[Two-dimensional stress echocardiography and plasma catecholamine measurements in the evaluation of the physiologically hypertrophied heart].

Two-dimensional stress echocardiography was performed in 8 untrained subjects, 8 long-distance runners, and 8 cyclists. The ergometric investigation was performed with subjects in supine position on a bicycle ergometer with increasing work loads of 50 Watts. At each working level, lactate, norepinephrine, and epinephrine were measured. The long-distance runners and the cyclists had an equal maximum oxygen uptake when tested with treadmill or bicycle ergometer. Absolute and relative heart volumes also showed the same amount of hypertrophy. In spite of this, lactate, catecholamines, and heart rate of the long-distance runners rose earlier during the supine ergometer test. End-diastolic volume and stroke volume in the cyclists increased significantly more (delta EDV = 15%, delta SV = 32%) than in the long-distance runners (delta EDV = 1%, delta SV = 13%) and untrained subjects (delta EDV = 5%, delta SV = 9%). It is assumed that this difference in heart function is caused by diminished sympathetic activity, which is dependent on the aerobic capacity of the working muscles.