Haemodynamic effects of perindopril in essential hypertension.

Blood pressure, forearm arterial haemodynamics and echocardiographic parameters were studied in patients with sustained essential hypertension before and after administration of the ACE inhibitor, perindopril. In a single blind study versus placebo, perindopril significantly reduced BP and at the same time increased brachial artery diameter, blood flow and compliance. As part of the haemodynamic investigation, a 5 minute wrist occlusion was performed. During this period, blood flow velocity and arterial diameter decreased but the reduction in diameter was smaller with perindopril after one year's treatment showing an increase in brachial artery diameter. This result indicates that the increase in brachial arterial diameter following perindopril could not be explained solely on the basis of a flow dependent dilation. When perindopril was withdrawn after three months of treatment and replaced by placebo for four weeks, BP and forearm arterial haemodynamics returned towards baseline values. However, cardiac mass which was significantly decreased after perindopril remained decreased four weeks after cessation of treatment. In the seven normalised patients, perindopril was continued for one year; arterial compliance remained increased and cardia mass diminished. The study showed that the arterial changes caused by perindopril involved a drug-related relaxation of arterial smooth muscle and that there was a differential response in cardiac and arterial changes following long term treatment.