Haemodynamic effects of eprosartan and valsartan in hypertensive patients during isometric and mental stress

OBJECTIVE: To assess the effects of eprosartan and valsartan on the haemodynamics of forearm circulation in hypertensives undergoing isometric and mental stress. DESIGN AND METHODS: Thirty-six patients with essential stable hypertension underwent haemodynamic evaluations on the left arm: humeral flux and calibre by means of colour Doppler ultrasound, microcirculatory flux on the third finger of left hand by means of laser Doppler flowmetry, blood pressure and heart rate monitor. District resistance was calculated as the ratio between mean arterial pressure and blood flow, and microcirculatory conductance was calculated as the ratio between flux and the mean pressure. The evaluations were performed at rest, during handgrip and during mental stress. Patients were randomized to receive eprosartan (600 mg) or valsartan (160 mg); tests were repeated after 15 days of therapy. RESULTS: Both treatments reduced blood pressure (P<0.05) and peripheral resistance during tests. Eprosartan obtained a greater reduction in resistance during handgrip than valsartan. Laser Doppler flowmetry showed a significant decrease of flux only with mental stress. Laser Doppler flowmetry showed a reduction in conductance during both tests--this reduction was smaller with eprosartan during handgrip. None of the molecules affected the conductance during mental stress. While both were able to reduce microcirculatory decrease in conductance; in particular, eprosartan controlled this drop during handgrip better than valsartan. CONCLUSIONS: Angiotensin II receptor type 1 inhibition exerts protective effects during adrenergic and noradrenergic stress in hypertensives. Eprosartan is more efficacious than valsartan in controlling noradrenergic effects.