The danger posed to athletes in competitive sports diagnosed with an irregular heartbeat has prompted doctors to urge they end their careers. Many patients ignore that advice and, according to a new study published in the American Heart Association's journal, Circulation, they may some science to back the decision.
Dr. Rachel Lampert, a cardiologist with Yale University, opened a national registry to track 372 high school, college and young adult athletes fitted with an implantable cardioveter defibrillator, or ICD, over a 31 month period. The devices fired more during physical activity. Of the 121 shocks administered to 77 of the subjects during the study, 65 of them occurred during some kind of physical activity.
None of the subjects died, required resuscitation, or experienced injury due to the defibrillator's shock.
“For a long time, the recommendation was, regardless of what [kind of heart] disease you had, if you're felt to be at risk for an arrhythmia, and, therefore have an ICD, you shouldn't be doing sports,” said Lampert.
Despite none of the participants fitting the typical profile of an older patient with heart failure, half of the patients in the study had a prior life-threatening palpitation, with the other half at high risk for one. The American College of Cardiology and the European Society for Cardiology in 2005 issued a consenus report that led to the decision to place a blanket restriction on athletes with ICDs.
“The concern was we didn't know whether the ICD would work well during sports,” Lampert said. “In general, ICDs work extremely well. When you exercise, things change in your body: the salt, lactic acid and other buildups. The concern was the shock wouldn't work as well when those conditions changed.”
Though the results are promising, Lampert, her colleagues and critics, alike, still have concerns. High- intensity sports like basketball and tennis are fine, according to the study. It still remains unclear whether more aggressive sports like football and hockey are in that category also.
“The problem with football is that it's a contact sport. All that motion and if somebody hits the chest there's a risk of injury to the device or to the read system,” said Dr. Christine Lawless, co-chairwoman of the American College of Cardiology Council on Sports and Exercise Cardiology. “It makes you wonder, if we put in these devices in January and the football season is from April to December, is it going to consistently work all the time during those practices?”
Dr. Arthur Moss, a University of Rochester cardiologist who led the research that resulted in the expanded use of ICDs, shares those concerns more broadly. Though the risks are small, they aren't negligible, which he feels doesn't make playing sports worth the risk.
“The benefits seem mostly psychological, that the patient is allowed to play,” he said. “The risk is that the patient might die, and has a higher risk than a healthy athlete. I'm a big proponent of ICDs, but they don't work every time. The study didn't focus on the individual risk for each patient.”
For those who are willing to take that risk, the study represents a bit of hope.
“People don't want to be told by their doctor that they can't do anything,” Lawless said. “We're in a an era of possibility, where that old way of thinking people just don't want.”