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Showing papers by "Stéphane Laurent published in 1988"


Journal ArticleDOI
TL;DR: Blood pressure, forearm arterial hemodynamics (with a pulsed Doppler flowmeter), and echocardiographic parameters were studied in 16 patients with sustained essential hypertension before and 3 months after administration of the converting enzyme inhibitor perindopril.
Abstract: Blood pressure, forearm arterial hemodynamics (with a pulsed Doppler flowmeter), and echocardiographic parameters were studied in 16 patients with sustained essential hypertension before and 3 months after administration of the converting enzyme inhibitor perindopril. In a single-blind study versus placebo, it was shown that perindopril significantly reduced blood pressure (p less than 0.01), whereas there was an increase in brachial blood flow (p less than 0.01) because of a simultaneous increase in blood flow velocity (p less than 0.01) and arterial diameter (p less than 0.01). During a 5-minute period of wrist occlusion, blood flow velocity was reduced to a greater extent with perindopril than with placebo (p less than 0.001), whereas corresponding reductions in arterial diameter were equivalent, indicating that the increase in diameter after perindopril could not be explained simply on the basis of flow-dependent dilatation. During active treatment, brachial artery compliance increased (p less than 0.01) and pulse wave velocity decreased (p less than 0.01), whereas there was no change in the tangential tension of the arterial wall, defined as the product of mean arterial pressure and arterial diameter. Four weeks after treatment was stopped, blood pressure and forearm arterial hemodynamics returned toward baseline values. Cardiac mass was significantly decreased after perindopril (p less than 0.01) and remained decreased 4 weeks after cessation of treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

223 citations


Journal ArticleDOI
TL;DR: It is suggested that, in patients with essential hypertension, changes of sodium intake in diet or administration of diuretics, or both, affect the status of large arteries independently of blood pressure changes.

37 citations


Journal ArticleDOI
TL;DR: It is suggested that, in patients with essential hypertension, changes of sodium intake in diet or administration of diuretics, or both, affect the status of large arteries independently of blood pressure changes.

14 citations


Journal ArticleDOI
TL;DR: The results suggest that a stereoselectivity exists for the peripheral and central hypotensive effects of the nicardipine isomers, which was shown to be 3-8 times as potent as the (-) isomer in reducing blood pressure in all the experiments.

12 citations


Journal ArticleDOI
TL;DR: The results suggest that velocity-dependent vasodilation of the brachial artery is not impaired in essential hypertension, and variation in the diameter of a large artery in humans is demonstrated.
Abstract: Brachial artery haemodynamics including brachial artery diameter and local blood flow velocity were studied in 10 normotensive subjects and 10 age-matched hypertensive patients. A bidimensional pulsed Doppler system was used at rest, during a 2-min period of distal circulatory occlusion and during reactive hyperaemia. The kinetics of changes in blood flow velocity and brachial artery diameter were determined during successive and reproducible manoeuvres. The two parameters decreased significantly during distal artery occlusion in both groups. During reactive hyperaemia, blood velocity reached similar maximal values in both groups and brachial artery diameter increased significantly in both normotensives and hypertensives. Changes in the brachial artery diameter during reactive hyperaemia were positively and significantly correlated to changes in blood flow velocity recorded at the same level. No significant difference was found between normotensives and hypertensives. This study has provided a demonstration of velocity-dependent variations in the diameter of a large artery in humans; the results suggest that velocity-dependent vasodilation of the brachial artery is not impaired in essential hypertension.

11 citations


Journal ArticleDOI
TL;DR: The results indicate that dihydropyridines may centrally modulate baroreceptor reflex sensitivity in SHR and suggest that the inhibitory effect of the calcium agonist BAY k 8644 on baroreceptors reflex sensitivity may have been mediated by an enhanced release of acetylcholine.
Abstract: The effects of two dihydropyridine derivatives, the calcium channel agonist BAY k 8644 or the antagonist PN 200-110, on the central nervous components of the baroreceptor reflex control of heart rate during activation of baroreceptors by phenylephrine (2 micrograms i.v.) were studied in pentobarbital-anesthetized normotensive (Wistar) rats and spontaneously hypertensive rats (SHR). To rule out an effect on peripheral vessels or on the sinoauricular node (or on both), BAY k 8644 and PN 200-110 were administered intracerebroventricularly (i.c.v.) at doses that did not change blood pressure. Baroreceptor reflex sensitivity was calculated as the slope of the relationship between systolic arterial pressure and heart period. Baroreceptor reflex sensitivity increased with time following the onset of anesthesia. In SHR, injection of BAY k 8644 (3 micrograms/kg i.c.v.) suppressed the time-dependent increase in baroreceptor reflex sensitivity. The inhibitory effect of BAY k 8644 (3 micrograms/kg i.c.v.) on the time-dependent increase in baroreceptor reflex sensitivity was suppressed by pretreatment with PN 200-110 (0.6 microgram/kg i.c.v.) but not with the solvent, indicating that the central effect of BAY k 8644 occurred at the level of specific dihydropyridine binding sites. In addition, the inhibitory effect of BAY k 8644 (3 micrograms/kg i.c.v.) on the time-dependent increase in baroreceptor reflex sensitivity was suppressed by pretreatment with the muscarinic antagonist atropine methylnitrate (80 micrograms/kg i.c.v.) but not with the solvent. In normotensive rats, the time-dependent increase in baroreceptor reflex sensitivity was not significantly altered by BAY k 8644 (3 micrograms/kg i.c.v.).(ABSTRACT TRUNCATED AT 250 WORDS)

10 citations


Journal ArticleDOI
TL;DR: The results suggest that the dihydropyridine calcium channel antagonist, PN 200-110, may act centrally and stereoselectively at the level of the di hydrocarbon receptor sites involved in the control of blood pressure in spontaneously hypertensive rats.

8 citations


Journal ArticleDOI
01 Oct 1988-Stroke
TL;DR: This work reviews carotid artery hemodynamics in hypertensive men, with particular reference to common carotids diameter and blood flow, and emphasizes the changes in artery diameter and compliance implied by antihypertensive therapy.
Abstract: We review carotid artery hemodynamics in hypertensive men, with particular reference to common carotid artery diameter and blood flow, and emphasize the changes in artery diameter and compliance implied by antihypertensive therapy.

8 citations


Journal ArticleDOI
TL;DR: Changes in hemodynamic parameters following 50-degree head up tilt were studied and suggest an abnormality in the autonomic nervous control in patients with borderline hypertension, possibly mediated by cardiopulmonary mechanoreceptors in the low pressure system.

5 citations


Journal ArticleDOI
TL;DR: It was demonstrated that renal ischemia was absent in young patients with borderline hypertension and both CO and RBF were significantly increased, whereas the RBF/CO ratio remained within the normal range.

5 citations


Journal Article
TL;DR: It is shown that BP Monitoring correlates more strongly than clinic or casual BP with indices of target organ damage, especially for the systolic BP measured in the Day Time by the ambulatory method.
Abstract: Cardiovascular morbidity and mortality of hypertensive patients is mainly related to lesions of large arteries. Arterial distensibility estimated by carotid-femoral pulse wave velocity (PWV) was evaluated in 22 patients with sustained essential hypertension, together with three different methods of blood pressure (BP) measurement: mercury sphygmomanometer, semi-automatic BP recording using the Dinamap apparatus and 24 H ambulatory BP monitoring using the Spacelabs Monitor (5200). Table shows that, while PWV was not correlated with BP measured by mercury sphygmomanometer, it was strongly and positively correlated with BP measured by the other procedures. The best correlation coefficient was noted for the systolic BP measured in the Day Time (7 h-22 h) by the ambulatory method. This study shows that BP Monitoring correlates more strongly than clinic or casual BP with indices of target organ damage. (Table: see text).

Journal Article
TL;DR: It is demonstrated that acute treatment with non selective beta-blockers with or without sympathomimetic intrinsic activity does not prevent haemodynamic modifications induced by cigarette smoking.
Abstract: In mild hypertension, a betablocker treatment could reduce cardiovascular events. But in smoking men the benefit disappears and this interaction is unexplained. In 6 healthy non smoking men, we studied the effects of acute oral administration of propranolol (80 mg) pindolol (15 mg) and placebo after cigarette smoking (CS) (two cigarettes within 10 minutes). In a double blind cross over randomized study, arterial pressure and heart rate (HR) were recorded within 20 minutes after CS. Brachial artery diameter (D), Local vascular Resistance (RL), Local arterial Compliance (CL) and pulse wave velocity (VOP) were determined non invasively (using a pulsed doppler system) before and 20 mn after CS. Under placebo, mean arterial pressure (PAM), HR and RL increased significantly after CS (+9.2 +/- 3 mmHg, +4.5 +/- 3 b/mn and +36 +/- 14 per cent, respectively). These modifications were not different after propranolol, pindolol or placebo (ANOVA). Arterial distensibility (CL) was decreased after CS and this alteration was not prevented by beta-blockers. Brachial artery diameter was not modified after CS. Our results demonstrate that acute treatment with non selective beta-blockers with or without sympathomimetic intrinsic activity does not prevent haemodynamic modifications induced by cigarette smoking.

Journal Article
TL;DR: Arterial hypertension is linked with left ventricular hypertrophy which is increased when pulsed pressure is enhanced which could give evidence of importance of pulsatory work in cardiac consequence of hypertension.
Abstract: UNLABELLED We measured systolic, diastolic, mean (MAP) and pulsed (PP) arterial pressures (Dinamap 845 XT), carotid femoral pulse wave velocity (PWV) and cardiac parameters (echocardiography) to evaluate myocardiac mass and indexed cardiac mass to body surface area (IM) in 47 subjects (11 normotensives and 36 with sustained essential hypertension). Hypertensives were allocated between two groups with same age, weight and height, same mean arterial pressure (119.8 +/- 9.1 mmHg, 119.7 +/- 11.9 mmHg, NS) and PWV (11.90 +/- 2.20 m/s, 12.51 +/- 1.83 m/s, NS): group I (22 subjects) with pulsed pressure less than 60 mmHg, group II (14 subjects) with pulsed pressure greater than or equal to 60 mmHg. (Table: see text). Newman-Keuls between group I and group II: p less than 0.01 for cardiac mass and IM, p less than 0.001 for PP. Cardiac mass (p less than 0.01) and indexed mass to body surface area (p less than 0.01) were greater in group II (with pp greater than or equal to 60 mmHg) than in group I. CONCLUSION arterial hypertension is linked with left ventricular hypertrophy which is increased when pulsed pressure is enhanced. This fact could give evidence of importance of pulsatory work in cardiac consequence of hypertension.