Effect of ramipril on 24-hour variability of blood pressure and heart rate in essential hypertension.

Nonrestricted blood pressure recording was performed invasively or noninvasively, using new portable devices, for a period of 24 hours in 4 patients with essential hypertension before and after 6- to 17-day treatment with ramipril at an initial dosage of 1.25 mg daily. Ramipril produced a steady decrease in blood pressure without changing heart rate. Before initiation of ramipril treatment, the blood pressure was lower during the night than during the day. This day to night difference was not affected by ramipril. In addition, analysis of the standard deviation of the mean for each time point examined during 24 hours revealed no effect of ramipril on circadian variation of blood pressure.