The effect of captopril on heart rate in several types of hypertensive patients

Captopril, an orally active converting enzyme inhibitor, was administered in a dose of 50 mg to 88 untreated hypertensives (70 essential hypertensives, 8 patients with renal arterial disease, 10 patients with renal parenchymal disease). Captopril caused a decrease in heart rate in 18 patients, but an increase in 2 patients. In the remaining 68, the heart rate did not change. As a whole, captopril caused a significant decrease in blood pressure without a compensatory increase in the heart rate. The change in heart rate caused by captopril in patients with renal arterial disease was significantly higher than that in essential hypertensives. A significant negative correlation was observed between the change in heart rate and plasma renin activity obtained immediately before captopril administration (n=79, r=-0.425, p<0.001).