Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a rare inherited heart condition that has long been recognised as an important – yet elusive – cause of sudden cardiac death among young athletes.
However, new research funded by the charity Cardiac Risk in the Young (CRY) is challenging the conventional belief that ARVC is predominantly a disease of the right ventricle and found that left ventricular involvement is also common irrespective of athletic activity.
The study, due to be presented this week at the British Cardiovascular Society in Manchester, reported on 98 young sudden death victims found to have ARVC at expert post-mortem. In the overwhelming majority (84%) of cases, there was involvement of the left ventricle, a finding that was indistinguishable between young individuals engaged in competitive sport and non-athletes.
Dr. Chris Miles, CRY research fellow and lead author of the research, said: “This study gives greater support to the notion that ARVC should now be referred to as ‘arrhythmogenic cardiomyopathy’, recognising that, in the majority of cases, both sides of the heart appear to be affected. We know that adaptive changes occur within the right ventricle after sustained exercise, however, given the high proportion of athletes with left ventricular involvement, it is unlikely exercised-induced changes alone can result in ARVC.”
Over a third of the young ARVC sudden death victims were engaged in competitive sport, principally high intensity sports such as football. They were also far more likely to have died during physical exertion. At post-mortem, athletes had evidence of right ventricular enlargement alongside increased weight of the heart, consistent with the changes observed following prolonged athletic training.
ARVC is caused by a defect in the “glue” that holds heart muscle cells together. As the heart muscle is continuously under stress, the connections between cells can become damaged, ultimately leading to cell death and replacement with fat and fibrous tissue. This can lead to devastating disturbances in the heart’s electrical rhythm, often during physical activity. In most individuals, these changes lead to abnormalities on the electrocardiogram (ECG), and in approximately half of cases, a disease-causing gene mutation can be identified.
Professor Mary Sheppard, senior author of the study at St George’s University of London and Director of CRY’s pioneering Cardiac Pathology Centre has evaluated over 5,000 cases of mainly young sudden cardiac death over the last two decades.
Understanding inherited cardiac conditions such as ARVC has underpinned the research ethos of CRY since it was founded in 1995. The charity was inspired by the Lancashire family of a gifted, 16-year-old footballer, John Marshall who tragically died from ARVC, just days before he joined Everton Football Club.
The research into ARVC was then launched by the family of father and son, Howard and Sebastian English (from Haslemere, Surrey). Both died from ARVC – 11 years apart. The link had never been made until Sebastian’s tragic death in 2004, aged just 15. The family has since raised over £600,000 to support the CRY Centre for Cardiac Pathology to improve understanding of ARVC and how deaths can be prevented. In 1995, it was believed that ARVC affected 1 in 5-7 million of the population – the figure is now known to be closer to 1 in 2-3000.
Every week, 12 apparently fit and healthy young (aged 35 and under) people in the UK die suddenly from an undiagnosed heart condition. In 80% of cases there will have been no signs or symptoms which is why CRY believes proactive cardiac screening is so vitally important – for all young people, whether an elite athlete, non-athlete or grass-roots sportsperson. As such CRY now tests around 27,000 young people each year aged between 14 and 35 and over 165,000 since the screening programme was launched in 1995. One in every 300 young people tested by CRY will be identified with a potentially life-threatening condition.
Dr Steven Cox, Chief Executive of CRY, adds; “Our understanding of arrhythmogenic cardiomyopathy – or ARVC as it has been widely referred to for many years – is currently reaching a pivotal time.
“Not only is Chris’ research highlighting a greater understanding of this devastating condition that can suddenly strike so many talented athletes at the prime of their lives, but pre-participation screening for conditions such as ARVC is being increasingly recommended to help detect the condition in asymptomatic patients – which will also have a big impact in helping cardiologists to make decisions about the safety of some athletes continuing to play their sport.
“Greater recognition and understanding of these conditions which can have such a horrendous impact if left undiagnosed is something that families connected to CRY are continually fighting for and I’m very proud that one of our funded Research Fellows is feeding our latest findings into the growing international body of research.”
Notes to editors:
Dr Miles was recently awarded the Young Investigator Award in Sports Cardiology at EuroPrevent 2018. Commenting on the accolade, he said;
“The Young Investigator Award provides an excellent opportunity to present work at international level and is well recognised by colleagues within the field. I would like to thank Dr Elijah Behr, Professor Mary Sheppard, Dr Michael Papadakis and Dr Gherardo Finocchiaro at St George’s University, in addition to Cardiac Risk in the Young (CRY) for its essential role in funding the CRY Centre for Cardiac Pathology. CRY is supported by hundreds of families affected by young sudden cardiac death and we hope to continue to make important progress into researching one of its important causes. “
The CRY Centre for Inherited Cardiovascular Conditions & Sports Cardiology was first launched in April 2010, under the leadership of Consultant Cardiologist, Professor Sanjay Sharma.