Biomedical subjects

I Pithois-Merli

Publications and source records attributed to I Pithois-Merli.

23 records · Page 2Linked to original sources

PubMed1987

Heterogeneity of the atherosclerotic process in systemic hypertension poorly controlled by drug treatment.

A cross-sectional study of 85 patients with poorly controlled treated hypertension was performed to detect, by means of aortic pulse wave velocity measurement and ultrasonic examinations, subclinical alterations of arteries. Pulse wave velocity was related to the product of age and diastolic blood pressure (BP) according to a nomogram obtained from normotensive subjects, and was found inside the nomogram in 37 patients (group I) and outside in 48 (group II). Group II had higher systolic and pulse BP (p less than 0.01), lower diastolic BP (p less than 0.01), higher proportion of cigarette smokers (p less than 0.05) and higher blood glucose levels (p less than 0.02) than group I. In group II a positive correlation existed between blood glucose and pulse wave velocity (p less than 0.01). Group II had a higher frequency of carotid artery stenosis (p less than 0.05) and a trend toward increased frequency of aortic and lower limb atherosclerotic lesions. The results indicate a heterogeneous pattern of arterial alterations in which systolic BP, cigarette smoking and blood glucose level are implicated.

Age Factors↗

PubMed1987

The efficacy of a transdermal formulation of clonidine in mild to moderate hypertension and its effects on the arterial and venous vasculature of the forearm.

We have studied the efficacy of clonidine hydrochloride administered transdermally once a week for 9 to 15 weeks in 12 patients with mild to moderate hypertension. Clonidine reduced both supine and standing blood pressures on average, but only 8 subjects were responders, i.e. had a decrease in supine diastolic blood pressure to below 90 mm Hg or more than 10% from baseline. Supine heart rate was unchanged, but in the responders the orthostatic increase in heart rate was reduced by clonidine from baseline (p less than 0.05). Moreover, in all the patients the change in the orthostatic increase in heart rate was correlated with the change in supine diastolic pressure (p less than 0.05). Brachial artery blood flow, forearm arterial compliance, vascular resistance, and venous tone were not affected by clonidine. Thus, transdermal clonidine reduced blood pressure, probably by a baroreflex-mediated effect, but did not affect the vasculature of the forearm.

Administration, Cutaneous↗

PubMed1987

Large arteries in hypertension: heterogeneous haemodynamic response to beta-adrenoceptor antagonists with and without intrinsic sympathomimetic activity.

1. Hypertension is associated with a distension of the large arteries and consequently a marked reduction in arterial compliance, which does not result merely from the mechanical effects of elevated arterial pressure but also from early functional and/or structural changes in the arterial walls. This suggests that one of the aims of antihypertensive therapy should be to reverse these arterial abnormalities in the hope of protecting the patient from the atherosclerotic complications of hypertension. 2. Studies have been carried out to compare the effects of equieffective antihypertensive doses of pindolol and propranolol on the arterial circulation in patients suffering from essential hypertension. After 3 months therapy pindolol produced a dilatation of the brachial artery with an increase in arterial compliance and blood flow. In contrast, propranolol, despite comparable antihypertensive effects, did not influence brachial artery circulation. 3. These different effects on the arterial circulation presumably reflect the differing pharmacological properties of the two beta-adrenoceptor antagonists and suggest that the intrinsic sympathomimetic activity of pindolol may be responsible for the qualitative differences in the arterial responses to the two drugs. 4. The results reviewed here reveal that even when two drugs of the same class are used to treat patients with essential hypertension the effects of these agents on arterial haemodynamics can vary greatly and are unrelated to the degree of blood pressure lowering. Thus, pindolol, in contrast to propranolol, not only lowers blood pressure but also reverses some of the changes in arterial haemodynamics which are characteristic of hypertensive disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenergic beta-Antagonists↗

PubMed1987

Brachial arterial changes in response to wrist occlusion in normotensive and hypertensive men.

Diameter, blood velocity, and flow of the brachial artery and vascular resistance of the brachial circulation were evaluated with a pulsed Doppler velocimeter before and after wrist occlusion in 8 younger and 8 older normotensive subjects and in 11 younger and 11 older hypertensive patients. Before occlusion, no differences existed between younger and older normotensives. However, in hypertensives, systolic peak velocity was higher in younger than in older hypertensives (P less than 0.001) and correlated to age in the overall patients (r = -0.57, P less than 0.01). Occlusion decreased velocity and flow and increased vascular resistance in all groups, but the change in resistance was not correlated with the base-line resistance. During occlusion, no differences existed between younger and older normotensives. However, in hypertensives mean and systolic peak velocity was higher (P less than 0.01), and vascular resistance was lower (P less than 0.01) in younger than in older patients. In hypertensive patients, during occlusion mean and systolic peak velocity were negatively correlated to age (r = -0.72, P less than 0.001; r = -0.59, P less than 0.01), and vascular resistance was positively related to age (r = +0.66, P less than 0.001). Thus wrist occlusion modified the brachial circulation in normotensive and hypertensive populations but revealed age-related differences only in hypertensive patients, suggesting a combined effect of age and hypertension on the muscle vascular bed.

Adult↗

PubMedDate not supplied

[Hemodynamic effects of labetalol on the humeral artery of the hypertensive patient. A double-blind study versus placebo].

Forearm arterial hemodynamics, including measurements of brachial artery diameter and compliance with pulsed Doppler velocimetry were determined before and after acute administration of labetalol in patients with sustained essential hypertension. Labetalol caused a significant and rapid drop in blood pressure with a decrease in forearm vascular resistance and an increase in brachial blood flow. Brachial artery diameter did not change while arterial compliance significantly increased. The study provided evidence that labetalol caused a shift of the pressure-brachial artery diameter curve toward lower values of blood pressure, indicating a pharmacological effect of alpha and beta blockade on the hypertensive arterial wall.

Brachial Artery↗