Clinical and cardiovascular magnetic resonance profile of cardiomyopathy patients from South Africa: Pilot of the IMHOTEP study.

BACKGROUND: Cardiomyopathy is an important cause of heart failure, however, there is notable lack of data on causes and manifestations of cardiomyopathy in Africa. AIMS: The African Cardiomyopathy and Myocarditis Registry Program (IMHOTEP) aims to address the knowledge gap on etiology, treatment, and outcomes of cardiomyopathy in sub-Saharan Africa. METHODS AND RESULTS: We conducted a single-center pilot study to delineate the clinical and cardiovascular magnetic resonance (CMR) phenotypes of cardiomyopathy in South African patients. Assessment of the first 99 adult incident cases [mean age 36.8 ± 12.5 years; females 53.5%] enrolled in IMHOTEP showed that dilated cardiomyopathy (n = 77) was commonest, followed by hypertrophic (n = 13), restrictive (n = 5) and arrhythmogenic (n = 4) cardiomyopathies. A broad range of etiologies were encountered with secondary causes identified in 42% of patients. Onset of symptoms in the peripartum period was observed in 47% of women, and peripartum cardiomyopathy was diagnosed in 32.1% of women recruited. In addition to electrocardiography and echocardiography, CMR was performed in 67 cases and contributed diagnostically in a third of cases. Acute inflammation was rarely observed [2%] on CMR, however, late gadolinium enhancement (LGE) was noted in 92% of cases. CONCLUSION: We report a diverse spectrum of causes of cardiomyopathy in the South African population, with secondary, potentially treatable, etiologies in a significant proportion of cases. CMR was useful in delineating specific phenotypes and etiologies, influencing clinical care. A higher-than-expected burden of LGE was observed in this young patient cohort - the implications of which are yet to be determined.

Remote ischaemic conditioning: defining critical criteria for success-report from the 11th Hatter Cardiovascular Workshop.

The Hatter Cardiovascular Institute biennial workshop, originally scheduled for April 2020 but postponed for 2 years due to the Covid pandemic, was organised to debate and discuss the future of Remote Ischaemic Conditioning (RIC). This evolved from the large multicentre CONDI-2-ERIC-PPCI outcome study which demonstrated no additional benefit when using RIC in the setting of ST-elevation myocardial infarction (STEMI). The workshop discussed how conditioning has led to a significant and fundamental understanding of the mechanisms preventing cell death following ischaemia and reperfusion, and the key target cyto-protective pathways recruited by protective interventions, such as RIC. However, the obvious need to translate this protection to the clinical setting has not materialised largely due to the disconnect between preclinical and clinical studies. Discussion points included how to adapt preclinical animal studies to mirror the patient presenting with an acute myocardial infarction, as well as how to refine patient selection in clinical studies to account for co-morbidities and ongoing therapy. These latter scenarios can modify cytoprotective signalling and need to be taken into account to allow for a more robust outcome when powered appropriately. The workshop also discussed the potential for RIC in other disease settings including ischaemic stroke, cardio-oncology and COVID-19. The workshop, therefore, put forward specific classifications which could help identify so-called responders vs. non-responders in both the preclinical and clinical settings.

Profile, presentation and outcomes of prosthetic valve endocarditis in a South African tertiary hospital: Insights from the Groote Schuur Hospital Infective Endocarditis Registry.

BACKGROUND: Prosthetic valve infective endocarditis (PVE) is associated with high morbidity and mortality. The prevalence of PVE in South African retrospective studies ranges between 13% and 17%. OBJECTIVES: To define the clinical profile and outcomes of patients with PVE, and compare them with those of native valve endocarditis (NVE) patients. METHODS: We performed a prospective observational study of patients presenting or referred to Groote Schuur Hospital, Cape Town, with definite or possible infective endocarditis (IE) based on the 2015 European Society of Cardiology IE diagnostic criteria. Consenting adult patients who met the inclusion criteria were enrolled into the Groote Schuur Hospital Infective Endocarditis Registry, which was approved by the University of Cape Town Human Research Ethics Committee. This study is an analysis of the patients enrolled between 1 January 2017 and 31 December 2019. RESULTS: During the study period, a total of 135 patients received a diagnosis of possible or definite IE (PVE n=18, NVE n=117). PVE therefore accounted for 13.3% of the overall IE cohort. PVE patients had a mean (standard deviation) age of 39.1 (14.6) years, and 56.6% were male. PVE occurred within 1 year of valve surgery in 50.0% of cases. Duke's modified diagnostic criteria for definite IE were met in 94.4% of the PVE cohort. Isolated aortic valve PVE was present in 33.3%, and a combination of aortic and mitral valve PVE in 66.6%. Tissue prosthetic valves were affected in 61.1% of cases. Of the PVE cases, 55.6% were healthcare associated. On transthoracic echocardiography, vegetations (61.1%), prosthetic valve regurgitation (44.4%) and abscesses (22.2%) were discovered. Staphylococcus and Streptococcus species accounted for 38.8% and 22.2% of PVE cases, respectively, and 27.8% of cases were blood culture negative. Valve surgery was performed in 38.7% of the PVE patients, and 55.6% of the patients died during the index hospitalisation. Secondary analysis indicated that the PVE patients were sicker than those with NVE, with a higher frequency of septic shock and atrioventricular block (22.2% v. 7%; p=0.02 and 27.8% v. 12%; p=0.04, respectively). In addition, in-hospital mortality was higher in PVE patients than NVE patients (55.6% v. 31.6%; p=0.04). CONCLUSIONS: PVE was uncommon, mainly affecting tissue prosthetic valves and prosthetic valves in the aortic position. Patients with PVE were sicker than those with NVE and had high in-hospital mortality.

International normalised ratio control in a non-metropolitan setting in Western Cape Province, South Africa.

BACKGROUND: The quality of international normalised ratio (INR) control determines the effectiveness and safety of warfarin therapy. Data on INR control in non-metropolitan settings of South Africa (SA) are sparse. OBJECTIVES: To examine the time in therapeutic range (TTR) and its potential predictors in a sample of Garden Route District Municipality primary healthcare clinics (PHCs). METHODS: INR records from eight PHCs were reviewed. The TTR and percentage of patients with a TTR >65% were determined. A host of variables were analysed for association with TTR. RESULTS: The median (interquartile range (IQR)) age of the cohort (N=191) was 56 (44 - 69) years. The median (IQR) TTR was 37.2% (20.2 - 58.8); only 17.8% of patients had a TTR ≥65%. Compared with patients aged >50 years, those aged <50 had worse INR control (median (IQR) TTR 26.6% (16.1 - 53.0) v. 43.5% (23.5 - 60.1); p=0.01). Patients hospitalised for any reason during the study period had worse INR control than patients not hospitalised (median (IQR) TTR 26.2% (16.2 - 50.2) v. 42.9% (23.5 - 62.0); p=0.02). On multivariable regression analysis, participants on warfarin for atrial fibrillation/flutter had better INR control than those with other indications for warfarin (odds ratio 2.21; 95% confidence interval 1.02 - 4.77; p=0.04), but the control was still very poor. CONCLUSIONS: INR control, as determined by TTR and proportion of TTR ≥65%, in these non-metropolitan clinics was poor. Age and hospitalisation as a marker of illness predicted poor control. There was a difference in control between groups, depending on the indication for warfarin. Evidence-based measures to improve the quality of INR control in patients on warfarin therapy need to be instituted as a matter of urgency.

Prognostic value of NT-proBNP for myocardial recovery in peripartum cardiomyopathy (PPCM).

INTRODUCTION: Peripartum cardiomyopathy (PPCM) is an important cause of pregnancy-associated heart failure worldwide. Although a significant number of women recover their left ventricular (LV) function within 12 months, some remain with persistently reduced systolic function. METHODS: Knowledge gaps exist on predictors of myocardial recovery in PPCM. N-terminal pro-brain natriuretic peptide (NT-proBNP) is the only clinically established biomarker with diagnostic value in PPCM. We aimed to establish whether NT-proBNP could serve as a predictor of LV recovery in PPCM, as measured by LV end-diastolic volume (LVEDD) and LV ejection fraction (LVEF). RESULTS: This study of 35 women with PPCM (mean age 30.0 ± 5.9 years) had a median NT-proBNP of 834.7 pg/ml (IQR 571.2-1840.5) at baseline. Within the first year of follow-up, 51.4% of the cohort recovered their LV dimensions (LVEDD < 55 mm) and systolic function (LVEF > 50%). Women without LV recovery presented with higher NT-proBNP at baseline. Multivariable regression analyses demonstrated that NT-proBNP of ≥ 900 pg/ml at the time of diagnosis was predictive of failure to recover LVEDD (OR 0.22, 95% CI 0.05-0.95, P = 0.043) or LVEF (OR 0.20 [95% CI 0.04-0.89], p = 0.035) at follow-up. CONCLUSIONS: We have demonstrated that NT-proBNP has a prognostic value in predicting LV recovery of patients with PPCM. Patients with NT-proBNP of ≥ 900 pg/ml were less likely to show any improvement in LVEF or LVEDD. Our findings have implications for clinical practice as patients with higher NT-proBNP might require more aggressive therapy and more intensive follow-up. Point-of-care NT-proBNP for diagnosis and risk stratification warrants further investigation.

Myocardial Fibrosis Among Antiretroviral Therapy-Treated Persons With Human Immunodeficiency Virus in South Africa.

BACKGROUND: Heart failure is a prominent cardiovascular disease (CVD) manifestation in sub-Sarahan Africa. Myocardial fibrosis is a central feature of heart failure that we aimed to characterize among persons with human immunodeficiency virus (PWH) in South Africa. METHODS: Cardiovascular magnetic resonance (CMR) imaging was performed among PWH with viral suppression and uninfected controls, both free of known CVD. Plasma levels of N-terminal pro B-type natriuretic peptide (NT-proBNP) were measured. Comparisons by human immunodeficiency virus (HIV) status were made using linear and logistic regression, adjusted for age, sex, and hypertension. RESULTS: One hundred thirty-four PWH and 95 uninfected persons completed CMR imaging; age was 50 and 49 years, with 63% and 67% female, respectively. Compared with controls, PWH had greater myocardial fibrosis by extracellular volume fraction ([ECV] absolute difference, 1.2%; 95% confidence interval [CI], 0.1-2.3). In subgroup analyses, the effect of HIV status on ECV was more prominent among women. Women (vs controls) were also more likely to have elevated NT-proBNP levels (>125 pg/mL; odds ratio, 2.4; 95% CI, 1.0-6.0). Among all PWH, an elevated NT-proBNP level was associated with higher ECV (3.4% higher; 95% CI, 1.3-5.5). CONCLUSIONS: Human immunodeficiency virus disease may contribute to myocardial fibrosis, with an effect more prominent among women. Research is needed to understand heart failure risk among PWH within sub-Saharan Africa.

COVID-19: Cardiovascular care in sub-Saharan Africa during the COVID-19 crisis: lessons from the global experience

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The changing landscape of infective endocarditis in South Africa.

BACKGROUND: Little is known about the current clinical profile and outcomes of patients with infective endocarditis (IE) in South Africa (SA). OBJECTIVES: To provide a contemporary and descriptive overview of IE in a representative SA tertiary centre. METHODS: We conducted a retrospective review of the records of patients admitted to Groote Schuur Hospital, Cape Town, between 2009 and 2016 fulfilling universal criteria for definite or possible IE, in search of demographic, clinical, microbiological, echocardiographic, treatment and outcome information. RESULTS: A total of 105 patients fulfilled the modified Duke criteria for IE. The median age of the cohort was 39 years (interquartile range (IQR) 29 - 51), with a male preponderance (61.9%). The majority of the patients (72.4%) had left-sided native valve endocarditis, 14.3% had right-sided disease, and 13.3% had prosthetic valve endocarditis. A third of the cohort had rheumatic heart disease. Although 41.1% of patients with left-sided disease had negative blood cultures, the three most common organisms cultured in this subgroup were Staphylococcus aureus (18.9%), Streptococcus spp. (16.7%) and Enterococcus spp. (6.7%). Participants with right-sided endocarditis were younger (29 years, IQR 27 - 37) and were mainly intravenous drug users (73.3%), and the majority cultured positive for S. aureus (73.3%) with frequent septic pulmonary complications (40.0%). The overall in-hospital mortality was 16.2%, with no deaths in the group with right-sided endocarditis. Predictors of death in our patients were heart failure (odds ratio (OR) 8.16, 95% confidence interval (CI) 1.77 - 37.70; p=0.007) and age >45 years (OR 4.73, 95% CI 1.11 - 20.14; p=0.036). Valve surgery was associated with a reduction in mortality (OR 0.09, 95% CI 0.02 - 0.43; p=0.001). CONCLUSIONS: IE remains an important clinical problem in a typical teaching tertiary care centre in SA. In this setting, it continues to affect mainly young people with post-inflammatory valve disease and congenital heart disease. The in-hospital mortality associated with IE remains high. Intravenous drug-associated endocarditis caused by S. aureus is an important IE subset, comprising ~10% of all cases, which was not reported 15 years ago, and culture-negative endocarditis remains highly prevalent. Heart failure in IE carries a significant risk of death and needs a more intensive level of care in hospital. Finally, cardiac surgery was associated with reduced mortality, with the largest impact in patients with heart failure.

Recurrent idiopathic spontaneous coronary artery dissection.

Spontaneous coronary artery dissection (SCAD) is a relatively rare cause of acute coronary syndrome and sudden cardiac death, which frequently affect young women in the absence of established cardiovascular risk factors. Advancements in cardiovascular imaging account for the increasing recognition of this diagnosis and associated diagnoses, although classic diagnostic modalities such as electrocardiography remain of paramount importance. We present a young woman with recurrent SCAD and briefly discuss her management and its outcome.

The prognostic significance of the 12-lead ECG in peripartum cardiomyopathy.

BACKGROUND: Peripartum cardiomyopathy (PPCM) is an important cause of pregnancy-associated heart failure, which appears in previously healthy women towards the end of pregnancy or within five months following delivery. Although the ECG is widely used in clinical practice, its prognostic value has not been established in PPCM. METHODS: We analysed 12-lead ECGs of patients with PPCM, taken at index presentation and follow-up visits at 6 and 12 months. Poor outcome was determined by the composite endpoint of death, readmission, NYHA functional class III/IV or left ventricular ejection fraction (LVEF) of ≤35% at follow-up. RESULTS: This cohort of 66 patients had a median age of 28.59 (IQR 25.43-32.19). The median LVEF at presentation (33%, IQR 25-40) improved significantly at follow-up (LVEF 49%, IQR 38-55, P < 0.001 at 6 months; 52% IQR 38-57, P = 0.001 at 12 months). Poor outcome occurred in 27.91% at 6 months and 41.18% at 1 year. Whereas sinus tachycardia at baseline was an independent predictor of poor outcome at 12 months (OR 6.56, 95% CI 1.17-20.41, P = 0.030), sinus arrhythmia was associated with event free survival (log rank P = 0.013). T wave inversion was associated with an LVEF ≤35% at presentation (P = 0.038), but did not predict poor outcome. A prolonged QTc interval at presentation (found in almost half of the cohort) was an independent predictor of poor outcome at 6 months (OR 6.34, 95% CI 1.06-37.80, P = 0.043). CONCLUSION(S): A prolonged QTc and sinus tachycardia at baseline were independent predictors of poor outcome in PPCM at 6 months and 1 year respectively.

The changing landscape of infective endocarditis in South Africa

Background. Little is known about the current clinical profile and outcomes of patients with infective endocarditis (IE) in South Africa (SA). Objectives. To provide a contemporary and descriptive overview of IE in a representative SA tertiary centre. Methods. We conducted a retrospective review of the records of patients admitted to Groote Schuur Hospital, Cape Town, between 2009 and 2016 fulfilling universal criteria for definite or possible IE, in search of demographic, clinical, microbiological, echocardiographic, treatment and outcome information. Results. A total of 105 patients fulfilled the modified Duke criteria for IE. The median age of the cohort was 39 years (interquartile range (IQR) 29 - 51), with a male preponderance (61.9%). The majority of the patients (72.4%) had left-sided native valve endocarditis, 14.3% had right-sided disease, and 13.3% had prosthetic valve endocarditis. A third of the cohort had rheumatic heart disease. Although 41.1% of patients with left-sided disease had negative blood cultures, the three most common organisms cultured in this subgroup were Staphylococcus aureus (18.9%), Streptococcus spp. (16.7%) and Enterococcus spp. (6.7%). Participants with right-sided endocarditis were younger (29 years, IQR 27 - 37) and were mainly intravenous drug users (73.3%), and the majority cultured positive for S. aureus (73.3%) with frequent septic pulmonary complications (40.0%). The overall in-hospital mortality was 16.2%, with no deaths in the group with right-sided endocarditis. Predictors of death in our patients were heart failure (odds ratio (OR) 8.16, 95% confidence interval (CI) 1.77 - 37.70; p=0.007) and age >45 years (OR 4.73, 95% CI 1.11 - 20.14; p=0.036). Valve surgery was associated with a reduction in mortality (OR 0.09, 95% CI 0.02 - 0.43; p=0.001). Conclusions. IE remains an important clinical problem in a typical teaching tertiary care centre in SA. In this setting, it continues to affect mainly young people with post-inflammatory valve disease and congenital heart disease. The in-hospital mortality associated with IE remains high. Intravenous drug-associated endocarditis caused by S. aureus is an important IE subset, comprising ~10% of all cases, which was not reported 15 years ago, and culture-negative endocarditis remains highly prevalent. Heart failure in IE carries a significant risk of death and needs a more intensive level of care in hospital. Finally, cardiac surgery was associated with reduced mortality, with the largest impact in patients with heart failure

Approach to chest pain and acute myocardial infarction.

Patient history, physical examination, 12-lead electrocardiogram (ECG) and cardiac biomarkers are key components of an effective chest pain assessment. The first priority is excluding serious chest pain syndromes, namely acute coronary syndromes (ACSs), aortic dissection, pulmonary embolism, cardiac tamponade and tension pneumothorax. On history, the mnemonic SOCRATES (Site Onset Character Radiation Association Time Exacerbating/relieving factor and Severity) helps differentiate cardiac from non-cardiac pain. On examination, evaluation of vital signs, evidence of murmurs, rubs, heart failure, tension pneumothoraces and chest infections are important. A 12-lead ECG should be interpreted within 10 minutes of first medical contact, specifically to identify ST elevation myocardial infarction (STEMI). High-sensitivity troponins improve the rapid rule-out of myocardial infarction (MI) and confirmation of non-ST elevation MI (NSTEMI). ACS (STEMI and NSTEMI/unstable anginapectoris (UAP)) result from acute destabilisation of coronary atheroma with resultant complete (STEMI) or subtotal (NSTEMI/UAP) thrombotic coronary occlusion. The management of STEMI patients includes providing urgent reperfusion: primary percutaneous coronary intervention(PPCI) if available, deliverable within 60 - 120 minutes, and fibrinolysis if PPCI is not available. Essential adjunctive therapies include antiplatelet therapy (aspirin, P2Y12 inhibitors), anticoagulation (heparin or low-molecular-weight heparin) and cardiac monitoring.

Management of pulmonary hypertension.

Pulmonary arterial hypertension (PAH) is a potentially lethal disease mainly affecting young females. Although the precise mechanism of PAH is unknown, the past decade has seen the advent of many new classes of drugs with improvement in the overall prognosis of the disease. Unfortunately the therapeutic options for PAH in South Africa are severely limited. The Working Group on PAH is a joint effort by the South African Heart Association and the South African Thoracic Society tasked with improving the recognition and management of patients with PAH. This article provides a brief summary of the disease and the recommendations of the first meeting of the Working Group.

A lady with a broken heart: Apical ballooning syndrome.

Severe chest pain afteran emotional argumentresulted in the admissionof a healthy 72-year-oldwoman. She was haemodynamicallycompromised, with anelectrocardiogram (ECG) demonstratinganterior ST-depression and T-wave inversions(Fig. 1). Her 6-hour troponin T levelwas 132 ng/L. Cardiac catheterisationrevealed unobstructed coronary arteriesand a reduced left ventricular ejectionfraction (LVEF) of <35%, with basalhyperkinesia and apical segment ballooning(Figs 2 - 5). She was discharged home after3 days of supportive therapy. At 3 monthsshe was asymptomatic, with an equilibriumradionuclide angiography scan revealing anormal heart with an LVEF of 73%.

Resolution of nodular myocardial tuberculosis demonstrated by contrast-enhanced magnetic resonance imaging.

In sub-Saharan Africa, pericardial tuberculosis is frequently diagnosed in HIV sero-positive patients. Myocardial involvement has only rarely been reported. We present an HIV sero-positive patient in whom both pericardial and myocardial tuberculosis were diagnosed, and highlight the value of cardiac magnetic resonance imaging in the diagnosis and management of this condition.

Tuberculous effusive-constrictive pericarditis.

Infection with Mycobacterium tuberculosis and the human immunodeficiency virus has reached epidemic proportions in South Africa. Cardiac involvement occurs in approximately one per cent of patients suffering from active tuberculosis. This concerns predominantly pericardial involvement, resulting in chronic pericardial effusions, cardiac tamponade and constrictive pericarditis. Effusive-constrictive pericarditis is a clinical haemodynamic syndrome in which constriction by the visceral pericardium occurs in the presence of a tense effusion in a free pericardial space. We present a patient who was diagnosed with this condition, and highlight the value of contrast-enhanced magnetic resonance imaging in demonstrating the underlying structural and functional abnormalities.