Abstract 2114: Antihypertensive Efficacy And Cerebral Hemodynamic Advantage Of Olmesartan Medoxomil Compared With Amlodipine In Post-stroke Patients
In patients with severe hypertension, chronic heart failure or a history of stroke, the lower limit of autoregulation of cerebral blood flow (CBF) is shifted to higher levels of blood pressure (BP) than those observed in healthy subjects. The effects of anigiotensin II receptor blocker (ARB) on cerebral hemodynamics in humans have not been well elucidated. The antihypertensive efficacy of ARB olmesartan medoxomil (olmesartan) has been shown to compare favourably with that of other antihypertensive agents. We objected:
To compare the effects of olmesartan and amlodipine on 24-h ambulatory blood pressure monitoring (ABPM);
To compare the advantage of CBF of olmesartan and amlodipine on xenon-computed tomography (Xe-CT) after administration of either drug for 8 weeks.
24 hypertensive patients who had an episode of stroke more than 4 weeks previously were recruited for this randomized double-blind study. Olmesartan 10 –20mg (12 patients) or amlodipine 2.5–5mg (12 patients) was administered once daily for 8 weeks. During 24-h monitoring, both drugs caused a decrease in systolic BP of 14 mmHg, and caused a decrease in diastolic BP of 8 mmHg. The Xe-CT results indicated that the increase of CBF of olmesartan was 3.3 ± 1.1 ml/min/100g and that of amlodipine was 0.2 ± 1.3 ml/min/100g. Thus, despite the reduction in BP, CBF was significantly increased in olmesartan group compared with amlodipine group. We consider the use of olmesartan is advantageous for hypertensive patients with a history of stroke in whom autoregulation of CBF is potentially impaired.