Browsing by Author "Chin, Ashley"

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    The clinical, electrocardiographic and echocardiographic features and long-term outcome of patients with Tachycardia-induced cardiomyopathy
    (2010) Chin, Ashley; Okreglicki, A M
    Tachycardia-induced cardiomyopathy (TIC) is a reversible cause of LV systolic dysfunction that can complicate any supraventricular or ventricular tachyarrhythmia. This study is the first to compare features of pure and impure TIC. We found that impure TIC may develop more quickly than pure TIC, as impure TIC patients have a shorter duration and more severe symptoms at presentation, which suggests that underlying structural heart disease is a risk factor in the pathogenesis of TIC.
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    Electrocardiographic predictors of poor outcome in acute myocardial infarction
    (2024) Shirley, Samantha Shirley; Chin, Ashley; Viljoen, Charle; Hitzeroth, Jens; Hoevelman, Julian
    Introduction: Myocardial infarction (MI) is a major cause of death worldwide. An ECG is indicated in all patients with suspected MI. The aim of this study was to evaluate electrocardiographic predictors of outcome in acute coronary syndrome (ACS). Methods: We analyzed 12-lead ECGs of 301 consecutive patients admitted to the coronary care unit (CCU) at a tertiary centre during 2016 with a diagnosis of ACS. ECGs were done on admission, and after that daily throughout the hospitalisation. Poor outcome was defined as all-cause mortality within a three-year period after the index MI. Results: This cohort of 301 patients (42.2% female) with a mean age of 57.4±11.9 years, presented with either ST-elevation myocardial infarction (STEMI, 57.5%) or non-ST elevation myocardial infarction (NSTEMI, 42.5%). Fifty-one (16.9%) patients died within three years after their index presentation. Multivariable regression analyses revealed that left atrial enlargement (LAE, odds ratio [OR] 3.91 [95% confidence interval [CI] 1.39-11.02], p=0.010) and ST depression (OR 3.64 [95% CI 1.33-9.93], p=0.012) were predictive of poor outcome, wheras sinus rhythm with normal rate was associated with a better prognosis (OR 0.33 [95% CI 0.12- 0.91] p=0.032). Patients with two or more risk factors (i.e., LAE, ST depression, sinus tachycardia) experienced higher mortality rates (p<0.001).Conclusion: Our study showed that the ECG has prognostic value in patients presenting with acute MI. ECG features that were independently associated with increased mortality within the first three years of MI (LAE, ST depression and/or sinus tachycardia) could assist with risk stratification of patients presenting with ACS.
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    Extended electrocardiographic monitoring in patients on chronic haemodialysis and after renal transplantation
    (2023) Lee-Jones, Scott; Chin, Ashley; Viljoen Charle
    Background Chronic Kidney Disease (CKD) and chronic haemodialysis are associated with cardiovascular disease. Despite the increased risk of sudden cardiac death, few studies to date have described the burden of arrhythmias in this population. The aim of this study was to determine the prevalence, type and timing of arrhythmias by means of implantable loop recorder (ILR) monitoring in patients with CKD on chronic haemodialysis. Methods In this prospective cohort study, ILR's were implanted in twenty patients with CKD on the Renal Replacement Programme at Groote Schuur Hospital in Cape Town. Clinical, electrocardiographic and echocardiographic parameters were collected. We reviewed ILR recordings obtained between August 2015 and July 2018 and analysed arrhythmic events in relation to clinical parameters and temporal relation to dialysis sessions. Results In this cohort of 17/20 patients (1 died prior to ILR download and 2 lost to follow-up), the median age was 38 years (IQR 27.5 – 45) and left ventricular ejection fraction (LVEF) 62% (48 – 73). Clinically significant arrhythmias included atrioventricular (AV) block (n=24), atrial fibrillation (n=12) and non-sustained ventricular tachycardia (n=2). Most (57.4%) arrhythmic events occurred in the long interdialytic period between dialysis sessions. One patient with high degree AV block detected by ILR received a permanent pacemaker. Arrhythmic events were less prevalent after renal transplantation (6/17 during study period). Conclusion We have demonstrated that there is potential clinical utility of ILR monitoring in this population, which have a high risk of largely asymptomatic, clinically significant arrythmias. Larger studies are required to validate our findings.
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    Performance of re-used pacemakers and implantable cardioverter defibrillators compared with new devices at Groote Schuur Hospital, Cape Town, South Africa
    (2016) Jama, Zimasa Vuyo; Mayosi, Bongani M; Chin, Ashley
    Objectives: Little is known about the performance of re - used pacemakers and implantable cardioverter defibrillators (ICDs) in Africa. We sought to compare the risk of infection and the rate of malfunction of re - used pacemakers and ICDs with new devices at Groote Schuur Hospital in Cape Town, South Africa. Methods: This was a retrospective case comparison study of performance of re - used pacemakers and ICDs in comparison with new devices at Groote Schuur hospital over a 10 year period. The outcomes were incidence of device infection, device malfunction, early battery depletion, and device removal due to infection, malfunction, or early battery depletion. Results: Data for 126 devices implanted in 126 patients between 2003 and 2013 were analysed, of which 102 (81%) were pacemakers (51 re - used and 51 new) and 24 (19%) were ICDs (12 re - used and 12 new). There was no device infection, malfunction, early battery depletion or device removal in either the re - used or new pacemaker groups ov er the median follow up of 15.1 months (interquartile range (IQR), 1.3 - 36.24 months) for re - used pacemakers and 55.8 months (IQR, 20.3 - 77.8 months) for new pacemakers. In the ICD group, no device infection occurred over a median follow up of 35.9 months (I QR, 17.0 - 70.9 months) for re - used ICDs and 45.7 months (IQR, 37.6 - 53.7 months) for new ICDs. One device delivered inappropriate shocks which resolved without intervention and no harm to the patient, this re - used ICD subsequently needed generator replacement 14 months later. In both, the pacemaker and ICD groups, there were no procedure non related infections documented for the respective follow up periods. Conclusion: No significant differences were found in performance between re - used and new pacemakers and ICDs with respect to infection rates, device malfunction, and battery life and device removal for complications. Pacemaker and ICD reusee is feasible and safe and is a viable option for patients with bradyarrhythmias and tachyarrthythmias.