Effects of diltiazem hydrochloride on the reduction of blood pressure, and cardiac and renal functions in essential hypertensive patients with renal dysfunction.

Diltiazem hydrochloride was administered at a dose of 180 mg/day for 12 weeks to 10 essential hypertensive patients with slightly or moderately decreased renal plasma flow (RPF) in order to study its antihypertensive effect as well as the effects on cardiac and renal functions. The administration of diltiazem hydrochloride produced significant decreases in systolic pressure, diastolic pressure, and mean blood pressure. Right and left ventricular ejection fractions, max. dv/dt, and min. dv/dt assessed by cardiac pool scintigraphy were slightly increased, but these changes were not statistically significant. The glomerular filtration rate (GFR) and RPF were slightly increased, while renovascular resistance (RVR) was significantly reduced. No consistent tendency was observed in changes in plasma renin activity (PRA) and plasma aldosterone level. From these results, it was suggested that diltiazem hydrochloride is a potent antihypertensive drug which has no adverse effects on cardiac and renal functions in the treatment of essential hypertensive patients with slightly or moderately decreased RPF.