[Differential diagnosis: physiologic-pathologic hypertrophy of the heart. A case report].

We report on a 52-year-old asymptomatic patient, whom we have examined regularly since 1981. The principal finding is a marked terminal negativity of the T-wave in the extremities and left precordial chest leads in the electrocardiogram with regression at high exercise levels. The patient engages intensively in sports (running, cross-country skiing, gymnastics). His performance capacity is above normal at 4.5 (1981) and 3.8 watts/kg body weight (1988). The echographically determined left ventricular muscle mass (LVM) increased from 2.1-2.3 g/kg body weight to 2.9 g/kg, the end-diastolic thickness of the septum from 9 to 13, and the posterior wall from 8 to 12 mm. In physiological cardiac hypertrophy (athlete's heart), a LVM of 2.9 g/kg is not unusual, whereby the end-diastolic wall thickness does not, exceed 10 to 11 mm and the mass-volume ratio (LVM/end-diastolic ventricular volume) remains constant (about 1.2 g/ml) in contrast to the 1.75 g/ml in our patient. Thermodilution catheter examination of the heart showed a pathological increase in mean pulmonary capillary pressure (26 mm Hg) under exercise as an indication of impaired left-ventricular function. Normal myocardial scintigraphy (resting and exercise) and a lack of symptoms permit the exclusion of relevant coronary heart disease. We diagnosed non-obstructive hypertrophic cardiomyopathy. The problems of differentiating between physiological and pathological cardiac hypertrophies are discussed.