Captopril-induced changes in large arteries in essential hypertension.

The effect on large arteries of the converting enzyme inhibitor captopril was studied in men with sustained essential hypertension with two different hemodynamic parameters: (1) systemic arterial compliance and (2) brachial artery diameter. After captopril administration, a 20 percent increase in arterial compliance was observed. The same increase was obtained with a 5 percent (acute experiment) and a 15 percent (short-term experiment) decrease in blood pressure, indicating that the decrease in pressure could not explain exclusively the increase in compliance. This assumption was studied with determinations of brachial artery diameter using original pulsed Doppler systems. After captopril administration, brachial artery diameter increased markedly despite the decrease in blood pressure. In addition to its effect on small arteries, the converting enzyme inhibitor captopril also has a special effect on the large arteries of patients with essential hypertension.