ORCID Profile
0000-0001-8167-2826
Current Organisations
Flinders Medical Centre
,
Flinders University
,
Cardiac Society of Australia and New Zealand
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Publisher: Hindawi Limited
Date: 1998
DOI: 10.1155/1998/496028
Abstract: Amiodarone is used to treat life-threatening cardiac arrhythmias. Amiodarone-induced pulmonary toxicity (APT) can be difficult to diagnose. APT may result in increased mucus production and mucin expression. Thus, serum mucin-1 was evaluated as a marker for amiodarone-induced pulmonary toxicity. Concentrations of mucin-1 in peripheral blood were determined using cancer-associated serum antigen (CASA) assay in patients taking amiodarone. Eight of ten patients who developed major amiodarone toxicity had high serum CASA levels. Patients with toxicity had a significantly higher mean rank CASA concentration compared with those without major toxicity. CASA shows potential as a marker for amiodarone-induced toxicity, particularly pulmonary toxicity.
Publisher: Elsevier BV
Date: 12-1983
DOI: 10.1016/0002-9149(83)90576-3
Abstract: A prospective study was undertaken to assess the results of an aggressive ventricular stimulation protocol in 52 nonmedicated patients without a documented or suspected ventricular arrhythmia (VA). Thirty-five patients had no structural heart disease, 8 coronary artery disease, 6 hypertrophic cardiomyopathy, 2 mitral valve disease and 1 patient had congestive cardiomyopathy. The patients were 12 to 72 years old. One to 4 ventricular premature beats (twice diastolic threshold, 2 ms in duration) were given during sinus rhythm and during ventricular pacing at 100 beats/min at the right ventricular apex. End points were initiation of 6 or more beats of VA or every extrastimulus brought to its refractory period. In 31 of 52 patients (60%), a VA was initiated (nonsustained polymorphic ventricular tachycardia in 24 patients, nonsustained monomorphic ventricular tachycardia in 2 and ventricular fibrillation requiring countershock in 5). Repetitive ventricular responses (RVR) (1 to 5 beats) were initiated in 46 patients. In 15 patients only RVRs were initiated. In 6 patients RVRs or VA were not initiated. At the end of the follow-up period (mean 14 months), no patient had spontaneous VA and all were alive. This study shows that ventricular stimulation can result in initiation of VA in patients without clinical VA. Interpretation of results of programmed ventricular stimulation in patients without clinically documented VA should be made with caution.
Publisher: Wiley
Date: 06-1978
DOI: 10.1111/J.1445-5994.1978.TB04523.X
Abstract: A 38-year-old woman presented with syncopal attacks for 27 years. The electrophysiology techniques which enabled the diagnosis of both sinus node dysfunction (sick sinus syndrome) and presence of an atrionodal bypass tract (Lown-Ganong-Levine syndrome) are illustrated.
Publisher: Wiley
Date: 05-1980
DOI: 10.1111/J.1540-8159.1980.TB05235.X
Abstract: A 39-year-old man with a history of frequent paroxysmal tachycardias for 27 years was referred for electrophysiology study. His resting electrocardiogram showed left bundle branch block, which persisted during paroxysmal tachycardia. Electrophysiology study demonstrated the presence of a right-sided accessory nodo-ventricular connection. The case is of particular importance as it illustrates the diagnostic value of QRS normalization with left atrial pacing and the therapeutic use of rapid His bundle pacing to terminate the tachycardia.
Publisher: Elsevier BV
Date: 11-1985
DOI: 10.1016/0020-7101(85)90025-X
Abstract: Conduction through the atrioventricular node (AVN) is assessed during electrophysiology study by relating the output to the input generated by an atrial extrastimulus. This extrastimulus scans electrical diastole of the heart to enable output to be plotted against input. Using this technique, we compared two mathematical models of the AVN, a rectangular hyperbola and a decaying exponential, respectively. The models were compared in 40 curves from 32 patients with only one AVN transmission pathway. Standard errors of the estimate were usually (25/40 trials) less with the exponential model, suggesting this the preferred algorithm for further development.
Publisher: Wiley
Date: 30-04-2017
DOI: 10.1002/EJHF.876
Abstract: This randomized, double-blind, placebo-controlled trial assessed whether heart rate (HR) reduction with ivabradine improves cardiac function in heart failure with preserved ejection fraction (HFpEF). The prEserveD left ventricular ejectIon fraction chronic heart Failure with ivabradine studY (EDIFY) included 179 patients in New York Heart Association (NYHA) classes II and III, in sinus rhythm, with HR of ≥70 b.p.m., NT-proBNP of ≥220 pg/mL (BNP ≥80 pg/mL) and left ventricular ejection fraction of ≥45%. Ivabradine (or placebo) was titrated to 7.5 mg b.i.d. Patients were followed for 8 months on the change and assessed for three co-primary endpoints: echo-Doppler E/e' ratio, distance on the 6-min walking test (6MWT), and plasma NT-proBNP concentration. At baseline, median E/e' was 12.8 [interquartile range (IQR): 9.9-16.3], median distance on the 6MWT was 320 m (IQR: 247-375 m), and median NT-proBNP was 375 pg/mL (IQR: 253-701 pg/mL). Baseline median HR was 75 b.p.m. (IQR: 70-107 b.p.m.). A total of 171 patients (87 in the ivabradine group, 84 in the placebo group) were evaluated for treatment efficacy. After 8 months of treatment, findings showed a median change in HR of -13.0 b.p.m. (IQR: -18.0 to -6.0 b.p.m.) in the ivabradine group and -3.5 b.p.m. (IQR: -11.5 to 3.0 b.p.m.) in the placebo group [estimated between-group difference: 7.7 b.p.m. 90% confidence interval (CI) -10 to -5.4 P < 0.0001]. No evidence of improvement was found in any of the three co-primary endpoints. There was almost no change in median E/e' in either of the two groups [median change: +1.0 (IQR: -0.8 to 2.9) in the ivabradine group -0.6 (IQR: -2.2 to 1.4) in the placebo group estimated between-group difference: 1.4, 90% CI 0.3-2.5 P = 0.135]. There were no meaningful changes in the other co-primary endpoints and no apparent trends. There was no significant safety concern. In patients with HFpEF, HR reduction with ivabradine did not improve outcomes. These findings do not support the use of ivabradine in HFpEF.
Publisher: Elsevier BV
Date: 04-1984
DOI: 10.1016/0002-8703(84)90316-8
Abstract: To evaluate factors playing a role in initiation of atrioventricular (AV) nodal reentrant tachycardia utilizing anterogradely a slow and retrogradely a fast conducting AV nodal pathway, 38 patients having no accessory pathways and showing discontinuous anterograde AV nodal conduction curves during atrial stimulation were studied. Twenty-two patients (group A) underwent an electrophysiologic investigation because of recurrent paroxysmal supraventricular tachycardia (SVT) that had been electrocardiographically documented before the study. Sixteen patients (group B) underwent the study because of a history of palpitations (15 patients) or recurrent ventricular tachycardia (one patient) in none of them had SVT ever been electrocardiographically documented before the investigation. Twenty-one of the 22 patients of group A demonstrated continuous retrograde conduction curves during ventricular stimulation. In 20 tachycardia was initiated by either a single atrial premature beat (18 patients) or by two atrial premature beats. Fifteen of the 16 patients of group B had discontinuous retrograde conduction curves during ventricular stimulation, with a long refractory period of their retrograde fast pathway. Tachycardia was initiated by multiple atrial premature beats in one patient. Thirteen out of the remaining 15 patients received atropine. Thereafter tachycardia could be initiated in three patients by a single atrial premature beat, by two atrial premature beats in one patient, and by incremental atrial pacing in another patient. In the remaining eight patients tachycardia could not be initiated. Our observations indicate that the pattern of ventriculoatrial conduction found during ventricular stimulation is a marker for ease of initiation of AV nodal tachycardia in patients with discontinuous anterograde AV nodal conduction curves.
Publisher: Wiley
Date: 08-1982
DOI: 10.1111/J.1445-5994.1982.TB03810.X
Abstract: The antiarrhythmic effect of intravenous disopyramide phosphate was assessed in a multicentre open study of 141 patients admitted to coronary care units. Disopyramide was administered in a bolus dose of 2 mg/kg over 10 min with an optional second bolus of 1 mg/kg and infusion of 0.4 mg/kg hour. Atrial fibrillation was terminated in 57% of 56 patients, supraventricular tachycardia in 82% of 11 patients, ventricular tachycardia in 88% of 17 patients and premature ventricular contractions were controlled in 85% of 55 patients. Atrial flutter was terminated in only 2 of 17 patients (12%). Side effects occurred in 38% of the patients, the most frequent being those relating to anticholinergic properties of the drug (15%) or systemic hypotension (13%). Occasionally worsening of the arrhythmia (4%), QRS widening (3) or apparent hypertension (2%) were noted. It was concluded that intravenous disopyramide is an effective antiarrhythmic agent in the coronary care unit setting, but that side effects require close monitoring of dosage.
Publisher: Elsevier BV
Date: 03-1982
Publisher: Elsevier BV
Date: 07-1984
DOI: 10.1016/S0735-1097(84)80336-8
Abstract: A patient with the Wolff-Parkinson-White syndrome manifesting four types of tachycardia is described. The location and the participation during tachycardia of two different types of accessory atrioventricular pathways were documented during a programmed stimulation study. Unusual modes of initiation of tachycardias were observed, such as the initiation of an orthodromic circus movement tachycardia by an atrial premature beat that conducted in anterograde direction down the accessory pathway.
Publisher: Elsevier BV
Date: 03-1984
DOI: 10.1016/0002-8703(84)90100-5
Abstract: Regeneration of injuries occurring in the central nervous system, particularly spinal cord injuries (SCIs), is extremely difficult. The complex pathological events following a SCI often restrict regeneration of nervous tissue at the injury site and frequently lead to irreversible loss of motor and sensory function. Neural stem rogenitor cells (NSCs/NPCs) possess neuroregenerative and neuroprotective features, and transplantation of such cells into the site of damaged tissue is a promising stem cell-based therapy for SCI. However, NSC/NPCs have mostly been induced from embryonic stem cells or fetal tissue, leading to ethical concerns. The pioneering work of Yamanaka and colleagues gave rise to the technology to induce pluripotent stem cells (iPSCs) from somatic cells, overcoming these ethical issues. The advent of iPSCs technology has meant significant progress in the therapy of neurodegenerative disease and nerve tissue damage. A number of published studies have described the successful differentiation of NSCs/NPCs from iPSCs and their subsequent engraftment into SCI animal models, followed by functional recovery of injury. The aim of this present review is to summarize various iPSC- NPCs differentiation methods, SCI modelling, and the current status of possible iPSC- NPCs- based therapy of SCI.
Publisher: American Chemical Society (ACS)
Date: 10-03-2007
DOI: 10.1021/JP0673664
Abstract: The crystal and molecular structure of 1,8-thianaphthalene has been determined and compared with other single-atom peribridged naphthalenes (SAPN). The measured CSC angle is 73.06 degrees, which is the smallest bridging angle yet recorded for a SAPN derivative. The ab initio calculations using G3(MP2)//B3LYP method were performed for peribridged naphthalenes in order to determine how the strain of the four-membered ring is influenced by the type of bridge linking 1,8 positions. The electronic structure of 1,8-thia- and 1,8-sulfonenaphthalenes has been studied by UV photoelectron spectroscopy. We have tried to identify and distinguish the strain effect on the electronic structure of the naphthalene moiety.
Publisher: Massachusetts Medical Society
Date: 10-03-2011
Publisher: Medknow
Date: 2014
Abstract: Longitudinal integrated clerkships (LIC) in the first major clinical year in medical student training have been demonstrated to be at least equivalent to and in some areas superior to the "traditional block rotation" (TBR). Flinders University School of Medicine is starting a pilot changing the traditional teaching at the major Academic Medical Centre from TBR to LIC (50% of students in other locations in the medical school already have a partial or full LIC programme). This paper summarises the expected challenges presented at the "Rendez-Vous" Conference in October 2012: (a) creating urgency, (b) training to be a clinician rather than imparting knowledge, (c) resistance to change. We discuss the unexpected challenges that have evolved since then: (a) difficulty finalising the precise schedule, (b) underestimating time requirements, (c) managing the change process inclusively. Transformation of a "block rotation" to "LIC" medical student education in a tertiary academic teaching hospital has many challenges, many of which can be anticipated, but some are unexpected.
Publisher: Wiley
Date: 08-1980
DOI: 10.1111/J.1445-2197.1980.TB04143.X
Abstract: The early and late results of the first 103 patients with left main coronary obstruction submitted to bypass grafting in South Australia are presented. A satisfactory hospital mortality of 2.9% and a surprisingly low late mortality of 2.9% (at an average follow-up time of 30 months), were obtained, and these figures, when taken in conjunction with a symptomatic relief rate of 83% at 24 months, have encouraged us to continue to recommend coronary artery grafting as the treatment of choice of left main stem disease.
Publisher: Elsevier BV
Date: 03-1982
Publisher: Elsevier BV
Date: 02-2015
Publisher: Wiley
Date: 10-1980
DOI: 10.1111/J.1445-5994.1980.TB04971.X
Abstract: The normal period of depression of sinoatrial node automaticity (sinus node recovery time, SNRT) following one minute of overdrive right atrial pacing was evaluated in 34 subjects, aged 27--83 years. Specific attention was paid to the influence of the patient's heart rate, atrial pacing rate (100 and 130 bpm) and site, and of vagal and sympathetic effects, as assessed by observations following the administration of atropine, 0 . 03 mg/kg, and propranolol, 0 . 15 mg/kg. Normal SNRT was 1046 +/- 17 ms at 100 bpm and 980 +/- 19 ms at 130 bpm. Linear regression analysis showed that at pacing rates of both 100 and 130 bpm, both before and after autonomic block, a highly significant relation existed between SNRT and the stable P-P interval observed after cessation of pacing. These regression equations were used to develop a correction factor for cycle length in assessing SNRT (corrected SNRT = SNRT--0 . 86 X cycle length, where 0 . 86 was the slope of the regression equation). The mean corrected SNRT was 314 +/- 10 ms and 290 +/- 8 ms at 100 and 130 bpm, respectively. Vagal influences increased SNRT and were of greater magnitude than the decrease in SNRT due to sympathetic effects. Corrected SNRT was significantly longer following left atrial than following right atrial pacing, but in those eight patients studied, was not significantly different following right atrial or right ventricular stimulation.
Publisher: Wiley
Date: 09-1985
DOI: 10.1111/J.1540-8159.1985.TB05876.X
Abstract: The atrioventricular node (AVN) has been modeled by relating output (A2H2 or H1H2) to input (A1A2) where A and H are atrial and His bundle electrograms during fixed rate atrial pacing (A1A1) or with an extrastimulus (A2). (Formula: see text) This study examined this model in 61 nonselected patients, specifically for AVN (in)stability and the possibility of multiple pathways. After programmed atrial stimulation at two basic cycle lengths of 600 ms and 462 ms, A1H1, A2H2 and H1H2 were digitized and plotted as a function of A1A2. Seven of 104 trials were rejected as SD. A1H1 was greater than 15 ms, suggesting AVN instability. Another 26 and 34 plots, respectively, of A2H2 and H1H2 were rejected because of inadequate data. In the remainder, goodness of fit of the single exponentials was tested statistically in three ways: R2, the runs test, and the Kendall rank coefficient test. Results were compared with an electrophysiologist who examined plots for one or more pathways (either discontinuous curves or slope change in a continuous curve). Single exponentials were successfully fitted (by runs test) in 44/71 and 34/63 of A2H2 and H1H2 plots, respectively, usually in accordance with the cardiologist. Discordance between computations and the cardiologist could be attributed to data scatter and lack of a sufficiently rigid stimulation protocol. The identification of bifurcation points in the presence of multiple pathways, particularly when manifest as a change in slope (approximately 6% of trials) rather than discontinuity of plots (approximately 20% of trials) remains an outstanding problem.
Publisher: Wiley
Date: 05-1979
DOI: 10.1111/J.1540-8159.1979.TB03652.X
Abstract: A 69-year-old man presented with recurrent palpitations since childhood. Electrophysiology studies performed on two separate occasions revealed the combination of sick sinus syndrome and AV node re-entrant tachycardia. The case is reported because it illustrates marked temporal variability in the electrophysiological properties of the dual AV node pathways, and also deleterious effects of verapamil on sinoatrial node function.
Publisher: Elsevier BV
Date: 05-2003
DOI: 10.1016/S0735-1097(03)00338-3
Abstract: The Australian Intervention Randomized Control of Rate in Atrial Fibrillation Trial was a multicenter trial of atrioventricular junction ablation and pacing (AVJAP) compared with pharmacologic ventricular rate control (medication [MED]) in patients with mild to moderately symptomatic permanent atrial fibrillation (AF). There have been very few prospective randomized trials, undertaken in highly symptomatic patients, comparing AVJAP with pharmacologic methods of ventricular rate control for patients with permanent AF. There were 99 patients (70 men, mean age 68 +/- 8.6 years) at five centers. Forty-nine patients were randomized to AVJAP while 50 patients were randomized to pharmacologic control. The primary end point was cardiac function measured by echocardiography and exercise tolerance. The secondary end points were ventricular rate control, evaluated by 24-h ambulatory electrocardiographic monitoring, and quality of life. Data were collected at randomization and then at one month, six months, and 12 months post-randomization. At 12 months follow-up there was no significant difference in left ventricular ejection fraction (AVJAP: 54 +/- 17% MED: 61 +/- 13% [p = ns]) or exercise duration on treadmill testing (AVJAP: 4.1 +/- 2 min MED: 4.6 +/- 2 min [p = ns]) however, the peak ventricular rate was lower in the AVJAP group during exercise (112 +/- 17 beats/min vs. 153 +/- 36 beats/min, p < 0.05) and activities of daily life (117 +/- 16 beats/min vs. 152 +/- 37 beats/min, p < 0.05). The CAST quality-of-life questionnaire revealed that patients in the AVJAP group had fewer symptoms at six months (p = 0.003) and at 12 months (p = 0.004). The observed relative risk reduction in symptoms at 12 months was 18%. Global subjective semiquantitative measurement of quality of life using the "ladder of life" revealed that the AVJAP group reported a 6% better quality of life at six months (p = 0.011). In this trial, AVJAP for patients with mild to moderately symptomatic permanent AF did not worsen cardiac function during long-term follow-up, and quality of life was improved.
Publisher: Wiley
Date: 07-1984
DOI: 10.1111/J.1540-8159.1984.TB05604.X
Abstract: Inflammation occurs in all tissues in response to injury or stress and is the key process underlying hepatic fibrogenesis. Targeting chronic and uncontrolled inflammation is one strategy to prevent liver injury and fibrosis progression. Here, we demonstrate that triggering receptor expressed on myeloid cells 1 (TREM-1), an lifier of inflammation, promotes liver disease by intensifying hepatic inflammation and fibrosis. In the liver, TREM-1 expression was limited to liver macrophages and monocytes and was highly upregulated on Kupffer cells, circulating monocytes, and monocyte-derived macrophages in a mouse model of chronic liver injury and fibrosis induced by carbon tetrachloride (CCl4) administration. TREM-1 signaling promoted proinflammatory cytokine production and mobilization of inflammatory cells to the site of injury. Deletion of Trem1 reduced liver injury, inflammatory cell infiltration, and fibrogenesis. Reconstitution of Trem1-deficient mice with Trem1-sufficient Kupffer cells restored the recruitment of inflammatory monocytes and the severity of liver injury. Markedly increased infiltration of liver fibrotic areas with TREM-1-positive Kupffer cells and monocytes/macrophages was found in patients with hepatic fibrosis. Our data support a role of TREM-1 in liver injury and hepatic fibrogenesis and suggest that TREM-1 is a master regulator of Kupffer cell activation, which escalates chronic liver inflammatory responses, activates hepatic stellate cells, and reveals a mechanism of promotion of liver fibrosis.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 22-01-2019
Abstract: To date, limited population‐level studies have examined the impact of sex on the acute complications of cardiac implantable electronic devices ( CIED) , including permanent pacemakers, implantable cardioverter defibrillators, and cardiac resynchronization therapy devices. We studied all patients aged years from 2010 to 2015 who were a resident of Australia or New Zealand, undergoing a new permanent pacemaker, implantable cardioverter defibrillator , or cardiac resynchronization therapy implant. Standardized variables were collected including patient demographic characteristics, primary and secondary diagnoses, procedures performed and discharge status. Diagnoses and procedures were coded as per the International Classification of Diseases, Tenth Revision ( ICD‐10 ) and the Australian Classification of Health Interventions. The primary end point was the incidence of major CIED ‐related complications in‐hospital or within 90 days of discharge, with the effect of sex evaluated using multiple logistic regression. A total of 81 304 new CIED (61 658 permanent pacemakers, 12 097 implantable cardioverter defibrillators, 7574 cardiac resynchronization therapy) implants were included (38% women). Overall, 8.5% of women and 8.0% of men experienced a CIED complication ( P =0.008). Differences between women and men remained significant after adjustment for age, procedural acuity, and comorbidities (odds ratio 1.10, 95% CI: 1.04–1.16, P .001). Differences in CIED complication rates were primarily driven by excess rate of in‐hospital pleural drainage (1.2% women versus 0.6% men, P .001 adjusted odds ratio 1.86, 95% CI: 1.59–2.17, P .001) and pericardial drainage (0.3% women versus 0.1% men, P .001 adjusted odds ratio 2.17, 95% CI: 1.48–3.18, P .001). Women are at higher risk of acute CIED complications. Improvements in implant technique and technologies are required to minimize the risk of implant‐related complications in women.
Publisher: Wiley
Date: 06-1993
DOI: 10.1111/J.1540-8159.1993.TB01714.X
Abstract: Patients with atrial fibrillation or atrial flutter (AF) are candidates for radiofrequency (RF) catheter ablation of the atrioventricular (AV) node with the aim being to control heart rate. As patients with AF can have markedly impaired ventricular function, information concerning the hemodynamic effects of AV node ablation using RF current would be valuable. Fourteen consecutive patients (mean age 65 +/- 3 years) with drug-resistant AF underwent AV node catheter ablation with RF current and had permanent pacemaker implantation. The mean left ventricular ejection fraction (EF) by two-dimensional echocardiography immediately before ablation was 42 +/- 3% (range 14%-54%) and their mean exercise time was 4.4 +/- 0.4 minutes. Complete AV block was achieved in all 14 patients with 6 +/- 2 RF applications (range 1-18). There was no evidence of any acute cardiodepressant effect associated with delivery of RF current, and EF 3 days after ablation was 44 +/- 4%. By 6 weeks after ablation, the left ventricular EF was significantly improved compared to baseline (47 +/- 4% postablation vs 42 +/- 3% preablation P < 0.05), and this modest increase in EF was accompanied by an improvement in exercise time (5.4 +/- 0.4 min). In conclusion, delivery of RF current for AV node catheter ablation in patients with AF and reduced ventricular function is not associated with any acute cardiodepressant effect. On the contrary, improved control of rapid heart rate following successful AV node ablation is associated with a modest and progressive improvement in cardiac performance.
Publisher: AMPCo
Date: 11-1984
Publisher: Elsevier BV
Date: 10-2006
DOI: 10.1016/J.HLC.2006.02.005
Abstract: Mechanical prosthetic valve thrombosis (PVT) is a potentially life threatening event that occurs with an incidence of 0.2% per patient year following aortic valve replacement [Lengyel M, Fuster V, Keltal M, et al. Guidelines for management of left-sided prosthetic valve thrombosis: a role for thrombolytic therapy. J Am Coll Cardiol 1997 :1521-6]. We present the case of a middle-aged man with thrombosis of his aortic valve prosthesis mimicking an acute coronary syndrome. The patient received thrombolytic therapy with subsequent embolism of thrombotic debris to the leg.
Publisher: Wiley
Date: 12-1979
DOI: 10.1111/J.1445-5994.1979.TB04196.X
Abstract: The diagnostic and potential therapeutic value of rapid right atrial pacing in ventricular tachycardia and supraventricular tachycardia with aberrant intraventricular conduction, was examined. The effect of right atrial pacing at incremental rates beginning 10 bpm above the rate of the tachycardia was studied in five patients with ventricular tachycardia, and in four patients with supraventricular tachycardia with rate-related bundle branch block aberration, the mechanism of tachycardia having been demonstrated at electrophysiology study. Atrial pacing resulted in persistent (four) or occasional (one) normalisation of the QRS complexes to that seen in sinus rhythm in those five patients with ventricular tachycardia. The intraventricular conduction pattern persisted with atrial pacing in those patients with supraventricular tachycardia and aberrant intraventricular conduction. This confirms that atrial pacing is a useful and simple diagnostic test in wide QRS tachycardia, which does not require sophisticated electrophysiological facilities. In three of the patients with ventricular tachycardia, atrial pacing terminated the arrhythmia, suggesting potential therapeutic use of rapid atrial pacing in such patients.
Publisher: Wiley
Date: 12-1988
DOI: 10.1111/J.1445-5994.1988.TB01641.X
Abstract: Electrophysiology study was performed in 93 patients with bifascicular block and unexplained syncope. Clinical evidence of organic heart disease was present in 33 (35%). Electrophysiological abnormalities were detected in 45 patients (48%). Of these, 36 had distal conduction disease, including 28 with an HV interval greater than 55 ms (mean 76.4 ms), and eight who developed infraHisian block following either intravenous procainamide (four) or atrial pacing (four). Sick sinus syndrome was evident in six patients and a further two had carotid sinus hypersensitivity. Sustained monomorphic ventricular tachycardia (VT) was induced in only three patients, two of whom also had prolonged HV interval. Among the 93 patients, 45 had therapy which was guided by positive findings at electrophysiology study (Group 1). Of these, 42 received permanent pacemakers, two were treated with combined permanent pacing and antiarrhythmic drug therapy, and one was treated with antiarrhythmic drug alone. In addition, eight patients without electrophysiologic abnormalities were treated empirically by pacing (Group 2). Finally, 40 patients without electrophysiologic abnormalities received no specific therapy (group 3). At a mean follow-up of 39 months (range two-125 months), recurrence of syncope had occurred in 4% of Group 1 patients, and 25% of Group 3 patients (p less than 0.05). No patient in Group 2 had had recurrence. Total mortality was 40%, including 47% of patients in Group 1, 25% of Group 2, and 35% of Group 3. Death was sudden in seven patients. We concluded that among patients with bifascicular block and syncope, therapy directed by findings at electrophysiology study was associated with symptomatic improvement, but mortality was not significantly influenced.(ABSTRACT TRUNCATED AT 250 WORDS)
Publisher: Elsevier BV
Date: 03-1983
DOI: 10.1016/S0735-1097(83)80218-6
Abstract: Paroxysmal atrioventricular (AV) block was induced by exercise in an otherwise healthy young man. The only abnormalities demonstrated at comprehensive cardiac evaluation were: 1) angiographic systolic narrowing of the left anterior descending coronary artery, and 2) reversible radionuclide hypoperfusion of the septum during exercise. It is postulated that ischemia of the conduction system due to systolic milking of the left anterior descending coronary artery was responsible for the paroxysmal AV block in this patient.
Publisher: Elsevier BV
Date: 11-1989
DOI: 10.1016/0002-9149(89)90881-3
Abstract: In this prospective study, we compared outcomes after repair of humeral nonunions when morsellized fresh-frozen allograft or autograft was used to augment repair by intramedullary nailing. Sixty-five patients with humeral shaft nonunions of greater than 6 months' duration and gross instability at the nonunion site were included and treated by locked nailing, interfragmentary wiring, and bone grafting. Graft type was determined by patient preference. Outcomes assessed included union rate and functional recovery of the arm. Secondary end points included operative blood loss, operation time, hospital stay, time to fracture healing, and complications. Twenty-eight patients with autografts and 36 with allografts were followed up more than 2 years. The baseline conditions of the two groups were similar. The autograft group had greater blood loss and longer operative time than the allograft group. The autograft group also had a longer hospital stay. The healing rate, time to healing, and functional scores did not differ between these two groups. In the autograft group, 43% reported pain and limited mobility as a result of the donor site. We concluded that when used in association with locked nailing for humeral nonunions, allografts can achieve treatment results similar to autografts but without donor site complications. Level III, prognostic study. See Guidelines for Authors for a complete description of levels of evidence.
Publisher: Wiley
Date: 26-08-2016
DOI: 10.1111/MEDU.13084
Abstract: Longitudinal integrated clerkships (LICs) represent a model of the structural redesign of clinical education that is growing in the USA, Canada, Australia and South Africa. By contrast with time-limited traditional block rotations, medical students in LICs provide comprehensive care of patients and populations in continuing learning relationships over time and across disciplines and venues. The evidence base for LICs reveals transformational professional and workforce outcomes derived from a number of small institution-specific studies. This study is the first from an international collaborative formed to study the processes and outcomes of LICs across multiple institutions in different countries. It aims to establish a baseline reference typology to inform further research in this field. Data on all LIC and LIC-like programmes known to the members of the international Consortium of Longitudinal Integrated Clerkships were collected using a survey tool developed through a Delphi process and subsequently analysed. Data were collected from 54 programmes, 44 medical schools, seven countries and over 15 000 student-years of LIC-like curricula. Wide variation in programme length, student numbers, health care settings and principal supervision was found. Three distinct typological programme clusters were identified and named according to programme length and discipline coverage: Comprehensive LICs Blended LICs, and LIC-like Amalgamative Clerkships. Two major approaches emerged in terms of the sizes of communities and types of clinical supervision. These referred to programmes based in smaller communities with mainly family physicians or general practitioners as clinical supervisors, and those in more urban settings in which subspecialists were more prevalent. Three distinct LIC clusters are classified. These provide a foundational reference point for future studies on the processes and outcomes of LICs. The study also exemplifies a collaborative approach to medical education research that focuses on typology rather than on in idual programme or context.
Publisher: Wiley
Date: 02-2016
DOI: 10.1111/IMJ.12909
Abstract: Inpatient management of cardiac patients by cardiologists results in reduced mortality and hospitalisation. With increasing subspecialisation of the field because of growing management complexity and use of technological innovations, the impact of sub-specialisation on patient outcomes is unclear. To investigate whether management by subspecialty cardiologists impacts the outcomes of patients with subspecialty-specific diseases. All patients admitted to a tertiary centre over nine years with a diagnosis of heart failure, acute coronary syndrome (ACS) or primary arrhythmia were reviewed. The outcomes of these patients managed by cardiologists subspecialised in their admission diagnosis (heart failure specialists, interventionalists and electrophysiologists) were compared with those treated by general cardiologists. Heart failure was diagnosed in 1704 patients, ACS in 7763 and arrhythmia in 4398. There was no difference in length of stay (LOS) (P = 0.26), mortality (P = 0.57) or cardiovascular readmissions (P = 0.50) in heart failure patients treated by general cardiologists compared with subspecialists. In ACS patients, subspecialty management was associated with reduced LOS, cardiovascular readmissions and mortality (all P < 0.05). This reduction in mortality was seen mainly in lower risk patients (P < 0.05). There was a reduction in LOS and cardiovascular readmissions in arrhythmia patients receiving subspecialty management (both P < 0.05) but no difference in mortality (P = 0.14). ACS patients managed by interventionalists were more likely to undergo coronary intervention (P < 0.05). Electrophysiologists more frequently referred patients for catheter ablation and pacemaker implantation than general cardiologists (P < 0.05). The benefits of subspecialty care seem attributable to the appropriate selection of patients who would benefit from technological innovations in care. These results suggest that the development of healthcare systems which align cardiovascular disease with the subspecialist may be more effective.
Publisher: Elsevier BV
Date: 07-1984
DOI: 10.1016/S0735-1097(84)80337-X
Abstract: Information from programmed electrical stimulation of the heart has improved our ability to diagnose the site of origin and mechanism of a tachycardia from the 12 lead electrocardiogram. To test this hypothesis, the 12 lead electrocardiograms of a 12 year old girl with the Wolff-Parkinson-White syndrome showing four different types of tachycardia were sent for interpretation to 30 leading electrocardiologists , 22 of whom responded. A correct diagnosis of all four tachycardias was made by 13. Three or two of the tachycardias were correctly diagnosed by four and five cardiologists, respectively. The outcome of our study indicates that the pathway and mechanism of tachycardia can frequently be predicted from the 12 lead electrocardiogram alone.
Publisher: Wiley
Date: 10-1983
DOI: 10.1111/J.1445-5994.1983.TB02703.X
Abstract: Permanent pacing has usually been indicated for the treatment of organic disease of the sinus node or specific cardiac conducting tissue. We report three patients in whom profound syncope was apparently related to intense, transient autonomic dysfunction. Although ventricular standstill was documented in all three, detailed electrophysiology study, responses to graded Valsalva manoeuvres and carotid sinus massage, and repeated observations after cardiac autonomic blockade by IV atropine (0.03 mg/Kg) and propranolol (0.15 mg/Kg) were essentially normal. Permanent ventricular (VVI) pacing has controlled symptoms in all three, over follow-up period of 20 to 26 months. These observations suggest that transient autonomic imbalance may be a cause of undiagnosed cardiac syncope. This is neither excluded by normal electrophysiology study nor by normal responses to usual provocative autonomic interventions.
Publisher: Wiley
Date: 10-2020
DOI: 10.1111/IMJ.14704
Abstract: Few safety data exist comparing clinical outcomes in Australian public and private hospitals. We hypothesised that differences could exist between public and private hospitals due to differences in acuity and patient-level co-morbidities. To report comparative complications of cardiac implantable electronic device (CIED) placement in public and private hospitals. We conducted an observational cohort study of outcomes of patients aged >18 years from 2010 to 2015 undergoing a new permanent pacemaker (PPM), implantable cardioverter defibrillator (ICD) or cardiac resynchronisation therapy pacemaker or defibrillator (CRT-D/P) implant in NSW and Queensland public and private hospitals. The primary endpoint was major CIED-related complications occurring in-hospital or within 90 days of discharge. The independent effect of hospital sector was determined using multiple logistic regression, adjusting for covariates, including age, sex, co-morbidities and procedural acuity. A total of 32 364 new CIED implants (PPM 23 845, ICD 5361 and CRT-D/P 3158) were included (49% in private hospitals). Overall, 8.0% of private hospital procedures and 9.6% public hospital procedures experienced at least one complication. After adjustment, the overall risk of CIED complications was similar in private and public hospitals (OR: 0.92, 95% CI: 0.84-1.00, P = 0.06). In analysis of in idual complications, adjusted all-cause in-hospital mortality was higher in private hospitals, (OR: 1.49, 95% CI: 1.03-2.16, P = 0.036) primarily driven by an excess mortality in acute cases. The adjusted risk of in-hospital generator operation (OR: 0.53, 95% CI: 0.30-0.94, P = 0.03) and post-discharge infection (OR: 0.61, 95% CI: 0.46-0.81, P < 0.001) was lower in private hospitals. These data identify important similarities and differences in safety outcomes of CIED implantation between Australian public and private hospitals.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 09-1980
DOI: 10.1097/00005344-198009000-00001
Abstract: We examined by electrophysiologic study and clinical follow-up the use of verapamil as a prophylactic agent in 13 patients with refractory paroxysmal supraventricular tachycardia due to atrioventricular (AV) node reentry. Electrophysiologic variables and initiation and maintenance of AV nodal reentry were studied by programmed electrical stimulation. Observations were made before and after intravenous administration of verapamil, 0.15 mg/kg. Twelve of the 13 patients had previously not been controlled by other antiarrhythmic agents. Before verapamil, AV nodal reentry was induced in all 13 patients. Verapamil increased AV nodal transmission time (AH interval), as well as the effective and functional refractory periods of the AV node. Reentry could not be initiated in 5 of the 13 patients after verapamil and was nonsustained in a further 3. The echo zone for atrial premature beats which initiated tachycardia decreased in 2 of the remaining 5 patients. The rate of tachycardia was also significantly decreased. Over a mean follow-up period of 16 months, 11 of the 13 patients had definite symptomatic improvement, with decrease in frequency, duration, and/or associated symptoms of their arrhythmia. Only 1 patient had side effects which necessitated withdrawal of the drug. It was concluded that verapamil is a useful agent in the management of such patients.
Publisher: Elsevier BV
Date: 1985
DOI: 10.1016/0020-7101(85)90041-8
Abstract: The calculations of parameters of the sino-atrial node function have previously required the application of a non-linear least squares curve-fitting algorithm. We have compared five algorithms, three of which eliminate the need for direct non-linear least squares routines. The fast algorithms can provide greater accuracy while using less than 10% of the computing time. They make it feasible to provide real-time analysis during clinical electrophysiological studies.
Location: No location found
Location: Australia
No related grants have been discovered for WILLIAM HEDDLE.