ARTERIAL STIFFNESS, HYDROCHLOROTHIAZIDE AND CONVERTING-ENZYME INHIBITION IN ESSENTIAL-HYPERTENSION

In a randomized double blind study, the arterial changes produced eith er by hydrochlorothiazide plus amiloride (Group I), or by hydrochlorot hiazide plus captopril (Group II) were investigated in two territories of the arterial tree, the common carotid artery and the terminal aort a. Arterial echo-tracking techniques of high resolution and applanatio n tonometry were used to evaluate non-invasively the indices of arteri al stiffness and carotid wave reflections. In Groups I and II, there w as a similar significant decrease in brachial blood pressure (BP) and carotid diastolic diameter and an increase in aortic compliance and di stensibility. Groups I and II differed significantly in aortic diastol ic diameter which decreased in Group I but not in Group II, and in car otid wave reflections which were modified in Group II but not in Group I. Thus, captopril associated with hydrochlorothiazide resulted in a shift in the carotid arterial reflection wave from systole to diastole with no reduction in the aortic diastolic dimension. For similar BP r eduction, the combination of hydrochlorothiazide and amiloride had no significant effect on the carotid reflection wave, but caused a signif icant reduction in the aortic diastolic diameter. These intergroup dif ferences were related to the presence or absence of converting enzyme inhibition.