Physical activity and sports in heart failure due to myocarditis and dilated cardiomyopathy

Abstract

Sudden cardiac death of suspected healthy young athletes is a rare, but deeply moving event. Usually, the affected person has been completely free of symptoms. Commonly, unrecognized inflammatory, hypertrophic or dilated cardiomyopathies are the most frequent causes. All therapeutic principles of angiotensin-converting-enzyme (ACE) inhibition, beta-blockade, and diuretics in heart failure aim to unload the heart. During physical activity increased sympathetic tonus and loading conditions for the heart point into the opposite direction. This raises the question to what extent physical activity in patients with myocarditis, dilated cardiomyopathy or heart failure in general is tolerable. Several experimental studies revealed disadvantages of physical exercise during acute myocarditis leading to an increase in mortality. On the other hand, several small trials in men demonstrate an improvement of physical fitness and quality of life attributed to controlled supervised exercise training in patients with heart failure without assessment of mortality. Dilated cardiomyopathy was diagnosed in one third of these patients. There was no biopsy confirmation of these conditions. The other two thirds of patients suffered from ischemic heart diseases. Since the borderline between inflammatory heart disease and noninflammatory or postinflammatory dilated cardiomyopathy is difficult to determine, abstention from physical training during and shortly after inflammatory heart disease is recommended, because it is known that viral persistence or autoimmune processes could last for several months.