EFFECTS OF RAMIPRIL ON ARTERIAL HEMODYNAMICS

The acute and chronic arterial effects of the angiotensin-converting enzyme (ACE) inhibitor ramipril were studied in hypertensive patients. Hemodynamic and biological parameters were measured 3 h after the first dose of 5 mg of ramipril, and then again after 4 weeks of treatment, 3 and 24 h after drug administration. Brachial and carotid artery hemodynamics were evaluated using a two-dimensional pulsed Doppler system. Arterial distensibility was studied noninvasively in three arterial segments (carotidofemoral, brachioradial, and femorotibial) by evaluating the pulse wave velocity. Ramipril lowered the blood pressure significantly after acute and chronic administration. Chronic treatment with ramipril was followed by a long-lasting increase in brachial artery diameter, a decrease in forearm vascular resistance, and an improvement in aortic distensibility. The other arterial segments studied did not show any significant changes. Our results suggest that the long-lasting arterial effects of the ACE inhibitor ramipril are partly pressure independent and are related to effects on arterial tone that may reduce the cardiovascular abnormalities associated with hypertension.