Exercise and heart disease: from athletes and arrhythmias to hypertrophic cardiomyopathy and congenital heart disease.

The beneficial effects of regular physical activity on cardiovascular health are well established, with convincing evidence of improvements in blood pressure, lipid profile and overall mortality. Conversely, individuals with pre-existing congenital, inherited or acquired heart conditions may experience functional cardiac deterioration or sudden death during even moderate exertion. Exclusion from high-level sporting activity may be mandated in some cases, and pre-participation screening of competitive athletes plays an important role in the identification of such individuals. The issue of screening is complicated by the fact that physiological cardiovascular adaptation in healthy athletes, including modest left ventricular hypertrophy and biventricular cavity dilatation, may create a diagnostic overlap with pathological conditions such as hypertrophic cardiomyopathy. Furthermore, much interest has focused recently on the possibility of irreversible cardiac remodeling in a proportion of veteran endurance athletes, with the potential for arrhythmogenesis and adverse cardiac events.