Research Articles (Cardiology)

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    The South African SHARE-TAVI registry : incidence and risk factors leading to conduction disturbances requiring permanent pacemaker implantation
    (South African Heart Association, 2021) Du Toit, Rudolf; Doubell, Anton; Abelson, Mark; Hellig, Farrel; Horak, Adie; Mabin, Thomas; Klug, Eric; Schaafsma, Elizabeth; Van Wyk, Jacques; Scherman, Jacques; Ntsekhe, Mpiko; Weich, Hellmuth
    Background: One of the most common complications post transcatheter aortic valve implantation (TAVI) is the development of heart block requiring permanent pacemaker implantation (PPM). The incidence of PPM in international registries ranges from 13% - 17.5%. Methods: The aim of this observational study was to report the PPM rate in the SHARE-TAVI registry and determine the clinical, electrocardiographic and procedural predictors of PPM as well as the effect of PPM on clinical outcomes. Results: Three hundred and fi ve subjects were analysed. The PPM rate was 9%. Third degree atrioventricular block at the time of implant was the most common indication for PPM. Self-expanding valves (PPM rate 14% vs. 6% for balloon-expandable valves, p=0.02) were correlated with the need for PPM. Baseline ECG predictors of PPM were axis deviation, QRS duration and conduction delay, most notably a pre-existing right bundle branch block (OR 15.88, p<0.01). PPM infl uenced functional class at 30 days, but not the need for repeat hospitalisation or mortality at 30-day and 1-year follow-up. Conclusions: A PPM rate lower than that reported in large international registries was found. Predictors of PPM and the infl uence of PPM on outcomes were similar to those reported in the international data.
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    The hidden continuum of HIVassociated cardiomyopathy : a focussed review with case reports
    (South African Heart Association, 2021) Robbertse, Pieter-Paul; Doubell, Anton; Nachega, Jean; Herbst, Philip
    ENGLISH ABSTRACT: HIV-associated cardiomyopathy (HIVAC) is a poorly understood group of diseases with a poor prognosis once ventricular dysfunction is present. Cardiovascular magnetic resonance has revealed a previously unappreciated burden of asymptomatic myocardial abnormalities in people living with HIV, including abnormalities already present at the time of HIV diagnosis. These abnormalities include thickened, inflamed ventricles that bear resemblance to cases of symptomatic HIVAC that are reported on in this article. Our understanding and the significance of asymptomatic HIV-associated myocardial pathology will be explored as early disease on a continuum towards more advanced cardiomyopathy. The need for prospective research in persons naïve to anti-retroviral therapy is emphasised as it may provide key findings to better understand this elusive disease process.
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    An evaluation of informed consent comprehension by adult trial participants in South Africa at the time of providing consent for clinical trial participation and a review of the literature
    (Dove Medical Press, 2019) Burgess, Lesley Jean; Gerber, Berna; Coetzee, Kathleen; Terblanche, Marli; Agar, Gareth; Kotze, Theunis J. V. W.
    Introduction: The informed consent process is a fundamental part of clinical trials and is driven by both a legal and ethical agenda. The process may be seriously compromised if trial participants sign the informed consent document without fully understanding its contents. In developing countries such as South Africa, this concern is important due to the potential vulnerability of these patients and their risk for research exploitation. Aim: To evaluate the understanding of 11 important components and concepts related to clinical research by adult trial participants in a developing country at the time of providing consent for trial participation. Methods: 46 consecutive adult patients who qualified and consented to being enrolled in ongoing cardiovascular risk clinical trials at TREAD Research in the Western Cape, South Africa, were included in this study. After giving informed consent, participants were subjected to both a close-ended (self-report) and an open-ended method (descriptive narrative) to assess their understanding of various components and concepts related to clinical research pertaining to the initial informed consent document. The descriptive narrative was recorded and then later transcribed and assessed by two independent assessors. Results: There was a marked difference between the two methodologies used to assess patient comprehension of the various components. With the exception of concepts voluntariness and right to withdraw, trial participants’ understanding of the informed consent document was poor – especially with regard to the following concepts: randomization, risks, placebo and blinding. Higher levels of comprehension were obtained for the participant self-reports and lower levels for the narrative descriptions. Conclusion: The participant comprehension at this site was poor, and the process for taking informed consent subsequently needs to be modified so as to improve informed consent comprehension.
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    An unusual complication after mitral valve repair
    (South African Heart Association, 2019) Kabwe, Lorrita; Weich, Hellmuth; Pecoraro, Alfonso
    ENGLISH ABSTRACT: A 22-year-old lady presented to the outpatient department with new onset dyspnoea and effort intolerance. She had a prior history of successful mitral valve repair 5 years previously for symptomatic severe mitral regurgitation, secondary to myxomatous mitral valve prolapse. Clinical examination revealed an undisplaced apex with a parasternal heave (suggestive of right ventricular hypertrophy) and a soft ejection systolic murmur in the pulmonary area. On review of her previous echocardiograms, the pre-surgery apical 4 chamber (Figure 1A) revealed a dilated left ventricle and atrium with normal right heart chambers. Her post-operative echocardiogram (Figure 1B) confirmed successful mitral valve repair with a reduction in left ventricular size and normal right ventricle. A review of her echocardiogram (Figure 1C) at this visit, revealed new right ventricle dilatation with features of diastolic overload. No evidence of tricuspid/pulmonary incompetence was found. Transoesophageal echocardiography (Figure 1D) confirmed a large atrial septal defect (ASD). We concluded that this was an iatrogenic ASD as a complication of mitral valve repair. The ASD was closed percutaneously with an amplatzer device (see online publication for video supplement).
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    Interventional cardiology during the COVID-19 epidemic
    (South African Heart Association, 2020) Weich, Hellmuth; Hitzeroth, Jens; Khan, Sajidah; Kettles, David; Vachiat, Ahmed; Ntsekhe, Mpiko
    ENGLISH ABSTRACT: The impact of the COVID-19 pandemic on our lives is unprecedented and major adjustments to our practices as physicians are required. Although our comments are applicable at the time of writing, the situation changes daily and the content of this article should be adjusted accordingly. Cath lab: An unambiguous cath lab protocol should be drawn up for each facility, appropriate to local circumstances. This should include standard procedures in preparation for arrival at the lab, in the performance of procedures, and, importantly, in maintaining due diligence when removing protective gear. All team members should be well trained in these procedures. Acute coronary syndromes: Standard timing for the invasive management of patients should not change during the pandemic. Due to delays often unavoidable during the pandemic, alternative strategies such as thrombolysis may be more readily available and therefore more appropriate. Drugs: The sick COVID-19 patient often represents a pro-thrombotic state and operators should ensure adequate anti-thrombotic therapy. Knowledge of interactions between cardiac drugs and investigational antiviral treatments is important. Elective procedures: Patients with chronic cardiac conditions are at high risk and may require non-urgent procedures to avert major complications. Selecting these cases requires consideration of multiple risks and benefits.