Abstract

The effects of long-term treatment with diltiazem on blood pressure, central haemodynamics and exercise endurance were studied in 16 min (mean age 52 years) with essential hypertension. Intra-arterial pressure and heart rate (HR) were monitored continuously: Cardiac output (CO) was measured by Cardiogreen at rest (supine and sitting) and during 50 W, 100 W and 150 W bicycle exercise. Haemodynamic measurements were repeated after continuous bicycling at 150 W for 20 min or until exhaustion. After 1 year on diltiazem (mean daily dose 278 mg) intra-arterial pressure was reduced in all situations (at rest sitting from 183/108 mmHg to 157/92 mmHg (14)) due to reduction in total peripheral resistance. HR was reduced at rest (7) and during exercise (10). Stroke volume tended to increase while CO was unchanged. Exercise time at constant workload increased by 25. After a peak level, intra-arterial pressure fell by 3 to 5 due to a decrease in total peripheral resistance both before and during diltiazem treatment. Stroke volume and CO remained unchanged during endurance exercise while HR showed a small increase. Thus, there was no reduction in the overall cardiac pump function after long-term diltiazem treatment, and blood flow during exercise was maintained. Verf.-Referat