Anton Doubell

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Image in cardiology : haemodynamics in a nutshell : constrictive pericarditis

SA Heart, 2011

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The hidden continuum of HIVassociated cardiomyopathy: A focussed review with case reports

SA heart, Oct 1, 2021

treatment (ART) has made HIVAC less common and improved outcomes, HIV infection remains a major r... more treatment (ART) has made HIVAC less common and improved outcomes, HIV infection remains a major risk factor for cardiac dysfunction. There is currently no universally accepted terminology for HIVAC. HIVAC is a collective term used to describe a number of cardiomyopathic findings that may not have a clear cause. It is helpful to broadly categorise HIVAC into 3 groups: i) Myocarditis; ii) Asymptomatic diastolic or systolic ventricular dysfunction; and iii) Symptomatic dilated cardiomyopathy with reduced systolic function. Treatment is challenging due to the poorly understood pathophysiology and the lack of clinical trials to provide evidence for the tailored management of these patients. It is unclear if current guideline directed medical therapy is the best option to optimise long term outcomes. Furthermore, it remains unknown which treatments supplementing ART are required to adequately prevent and treat HIVAC. This narrative review will highlight similarities between symptomatic and asymptomatic HIV associated myocardial pathology as observed with cardiovascular magnetic resonance (CMR). Our understanding and the significance of myocardial pathology in asymptomatic PLWH will be explored as early disease on a continuum towards more advanced disease. Furthermore,

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Developing a new electrophysiology service and training platform - narrowing the gap

The Egyptian Heart Journal, Jun 26, 2020

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AB0606 Lupus Myocarditis in the Western Cape, South Africa: Analysis of Clinical and Echocardiographic Features: Table 1

Annals of the Rheumatic Diseases, Jun 1, 2015

Background Lupus myocarditis (LM) is a serious manifestation of systemic lupus erythematosus (SLE... more Background Lupus myocarditis (LM) is a serious manifestation of systemic lupus erythematosus (SLE). LM in patients of African American ethnicity has an increased prevalence and higher mortality compared to other ethnic groups. In the mixed racial population of the Western Cape, South Africa, no data exists on the clinical features and outcome of LM. Echocardiography is frequently used to support the diagnosis of LM. Speckle tracking (ST) is more sensitive than standard imaging in the detection of left ventricular (LV) dysfunction. Literature on the use of ST in patients with clinically evident LM is limited. Objectives To give a comprehensive description of the clinical and echocardiographic features of acute LM in a mixed racial population. Methods Clinical records (over 6 years) of adult SLE patients at a tertiary referral centre were retrospectively screened for a clinical and echocardiographic diagnosis of LM. Clinical features, laboratory results, management and outcome were described. Echocardiographic images stored in a digital archive were reanalysed (where views allowed), including LV regional wall motion abnormalities (RWMA) and longitudinal strain through ST. Results 28 patients (6.1%) met inclusion criteria: 92.9% were female and 89% were of mixed racial origin. 54% of patients presented with LM within 3 months after being diagnosed with SLE. Median SLE disease activity index was 17.5 (IQR:12.3-24) and 50% of patients had concomitant lupus nephritis. Laboratory results included: low complement (92.3%); urinary protein >0.5g/day (83%); increased aRNP (62%). Initial (at time of diagnosis) and most recent echocardiographic data are summarised in table 1. Treatment included corticosteroids (96%) and cyclophosphamide (75%); 14% of patients required additional immunosuppression. Clinical improvement occurred in 67% of patients (563 days, median); 2 patients relapsed. Though the median LV ejection fraction (LVEF) improved from 35 to 47%, reduced longitudinal strain and RWMA persisted in most patients (Table 1). Overall mortality was high (12/28): 5/28 (17.9%) died due to LM compared to 2/24 (8.3%) in another case series. Mortality due to LM and/or treatment related complications were 35.7% (10/28).Table 1 Initial echocardiogram (n=28) Most recent echocardiogram (n=19) Median Ratio of test done Median Ratio of test done (IQR) (%) (IQR) (%) Time (days) 0 390 (93–799) Increased LVIDa (cm) 5.2 (4.4–5.6) 11/28 (39) 4.8 (4–5.6) 5/19 (26) LVEFb 35% (26–46) 47% (37–50) RWMA present 24/24 (100) 16/18 (89) Decreased longitudinal strain 13/13 (100) 8/8 (100) IQR: interquartile range; LVID: left ventricular internal diameter; LVEF: left ventricular ejection fraction; RWMA: regional wall motion abnormalities.a Increased LVID >5.3cm;b LVEF: Mild impairment: 45–54%; moderate: 36–44%; severe: ≤35%. Conclusions This is the largest reported case series on LM. The mixed racial population had a similar prevalence, but higher mortality compared to other ethnic groups (published literature). An increased awareness towards an early diagnosis is essential, especially in recently diagnosed SLE patients with concomitant lupus nephritis. ST (not previously described in acute LM) and RWMA showed persistent LV dysfunction despite an improved LVEF and could be utilised as a sensitive diagnostic tool in LM. Disclosure of Interest None declared

A retrospective audit of young adults who received permanent pacemakers at a teaching hospital in the Western Cape, South Africa

Frontiers in Cardiovascular Medicine

IntroductionWhile most pacemaker implantations occur in older individuals, younger patients also ... more IntroductionWhile most pacemaker implantations occur in older individuals, younger patients also receive pacemakers. In these, degenerative conduction system disease is less likely to be the cause of atrioventricular block (AVB), with other diseases being more common. There is, however, a paucity of data on this group as well as on younger pacemaker recipients that have undergone pacemaker implantation for reasons other than AVB. The aim of this study was to perform an audit of young adult permanent pacemaker recipients.MethodThis was a retrospective record review, conducted in the Division of Cardiology at Tygerberg Hospital, Cape Town, South Africa. We included 169 adult patients between the ages of 18 and 60, who received permanent pacemakers between 2010 and 2020. A subgroup analysis of patients 55 years and younger was also performed.ResultsThird degree AVB was the most common indication for pacemaker implantation (n = 115; 68%), followed by high degree AVB (n = 23; 13.6%) and ...

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Right ventricle dilatation: the big five

Heart, Feb 25, 2020

A 38-year-old man, previously well, presents after being mauled by a Cape buffalo, while on Safar... more A 38-year-old man, previously well, presents after being mauled by a Cape buffalo, while on Safari in South Africa. He recovered well but visited a cardiologist for infrequent palpitations lasting less than 10 min. A chest radiograph demonstrated increased cardiothoracic ratio raising the concern of possible traumatic mediastinal injury. His clinical examination was unremarkable. ECG demonstrated sinus rhythm with incomplete right bundle branch block. Echocardiography revealed a dilated, hyperdynamic right ventricle (RV) and dilated coronary sinus (CS). The left ventricle (LV) and aorta were normal with no evidence of aneurysm or dissection. An agitated saline bubble study was performed via the left antecubital fossa. Interestingly, all bubbles entered the right atrium (RA) via the superior vena cava (SVC) with no bubbles entering via the CS and no bubbles shunting to the left …

Constrictive pericarditis: Haemodynamics in a nutshell

The Egyptian Heart Journal, 2011

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The contemporary study of acute myocarditis in South Africa – CAMISA

European Heart Journal, Oct 1, 2021

The aetiology and estimated incidence of acute myocarditis (AM) remains undefined in Africa. Whil... more The aetiology and estimated incidence of acute myocarditis (AM) remains undefined in Africa. Whilst cardiac magnetic resonance (CMR) provides for a provisional non-invasive diagnosis, endomyocardial biopsy (EMB), which is infrequently clinically sought, remains the gold standard. The developed world has experienced a shift in the viral epidemiology of AM and the ESC's most recent position statement on myocarditis recommends both CMR and EMB as the standard of care in suspected cases. We report on the interim results of the study. To determine the nature of presentation, underlying aetiology, and outcomes of patients presenting with AM to a single tertiary centre in South Africa. A cohort of patients from a single tertiary centre in South Africa will be recruited from January 2018 to December 2022. All patients presenting or referred to the centre with clinically suspected AM that are investigated according to the ESC recommendations on myocarditis, which includes blood tests (CRP, hsTNT, HIV and Hepatitis C serology, ANA), a standard twelve-lead ECG, TTE, coronary angiography, CMR and EMB, will be included. Enrolment is ongoing. A total of 102 (mean age 42.2±13 years, 64.7% male) cases of clinically suspected AM were identified between January 2018 and January 2021. AM was confirmed in 41 (40.2%) cases on CMR only, while 41 (40.2%) were also confirmed on EMB. 4 cases of sarcoidosis, 1 case each of eosinophilic myocarditis, amyloidosis and primary cardiac lymphoma were diagnosed. Viral genome was isolated by PCR in 60 (59.8%) patients. PVB19 (73.5%) was the most commonly identified virus in those with confirmed AM followed by EBV (12.2%), HHV6 (4.1%) and Human Bocavirus (2%). 3 were coinfected with PVB19/EBV, and 1 with PVB19/EBV/HHV6. PVB19 was also isolated in 9 patients with no evidence of AM on CMR or EMB, but with lower median viral load compared to those with AM (198copies/ml IQR 113 – 282 vs 483copies/ml IQR 366 – 1460, p=0.005). The virus-positive patients with confirmed AM tended to be older (43.1±13.4 years vs 37.6±12.2 years, p=n/s), had higher median CRP (24mg/L vs 16mg/L, p=n/s) but lower median hsTnT (326.5ng/L vs 434.5ng/L, p=n/s) at presentation, and were more likely to be EMB positive (60% vs 37.5%, p=0.04) when compared to the virus-negative group. To date 6 patients have demised, of which 4 were related to AM. To our knowledge, this is the first study to evaluate AM in Africa, and the biggest cohort of AM patients outside of the developed world. It demonstrates the heterogeneity in presentations and provides insight into the viral pathogens within our local setting, which appears similar to those reported in the developed world. We were also able to highlight some differences in demographic and clinical characteristics between those with virus-positive and virus-negative AM. The background prevalence and causal role of PVB19 in our setting will also need to be further explored. Type of funding sources: None.

The incidence and outcomes of high-risk acute coronary syndromes in Western Cape Province, South Africa: A prospective cohort study

PubMed, May 5, 2023

Background: Tygerberg Hospital (TBH) is a tertiary-level hospital in Western Cape Province, South... more Background: Tygerberg Hospital (TBH) is a tertiary-level hospital in Western Cape Province, South Africa, that provides healthcare to a large low- to middle-income population with services including centralised advanced cardiac care. Acute coronary syndrome (ACS) remains an important cause of death in the region despite a high burden of communicable diseases, including HIV. Objectives: To describe the incidence of ST-elevation myocardial infarction (STEMI) and high-risk non-ST-elevation ACS (HR-NSTEACS) in the TBH referral network, describe the in-hospital and 30-day mortality of these patients, and identify important high-risk population characteristics. Methods: The Tygerberg Acute Coronary Syndrome Registry database is an ongoing prospective study that enrols all STEMI and HR-NSTEACS patients in the TBH referral network. All patients aged >18 years presenting with STEMI or HR-NSTEACS were treated in accordance with current European Society of Cardiology guidelines and were included prospectively over a 9-month surveillance period. A waiver of consent was granted to include patients who died before giving informed consent. Data collected included a demographic profile, risk factors for cardiovascular disease, in-hospital therapy and 30-day mortality. Results: A total of 586 patients were enrolled, with a male predominance (64.5%) and incidence rates of STEMI and HR-NSTEACS of 14.7 per 100 000 and 15.6 per 100 000, respectively. The mean patient age was 58 years, and STEMI patients tended to be younger than HR-NSTEACS patients (56 v. 58 years; p=0.01). Cardiovascular risk factors were prevalent overall, but hypertension (79.8% v. 68.3%; p<0.01) and pre-existing IHD (29.1% v. 7.0%; p=0.03) were more prevalent in the HR-NSTEACS group. HIV was present in 12.6% of patients tested, similar to the background population rate. The overall 30-day all-cause mortality rate was 6.1%, with an in-hospital mortality rate of 3.9%. The 30-day mortality rates were similar for STEMI (1.8%) and HR-NSTEACS (2.6%) (p=0.75). HIV did not affect mortality rates. Conclusion: Use of a guideline-based approach to treating ACS in a low- to middle-income country setting yields mortality rates comparable to those in high-income countries. However, the lower-than-expected incidence rates of both STEMI and HR-NSTEACS in a relatively young population with a high prevalence of traditional cardiovascular risk factors, and a relatively high proportion of STEMI, suggest potential under-recording of ischaemic heart disease in the region. The rate and outcomes of coronary artery disease (CAD) in people living with HIV were similar to those in people without HIV, suggesting that traditional risk factors still drive CAD outcomes in the region.

Comparing the findings and diagnostic sensitivity of cardiovascular magnetic resonance in biopsy confirmed acute myocarditis with infarct-like vs. heart failure presentation

Journal of Cardiovascular Magnetic Resonance

Background Cardiovascular magnetic resonance (CMR) is considered the reference imaging modality i... more Background Cardiovascular magnetic resonance (CMR) is considered the reference imaging modality in providing a non-invasive diagnosis of acute myocarditis (AM), as it allows for the detection of myocardial injury associated with AM. However, the diagnostic sensitivity and pattern of CMR findings appear to differ according to clinical presentation. Methods This is a retrospective cross-sectional study. Consecutive adult patients presenting to a single tertiary centre in South Africa between August 2017 and January 2022 with AM confirmed on endomyocardial biopsy (EMB) were enrolled. Patients with infarct-like symptoms, defined as those presenting primarily with chest pain syndrome with associated ST-T wave changes on electrocardiogram, or heart failure (HF) symptoms, defined as clinical signs and symptoms of HF without significant chest discomfort, were compared using contrasted CMR and parametric techniques with EMB confirmation of AM as diagnostic gold standard. Results Forty-one pa...

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Evolution of myocardial oedema and fibrosis in HIV infected persons after the initiation of antiretroviral therapy: a prospective cardiovascular magnetic resonance study

Journal of Cardiovascular Magnetic Resonance

Background Human immunodeficiency virus (HIV) infected persons on antiretroviral therapy (ART) ha... more Background Human immunodeficiency virus (HIV) infected persons on antiretroviral therapy (ART) have been shown to have functionally and structurally altered ventricles and may be related to cardiovascular inflammation. Mounting evidence suggests that the myocardium of HIV infected individuals may be abnormal before ART is initiated and may represent subclinical HIV-associated cardiomyopathy (HIVAC). The influence of ART on subclinical HIVAC is not known. Methods Newly diagnosed, ART naïve persons with HIV infection were enrolled along with HIV uninfected, age- and sex-matched controls. All participants underwent comprehensive cardiovascular assessment, including contrasted cardiovascular magnetic resonance (CMR) with multiparametric mapping on a 1.5T CMR system. The HIV group was started on ART (tenofovir/lamivudine/dolutegravir) and prospectively evaluated 9 months later. Cardiac tissue characterisation was compared in, and between groups using the appropriate statistical tests for...

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Causes of infective endocarditis in the Western Cape, South Africa: a prospective cohort study using a set protocol for organism detection and central decision making by an endocarditis team

BMJ Open

BackgroundBlood culture negative infective endocarditis (BCNIE) poses both a diagnostic and thera... more BackgroundBlood culture negative infective endocarditis (BCNIE) poses both a diagnostic and therapeutic challenge. High rates of BCNIE reported in South Africa have been attributed to antibiotic use prior to blood culture sampling.ObjectivesTo assess the impact of a systematic approach to organism detection and identify the causes of infective endocarditis (IE), in particular causes of BCNIE.DesignProspective cohort study.MethodsThe Tygerberg Endocarditis Cohort study prospectively enrolled patients with IE between November 2019 and February 2021. A set protocol for organism detection with management of patients by an endocarditis team was employed. This prospective cohort was compared with a retrospective cohort of patients with IE admitted between January 2017 and December 2018.ResultsOne hundred and forty patients with IE were included, with 75 and 65 patients in the retrospective and prospective cohorts, respectively. Baseline demographic characteristics were similar with a mean...

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Altered cardiac structure and function in newly diagnosed people living with HIV: a prospective cardiovascular magnetic resonance study after the initiation of antiretroviral treatment

The International Journal of Cardiovascular Imaging

HIV associated cardiomyopathy (HIVAC) is a poorly understood entity that may progress along a con... more HIV associated cardiomyopathy (HIVAC) is a poorly understood entity that may progress along a continuum. We evaluated a group of persons newly diagnosed with HIV and studied the evolution of cardiac abnormalities after ART initiation. We recruited a group of newly diagnosed, ART naïve persons with HIV and a healthy, HIV uninfected group. Participants underwent comprehensive cardiovascular evaluation, including cardiovascular magnetic resonance imaging. The HIV group was started on ART and re-evaluated 9 months later. The cardiovascular parameters of the study groups were compared at diagnosis and after 9 months. The ART naïve group’s (n = 66) left- and right end diastolic volume indexed for height were larger compared with controls (n = 22) (p < 0.03). The left ventricular mass indexed for height was larger in the naïve group compared with controls (p = 0.04). The ART naïve group had decreased left- and right ventricular ejection fraction (p < 0.03) and negative, non-linear as...

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Echocardiographic features of infective endocarditis in South Africa: A prospective cohort study

South African Medical Journal

Background. Historically, infective endocarditis (IE) in South Africa (SA) was associated with th... more Background. Historically, infective endocarditis (IE) in South Africa (SA) was associated with the viridans group of streptococci affecting patients with underlying rheumatic heart disease (RHD). A changing IE bacteriological profile raises the question of whether the profile of underlying valvular abnormality has changed. Objectives. To investigate the prevalence of underlying structural valve abnormalities and their aetiologies associated with IE in SA, and describe the typical imaging findings. Methods. The Tygerberg Endocarditis Cohort study prospectively enrolled patients with IE between November 2019 and April 2021. Patients underwent detailed transthoracic and transoesophageal echocardiography to assess their underlying cardiac and valvular structure. Results. Among 71 patients included, a predisposing endocardial abnormality was detected in 49.3%, with RHD the most common single identifiable aetiology (16.9%). The in-hospital mortality rate was similar in patients with and w...

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Infective endocarditis in Africa: an urgent call for more data

The Lancet Global Health, 2022

Valvular heart disease associated with systemic lupus erythematosus - the Tygerberg Hospital experience

Cardiovascular journal of South Africa : official journal for Southern Africa Cardiac Society [and] South African Society of Cardiac Practitioners, 2000

BACKGROUND: Valvular heart disease is the most important cardiac manifestation of systemic lupus ... more BACKGROUND: Valvular heart disease is the most important cardiac manifestation of systemic lupus erythematosus (SLE). We performed a study to determine the presence of valvular heart disease in our patients with SLE. METHODS: We performed clinical, electrocardiographic, transthoracic echocardiographic and laboratory evaluations in 24 patients with SLE. The echocardiographic findings were compared with those of 10 age- and sex-matched volunteers. RESULTS: None of the 24 patients had obvious symptoms of cardiac origin. Valvular abnormalities were common. Valvular thickening was the most predominant finding (more than 50%), followed by mitral valvular regurgitation (12.5%) and pericardial effusions (12.5%). Valvular abnormalities were uncommon in the control group. CONCLUSION: Valvular heart disease is common in our patient population with SLE, although haemodynamically significant valvular dysfunction is rare.

P5519Radial artery dilatation to improve access and lower complication rates during coronary angiography (RADIAL): a randomized controlled trial

European Heart Journal, Aug 1, 2018

To evaluate efficacy and safety of trans ulnar access for coronary angiography and interventions.... more To evaluate efficacy and safety of trans ulnar access for coronary angiography and interventions. Methods: A prospective cohort study was conducted in 73 patients who underwent coronary angiography and/or percutaneous coronary intervention at thammasat university hospital from May 2016 to July 2017. Transulnar access was done in patient with normal Allen's test. Procedure was performed by single operator. Primary endpoint was a success rate of vascular access. Secondary endpoints was fluoroscopy time, vascular access time, procedure time for diagnostic coronary angiography, contrast volume during diagnostic coronary angiography ulnar spasm, hematoma of access site, ulnar artery occlusion after procedure Results: Of 73 patients (age 63±14 year, 42.5% Female), 79% (58 patients) was successful transulnar access. The mean vascular access time was 4.8± 5.7 minutes and mean procedural time was 67.17± 57.08 minutes which 54.8% (40 patients) underwent percutaneous coronary intervention. Nine patients (12%) developed ulnar artery spasm during procedure and five patients (6.8%) had significant access site hematoma. No ulnar artery occlusion was demonstrated by Doppler colour ultrasound within one week. Conclusion: Transulnar access was safe and efficacy for patients undergo coronary intervention. This supports the safety and efficacy of transulnar access as an alternative access to transradial approach in patients who had radial access site limitation.

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Infective endocarditis in the Western Cape of South Africa : a three-year prospective study : general cardiology

Cardiovascular journal of South Africa, Oct 1, 2002

Ewart's sign in tuberculous pericarditis

PubMed, Nov 1, 2000

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The role of histopathology in establishing the diagnosis of tuberculous pericardial effusions in the presence of HIV

Histopathology, Feb 1, 2006

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