[The hemostatic and fibrinolytic system in normal subjects and myocardial infarct patients. Effect of a standardized aerobic and anaerobic ergometric stress test].

After clinical examination, 14 asymptomatic post-infarction male patients and 12 healthy control persons, aged 35-62 years, underwent two bicycle-ergometry tests. After a 20-min aerobic test of moderate intensity both groups had slight activation of the clotting system simultaneously with favorably increased fibrinolytic activity. After stepwise submaximal aerobic exercise, postinfarction patients had marked activation of the thrombocytic system; beta-thromboglobulin rose significantly from 36 to 102 ng/ml. But compared to the results in healthy persons, fibrinolytic activity was significantly reduced in the postinfarction patients (euglobulin lysis time 135 and 100 min, respectively). In three patients with unfavorable reactions of the hemostasis and fibrinolysis systems, ischemic changes or multifocal ventricular extrasystoles were recorded in the ECG after the second exercise test. These results indicate that intensive physical exercise in postinfarction patients can change the dynamic equilibrium between hemostasis and fibrinolysis in the direction of an increased clotting tendency. For this reason postinfarction patients and elderly untrained persons, especially those with an increased coronary risk factor, should avoid endurance training involving anaerobic exercise. On the other hand, moderate training at aerobic level favorably influences the hemostatic equilibrium in both healthy and postinfarction patients.