Athletes screened for underlying cardiovascular conditions that could put them at risk of sudden cardiac death are either being over tested or at risk of having critical conditions missed because of incorrect ECG interpretation, an expert group has warned.
In an international consensus statement, sports cardiologists, inherited cardiac disease specialists, and sports medicine specialists have said that physicians responsible for the cardiovascular care of athletes should be guided by ECG interpretation standards that improve disease detection and limit false-positive results.
Head of Sports Cardiology at Baker IDI, Associate Professor Andre La Gerche, who was involved in developing the recommendations, has studied over 2,500 Australian elite athletes using ECGs.
Speaking to the limbic, he said that ECG interpretation in athletes is a nuanced area but there is little formal training in sports medicine for cardiologists.
According to Professor La Gerche, its not uncommon for a healthy athlete with a ‘big heart and big atria’ to have been sent away for a ‘cascade of tests’ that could have been avoided simply by being familiar with the ECG alterations that occur in people who participate in regular athletic training.
“People with the biggest fitness capacities, professional cyclists, cross country skiers for example, their hearts are two to three times bigger than a normal person’s heart,” he said.
“They will have unique electrical manifestations that might reflect enlarged cardiac chamber size and increased vagal tone on an ECG for instance or a severely dilated heart or borderline wall thickness on an echo but these findings in athletes are considered normal, physiological adaptations to regular exercise and don’t require further investigation.”
But, while over diagnosis is one concern, on the other side of the coin Professor La Gerche says that some athletes will have serious underlying cardiovascular conditions missed precisely because clinicians are aware that athletes can present with ECGs that are different to the general population.
“There are many occasions where clinicians have mistaken a clearly abnormal ECG as part of the ‘athlete spectrum’. These are mistakes that are made by the best – and made often.”
While Professor La Gerche is himself not a proponent of mandated ECG screening in athletes, he says more Australian professional sporting associations are moving to implement the practice – a move that, for some athletes, could set off a ‘whole cascade of disaster’ if the ECGs aren’t interpreted correctly.
“If screening is going to be done it really needs to be done well – you wouldn’t have a mammogram done by someone who has never read a mammogram, yet at the moment these ECGs are sometimes being looked at by people who have seen an elite athlete’s ECG for the first time and that’s because a lot of sporting bodies have told athletes that they need to be screened but have not provided any framework for that.
“Often the person assessing the ECG may not even know they’re assessing an athlete and that’s a bad system,” he told the limbic.
According to Professor La Gerche cardiologists who suspect an abnormal ECG should speak to someone with a special interest in athletes before ordering additional tests.
“Because more often than not, what looks like an abnormality will often be quite normal for an athlete.”