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Epidemiologic studies evaluating arterial pulse wave velocity together with blood pressure indicate that: (1) salt intake has an independent effect on arteriolar tone and arterial wall properties, with the former indirectly and the latter directly contributing to increased arterial stiffness with age; and (2) normotensive adult subjects who follow a low sodium diet have reduced arterial stiffness and this effect is independent of blood pressure. Conversely, in elderly persons with isolated systolic hypertension, isotonic saline infusion causes a predominant increase in systolic pressure due to an increase in the stiffness of the arterial wall. The diuretic indapamide produces a decrease in blood pressure without significant change in brachial artery diameter. The result indicates a shift of the pressure-diameter curve, reflecting for the first time in humans a pharmacologic effect of the drug on arterial vessel. Furthermore, diuretic drugs may increase arterial distensibility and compliance in hypertensive patients, but this effect seems to be more pronounced in older than in younger subjects. In the latter, either activation of the sympathetic nervous system or potassium depletion, or both, might counteract the improvement in arterial distensibility caused by blood pressure reduction and sodium depletion. Based on epidemiologic, clinical, and pharmacologic studies, this critical review suggests 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.

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).

A pilot study was performed in hypertensive patients (a) to investigate the duration of blood pressure reduction produced by the new beta blocker bisoprolol (10 mg o.d.) after cessation of a 4 week treatment using non-invasive 24 hour ambulatory blood pressure measurements, (b) to study the effects of the drug on large arteries using non-invasive brachio-radial pulse wave velocity and aortic abdominal diameter measurements 3 hours after the last dose of a 4 week treatment. In comparison with the results obtained before treatment a significant reduction of blood pressure and heart rate was observed up to the 40th hour after treatment was terminated. The finding may be relevant for further evaluation of withdrawal phenomena produced by beta-blocking agents. The antihypertensive effect of bisoprolol was associated with significant decreases in brachio-radial pulse wave velocity (from 10.4 +/- 0.4 to 8.6 +/- 0.4 m s-1) and in aortic abdominal diameter (from 18.2 +/- 1.0 to 17.5 +/- 1.3 mm) indicating an increase in arterial distensibility. Further studies are needed to substantiate these observations and to reveal their mechanisms of action.

Forearm venous tone (FVT), carotido-femoral pulse wave velocity (PWV), and left ventricular end diastolic diameter (LVD), left ventricular posterior wall thickness (LVPWT), myocardiac mass (MM), measured by echography were evaluated on 25 subjects with sustained essential hypertension and 30 normotensive subjects with same age and same sex. For the overall population, FVT is positively correlated with LVD (r = 0.45, p less than 0.001), with LVPWT (r = 0.37, p less than 0.01) and with MM (r = 0.55, p less than 0.001). PWV is not correlated with LVD but is positively correlated with LVPWT (r = 0.48, p less than 0.001) and with MM (r = 0.40, p less than 0.01). Stroke volume is positively correlated with FVT (r = 0.42, p less than 0.01), but not with PWV. This study shows that in a population of normals and sustained essential hypertensive subjects: i) indexes of venous compliance are correlated with myocardial thickness, myocardiac mass, left ventricular diameter and stroke volume, while ii) indexes of arterial compliance are only correlated with myocardial thickness. Thus, the modifications of arterial and venous compliance observed in sustained essential hypertension influence cardiac structure and function.

An exaggerated reflex response of forearm resistance vessels following stimulation of cardiac mechanoreceptors has been observed in human hypertension. In the present study we analyze the possibility that such an increased response also involves the large brachial artery. For that purpose, the influence of leg elevation in subjects in a supine position on brachial artery diameter and blood flow velocity was studied in 12 healthy, normal males and 17 males of the same age with sustained essential hypertension. Brachial artery diameter and blood flow velocity were measured using a two-dimensional pulsed Doppler velocimeter, with subjects in a supine horizontal position, after passive elevation of the legs and again in a supine horizontal position. Blood pressure and heart rate remained unchanged throughout the study. Elevation of the legs induced an immediate increase in brachial artery diameter (P less than 0.001) and blood flow velocity (P less than 0.001) in both normal subjects and hypertensive patients. The maximal increase in these two parameters was similar in the two groups. In normal subjects, the increases were short-lived, with values returning to baseline levels even when leg elevation was maintained. In hypertensive patients, the increases persisted throughout the period of leg elevation, and brachial artery diameter remained significantly increased in comparison with normal subjects (P less than 0.01). This study provides evidence that loading cardiac mechanoreceptors causes a large dilation of the conduit arteries which is long-lasting in essential hypertensives and short-lived in normal subjects.

In this study, we have attempted to determine the link between the occasional measurement of the blood pressure with an Hg sphygmomanometer and the ambulatory pressure, considering different recording periods during the nyctemer. The mean values of the period 8-10 A.M. and more generally of the diurnal period (7 am-10 pm) are close to the values occasionally observed, contrary to the night values and the values of the entire 24 hours. The heart frequency is always well correlated to the mean ambulatory frequency, for the entire period studied. The systolic and mean arterial pressure are also well correlated. On the contrary, there is no meaning when the diurnal period (7 am-10 pm) is reduced to the period of diurnal activity (7 am-7 pm). There is a very strong correlation between the values of the systolic, diastolic, and mean pressures observed during 24 hours and the morning period (8-10 am), giving the impression that this period could be a good reflection of the ambulatory blood pressure of the 24 h.

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.

The introduction in the treatment of arterial hypertension of angiotensin-converting enzyme inhibitors and calcium inhibitors, as well as the results of extensive multicentric therapeutic trials, suggest that the prescription of antihypertensive drugs will be profoundly altered in the forthcoming years. The "step by step" approach will be abandoned, and each patient will receive one or two drugs chosen for being the most selective and most suitable for his case. These more personalized long-term treatments will be better tolerated, and the greater patient's compliance will make them more effective drugs to the underlying pathology (smoking habits, blood lipid disorders, early arterial lesions) the antihypertensive treatment will have a greater reducing effect on cardiovascular morbidity and mortality.

The hemodynamic changes caused by ketanserin, an anti-hypertensive agent with S2-serotonergic receptor and alpha 1-adrenoceptor blocking properties, are reviewed in patients with essential hypertension. The hemodynamic profile associates a decrease in total peripheral resistance, an unchanged cardiac output, and a modest reflex cardiac stimulation. Whether the drug reverses the other hemodynamic abnormalities of essential hypertension, such as reduced arterial and venous compliances and increased cardiac mass, remains largely unknown. Evaluation of the changes in arterial and venous systems will be important in the view that the pharmacological profile of ketanserin could be involved in the modifications of the arterial wall observed in hypertension and atherosclerosis.