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D Rizzoni

Publications and source records attributed to D Rizzoni.

79 records · Page 5Linked to original sources
PubMed1990

[Clinical usefulness of non-invasive automatic monitoring of arterial blood pressure].

Recently, new devices for ambulatory blood pressure monitoring have been developed, which have become widely used as highly reliable diagnostic tools. It is now necessary to establish the rationale for their use, and to fully elucidate the diagnostic, prognostic and therapeutic advantages for their use in hypertensive patients. Average 24-hour blood pressure is more closely correlated with the degree of structural cardiovascular alterations than casual blood pressure measurements. Non-invasive blood pressure monitoring therefore seems to be more useful, from a prognostic point of view, than traditional, sphygmomanometric measurement. There is some evidence that ambulatory blood pressure monitoring is more reliable than casual measurements in assessing the efficacy of antihypertensive therapy. From a diagnostic point of view, the significance of blood pressure values obtained with these devices, and the most appropriate index to evaluate the 24-hour blood pressure load remain to be clarified. It is necessary to identify new normal limits for monitored blood pressure values i.e. to establish the baseline level for the start of treatment. At present, due to the lack of widely accepted upper limits of monitored blood pressure, the therapeutic decision should be based on casual blood pressure values, obtained with traditional mercury sphygmomanometer.

Blood Pressure↗
PubMed1987

Effects of infusing alpha-atrial natriuretic peptide in primary hypertension during converting enzyme inhibition.

The effect of atrial natriuretic peptide (ANP), before and after converting enzyme (CE) inhibition, was investigated in six primary hypertensive patients taking a constant diet. In this placebo-controlled, single-blind, randomized study, the patients received, on three different days, i.v. infusions of (a) placebo, or (b) alpha-human ANP, 150 micrograms over 30 min, or (c) alpha-human ANP after acute CE inhibition by enalapril (EN) 20 mg P.O., 4 h before ANP infusion. ANP infusion increased urinary sodium (p less than 0.001) and volume excretion. Blood pressure (BP), heart rate, stroke volume and shortening fraction (echocardiography), plasma renin activity (PRA), and plasma aldosterone did not change significantly. Urinary norepinephrine and dopamine were significantly increased (p less than 0.05) after ANP infusion. BP was significantly reduced after EN in every patient (p less than 0.05). ANP infusion during CE inhibition induced a more sustained increase of sodium excretion and diuresis with respect to ANP infusion alone (p less than 0.05). PRA was significantly reduced while no further reduction of BP was observed. These data suggest that CE inhibition may increase the natriuretic and diuretic effect of ANP in hypertensive patients.

Adolescent↗
PubMedDate not supplied

High-dose, not low-dose insulin increases the vasoconstrictor effect of norepinephrine in spontaneously hypertensive rats: effects of antihypertensive treatment.

The effect of insulin on the vasoconstriction induced by norepinephrine is presently controversial. Therefore, the aims of our study were: (1) to evaluate the effect of low- and high-dose insulin on the concentration-response curve to norepinephrine in small resistance arteries of spontaneously hypertensive rats (SHR) and Wistar Kyoto rats (WKY) before and after the development of hypertension, and (2) to evaluate the effects of antihypertensive treatment on vascular response to insulin and norepinephrine. Fifty-six rats were included in the study. Six SHR were treated with enalapril and 6 with candesartan cilexetil from the 4th to the 12th week of age, while 10 WKY and 14 SHR were kept untreated. Two additional groups of 10 untreated SHR and 10 WKY were killed at 4 weeks of age, in a prehypertensive phase. Mesenteric small arteries were dissected and mounted on a micromyograph. A dose-response curve to norepinephrine was performed at cumulative concentrations in the presence or absence of low- and high-dose insulin. We found that only high-dose insulin increased the vascular response to norepinephrine in 12-week-old SHR, but not in 4-week-old SHR or in age-matched WKY. The increased responsiveness to norepinephrine disappeared after preincubation of the vessels with a selective inhibitor of endothelin-1 type A receptors. After antihypertensive treatment with enalapril or candesartan cilexetil, the potentiation of the vasoconstrictor response to norepinephrine was abolished. In conclusion, insulin at high, nonphysiological doses seems to induce an increase in the reactivity to norepinephrine in mesenteric small arteries of SHR, possibly mediated by a local production of endothelin-1. Antihypertensive treatment with an ACE inhibitor or an angiotensin II receptor blocker may normalize this altered response. This mechanism may be relevant in the development of hypertension in SHR.

Angiotensin Receptor Antagonists↗
PubMedDate not supplied

Cardiovascular structural alterations in hypertension: effect of treatment.

Available data support the hypothesis that antihypertensive drugs may determine a significant regression of cardiac and vascular structural changes. Antihypertensive drugs that inhibit the renin-angiotensin or, to a lesser extent, the adrenergic system may more consistently and promptly reduce left ventricular hypertrophy (LVH) and vascular structural changes. It is possible that all antihypertensive agents, when used for long enough periods, will reduce LV mass, whereas only certain drugs will reduce mass within a period of few months, so that any difference among classes of antihypertensive drugs is more quantitative than absolute. However, a rapid reversal of LVH may be particularly important because reducing blood pressure in the presence of an elevated LV mass may be associated with impairment of coronary perfusion. Structural changes of small resistance arteries play a significant role in the genesis of increased vascular resistance in hypertension and in the maintainance of high blood pressure values. Studies in humans have demonstrated that minimal vascular resistance can be reduced with the use of different antihypertensive drugs, while a complete normalization of the media: lumen ratio was observed only with ACE inhibitors. Further studies are needed to assess the true clinical impact, in terms of reduced morbidity and mortality of reversal of cardiovascular structural changes in hypertensive patients. However, available studies indicate that reversal of LVH reduces the pathological consequences of increased left ventricular mass, and preliminary data suggest that complete regression of LVH may be associated to a decreased risk for cardiovascular events.

Antihypertensive Agents↗
PubMedDate not supplied

Late taste disorders in bone marrow transplantation: clinical evaluation with taste solutions in autologous and allogeneic bone marrow recipients.

The aim of this work was to determine the type and the significance of taste disorders in allogeneic bone marrow transplanted patients. In a retrospective study the taste threshold of a cohort of 15 allogeneic bone marrow transplanted patients, 4-51 months after transplantation (mean: 30.6 +/- 15.8), was compared to the taste threshold of 8 autologous bone marrow recipients, 4-48 months after transplantation (mean: 24.12 +/- 12.18), and to the taste threshold of a group of 20 consecutive normal subjects. Allogeneic bone marrow transplanted patients showed a significant hypogeusia for salt (Pearson's chi square p = 0.0002; Yates' correction p = 0.0007) and sour (Pearson's chi square p = 0.001; Yates' correction p = 0.008). No significant variations were observed for sweet and bitter. Autologous bone marrow recipients did not show any significant variation of taste acuity for sweet, salt or sour; a constant reduction of the taste threshold for bitter was observed, but the values were not significantly different from normal (Pearson's chi square p = 0.47; Yates' correction p = 0.83). So, late and selective taste disorders are observed in allogeneic bone marrow transplanted patients. Since the severity of the disorders is not strictly related to the severity of chronic oral G.V.H.D., taste analysis could discover the slightest, clinically undetectable cases of chronic oral G.V.H.D. The mechanism of immune aggression on the sensorial taste cells is poorly understood. Further trials are needed to define variations of taste acuity not only after allogeneic bone marrow transplantation, but also in systemic immune diseases.

Adolescent↗
PubMedDate not supplied

[Hemodynamic and humoral effects of 2 different doses of ketanserin in aged patients with hypertension].

The purpose of this double blind, cross-over, randomized study was to assess the antihypertensive efficacy and tolerability of ketanserin given at two different doses (i.e. 20 or 40 mg b.i.d.) in a group of patients with essential hypertension aged over 60 years. In addition, we evaluated the effect of ketanserin on some indexes of the sympathetic nervous system activity and the renin-angiotensin-aldosterone system, as well as the pharmacokinetic characteristics of the drug after acute administration per os and during chronic treatment. Twelve hypertensive patients, 6 males and 6 females gave their informed consent to the study. Each patient underwent a non invasive blood pressure monitoring after a wash out period with placebo, after 5 weeks of treatment with ketanserin (20 or 40 mg b.i.d.), after a second wash out period with placebo, and after a second period of treatment (5 weeks) with ketanserin (40 or 20 mg b.i.d.). In addition, we evaluated ketanserin plasma levels during acute and chronic administration. During treatment with ketanserin 20 mg b.i.d. systolic and diastolic blood pressure showed a small, statistically not significant reduction. The higher dose (40 mg b.i.d.) reduced systolic and diastolic blood pressure. Three hours after administration of 40 mg of the drug, ketanserin plasma levels were higher than after administration of 20 mg; this difference disappeared after 24 hours. A statistically significant relationship between mean blood pressure reduction during chronic treatment and ketanserin plasma levels was detected. No adverse effects were detected. In conclusion, ketanserin seems to be well tolerated and useful in antihypertensive therapy in elderly patients, particularly at the dose of 40 mg b.i.d.

Age Factors↗