Effects of angiotensin antagonism with tasosartan on regional and systemic haemodynamics 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 patients with essential hypertension.


METHODS
Twenty-four patients with moderate hypertension participated in this randomized, double-blind, crossover, placebo-controlled study. Each patient received tasosartan (100 mg/day) or placebo during two periods 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 output, 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 rest.


RESULTS
At rest in the control condition, tasosartan significantly reduced blood pressure although total peripheral resistance, cardiac output and stroke volume as well as forearm and calf vascular resistances were not significantly 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 resistance compared to placebo whereas cardiac output, heart rate, or stroke volume were not affected. Peak workload and oxygen uptake were unaffected by tasosartan.


CONCLUSIONS
The results of this study indicate that antagonism of the AT1 receptor with tasosartan reduces blood pressure at rest and during submaximal exercise but not during maximal exercise. The reduced blood pressure was associated with a reduced total peripheral resistance during submaximal exercise but not at rest in the control condition while cardiac output was unaltered in either condition. Lastly, tasosartan did not impair working capacity as measured from peak workload and oxygen uptake.
Rhéaume
C
C
Hypertension Research Unit, CHUQ, CHUL Pavilion Research Centre, Laval University, Québec, Canada.
Waib
P H
PH
Lacourcière
Y
Y
Cléroux
J
J
D000328:Adult; D057911:Angiotensin Receptor Antagonists; D001794:Blood Pressure / Q000187:drug effects; D004311:Double-Blind Method; D005080:Exercise Test; D005260:Female; D006439:Hemodynamics / Q000187:drug effects* / Q000502:physiology; D006801:Humans; D006973:Hypertension / Q000188:drug therapy* / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D010101:Oxygen Consumption / Q000187:drug effects; D011743:Pyrimidines / Q000494:pharmacology*; D044140:Receptor, Angiotensin, Type 1; D044139:Receptor, Angiotensin, Type 2; D011945:Receptors, Angiotensin / Q000502:physiology; D013777:Tetrazoles / Q000494:pharmacology*; D014655:Vascular Resistance / Q000187:drug effects
D057911:Angiotensin Receptor Antagonists; D011743:Pyrimidines; D044140:Receptor, Angiotensin, Type 1; D044139:Receptor, Angiotensin, Type 2; D011945:Receptors, Angiotensin; D013777:Tetrazoles; C086167:tasosartan