[Anatomical and functional changes in the heart caused by physical stress shown in M-mode echocardiography]

The paper focuses on the determination of echocardiographic standard values for male and female standard persons between the age of 10 and 30 (n = 180), the determination of the physiological extreme variants of competitive athletes (n = 148) and the analysis of the mode of operation of the heart at rest and during physical stress of the trained and untrained heart (n = 45). Body weight and body surface are both equally suited as reference values for the specification of echocardiographic standard values. Echocardiographic index values relative to the body surface (mm/m2) cannot be used as standard values for persons with different body measurements. Under long-term intensive stress of training an adaption of the heart in the sense of an eccentric hypertrophy occurs in the case of endurance athletes, while in the case of strength athletes a cardiac adaption towards a concentric hypertrophy may be noted. During dynamic physical activity (50 and 100 W) hearts of different sizes at the same levels of stress show clear differences with regard to the changes in size resulting from physical stress and with regard to contractility. Related to equal heart rate as an indication for an equal sympathetic impulse, however, the reaction of hearts of different sizes resulting from physical stress is almost identical.