(NEW YORK) -- Though relatively rare, a cardiac event that strikes a young person at practice or play is often deadly. About 100 young people die every year playing organized sports, and cardiac arrest is the cause in half the cases, according to the National Athletic Trainers' Association (NATA).
Dr. Dominique Abrams, a cardiologist at Boston Children's Hospital, said cardiac conditions in young people typically fall into one of two categories.
The first, cardiomyopathies, involve some abnormality of the heart such as enlargement, thinning walls or scaring. The second type is caused by rhythm disturbances. Nothing appears wrong with the heart but it has a tendency to beat irregularly in some way.
Abrams said that at-risk children and young adults can experience a heart event any time but that exercise certainly increases the chances.
"Patients can be at home watching TV when it happens," he said. "But we know that symptoms might be exacerbated during sports because their adrenaline is pumping, causing the heart to beat faster."
High school players of hard driving sports like basketball, football and hockey are not the only ones at risk either -- though their stories are the ones that usually make the news. Abrams referenced a subtype of Long Q-T syndrome that's associated with swimming deaths.
"It's thought to be brought on by the 'diving reflex,' which triggers sudden changes of heart rate and may cause loss of consciousness -- an inherently dangerous occurrence in a pool," he said.
American Heart Association studies show that young black athletes have a greater incidence of cardiovascular death than whites. And a Dutch study in the Journal of American Cardiology found that 68 percent of cardiac arrest cases during sports play were boys.
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