardiac resynchronization therapy-defibrillators (CRT-Ds) from product manuals and, where absent, by communication with the manufacturers. Pacemaker longevity estimations were based on standardized pacing outputs (2.5V, 0.40-ms pulse width, 500-Ω impedance) and pacing loads of 50% or 100% at 60 bpm. ICD and CRT-D longevity were estimated at 0% pacing and 15% atrial plus 100% biventricular pacing, with essential capacitor reforms and zero clinical shocks. Mean maximum predicted longevity of single- and dual-chamber pacemakers was 12.0 ± 2.1 and 9.8 ± 1.9 years, respectively. Use of advanced features such as remote monitoring, prearrhythmia electrogram storage, and rate response can result in ∼1.4 years of reduction in longevity. Mean maximum predicted longevity of ICDs and CRT-Ds was 12.4 ± 3.0 and 8.8 ± 2.1 years, respectively. Of note, there were significant variations in predicted CIED longevity according to device manufacturers, with up to 44%, 42%, and 44% difference for pacemakers, ICDs, and CRT-Ds, respectively. Contemporary CIEDs demonstrate highly variable predicted longevity according to device manufacturers. This may impact on health care costs and long-term clinical outcomes.
Publisher: Elsevier BV
Date: 08-2020
DOI: 10.1016/J.HLC.2019.11.006
Abstract: Studies have shown that suboptimal anticoagulation quality, as measured by time in therapeutic range (TTR), affects a significant percentage of patients with atrial fibrillation (AF). However, TTR has not been previously characterised in Indigenous Australians who experience a greater burden of AF and stroke. Indigenous and non-Indigenous Australians with AF on warfarin anticoagulation therapy were identified from a large tertiary referral centre between 1999 and 2012. Time in therapeutic range was calculated as a proportion of daily international normalised ratio (INR) values between 2 and 3 for non-valvular AF and 2.5 to 3.5 for valvular AF. INR values between tests were imputed using the Rosendaal technique. Linear regression models were employed to characterise predictors of TTR. Five hundred and twelve (512) patients with AF on warfarin were included (88 Indigenous and 424 non-Indigenous). Despite younger age (51±13 vs 71±12 years, p<0.001), Indigenous Australians had greater valvular heart disease, diabetes, and alcohol excess compared to non-Indigenous Australians (p<0.05 for all). Time in therapeutic range was significantly lower in Indigenous compared to non-Indigenous Australians (40±29 vs 50±31%, p=0.006). Univariate predictors of poorer TTR included Indigenous ethnicity, younger age, diuretic use, and comorbidities, such as valvular heart disease, heart failure and chronic obstructive pulmonary disease (p<0.05 for all). Valvular heart disease remained a significant predictor of poorer TTR in multivariate analyses (p=0.004). Indigenous Australians experience particularly poor warfarin anticoagulation quality. Our data also suggest that many non-Indigenous Australians spend suboptimal time in therapeutic range. These findings reinforce the importance of monitoring warfarin anticoagulation quality to minimise stroke risk.
Publisher: Informa UK Limited
Date: 03-05-2016
DOI: 10.1080/14779072.2016.1179581
Abstract: Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia with a one in four lifetime risk in adults over the age of forty. Traditionally, AF management has focused on the three pillars of rate control, rhythm control and appropriate anticoagulation to reduce stroke risk. More recently, the importance of cardiovascular risk factor management in AF has emerged as a fourth and essential pillar with improved patient outcomes. Here, we aim to summarize the current available evidence for the association between various modifiable risk factors and AF, and to identify optimal treatment targets to improve outcomes. Expert Commentary: Care for AF patients utilizing an integrated approach and aggressive lifestyle management may reduce the enormous burden of this arrhythmia.
Publisher: Oxford University Press (OUP)
Date: 24-07-2023
Abstract: Exercise training reduces recurrence of arrhythmia and symptom severity amongst patients with symptomatic, non-permanent atrial fibrillation (AF). However, there is little evidence on whether this effect is modified by patient sex. In a sub-analysis from the ACTIVE-AF (A Lifestyle-based, PhysiCal AcTIVity IntErvention for Patients With Symptomatic Atrial Fibrillation) randomized controlled trial, we compared the effects of exercise training on AF recurrence and symptom severity between men and women. The ACTIVE-AF study randomized 120 patients (69 men, 51 women) with paroxysmal or persistent AF to receive an exercise intervention combining supervised and home-based aerobic exercise over 6 months or to continue standard medical care. Patients were followed over a 12-month period. The co-primary outcomes were recurrence of AF, off anti-arrhythmic medications and without catheter ablation, and AF symptom severity scores. By 12 months, recurrence of AF was observed in 50 (73%) men and 34 (67%) women. In an intention-to-treat analysis, there was a between-group difference in favour of the exercise group for both men [hazard ratio (HR) 0.52, 95% confidence interval (CI): 0.29–0.91, P = 0.022] and women (HR 0.47, 95% CI: 0.23–0.95, P = 0.035). At 12 months, symptom severity scores were lower in the exercise group compared with controls amongst women but not for men. An exercise-based intervention reduced arrhythmia recurrence for both men and women with symptomatic AF. Symptom severity was reduced with exercise in women at 12 months. No difference was observed in symptom severity for men. Australia and New Zealand Clinical Trials Registry: ACTRN12615000734561
Publisher: Elsevier BV
Date: 08-2016
Publisher: Elsevier BV
Date: 12-2018
DOI: 10.1016/J.JACEP.2018.08.014
Abstract: The aims of the study were to characterize: 1) electrical and electroanatomical remodeling in patients with atrial fibrillation (AF) with obesity and 2) the impact of epicardial fat depots on adjacent atrial tissue. Obesity is associated with an increased risk of AF. A total of 115 patients with AF who underwent AF ablation were screened. After exclusion, 26 patients were ided into 2 groups (obese: body mass index [BMI] ≥27 kg/m The BMIs of the obese and reference groups were 30.2 ± 2.6 and 25.2 ± 1.3 kg/m Obesity is associated with electroanatomical remodeling of the atria, with areas of low voltage, conduction slowing, and greater fractionation of electrograms. These changes were more pronounced in regions adjacent to epicardial fat depots, which suggested a role for fat depots in the development of the AF substrate.
Publisher: Elsevier BV
Date: 07-2016
DOI: 10.1016/J.ANAI.2016.04.024
Abstract: The diagnosis of allergic bronchopulmonary aspergillosis (ABPA) in asthma is often made in patients with total serum IgE levels greater than 1,000 IU/mL in conjunction with evidence of Aspergillus sensitization. The specificity of total serum IgE for the diagnosis of ABPA is low even when combined with serum Aspergillus specific IgE. To determine the prevalence of ABPA and to identify alternative clinical predictors for ABPA among asthmatic patients with a total serum IgE level greater than 1,000 IU/ml. This study was conducted in a tertiary hospital in Melbourne, Australia, with a large asthma and allergy service. Patients with asthma and total serum IgE levels greater than 1,000 IU/ml from January 1, 2005, through December 31, 2014, were included. Patients were considered to have concomitant allergic conditions if they had atopic eczema, allergic rhinitis, or both. The diagnosis of ABPA was based on the managing physician's documented diagnosis and referenced to criteria proposed by the International Society for Human and Fungal Mycology. The prevalence of ABPA in our cohort was 15.8%. Older age, elevated total serum IgE level, reduced lung function, and the absence of other concomitant allergic conditions increased the risk of ABPA. After multivariate logistic regression, patients without concomitant allergic conditions had an odds ratio of 4.4 (95% confidence interval, 1.9-10.1 P = .001) for ABPA when compared with patients with allergic conditions. The absence of atopic eczema and allergic rhinitis in these patients increases the likelihood of ABPA. Eliciting an accurate allergy history may be a useful bedside clinical tool when considering the diagnosis of ABPA.
Publisher: Elsevier BV
Date: 08-2019
DOI: 10.1016/J.HRTHM.2019.02.020
Abstract: Atrial fibrillation (AF) is common after pacemaker implantation. However, the impact of pacemaker algorithms in AF prevention is not well understood. The purpose of this study was to evaluate the role of pacing algorithms in preventing AF progression. A systematic search of articles using the PubMed and Embase databases resulted in a total of 754 references. After exclusions, 21 randomized controlled trials (8336 patients) were analyzed, comprising studies reporting ventricular pacing percentage (VP%) (AAI vs DDD, n = 1 reducing ventricular pacing [RedVP] algorithms, n = 2) and atrial pacing therapies (atrial preference pacing [APP], n = 14 atrial antitachycardia pacing [aATP]+APP, n = 3 RedVP+APP+aATP, n = 1). Low VP% (<10%) lead to a nonsignificant reduction in the progression of AF (hazard ratio [HR] 0.80 95% confidence interval [CI] 0.57-1.13 P = .21 I This meta-analysis of randomized controlled trials demonstrated that algorithms to reduce VP% can be considered safe. Low burden VP% did not significantly suppress AF progression. The atrial pacing therapy algorithms could suppress PAC burden but did not prevent AF progression.
Publisher: Wiley
Date: 03-02-2012
DOI: 10.1111/J.1540-8175.2011.01609.X
Abstract: The ratio of peak tricuspid regurgitation velocity (TRV) and right ventricular outflow time-velocity integral (TVI RVOT) has been described as a good correlate of pulmonary vascular resistance (PVR). However, this method has not been well studied in congenital heart disease. Twenty patients with post-tricuspid shunt lesions who were planned to undergo cardiac catheterization were enrolled for the study. The ratio of TRV/TVI(RVOT) was measured via transthoracic echocardiography and correlated with invasively derived PVR (PVR(CATH)). PVR(CATH) was measured by cardiac catheterization. Fick's principle was used to calculate the pulmonary blood flow and oxygen consumption was assumed. Linear regression analysis was done to find the correlation between TRV/TVI(RVOT) and PVR(CATH). There was a significant correlation between the two variables, r = 0.635(P = 0.003). Subgroup analysis revealed that this correlation was better at lower values of PVR(CATH) (r = 0.817 for PVR 6 WU). TRV/TVI(RVOT) ratio of greater than 0.145 predicted with 80% sensitivity and specificity a PVR > 6 WU. There is modest correlation between TRV/TVI(RVOT) ratio and invasively derived PVR in congenital shunt lesions, especially in PVR < 6 WU. TRV/TVI(RVOT) ratio could be useful in identifying patients with congenital shunts whose PVR is likely to be <6 WU, and hence, do not need cardiac catheterization.
Publisher: Elsevier BV
Date: 07-2015
DOI: 10.1016/J.JACC.2015.04.058
Abstract: Obesity and atrial fibrillation (AF) are public health issues with significant consequences. This study sought to delineate the development of global electrophysiological and structural substrate for AF in sustained obesity. Ten sheep fed ad libitum calorie-dense diet to induce obesity over 36 weeks were maintained in this state for another 36 weeks 10 lean sheep with carefully controlled weight served as controls. All sheep underwent electrophysiological and electroanatomic mapping hemodynamic and imaging assessment (echocardiography and dual-energy x-ray absorptiometry) and histology and molecular evaluation. Evaluation included atrial voltage, conduction velocity (CV), and refractoriness (7 sites, 2 cycle lengths), vulnerability for AF, fatty infiltration, atrial fibrosis, and atrial transforming growth factor (TGF)-β1 expression. Compared with age-matched controls, chronically obese sheep demonstrated greater total body fat (p < 0.001) LA volume (p < 0.001) LA pressure (p < 0.001), and PA pressures (p < 0.001) reduced atrial CV (LA p < 0.001) with increased conduction heterogeneity (p < 0.001) increased fractionated electrograms (p < 0.001) decreased posterior LA voltage (p < 0.001) and increased voltage heterogeneity (p 0.8) or ERP heterogeneity (p > 0.3). Obesity was associated with more episodes (p = 0.02), prolongation (p = 0.01), and greater cumulative duration (p = 0.02) of AF. Epicardial fat infiltrated the posterior LA in the obese group (p < 0.001), consistent with reduced endocardial voltage in this region. Atrial fibrosis (p = 0.03) and TGF-β1 protein (p = 0.002) were increased in the obese group. Sustained obesity results in global biatrial endocardial remodeling characterized by LA enlargement, conduction abnormalities, fractionated electrograms, increased profibrotic TGF-β1 expression, interstitial atrial fibrosis, and increased propensity for AF. Obesity was associated with reduced posterior LA endocardial voltage and infiltration of contiguous posterior LA muscle by epicardial fat, representing a unique substrate for AF.
Location: India
No related grants have been discovered for Rajiv Mahajan.