Showing papers by "Giuseppe Mancia published in 1993"

Prognostic value of 24-hour blood pressure variability.

Abstract: Objectives: Evaluation of the prognostic value of 24-h blood pressure averages and 24-h blood pressure variability. Design: After an initial thorough clinical and laboratory evaluation which included 24-h continuous ambulatory blood pressure monitoring, a group of hypertensive patients were re-examined after an average of 7.4 years. End-organ damage at the follow-up visit was related to different measures of blood pressure levels and variability obtained at the initial or the follow-up visit or both

1993 Guidelines for the management of mild hypertension: MEMORANDUM from a World Health Organization/International Society of Hypertension meeting

Abstract: Patients with hypertension, even those with mild elevation of blood pressure, are at increased risk of cardiovascular disease, whether or not symptoms are present. In most countries, as many as 15% to 25% of the adult population are found at screening to have raised blood pressure; about two thirds of them have mild elevation of blood pressure. However, blood pressure is not persistently raised in all, and not all need to be treated with antihypertensive drugs. The present guidelines for the management of hypertension concentrate on mild hypertension, as this condition often presents a diagnostic and therapeutic problem, and evidence for benefit in treating more severe hypertension is clear. Emphasis is also placed on systolic blood pressure as a criterion for decision making and on hypertension in the elderly, another condition in which careful judgment is necessary. Information is provided on useful methods for diagnostic evaluation and the assessment of cardiovascular risk. Additional information is provided on nondrug measures as well as drug treatment of hypertension and on the correction of other major risk factors for cardiovascular disease (see Table 1). In preparing these guidelines, the World Health Organization/International Society of Hypertension (WHO/ISH) Subcommittee has been keenly aware that marked differences exist among individual patients with similar levels of hypertension and that these differences have important implications for decisions about treatment. Hypertensive patients differ with respect to age, blood pressure elevation, organ damage, and concomitant risk factors and diseases, and they live in societies in which cardiovascular risk and economic resources also differ widely. Accordingly, guidelines should not be conceived as rigid constraints to the practicing doctor's

Autonomic modulation of the cardiovascular system during sleep.

Abstract: There are several reasons for the growth of interest in the effect of sleep on the cardiovascular system. Because about one third of human life is spent sleeping, a description of the cardiovascular changes accompanying sleep is necessary for a thorough definition of the hemodynamic profile of everyday life. A more thorough understanding of the cardiac, vascular, and humoral effects of sleep may clarify why some cardiovascular events occur less often, and others more often, during sleep than during wakefulness1,2. Because it arises from events within the central nervous system,3 mammalian sleep serves as a model for studying . . .

Ambulatory blood pressure monitoring use in hypertension research and clinical practice

Abstract: In his article on blood pressure measurement by sphygmomanometry published in 1897 in the Gazzetta Medica di Torino,' Riva Rocci wrote the following: \"Blood pressure is acted upon, in a temporary but pronounced fashion, by the state of 'psychic' excitation of the patient. It is enough that the patient is spoken to, that he is invited to read, that he is even looked at suddenly, or that a sudden and even far noise strikes him (e.g., a carriage passing by in the outside street) that his blood pressure raises, and not at all to the same extent in all patients. This emotional reaction may be useful in psychiatry, but in other disciplines these blood pressure rises represent an inconvenience, and it is therefore necessary for the patient to be put in an environment as quiet as possible. . . . Furthermore, because even the application of the instrument causes a temporary blood pressure rise, it is necessary to take not only one but several consecutive blood pressures spaced by 3or 5-minute intervals until a constant value is measured. This value, however, is not always the minimal value.. . . It should not be necessary to add that it will not be proper to compare data unless obtained in identical conditions or environment, position, time of day, distance from meals, wakefulness, etc. This remark is certainly superfluous for the investigators, but it may be useful to practitioners whose hurry may in this case result in a waste rather than a gain of time.\

1993 Guidelines for the Management of Mild Hypertension: Memorandum from a WHO/ISH Meeting

Abstract: The present guidelines were prepared by the Guidelines Sub-Committee* of the WHO/ISH Mild Hypertension Liaison Committee. They represent the third revision of the WHO/ISH guidelines and were finalized after presentation and discussion at the 6th WHO/ISH Meeting on Mild Hypertension held in Chantilly, France on 28-31 March 1993. The previous WHO/ISH guidelines were published in Bull WHO 1989; 67: 493-498, and J Hypertens 1989; 7: 689-693. (Hypertens Res 1993; 16: 149-161)

Isobaric compliance of the radial artery is increased in patients with essential hypertension.

Abstract: Objectives:Hypertension is known to decrease arterial elasticity and systemic compliance. However, the arterial tree is not a homogeneous system, and whether a distal medium-sized artery such as the radial artery behaves like proximal arteries has not been determined. The aims of the present study w

Evaluating sympathetic activity in human hypertension.

Abstract: AIM: To review the use of plasma norepinephrine to evaluate sympathetic activity in humans, and to discuss the improvement in assessment of human sympathetic activity brought about by the norepinephrine spillover method and by microneurography. METHOD: Literature survey. RESULTS: These methods have limitations, and an accurate assessment of sympathetic cardiovascular control should not be limited to an investigation of sympathetic nerve firing or norepinephrine secretion but include cardiac and vascular responses. These responses can be assessed by traditional pharmacological means (for example, a reduction in vascular resistance induced by alpha-adrenergic blockade) or by a variety of approaches aimed at examining sympathetic cardiovascular modulation in a more integrated fashion, such as the recently developed power spectrum analysis of blood pressure and heart rate. CONCLUSION: The sensitivity and specificity of all these methods is still under investigation, but in almost every case an increase in sympathetic cardiovascular influence has been reported to occur in hypertension, indicating that sympathetic activation has a pathogenic effect on this condition.

Vascular wall thickness in hypertension: the Perindopril Regression of Vascular Thickening European Community Trial (PROTECT).

Abstract: A high prevalence of increased intima/media thickness of the arterial wall has been documented in hypertension. These alterations in vascular wall structure may be potent determinants for the promotion of the development of atherosclerosis. Direct histologic data from animal models of hypertension, and indirect data from hypertensive patients, have demonstrated a marked regression of increased intima/media thickness by angiotensinconverting enzyme (ACE) inhibition. long-term effects of ACE inhibition on structural wall changes in humans have not been examined. Therefore, a multicenter, randomized, double-blind European trial was designed to compare the effects of the ACE inhibitor perindopril and the diuretic hydrochlorothiazide in slowing or reversing progression of increased intima/media thickness of carotid and femoral arteries in hypertensive patients. A total of 800 patients at 17 clinical centers in 7 European countries, aged 35-65 years, with hypertension and ultrasonographically proven intima/media thickness ~0.8 mm of the common carotid artery will be randomly assigned to receive in a doubleblind fashion either perindopril or hydrochlorothiazide and will be followed for 24 months. High resolution duplex sonography will be used to quantify intima/media thickness at baseline and twice a year during follow-up. A change of 0.1 mm of intima/media thickness from baseline is considered to be detectable, and the standard deviations of the changes from baseline are expected not to be higher than 0.2 mm. The primary endpoint of the study is the comparison of changes in intima/media thickness of the common carotid artery. Secondary endpoints include comparison of the effectiveness of the two treatments on left ventricular mass, posteriorwall thickness, intraventricular septal thickness, left ventricular end-diastolic diameter, and comparisonof the 2 treatments on ultrasonographitally determined thickness of the intima/media complex of the common femoral artery. Further analyses will assess the relation between intima/ media thickness changes and the changes of blood pressure, heart rate, low and high density lipoprotein cholesterol, triglycerides, and glucose. The study is designed to assess the impact of antihypertensive therapy on early pathological vascular wall changes and to clarify whether this is due to a drug-specific action or only dependent on the blood pressure lowering effect. (Am J Cardioll995; 7650E64E)

Ambulatory blood pressure monitoring in hypertension

Abstract: Ambulatory blood pressure monitoring generates a greater interest among investigators and clinicians because of its potential to 1) study the mechanisms involved in cardiovascular control in daily life (particularly if monitoring is performed on a beat-to-beat basis) and 2) improve the diagnosis of hypertension, the estimate of the patient's risk and the assessment of the efficacy of antihypertensive treatment. This paper will discuss the evidence pros and cons the latter indications of this approach. It will be shown that 24 hour blood pressure values correlate more closely than clinic blood pressure with various measures of the end organ damage of hypertension, suggesting that it may reflect better than traditional blood pressure measurements the cardio-vascular consequences of this condition. Wider use of ambulatory blood pressure monitoring in the medical practice, however, must await a more clear demonstration of its prognostic importance, by longitudinal studies based on cardiovascular morbidity and...

Vasovagal syncope with bradycardia during lower body negative pressure in a heart transplant recipient

Abstract: Vasovagal syncope has been ascribed to the vagal excitation and the sympathetic inhibition induced reflexly by mechanical stimulation of receptors in the ventricles. In this case report we describe a vasovagal syncope with bradycardia triggered by a reduction in venous return obtained via mild lower body negative pressure, in a patient with cardiac denervation due to heart transplantation. This suggests that the mechanisms involved in this phenomenon may not exclusively depend on a reflex originating from ventricular receptors. It also suggests that non-neural factors may be involved in the genesis of the bradycardia.

Vascular effects of lacidipine: a review of animal and human data.

Abstract: Aim To compare the vascular effects of lacidipine with those of other calcium antagonists. Methods A review of published studies. Results Experimental studies have shown that for a similar fall in blood pressure, lacidipine increased cardiac contractility while verapamil decreased cardiac contractility. In the rat aorta, the dose of lacidipine required to reduce a calcium-induced contraction by 50% was lower than that of all other calcium antagonists tested except nisoldipine. In human studies, especially, there are inherent limitations in the techniques available to measure regional blood flows under physiological conditions, making it difficult to compare the effects of different antihypertensive drugs. A recent study showed that renal blood flow was increased by lacidipine without any reduction in renal function. As in animals, vital organ perfusion was either preserved or increased. Further, maximal coronary vasodilation was associated with lower coronary resistance values during lacidipine treatment compared with pretreatment values. Another lacidipine study showed increased brachial artery compliance, while a study on the radial artery showed that lacidipine increased the compliance of this artery also. Conclusions Lacidipine has vascular selectivity. Although regional blood flows are difficult to measure, due to inherent limitations in the techniques available, the evidence suggests that lacidipine produces vasodilation in essential hypertensive subjects while maintaining or even increasing vital organ perfusion. This appears to be due to a regression of the structural changes that characterize hypertension.

Spontaneous variability of regional haemodynamics in unanaesthetized rats

Abstract: AIM To study the spontaneous variability in regional haemodynamics. METHODS Twenty normotensive Wistar-Kyoto rats were chronically instrumented with an arterial catheter and with pulsed Doppler flowmeters on the distal aorta, and the superior mesenteric and left renal arteries. After surgical recovery, the rats were monitored in unrestrained conditions. The recorded signals were analysed beat-to-beat to obtain means and coefficients of variation for mean arterial pressure, heart rate, regional blood flow velocity (consecutive 0.8-s periods) and indices of regional vascular resistance (0.8-s ratio of mean arterial pressure to mean blood flow velocity). RESULTS Muscle and splanchnic blood flow velocities were markedly variable, with coefficients of variation of 12.8 +/- 0.8 and 12.2 +/- 1.7% (means +/- SEM), respectively, about twice as large as the coefficient of variation for mean arterial pressure (6.2 +/- 0.3%). The renal blood flow velocity was slightly less variable than the muscle and splanchnic blood flow velocities, with a coefficient of variation of 10.4 +/- 0.8%, but still markedly and significantly more variable than systemic arterial pressure. A contingency analysis of paired variations in any two given parameters (arterial blood pressure, heart rate, blood flow velocities and indices of vascular resistance) showed a concordant pattern, the only exception being a distinctly discordant trend for the covariations in muscle and splanchnic blood flow velocities. CONCLUSIONS Regional blood flow velocity and vascular resistance have a larger degree of spontaneous variability than systemic arterial pressure. Renal blood flow velocity is also highly variable, suggesting that short-term stimuli that affect the renal blood vessels are not countered by autoregulation to any great degree. We conclude that while central factors may drive concordant regional haemodynamic variations, some opposing changes in regional blood flow velocity may cancel each other out, thereby reducing the variability in systemic blood pressure.

[Hypertension, left ventricular hypertrophy and heart failure].

Abstract: Epidemiological and clinical studies carried out over the past 30 years have unequivocally shown that cardiac hypertrophy is frequently associated with high blood pressure values adversely affecting, from a pathophysiological and prognostic view point, the clinical evolution of the hypertensive disease. From a pathophysiological view point, it has been reported that a pathologic increase in cardiac wall thickness not only impairs diastolic function, coronary circulation and reflex control of circulation exerted by cardiopulmonary volume receptors, but also enhances cardiac work and myocardial oxygen consumption. From a clinical view point, cardiac hypertrophy has been shown to increase the risk of occurrence of cardiac arrhythmias, myocardial infarction, heart failure and sudden cardiac death. Antihypertensive drugs, such as ACE-inhibitors, calcium antagonists and alpha and beta-blocking agents, by reducing high blood pressure values and concomitantly by favouring the regression of the echo- and electrocardiographic signs of cardiac hypertrophy, have been shown to physiologically restore normal cardiac function and reflex homeostatic cardiovascular control.

Radial artery compliance in essential hypertension: effects of antihypertensive therapy with lacidipine.

Abstract: OBJECTIVE To evaluate the effects of antihypertensive therapy with lacidipine on the increase in radial artery compliance observed in mild essential hypertensive patients. METHODS The study was performed in eight mild to moderate essential hypertensive patients in whom clinic blood pressure, radial artery diameter and radial artery compliance were evaluated before and after 3 months' administration of lacidipine, at a single daily dose of 4 mg. Radial artery diameter and compliance were evaluated by means of a high precision echo-tracking device able to assess arterial compliance over the blood pressure oscillations that characterize the cardiac cycle. RESULTS Lacidipine treatment caused a significant reduction in clinic systolic and diastolic blood pressure, while the heart rate was not modified by the drug. Radial artery diameter and compliance were both reduced by lacidipine over the entire systolodiastolic blood pressure range. CONCLUSIONS Chronic administration of lacidipine seems to reverse the increase in compliance observed in essential hypertension at the radial artery level. We suggest that lacidipine treatment can reverse an increase in the smooth muscle component in the arterial wall induced by hypertension.

Emerging Clinical Applications of Ambulatory Blood Pressure Recording

Abstract: Introduction: Pilot Ambulatory Care and Education Program (PACE) ....................................... Alan S. Robbins Preamble: Ambulatory Blood Pressure Monitoring ........................................................... Mohinder P. Sambhi I. Early Patient Compliance and Blood Pressure Control Using Home Readings ................ H. Mitchell Perry, Jr. II. Comparison of Hemodynamic Testing and 24-Hour Blood Pressure Monitoring and their Combined Use to Evaluate Antihypertensive Agents ...................................Per Lund-Johansen, Per Omvik and William White III. Ambulatory Blood Pressure Monitoring: Clinical Use and Technical Problems...................... Giuseppe Mancia IV. Ambulatory Blood Pressure Recording in Clinical Trials......................................................... Peter Sleight V. Ambulatory Blood Pressure Monitoring in Drug Evaluation ...................... AD. Bainbridge and John L. Reid