New research highlights risk of 'false positives' among black athletes following cardiac testing

Published paper is ‘Editor’s Pick’ in April 30th issue of Circulation; and underlines the need for expert screening and diagnosis to prevent unnecessary disqualification of elite athletes.
Researchers funded by CRY have published new research in one of the world’s leading cardiology journals, ‘Circulation’, which highlights the importance of expertise when conducting cardiac screening, because of the potential for black athletes to be misdiagnosed with conditions that could cause sudden cardiac death. (see the full article here)

Dr Abbas Zaidi

The paper, led by Dr Abbas Zaidi (right), looks at new and specific differences in the ‘behaviour’ of the heart of black athletes which could lead to a false positive and in some cases, unnecessary disqualification from competitive sport. Dr Zaidi is a CRY-funded Research Fellow and one of Professor Sanjay Sharma’s research team at the CRY Centre for Inherited Cardiovascular Conditions and Sports Cardiology, St George’s Hospital, London.

It is widely understood that healthy changes can occur in the heart due to regular and intense exercise – a phenomenon that is termed as ‘athlete’s heart’. This is already taken into account when athletes, of all ethnic backgrounds, are screened for underlying abnormalities.

This latest research, carried out between 2006 and 2012, used ECG (electrocardiogram) and echocardiography to study 675 elite male and female athletes – of whom 300 were black. They were also compared to a control group of non-athletic people – that is, people who do less than two hours exercise a week.

Dr Zaidi says; “We already know that when people do regular exercise the wall of the left ventricle gets thicker and the left ventricular cavity size gets bigger. We also know that these changes on the left side of the heart occur more in black athletes than white athletes. Recently, there has been more research and a greater understanding of the right side of the heart which is showing that the right ventricle can also enlarge and start to mimic a known condition called arrhythmogenic right ventricular cardiomyopathy (ARVC), which causes around 22% of young sudden cardiac deaths in athletes across Europe. Our research found that this enlargement is essentially the same whether you are black or white.”

However, perhaps the most significant finding was that almost 10 times as many black athletes as white athletes who were found to have an enlarged right ventricle, were also displaying abnormalities in their ECG results known as an anterior T-wave inversion. Such results would normally lead to an automatic diagnosis of ARVC and, in line with current guidelines, the athlete would then be advised to withdraw immediately from competitive sport.

Yet, the data strongly suggests that this diagnosis might not necessarily be correct for all black athletes, in whom right ventricular enlargement with anterior T-wave inversion appears to be a normal ethnic variant. These findings reinforce the fact that screening needs to be carried out by clinicians who are experts in sports cardiology and can identify changes that can occur normally in the hearts of those who exercise regularly, whatever their ethnicity.

Every week in the UK, 12 seemingly fit and healthy young people under the age of 35 die from sudden cardiac death. Many – although not all – of these young people were regular participants in sport. 80% of those that die have no symptoms, so the only way to identify a problem is through screening.

In Italy, athletes undergo a unique mandatory state-sponsored cardiovascular screening programme that incorporates clinical history, physical examination and a 12-lead ECG. Data from this 30 year model has shown a fall in sudden cardiac death rates of 90%.

Professor Sanjay Sharma, Consultant Cardiologist for CRY concludes; “It is absolutely vital that cardiologists understand the fundamental differences between a ‘normal’ heart, an athlete’s heart and a black athlete’s heart; and that the appropriate considerations are taken on board when these individuals are being routinely screened. Whilst we are rightly focused on identifying and treating athletes – as well as young people at grass roots level – we cannot underestimate the impact of giving a professional athlete at the start of a promising a career, a false positive result. At the very least, this causes undue anxiety for them and their family, but ultimately may also have a serious financial and social effect, as well as a lifetime of unnecessary screening and insurance implications for their family.”

CRY’s acclaimed screening programme, which was first launched in 1995, now tests around 12,000 young people every year. It also forms part of a wider research programme that is building on understanding of the incidence of cardiac conditions in young people and informing national policy on best practice, to minimise the incidence and impact of young sudden death.

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For more information about the published article in ‘Circulation’ or to request an interview with Professor Sharma or Dr Steve Cox (CRY Director of Screening), please call Jo Hudson in the CRY Press Office on 020 7112 4905 / 0770 948 7959 or email