Effects of perindopril on ambulatory intra-arterial blood pressure, cardiovascular reflexes and forearm blood flow in essential hypertension

The effects of monotherapy with the angiotensin converting enzyme (ACE) inhibitor perindopril (8 mg once daily) on 24-h ambulatory intra-arterial blood pressure, forearm blood flow, left ventricular mass, vasoactive hormones and cardiovascular reflexes were determined in eight hypertensive patients using a randomized, double blind, placebo-controlled, cross-over protocol. Six weeks of perindopril treatment was associated with a significant reduction of ambulatory blood pressure and a significant increase in forearm blood flow. Whilst the haemodynamic responses to Valsalva's manoeuvre, tilt, isometric forearm exercise and cold pressor testing were unaffected by perindopril, significant augmentation of the bradycardia during facial immersion was seen after chronic therapy. Sino-aortic baroreceptor-heart rate reflex resetting was apparent within 2 h of the first dose; this effect persisted throughout the active treatment period. Withdrawal of treatment was associated with a persisting hypotensive effect and an increase in heart rate which was not accompanied by an increase in plasma catecholamines. We conclude that perindopril, in a dose of 8 mg once daily, was an effective antihypertensive agent. We postulate that chronic therapy was associated with a sustained increase in parasympathetic tone.