Effects of angiotensin antagonism with tasosartan on regional and systemichaemodynamics in hypertensive patients

Objective Evaluate the effects of 2 weeks of treatment with tasosartan (1) on cardiac function at rest and during submaximal exercise, (2) on exercise peak oxygen uptake, and (3) on regional haemodynamics at rest in a control condition and during the recovery period of submaximal exercise in patient s with essential hypertension. Design end methods Twenty-four patients with moderate hypertension particip ated in this randomized, double-blind, crossover, placebo-controlled study. Each patient received tasosartan (100 mg/day) or placebo during two period s of 2 weeks separated by 2 weeks of washout. Ambulatory blood pressure was assessed at the end of each period. Blood pressure, heart rate, cardiac ou tput, stroke volume, total peripheral resistance were measured at rest and during submaximal exercise at the same end points. Regional blood flow and vascular resistance were additionally assessed in the forearm and calf at r est. Results At rest in the control condition, tasosartan significantly reduced blood pressure although total peripheral resistance, cardiac output and str oke volume as well as forearm and calf vascular resistances were not signif icantly affected compared to placebo. During submaximal exercise and during the recovery period after submaximal exercise, the reduced blood pressure found with tasosartan was associated with a reduced total peripheral resist ance compared to placebo whereas cardiac output, heart rate, or stroke volu me were not affected, Peak workload and oxygen uptake were unaffected by ta sosartan. Conclusions The results of this study indicate that antagonism of the AT(1) receptor with tasosartan reduces blood pressure at rest and during submaxi mal exercise but not during maximal exercise. The reduced blood pressure wa s associated with a reduced total peripheral resistance during submaximal e xercise but not at rest in the control condition while cardiac output was u naltered in either condition. Lastly, tasosartan did not impair working cap acity as measured from peak workload and oxygen uptake. J Hypertens 1998, 1 6:2085-2089 (C) 1998 Lippincott Williams & Wilkins.