WEDNESDAY, June 3, 2015 (HealthDay News) -- Endurance athletes should be tested for potentially deadly heart rhythm problems when they are exercising rather than resting, and the tests should include the right ventricle as well as the left ventricle, a new study says.
Some athletes who participate in endurance events such as marathons and triathlons may have heart rhythm disorders (arrhythmias) that can cause sudden death.
A team of researchers from Australia and Belgium found that important signs of rhythm problems in the heart's right ventricle can only be detected during exercise, according to the study published June 3 in the European Heart Journal.
Currently, most routine assessments of athletes with suspected heart rhythm problems are done when the patients are resting, and the focus is on the left ventricle, the investigators said.
"You do not test a racing car while it is sitting in the garage. Similarly, you can't assess an athlete's heart until you assess it under the stress of exercise," study author Dr. Andre La Gerche, head of sports cardiology at Baker IDI Heart and Diabetes Institute in Melbourne, Australia, and visiting professor at University Hospitals Leuven, Belgium, said in a journal news release.
He and his colleagues tested the performance of the hearts of 17 endurance athletes with right ventricular arrhythmias, 10 athletes without heart problems, and seven nonathletes.
Heart function during rest was similar in all three groups, as was left ventricular function during exercise. However, right ventricular function during exercise was different among the athletes with arrhythmias compared to the other two groups.
"By measuring the blood pressure in the lungs and the body during exercise we have shown that the right side of the heart has to increase its work more than the left side of the heart. Hence, the right side of the heart is a potential 'weak link' in athletes," La Gerche said.
"In the normal healthy athletes, the right side of the heart was able to manage the increased work requirements. In the athletes with arrhythmias, the right side of the heart was weak during exercise, it could not handle the increase in work and we could detect problems accurately that were not apparent at rest," he explained.
"The dysfunction of the right ventricle during exercise suggests that there is damage to the heart muscle. This damage is causing both weakness and heart rhythm problems. Whilst the weakness is mild, the heart rhythm problems are potentially life threatening," La Gerche concluded.
The findings show that "assessment of the right ventricle should form an integral component of risk assessment in athletes presenting with potentially lethal rhythm disturbances," Dr. Sanjay Sharma, of St. George's University of London and medical director of the London Marathon, and Abbas Zaidi, a research fellow at St. George's, wrote in an accompanying editorial.
The American Heart Association has more about arrhythmia.