THE INFLUENCE OF CHRONIC TREATMENT WITH BETA-BLOCKADE AND ANGIOTENSIN-CONVERTING ENZYME-INHIBITION ON THE PERIPHERAL-BLOOD FLOW IN HYPERTENSIVE PATIENTS WITH AND WITHOUT CONCOMITANT INTERMITTENT CLAUDICATION - A COMPARATIVE CROSS-OVER TRIAL

In a comparative cross-over trial we examined the influence of the betablocker bisoprolol and the ACE-inhibitor lisinopril on the peripheral blood flow of 2 groups of hypertensive patients with and without concomitant intermittent claudication. In 11 patients with hypertension without peripheral arterial obstructive disease and 11 patients with hypertension and claudication we assessed the blood pressure, leg blood flow, vascular resistance, walking distance, transcutaneous oxygen consumption and Laser-Doppler flow after treatment of one month with 10 mg bisoprolol once daily or 20 mg lisinopril once daily. The walking distance of patients with claudication improved in all patients while participating in an exercise program. For both treatment groups this improvement was significant (p <0.05) compared to baseline, from 264 m at baseline to 313 m with bisoprolol and to 400 m with lisinopril. The difference was not significant between the both drugs. In patients without peripheral vascular obstructive disease we found a significant (p <0.05) reduction in blood flow for both drugs. The peripheral blood flow parameters of 38 legs showed no statistical significant effect of bisoprolol nor lisinopril on the local vascular resistance at rest, after occlusion or after exercise

THE INFLUENCE OF CHRONIC TREATMENT WITH BETA-BLOCKADE AND ANGIOTENSIN-CONVERTING ENZYME-INHIBITION ON THE PERIPHERAL-BLOOD FLOW IN HYPERTENSIVE PATIENTS WITH AND WITHOUT CONCOMITANT INTERMITTENT CLAUDICATION - A COMPARATIVE CROSS-OVER TRIAL

In a comparative cross-over trial we examined the influence of the betablocker bisoprolol and the ACE-inhibitor lisinopril on the peripheral blood flow of 2 groups of hypertensive patients with and without concomitant intermittent claudication. In 11 patients with hypertension without peripheral arterial obstructive disease and 11 patients with hypertension and claudication we assessed the blood pressure, leg blood flow, vascular resistance, walking distance, transcutaneous oxygen consumption and Laser-Doppler flow after treatment of one month with 10 mg bisoprolol once daily or 20 mg lisinopril once daily. The walking distance of patients with claudication improved in all patients while participating in an exercise program. For both treatment groups this improvement was significant (p <0.05) compared to baseline, from 264 m at baseline to 313 m with bisoprolol and to 400 m with lisinopril. The difference was not significant between the both drugs. In patients without peripheral vascular obstructive disease we found a significant (p <0.05) reduction in blood flow for both drugs. The peripheral blood flow parameters of 38 legs showed no statistical significant effect of bisoprolol nor lisinopril on the local vascular resistance at rest, after occlusion or after exercise

Arteriolar constriction in mild-to-moderate essential hypertension:An old concept requiring reconsideration?

Objective To investigate differences between in-vivo properties of a vascular bed in hypertensive patients and normotensive controls, Design Despite the controversy about the origin of essential hypertension and its accompanying vascular changes, it is generally assumed that the characteristic increase in peripheral resistance when hypertension progresses is caused by arteriolar constriction. Yet, there is little experimental evidence that this assumption generally holds in vivo. Methods A non-invasive technique was used for studying properties of the complete vascular bed of an upper arm segment under an occluding cuff in 23 previously untreated hypertensive patients and their matched normotensive controls. The method used the segment's electrical impedance to assess the volumes of extravascular fluid and of arterial and venous blood under varying arterial transmural pressures. Results Compared with that of matched normotensive controls, the compliance of the large arteries of the vascular bed was on average 50.9% lower (P <0.001) in the hypertensive patients, The compliance of the complete arterial bed at the operating blood pressure level was also lower (40.0%, P <0.01), but appeared to be significantly higher (45.9%, P <0.05) at the normotensive blood pressure level, On the venous side, the patients had a higher blood volume (60.0%, P <0.01) and an increased myogenic response (68.5%, P <0.05). Conclusions The increase in vascular resistance in the hypertensive patients is due primarily to changes in the large and small vessels of the arterial bed, We found no evidence for a generally increased arteriolar constriction