This finding also suggests that the practice of taking aspirin before a race to prevent cardiac arrest is likely ineffective, since acute coronary artery thrombosis is not an important cause of marathon-related cardiac arrest, they added.
Physicians called on to evaluate potential marathon participants "should be aware of the risks of hypertrophic cardiomyopathy and atherosclerotic disease in this patient population." Prerace exercise testing may detect physiologically significant coronary artery stenosis or may identify patients with exertion-induced myocardial ischemia, the investigators said.
This study was limited in that the researchers were unable to obtain complete clinical information on 45% of the nonsurvivors or on 53% of the survivors.
Dr. Kim reported no financial conflicts of interest, but two of his coauthors reported ties to industry sources.