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Showing papers by "Giuseppe Mancia published in 1996"


Journal ArticleDOI
TL;DR: In the anaesthetized rat acute increases in heart rate are accompanied by reductions in arterial compliance and distensibility, and the effect is greater in elastic than in muscle arteries.
Abstract: ObjectivesViscous and inertial components contribute to arterial distensibility and compliance in vitro. The purpose of our study was to determine whether this phenomenon is of relevance in vivo, namely, whether arterial compliance is altered by an increase in heart rateDesignArterial diameter was a

182 citations



Journal ArticleDOI
TL;DR: In subjects with a marked increase in serum cholesterol due to FHC, not only arteriolar dilatation, but also RAC and distensibility are markedly impaired, and this impairment can be favourably affected by an effective lipid lowering treatment of long duration.

96 citations


Journal ArticleDOI
TL;DR: Although in some instances SA of cardiovascular signals may fail to fully reflect the features of autonomic cardiovascular control, the evidence discussed clearly demonstrates that this approach represents a promising tool for a dynamic assessment of the early impairment of neural circulatory control in autonomic failure.
Abstract: Spectral analysis (SA) of blood pressure (BP) and heart rate (HR) fluctuations has been proposed as a unique approach to obtain a deeper insight into cardiovascular regulatory mechanisms in health and disease. A number of studies performed over the last 15 years have shown that autonomic influences are involved in the modulation of fast BP and HR fluctuations (with a period <1 min), particularly at frequencies between 0.2 and 0.4 Hz [high frequency (HF) region or respiratory frequency] and around 0.1 Hz [mid frequency (MF) region]. In patients with secondary or primary autonomic dysfunction, SA of BP and HR signals recorded at rest or during orthostatic challenge in a laboratory environment have shown the occurrence of a reduction in the power of MF and/or HF, BP and HR components. Such a reduction is associated or may even precede the clinical manifestation of autonomic neuropathy. However, the above results collected in standardized laboratory conditions cannot reflect the features of neural cardiovascular control during daily life in ambulant individuals with autonomic failure. To investigate this issue, SA techniques have been applied to 24 h beat-to-beat intra-arterial and non-invasive finger BP recordings obtained in elderly subjects and in pure autonomic failure patients, respectively. In these conditions, HR powers displayed a reduction over a wide range of frequencies (from 0.5 to below 0.01 Hz). Conversely, BP powers underwent a complex rearrangement characterized by a reduction in the power around 0.1 Hz and by an increase in the powers at the respiratory frequency and at frequencies below 0.01 Hz. Dynamic quantification of the sensitivity of the baroreceptor-heart rate reflex by combined analysis of systolic BP and pulse interval (i.e. the interval between consecutive systolic peaks) powers around 0.1 Hz (alpha technique) has shown that in elderly subjects, and even more so in pure autonomic failure patients, baroreflex sensitivity is markedly reduced over the 24 h, and is no longer characterized by its physiological day-night modulation. In conclusion, although in some instances SA of cardiovascular signals may fail to fully reflect the features of autonomic cardiovascular control, the evidence discussed clearly demonstrates that this approach represents a promising tool for a dynamic assessment of the early impairment of neural circulatory control in autonomic failure. This is particularly the case when these analyses are performed on 24 h continuous BP and HR recordings in ambulant subjects.

70 citations


Journal ArticleDOI
TL;DR: The centenary of blood pressure measurement:a tribute to Scipione Riva-Rocci Alberto Zanchetti;Giuseppe Mancia; Journal of Hypertension
Abstract: The centenary of blood pressure measurement:a tribute to Scipione Riva-Rocci Alberto Zanchetti;Giuseppe Mancia; Journal of Hypertension

48 citations


Journal ArticleDOI
TL;DR: A considerable clinic-ambulatory blood pressure difference persists during several weeks of antihypertensive treatment, but its magnitude is significantly attenuated, which leads to an overestimation of the effectiveness of anti Hypertensive Treatment when this is assessed by clinic blood pressure measurements only.
Abstract: Objective To investigate whether a clinic-ambulatory blood pressure difference persists with time under active drug treatment or placebo and to determine whether and how it interferes with the evaluation of the efficacy of antihypertensive treatment. Design and methods In 382 mild or moderate essential hypertensive patients (mean age +/- SD 51.5 +/- 9.2 years) clinic and ambulatory (SpaceLabs 90207 device) blood pressures were measured twice, under baseline conditions and after 4-8 weeks of antihypertensive treatment by calcium antagonists or angiotensin converting enzyme inhibitors (n = 266) or of placebo administration (n = 116). In each patient the difference between clinic and daytime average blood pressure was taken as a surrogate measure of the magnitude of the 'white-coat effect', separately for systolic and diastolic blood pressures. The changes in this difference induced by treatment and by placebo and the relationship between the blood pressure changes induced by drug treatment and by placebo and the magnitude of the difference before and during treatment or placebo, respectively, were computed. Results Before drug treatment, the difference was 16.6 +/- 13.6 and 10.1 +/- 7.9 mmHg for systolic and diastolic blood pressures, respectively. During treatment the corresponding values were 11.9 +/- 14.2 and 6.8 +/- 9.2 mmHg; both of the reductions were statistically significant. Both for systolic and for diastolic blood pressure, the reduction in clinic blood pressure caused by treatment was directly related to the clinic-ambulatory difference before treatment, but inversely related to the magnitude of that difference persisting during treatment. The clinic-ambulatory blood pressure difference observed before placebo was attenuated during placebo, the magnitude of the attenuation being similar to that found under drug treatment. No significant difference between clinic and daytime average heart rate was ever observed before and during active treatment or placebo. Conclusions A considerable clinic-ambulatory blood pressure difference persists during several weeks of antihypertensive treatment, but its magnitude is significantly attenuated. This leads to an overestimation of the effectiveness of antihypertensive treatment when this is assessed by clinic blood pressure measurements only. This overestimation is greater in subjects with an initially greater difference because in these subjects the subsequent attenuation is greater. Because similar phenomena are observed with placebo, the attenuation in the difference during drug treatment is likely to reflect merely habituation to clinic blood pressure measurements with time.

41 citations


Journal ArticleDOI
TL;DR: The recent introduction of continuous noninvasive ambulatory blood pressure monitors offers the unique possibility of obtaining dynamic information on neural cardiovascular control in clinical conditions in which the assessment of autonomic cardiovascular regulation may have diagnostic and prognostic implications.
Abstract: The availability of ambulatory intraarterial blood pressure monitoring techniques offers a deeper insight into the features of blood pressure variability over 24 hours and allows better understanding of the mechanisms responsible for the continuous and marked blood pressure changes that occur throughout the day and at night. Among these mechanisms, central and reflex neural influences play a major role. This has led to the development of techniques for the assessment of 24-hour "spontaneous" baroreflex sensitivity through combined computer analysis of blood pressure and heart rate variations in the time or frequency domain. The recent introduction of continuous noninvasive ambulatory blood pressure monitors offers the unique possibility of obtaining dynamic information on neural cardiovascular control in clinical conditions in which the assessment of autonomic cardiovascular regulation may have diagnostic and prognostic implications.

39 citations



Journal ArticleDOI
TL;DR: New techniques have been developed which allow to measure arterial compliance non invasively and continuously over the range of existing blood pressure values, and the new data available on these issues will be focused on.
Abstract: Compliance is a measure of the elastic properties of arterial vessels and is a function of blood pressure. In recent years new techniques have been developed which allow to measure arterial compliance non invasively and continuously over the range of existing blood pressure values. It has been thus possible to investigate the alterations of arterial compliance in a variety of diseases and to address the physiological factors involved in arterial compliance modulation. This article will focus on the new data available on these issues.

26 citations


Journal ArticleDOI
TL;DR: This paper briefly reviews the information provided by clinical trials on antihypertensive treatment and critically examines the questions that have remained partially or totally unanswered and the trials that are currently addressing them.
Abstract: Conclusive evidence from large-scale epidemiological studies has shown that hypertension is a major risk factor for cardiovascular disease. Large-scale intervention trials have indicated that, by reducing elevated blood pressure values with antihypertensive treatment, the risk can be decreased. Despite the large body of evidence on the protective effects of the blood pressure reduction, several questions concerning the benefit of antihypertensive treatment remain unanswered. This paper briefly reviews the information provided by clinical trials on antihypertensive treatment. It also critically examines the questions that have remained partially or totally unanswered and the trials that are currently addressing them. Focus is directed on the Insight Study which addresses the benefit of antihypertensive treatment in hypertensive subjects with additional cardiovascular risk factors.

23 citations


Journal ArticleDOI
TL;DR: This review focuses on guideline modifications of the past 20 years and describes the main similarities and differences between the guidelines recently published by the World Health Organization/International Society of Hypertension committees and the US Joint National Committee.
Abstract: Guidelines for the pharmacologic and nonpharmacologic management of hypertension were first published in the 1970s and subsequently revised in the 1980s and 1990s. In this review, we focus on guideline modifications of the past 20 years and describe the main similarities and differences between the guidelines recently published by the World Health Organization/International Society of Hypertension committees and the US Joint National Committee. These guidelines agree on fundamental issues such as the careful assessment of patients' overall risk and target-organ damage, the treatment of elderly hypertensive individuals and isolated systolic hypertension, and the importance of persistent blood pressure reduction below 140 90 mm Hg. The committees also disagree in a few areas, such as the class of drugs to be used as first-line treatment and the use of ambulatory blood pressure monitoring. These disagreements reflect the limited scientific evidence on these specific topics.

Journal ArticleDOI
TL;DR: It is hoped that new anti-hypertensive agents, which smoothly reduce 24-h blood pressure profile, will further reduce the incidence of hypertension-related end-organ damage.
Abstract: Hypertension is common throughout the world and represents the single greatest risk factor for increasing cardiovascular mortality, cardiovascular morbidity and overall mortality. Diseases associated with hypertension are not only, in general, of a chronic disabling nature, but, in most instances, require frequent hospitalization, with expensive drug treatment and management. Stroke, coronary heart disease, congestive heart failure and chronic renal insufficiency represent the most commonly encountered corollaries of inadequately treated hypertension. Anti-hypertensive treatment is accompanied by a reduction of hypertension-related cardiovascular risk and a clearcut benefit in terms of reduced incidence of major cardiovascular complications of hypertension and overall mortality. This benefit has frequently been underestimated in many clinical trials. Attempts to improve the cost benefit ratio have included the use of treatment strategies based upon 24-h control of blood pressure, since it has been demonstrated that hypertension-related end-organ damage correlates more closely with 24-h average blood pressure and with 24-h blood pressure variability than with blood pressure measured in the clinic. It is hoped that new anti-hypertensive agents, which smoothly reduce 24-h blood pressure profile, will further reduce the incidence of hypertension-related end-organ damage.

Journal ArticleDOI
TL;DR: Broad-band spectral analysis techniques have allowed us to obtain experimental evidence that the arterial baroreflex exerts its influence not only on fast but also on slow components of blood pressure and heart rate, i.e., on components with periods longer than 60 sec.
Abstract: This paper focuses on a number of methods for the analysis of the relationship between the arterial baroreflex and different components of blood pressure and heart rate variability. Broad-band spectral analysis techniques have allowed us to obtain experimental evidence that the arterial baroreflex exerts its influence not only on fast but also on slow components of blood pressure and heart rate, i.e., on components with periods longer than 60 sec. Focusing on faster changes in blood pressure and heart rate, both time domain and frequency domain techniques have been developed to track the sensitivity of baroreflex heart rate modulation over time, either in laboratory or in daily life conditions. These approaches have considerably broadened our understanding of the role of baroreflex modulation of the heart and peripheral circulation in a number of pathological and physiological conditions.

Journal ArticleDOI
TL;DR: Nocturnal hypotension seems to be unaffected by renovascular hypertension and can therefore be used as a diagnostic criterion for this condition.
Abstract: OBJECTIVE To investigate whether nocturnal blood pressure fall is blunted in renovascular hypertension and can therefore be used as a diagnostic criterion for this condition. METHODS In 14 renovascular hypertensive patients (age 43.8+/-2.1 years, mean+/-SEM, clinic blood pressure 173.6+/-3.7 mmHg systolic and 109.0+/-2.0 mmHg diastolic) and in 14 age- and blood pressure-matched essential hypertensive controls 24 h ambulatory blood pressure was measured after washout from drug treatment, during angiotensin converting enzyme inhibitor treatment and, in renovascular hypertension, also after percutaneous transluminal renal angioplasty. RESULTS The 24 h average systolic and diastolic blood pressures were 146.4+/-5.7 and 97.5+/-3.6 mmHg in renovascular and 144.3+/-1.2 and 98.0+/-2.2 mmHg in essential hypertensive patients. The angiotensin converting enzyme inhibitor treatment reduced 24 h average systolic and diastolic blood pressures by 8.5% and 9.7% in the renovascular and by 8.3% and 10.8% in the essential hypertensive group. Greater systolic and diastolic blood pressure reductions (-18.2% and -18.1%) were observed in renovascular hypertensive patients after percutaneous transluminal renal angioplasty. Blood pressure fell by about 10% during the night and the fall was similar in renovascular and in essential hypertensive patients. In the former group, nocturnal hypotension was similar after washout, during angiotensin converting enzyme inhibitor treatment and after percutaneous transluminal renal angioplasty. Similar results were obtained for nocturnal bradycardia. CONCLUSIONS Nocturnal blood pressure fall is equally manifest in renovascular and essential hypertension. The removal of the renal artery stenosis and blood pressure normalization do not enhance this phenomenon. Nocturnal hypotension seems therefore to be unaffected by renovascular hypertension.



Journal Article
TL;DR: An alternative and simple way to obtain reproducible blood pressure values, without making use of ambulatory blood pressure monitoring techniques, may be offered by the average of 20-25 blood pressure readings obtained automatically or semi-automatically under standardized conditions in outpatient clinics.
Abstract: Clinic blood pressure readings are less reproducible than 24 h and daytime average ambulatory blood pressures. This may depend on (1) the continuous and spontaneous variability which characterizes daily life blood pressure, (2) the well-known 'white-coat' effect and (3) other methodological problems affecting traditional sphygmomanometric readings, such as the observer's bias and digit preference. The higher reproducibility of average 24 h and daytime blood pressures is also, at least in part, a function of the greater number of blood pressure readings available. On the other hand, the various components of the 24 h blood pressure profile appear, in general, to be less reproducible than the 24 h average value. This is the case for hourly values, for the day-night blood pressure difference and for a number of statistical parameters employed for modelling the 24 h blood pressure curve. An alternative and simple way to obtain reproducible blood pressure values, without making use of ambulatory blood pressure monitoring techniques, may be offered by the average of 20-25 blood pressure readings obtained automatically or semi-automatically under standardized conditions in outpatient clinics. The implications of these findings for clinical trials aimed at evaluating the features of the effects of antihypertensive drugs on 24 h blood pressure are discussed.


Journal ArticleDOI
TL;DR: INSIGHT is the first trial to address, in a prospective fashion, the prognostic influence of antihypertensive treatment in hypertensives with concomitant risk factors.
Abstract: BLOOD PRESSURE REDUCTION AND CARDIOVASCULAR MORBIDITY AND MORTALITY: Several hypertension trials have shown that antihypertensive treatment can reduce the cardiovascular morbidity and mortality accompanying this condition. They have also shown, however, that the reduction does not entirely normalize the risk of hypertensive patients. STRATEGIES TO IMPROVE THE BENEFIT OF ANTIHYPERTENSIVE TREATMENT: Although some of the risk of the hypertensive patient may prove to be irreversible, pathophysiological and clinical evidence obtained in recent years suggests that some modifications to antihypertensive treatment strategies might increase the benefit. For example, greater use of drugs such as calcium antagonists and angiotensin converting enzyme (ACE) inhibitors as first-line agents might bring greater benefits, because some properties of these drugs which are additive to their blood pressure lowering effects, such as regression of cardiovascular structural changes, nephroprotection and delay of atherogenesis, may provide a degree of protection against target-organ damage. ONGOING CLINICAL TRIALS AND THE INTERNATIONAL NIFEDIPINE (GITS) GASTROINTESTINAL SYSTEM STUDY OF INTERVENTION AS A GOAL IN HYPERTENSIVE TREATMENT (INSIGHT): Several ongoing clinical trials are aimed at comparing the effects of calcium antagonists and ACE inhibitors versus beta-blockers and diuretics on cardiovascular morbidity and mortality. INSIGHT is particularly interesting because the effects of nifedipine GITS and a combined thiazide and potassium-sparing diuretic on cardiovascular morbidity and fatal events are being compared in patients with hypertension plus one or more additional risk factors, such as hypercholesterolemia, smoking, diabetes, left ventricular hypertrophy, etc. INSIGHT is therefore the first trial to address, in a prospective fashion, the prognostic influence of antihypertensive treatment in hypertensives with concomitant risk factors.