SUDDEN CARDIAC DEATH AND THE ATHLETES HEART

Objectives: To review the current literature pertaining to the cardiov ascular adaptations to exercise and the impact on the physical examina tion: the electrocardiogram, and the echocardiogram, and to distinguis h those physiologic changes from pathologic conditions associated with sudden cardiac death in athletes. Data Synthesis: Specific cardiovasc ular adaptations occur in response to regular physical exercise. The e xtent of these changes depend on the type and duration of exercise as well as the gender of the athlete. These cardiac adaptations are morph ologically different from those conditions associated with sudden card iac death. In the athlete younger than 35 years, hypertrophic cardiomy opathy is the most common cardiac condition associated with sudden dea th. Right ventricular dysplasia, idiopathic left ventricular hypertrop hy, coronary anomalies, premature atherosclerosis, and Marfan syndrome compose the majority of the remaining causes of sudden cardiac death in athletes. In the athlete older than 35 years, coronary atherosclero sis is the leading cause of sudden death followed by those conditions responsible for sudden death in the younger athlete. Despite this, reg ular exercise before or following a myocardial infarction provides a p rotective effect with respect to overall mortality, cardiovascular mor tality, and fatal reinfarction rates. Conclusions: Cardiovascular adap tation to regular physical exercise leads to morphologic changes in th e myocardium that influence the cardiac examination, the electrocardio gram, and the echocardiogram. Knowledge and recognition of those chang es can allow the clinician to distinguish normal physiologic changes f rom cardiac abnormality. Proper detection of athletes at high risk for sudden cardiac death and abstention from vigorous physical activity i n these athletes may prevent sudden death.