Search PubMed⌕ Search

Biomedical subjects

M Castellano

Publications and source records attributed to M Castellano.

At least 127 records · Page 7Linked to original sources
PubMed1988

Beneficial effects of one year's treatment with captopril on left ventricular anatomy and function in hypertensive patients with left ventricular hypertrophy.

This study evaluated by echocardiography (M-mode tracings, two-dimensional-guided) the effects of captopril administration for one year (25 to 50 mg twice a day, alone or in combination with hydrochlorothiazide when necessary) on left ventricular mass index, on systolic function at rest and during stress (hand grip for three minutes and cold pressor test for three minutes), and on diastolic function in 15 patients with essential hypertension (13 men and two women, aged 30 to 67 years) with left ventricular hypertrophy. In addition, supine and standing plasma catecholamine concentrations, plasma renin activity, and plasma aldosterone levels were measured. Examinations were performed during a placebo period and after three, six, and 12 months of captopril treatment. Blood pressure was significantly reduced (p less than 0.001), but heart rate did not change. Left ventricular hypertrophy was progressively reduced during treatment, mainly through reduction of left ventricular wall thickness. After one year, all patients had a normal left ventricular mass index (less than 120 g/m2). Before and during treatment, left ventricular systolic function, at rest and on maximal hand grip and cold pressor testing, evaluated on the basis of fractional shortening as related to end-systolic stress, was within the 95 percent confidence limits (calculated in a group of 25 normal subjects) in all 15 patients with essential hypertension. The percent increase in left ventricular dimensions during the diastolic rapid filling phase was significantly increased by treatment (p less than 0.05), indicating improvement of left ventricular relaxation. As expected, plasma renin activity was increased, plasma aldosterone levels were decreased, and plasma catecholamine concentrations did not change. These results indicate that long-term treatment with captopril has beneficial effects on left ventricular anatomy and function in patients with essential hypertension.

Adult↗
PubMed1988

Plasma catecholamines and heart rate at the beginning of muscular exercise in man.

The relationship between the time course of heart rate and venous blood norepinephrine (NE) and epinephrine (E) concentrations was studied in 7 sedentary young men before and during 3 bicycle exercises of 5 min each (respectively 23 +/- 2.8%, 45 +/- 2.6% and 65 +/- 2.4% VO2max, mean +/- SE). During the low level exercise the change in heart rate is monoexponential (tau = 5.7 +/- 1.2 s) and no increment above the resting level of NE (delta NE) or of E (delta E) occurs. At the medium and highest intensity of exercise: a) the change in heart rate is biexponential, tau for the fast and the slow component averaging about 3 and 80 s respectively; b) delta NE (but not delta E) increases continuously with time of exercise; c) at the 5th min of exercise heart rate increments are related to delta NE; d) between 20 s and 5 min, at corresponding sampling times, the heart rate of the slow component is linearly related to delta NE. At exercise levels higher than 33% VO2max the increase in heart rate described by the slow component of the biexponential kinetic could be due to an augmented sympathetic activity revealed by increased NE blood levels.

Adult↗
PubMed1988

Metabolic and hormonal effects of preferential beta 1 and beta 2-adrenoceptor stimulation in man.

The changes of blood glucose, serum potassium (K+), plasma non-esterified fatty acids (NEFA), plasma insulin and plasma renin activity (PRA) following the preferential stimulation of beta-1 and beta-2 adrenoceptors were studied in 7 healthy subjects during a 60-min infusion of prenalterol, a new, relatively beta-1 selective agonist and salbutamol, a well known, relatively beta-2 selective agonist. Two different high and low doses were used for both agents: 300 micrograms and 600 micrograms and 1 mg and 2 mg for salbutamol and prenalterol, respectively. The levels of PRA seemed equally increased by the two agents in proportion to the dose infused, thus suggesting an equally important role for beta-1 and beta-2 adrenoceptors in renin release. Blood glucose did not change during prenalterol infusions, while increased by 12 +/- 2 mg/100 ml (mean +/- SE; p less than 0.01) and 25 +/- 3 mg/100 ml (p less than 0.01) on salbutamol, at low and high dose, respectively. Similarly the decrement of serum K+ was significantly more pronounced (p less than 0.01) after salbutamol infusion (0.6 +/- 0.07 mEq/L and 1.0 less than 0.09 mEq/L, at low and high dose, respectively) than after prenalterol (0.1 +/- 0.07 mEq/L and 0.3 +/- 0.05 mEq/L). These metabolic effects should suggest a main beta-2 adrenoceptor involvement.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1988

Long-term antihypertensive treatment may induce normalization of left ventricular mass before complete regression of vascular structural changes: consequences for cardiac function at rest and during stress.

In 14 essential hypertensive patients, aged 26-59 years, blood pressure, left ventricular mass index (LVMI), systolic function (M-mode echo, two-dimensionally guided), post-ischaemic 'maximal' forearm blood flow (strain gauge venous occlusion plethysmography), plasma renin activity, plasma catecholamines and aldosterone were measured before and after 6 and 12 months of treatment (eight patients were given captopril, 100 mg/day, + hydrochlorothiazide 25 mg/day in five patients, and six patients were given nitrendipine, 20 mg/day, + atenolol 50 mg/day in four patients). Minimal vascular resistance (mean blood pressure/peak forearm blood flow) was taken as an index of arterial structural changes. After 6 months of treatment significant reductions in blood pressure (P less than 0.001), LVMI (P less than 0.001) and minimal vascular resistance were observed. After 12 months of treatment blood pressure, LVMI and minimal vascular resistance were further reduced. The LVMI was normalized in nine cases and the minimal vascular resistance in two cases only. Aldosterone and plasma catecholamines did not change, whereas plasma renin activity was increased during captopril only. Before and during treatment the left-ventricular shortening fraction in relation to end-systolic stress in each patient at rest, and at peak of handgrip and cold pressor tests, fell within the 95% confidence limits of correlation obtained in normals. Thus, in essential hypertensives long-term treatment can induce normalization of LVMI before complete regression of arterial structural changes in the forearm. Left ventricular systolic function is preserved after normalization of LVMI, both at rest and during stress.

Adult↗
PubMed1988

Cardiovascular and hormonal responses to DDAVP before and after beta-blockade in patients with mild essential hypertension.

The aim of this study was to assess the cardiovascular and hormonal responses to 1-desamino-8,D-arginine vasopressin (DDAVP) in hypertensive patients before and after non-selective beta-blockade. We infused DDAVP at 400 ng/kg body weight for 10 min in nine subjects with mild essential hypertension before and 14 days after administration of nadolol at 80 mg/day. Blood pressure and heart rate were recorded, and blood was drawn at 0, 30 and 60 min for measurement of plasma renin activity, aldosterone, cortisol, noradrenaline, adrenaline and dopamine. Before the administration of nadolol, DDAVP induced a significant decrease in blood pressure, and significant increases in the heart rate, plasma renin activity, cortisol and noradrenaline; there were no changes in adrenaline or dopamine. After the administration of nadolol, baseline noradrenaline was significantly increased, while cortisol, adrenaline and dopamine remained unchanged. A second infusion of DDAVP did not significantly alter blood pressure, [corrected] heart rate, noradrenaline, adrenaline or dopamine, but plasma renin activity, aldosterone and cortisol still showed a significant increase. The blunted hypotensive effect of DDAVP after the administration of nadolol may be aspecific, due to lower basal blood pressure levels, or may indicate a mechanism of action common to both drugs. A similar post-DDAVP increase before and after beta-blockade suggests that the drug has a direct effect on the renin-secretory apparatus. An indirect effect, mediated by changes in intrarenal haemodynamics or by other factors with renin-stimulating activity, e.g. tissue plasminogen activator, can also be hypothesized.

Adult↗
PubMed1988

Reversal of cardiac hypertrophy by long-term treatment with calcium antagonists in hypertensive patients.

The aim of this study was to assess the effects of chronic antihypertensive treatment with verapamil and nifendipine on left ventricular (LV) anatomy and function, also in relation to adrenergic activity and beta-adrenergic sensitivity. In fact, it is known that, during antihypertensive treatment, changes of LV mass and function may be affected also by the level of adrenosympathetic tone. Blood pressure (BP), heart rate (HR), plasma catecholamines (pCA), beta-adrenergic responsiveness to isoproterenol (dose that increased HR by 25 beats/min = CD25), LV mass as well as systolic function (2D-guided M-mode echo), at rest and during stress (handgrip test [HG], 30% max, for 3 min), were measured on placebo, after 1 and 6 months of monotherapy with verapamil (VER, 240 mg/day, 9 patients) or nifedipine (NIF, 40 mg/day, 10 patients). Both treatments significantly reduced BP (p less than 0.05 at least). HR, pCA, and cardiac output did not change during treatment with VER, whereas they were slightly but significantly increased during treatment with NIF (p less than 0.05 at least). CD25 was significantly increased during treatment with VER (p less than 0.05) but not during treatment with NIF. Both treatments induced a significant reduction of LV mass after 6 months (p less than 0.01 with VER and p less than 0.05 with NIF).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1988

Sympathetic activation on effort in patients with chronic heart failure. Long term effects of captopril.

Ten patients with congestive heart failure (CHF) (NYHA II-IV) on adjusted doses of digitalis and diuretics underwent a careful clinical assessment including an evaluation of exertion dyspnoea and the usual echocardiographic indices of cardiac performance. A cardiopulmonary exercise test with an increment of 20W every 3 minutes was prolonged until exhaustion. Systemic arterial pressure, ECG, VO2, VCO2 and VE were monitored throughout. Gas tensions, plasma catecholamines and lactate were measured in blood samples taken at the first and third minute of each exercise stage. The above measurements were carried out before and after 3 months of treatment with Captopril, 50 mg b.i.d. or t.i.d. A highly significant correlation between arterial lactate and plasma norepinephrine (NE) was observed in each patient during both exercise tests (r = 0.77 to 0.99; p less than 0.05 at least). Left ventricular end-diastolic dimensions were reduced by Captopril (from 69.9 +/- 1.7 to 65.2 +/- 1.4 mm, p less than 0.01) along with a concomitant increase in percent fractional shortening. Most of the patients were reclassified at a lower NYHA class and a significant decrease in dyspnoea score was observed. The exercise time was significantly increased (from 11.2 +/- 1.8 to 12.9 +/- 1.9 min; p less than 0.05), but the peak values of NE, arterial lactate and VO2 were not affected by the treatment. The predicted value of VE at a VCO2 of 1 L/min, regarded as an index of dyspnoea, was significantly decreased by Captopril (from 41.4 +/- 2.9 to 38.9 +/- 2.7 L/min; p less than 0.05). The positive effects of long-term treatment with Captopril on cardiac performance in CHF are confirmed. Sympathetic activity is linked to anaerobic muscular metabolism during exercise and seems to be independent of pharmacological ACE inhibition. The discrepancy between the exercise tolerance and the peak VO2 might be explained by a better utilization of the available energy.

Adult↗
PubMed1988

Pathological spectrum of the lung in cases of violent death: Part I. Lesion classification.

The results are presented of the pathological study of the lungs in 66 cases of violent death observing the more frequent types of lesions and establishing 4 different groups of postlesioned pulmonary condition. 1. Inflammatory alveolar lesions without a diffused interstitial involvement (IAL) including contusions or direct aggressions, lobular pneumonias, or bronchopneumonias with a predominance of intra-alveolar inflammatory exudation. 2. Inflammatory alveolar lesions with a diffuse interstitial involvement (IALW) including generalized affectation of the parenchyma with lesions in the capillary structure of the wall. 3. Edemohemorrhagic lesions (EHL) presenting phenomena of capillary congestion with hematic extravasation and interstitial and intra-alveolar edema, without inflammatory involvement. This is the most numerous group and it can constitute the preliminary stage of any other. 4. Unspecific chronic lesions (UCL) not related to the cause of death, being chronically inflammatory and fibrotic alterations of limited interest in our study. We emphasize the importance of the inflammatory involvement of the alveolar wall in the pathogenia of diffuse alveolar damage (DAD) and the aggravation of pulmonary lesions by capillary structure alteration, direct lesion of alveolar epithelium, presence of macrophages, and liberation of certain intracellular enzymes.

Asphyxia↗
PubMed1988

Pathological spectrum of the lung in cases of violent death: Part II. Clinicopathologic correlation.

The correlation between the type of pathological lesion of the lung and the circumstances which encompass their evolution in 66 cases of violent death have been examined. Pulmonary lesions have been classified into four groups. 1. Inflammatory alveolar lesions without a diffuse interstitial involvement (IAL) which result from direct aggressions in subjects of advanced age. 2. Inflammatory alveolar lesions with a diffuse interstitial affectation (IALW) which are more frequent in younger subjects having a higher defense capacity and with severe lesions requiring admission to an intensive care unit. 3. Edemohemorrhagic lesions (EHL) appearing as a precocious lesion at any age. 4. Unspecific chronic lesions (UCL) previous to the aggression and without any relationship to death. The most obvious feature noted was the frequent occurrence of certain types of acute pulmonary lesions indicative of the rapid and extensive capacity of the lung to react to a lesion agent even when death follows rapidly after the aggression. The scarcity of acute interstitial lesions among the older group can be related to a diminution of biological defense activity leading to a less vigorous response; on the contrary, diffuse lesions of the wall seem to be related to an excess of defense mechanisms, determined more by age, severity of lesion, and type of medical assistance received than by a specific type of aggression.

Adult↗
PubMed1987

Captopril versus digoxin in mild-moderate chronic heart failure: a crossover study.

The effects on cardiac function of captopril (CPT) and digoxin (D) were compared in a study of 16 patients with chronic heart failure due to ischemic heart disease (15) and to congestive cardiomyopathy (1) (New York Heart Association class II n.13 and class III n.3). All patients were normotensive and in sinus rhythm. CPT 25 mg every 8 hours (t.i.d.) or D 0.25 mg once daily was given in a single-blind crossover design: A placebo (PLC) t.i.d. was given for 5 to 10 days, then CPT or D, according to a random sequence, replaced three or one of the PLC tablets; after one month, CPT and D were switched to PLC for 5 to 10 days; subsequently, the PLC tablets were replaced by CPT in the patients who previously received D and vice versa, and both treatments were again continued for one month. PLC, CPT, and D tablets were all identical. Diuretics once daily were given throughout the study. Plasma renin activity (PRA), plasma aldosterone (ALDO), plasma noradrenaline (NA), and adrenaline (A) were determined at the end of the two PLC periods and the two active treatments. A hand grip and a bicycle exercise were performed at the end of the two PLC periods and the two active treatments. No difference was noted between the PLC periods. PRA increased with CPT and did not change with D. ALDO was decreased by both CPT and D. NA and A were similarly decreased by both drugs, both supine and standing.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
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↗
PubMed1987

Cardiac function as related to adrenergic activity in hypertensive left ventricular hypertrophy.

Studies in experimental animals and in hypertensive patients have shown that changes in cardiac anatomy and function are not just a simple consequence of the increased pressure load. The activity of the sympathetic nervous system is one of the factors that may influence cardiac performance and also, possibly, the cardiac anatomy of hypertensive patients. Animal studies have strongly suggested a possible role of adrenergic factors in the development of left ventricular hypertrophy. In man, plasma catecholamines are usually higher in hypertensive patients with left ventricular hypertrophy, and a correlation between left ventricular mass and plasma noradrenaline has also been observed. The decrease of cardiac performance after acute beta blockade has been found to be directly related to basal plasma noradrenaline concentration. An impaired response to beta-adrenergic stimulation has been reported in hypertensive animals and has been confirmed in hypertensive patients with left ventricular hypertrophy.

Adult↗