PubMed Health⌕ Search

Biomedical subjects

S Cuomo

Publications and source records attributed to S Cuomo.

At least 37 records · Page 2Linked to original sources
PubMed1985

[Effect of beta-receptor block on QT/QS2 behavior during isometric and dynamic exercise].

Our study is aimed to evaluate the change of QT/QS2 ratio in normal subjects during both isometric and dynamic exercise before and after propranolol administration. We studied 10 young volunteers healthy subjects who performed an isometric exercise by squeezing a grip dynamometer at 70% of their maximal voluntary contraction as long as possible. They also performed a dynamic exercise undergoing a submaximal bicycle stress test. Both tests were performed before and after administration of propranolol (0.15 mg/Kg e.v.) QT and QS2 intervals were measured at rest, during exercise and in the recovery period. Heart rate and blood pressure were also determined. Isometric exercise induces a significant shortening of both intervals although minor for QT so that the ratio significantly increases in comparison to baseline (p less than .001). At rest propranolol induces a significant decrease of heart rate and only a slight lengthening of QT and QS2 so that the ratio is unchanged. During exercise propranolol does not influence the increase of heart rate and blood pressure and the shortening of QT interval but prevent exercise-induced QS2 shortening so that the ratio after beta-blockade is significantly reduced at the peak of exercise (p less than .005). During dynamic exercise QT and QS2 behaviour is similar to that of isometric exercise; in fact both intervals are shortened and QS2 decrease is major than QT so that the ratio increases (p less than .001). These results confirm that QT/QS2 ratio can monitor the effects of adrenergic stimulation on the heart during physiological manoeuvres enhancing sympathetic discharge like occurs during both isometric and dynamic exercise.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1984

QT/QS2 ratio as an index of autonomic tone changes.

The effects of changes in sympathetic tone on QT/QS2 ratio were studied in 10 healthy subjects aged 21 to 24 years. The subjects underwent a bicycle ergometer exercise, a tilt test, a decrease in carotid transmural pressure induced by means of pneumatic neck chamber, an i.v. injection of phenylephrine. A phonocardiogram and ECG were simultaneously recorded at a paper speed of 100 mm/s to evaluate QT and QS2 intervals in each test. In basal conditions, the QT/QS2 ratio was less than 1, whereas it increased progressively during the physical exercise and became greater than 1 at peak exercise. Both the upright position and the increase in neck-tissue pressure induced a significant increase in the QT/QS2 ratio as compared with the basal values, whereas i.v. administration of phenylephrine reduced significantly the QT/QS2 ratio. These results demonstrate that those stimuli which induce a rise in adrenergic activity may increase the QT/QS2 ratio. In contrast, the reflex inhibition of the adrenergic activity induced by phenylephrine is accompanied by a reduction in QT/QS2 ratio. Therefore, the QT/QS2 ratio might represent a reliable index of sympathetic cardiac tone.

Adult↗
PubMed1984

Influence of heart rate on exercise-induced R-wave amplitude changes in coronary patients and normal subjects.

In order to study whether different heart rates achieved at peak exercise by normal subjects and patients with coronary artery disease (CAD) affect the results of analysis of R-wave amplitude changes (delta R), we evaluated delta R at progressively increasing heart rate (HR) steps in 60 normal subjects with negative exercise tests (ET), in 130 patients with CAD, in 88 patients with true positive and 42 with false negative ET, and in 43 patients with no CAD and false positive ET. We found that the sensitivity and specificity of delta R were HR dependent, the former decreasing and the latter increasing with progressively increasing HR steps. Mean values of delta R did not discriminate among the four groups for HRs up to 150 bpm; significant differences were found between normal subjects and CAD patients, both with true positive and false negative stress tests, at HR greater than 150 bpm. False positive patients had mean delta R similar to those found in normal subjects. We hypothesize that quantitative delta R analysis could be useful in ECG diagnosis of false negative and false positive patients at HR greater than 150 bpm.

Coronary Disease↗
PubMed1984

Effects of different dopaminergic antagonists on bromocriptine-induced inhibition of norepinephrine release.

In this study we evaluated the effects of placebo or acute bromocriptine (BC) administration (2.5 mg orally) on plasma catecholamines, systolic and diastolic blood pressure (BP), heart rate, and plasma PRL in six normal subjects [group I, mean age 33.2 +/- 5.4 (SD) yr] in the supine as well as upright position. BC induced a significant decrease in plasma norepinephrine in the supine [167.7 +/- 16.8 (SEM) vs. 101.9 +/- 33.7 pg/ml, P less than 0.005] and upright positions [397.3 +/- 27.7 vs. 211.3 +/- 26.7 pg/ml, P less than 0.005], a decrease in systolic and diastolic BP and a decrease in plasma PRL (P less than 0.01). After standing, epinephrine levels increased significantly (53.6 +/- 11.8 vs. 226.4 +/- 71.0 pg/ml, P less than 0.05). The study was repeated in a second group of seven normal subjects (mean age, 32.3 +/- 12.9 yr) after placebo or metoclopramide (20 mg orally) plus BC. In this group metoclopramide, a central and peripheral antidopaminergic agent, counteracted the BC-induced effects found in group I, both in the basal and stimulated conditions. Plasma PRL increased significantly (P less than 0.025). Finally, to assess the effect of peripheral dopaminergic blockade on BC-induced changes in sympathetic outflow, we repeated the study in seven normal subjects (group III, mean age, 30.1 +/- 5.0 yr) after placebo or domperidone (20 mg orally) plus BC. Domperidone blocked the effects of BC on norepinephrine and BP in the supine position. On standing there was a significant decrease in systolic (P less than 0.05) and diastolic (P less than 0.05) BP and an increase in epinephrine levels (58.9 +/- 12.2 vs. 109.8 +/- 24.6 pg/ml, P less than 0.05) was still observed. Plasma PRL increased significantly (P less than 0.025). The results of this study suggest that the inhibition of sympathetic outflow induced by BC is peripherally mediated. As peripheral dopamine receptor blockade did not counteract all the effects after BC during standing, dopaminergic modulation of central reflex sympathetic activation is suggested.

Adult↗
PubMed1984

Effects of naloxone on catecholamine plasma levels in adult men. A dose-response study.

To evaluate a possible role for endogenous opiates in modulating sympathetic-adrenal function in humans, we measured plasma epinephrine and norepinephrine (radioenzymatic method), blood pressure and heart rate in 8 normal men (aged 24-33 years) before and after placebo or different doses (0.4, 4.8, 10 mg) of naloxone. In 6 subjects plasma insulin and glucagon levels were also measured by radioimmunoassay after placebo and 10 mg naloxone. Naloxone had no significant effect upon blood pressure, heart rate, plasma insulin, glucagon or norepinephrine. Placebo, 0.4 and 4.8 mg naloxone caused no significant change in peripheral levels of epinephrine while 10 mg produced an increase in epinephrine concentrations 15 min after iv injection (186 +/- 23 vs 99 +/- 9 pmol/l, P less than 0.01). Since naloxone did not modify plasma levels of insulin and glucagon, an indirect effect of naloxone on adrenal medullary secretion seems to be excluded. These results are in agreement with in vitro experimental data obtained in animals and suggest that endogenous opiates also have a role in modulating adrenal medullary secretion in man.

Adrenal Medulla↗
PubMed1984

Quantitative and qualitative analysis of the relationship between exercise-induced R wave amplitude changes and severity of coronary artery disease.

The correlation between R wave voltage variations (delta R) and the angiographic severity of coronary artery disease (CAD) at progressively increasing heart rate (HR) steps was evaluated in 51 patients (pts) without CAD (OV), in 42 pts with single (SVD), in 43 with double (DVD) and in 59 pts with triple vessel disease (TVD). At the end of stress the sensitivity of delta R was higher in DVD and TVD pts than in SVD pts. There was no clear correlation between exercise-induced R wave changes and the angiographic severity of CAD, since the qualitative and quantitative delta R evaluation during effort showed similar changes in delta R for a wide range of HR's in the entire study population. Since different degrees of exercise tolerance were found in pts with SVD, DVD and TVD, we hypothesize that the correlation between delta R and the severity of CAD at the end of stress testing may be artifactual.

Analysis of Variance↗
PubMed1984

Effects of long-term molsidomine treatment versus isosorbide dinitrate and placebo on exercise tolerance in stable angina.

A single-blind study (n = 59) was performed to assess the effect of long-term (4 week) orally administered molsidomine (2 mg 4 X daily), isosorbide dinitrate (10 mg 4 X daily), and placebo on exercise tolerance performed on the bicycle ergometer by patients with stable angina on effort and with significant coronary artery disease. Isosorbide dinitrate had similar effects to placebo, both failed to modify the pressure-rate product, the sustained work load, and the ST segment depression, but slightly decreased, although not significantly, the incidence of angina. Although not affecting the pressure-rate product and the mean blood pressure, molsidomine decreased significantly the ST segment depression (p less than .05). In conclusion, by markedly reducing preload and because of its long-lasting effect (up to 6 h), the new vasodilator drug molsidomine plays a useful role in the long-term management of stable angina on effort.

Angina Pectoris↗
PubMed1984

[Relation between the QT interval and the severity of ventricular arrhythmias in the early phases of myocardial infarct].

The purpose of our research was to evaluate the relationship between the severity of ventricular arrhythmias in the first hours of myocardial infarction and the duration of electrical systole (QT). Twelve-lead resting electrocardiograms (ECGs) of 66 non-consecutive patients admitted to our Coronary Care Unit for myocardial infarction were retrospectively evaluated. Criteria for retrospective selection of patients were the following: 1) admission to the coronary care unit within 12 hours from the onset of myocardial infarction symptoms; 2) appropriate ECG changes suggesting acute transmural infarction (pathologic Q waves, envolving ST changes) and diagnostic elevation of serum enzymes activity; 3) good-quality ECG recordings with sinus rhythm and no conduction defects, recorded before the beginning of therapy and within the first hours after the onset of symptoms. After this first selection, the following criteria of exclusion were applied: 1) abnormal values of serum Ca++ and K+; 2) historical and/or electrocardiographic findings of a previous myocardial infarction; 3) chronic treatment with antiarrhythmic or beta-blocking drugs, digitalis or other drugs affecting the QT interval; 4) administration of drugs affecting the QT interval before admission; 5) clinical signs of left ventricular failure or cardiogenic shock at admission or during the hospitalization; 6) development of severe ventricular arrhythmias after 24 hours from the onset of symptoms. Three subgroups were individuated : group A: 39 patients with non life-threatening ventricular arrhythmias; group B: 12 patients with episodes of ventricular tachycardia within the first 12 hours of myocardial infarction; group C: 15 patients with episodes of ventricular fibrillation within the first 12 hours of myocardial infarction.(ABSTRACT TRUNCATED AT 250 WORDS)

Arrhythmias, Cardiac↗
PubMed1983

Plasma catecholamine response to orthostasis in longstanding hypothyroidism.

In seven normotensive women affected by long-standing hypothyroidism norepinephrine peripheral levels were found significantly higher than after replacement therapy and than normal controls. After standing norepinephrine peripheral concentrations increased further; such an increase, although percentually lower than after therapy was sufficient to assure an adequate clinical response to orthostasis.

Adult↗
PubMed1983

Exercise induced ventricular arrhythmias. Angiographic correlation with the severity of coronary artery disease.

We correlated the incidence and degree of exercise induced ventricular arrhythmias (EIVA) with the angiographic severity of coronary artery disease (CAD) in 162 patients with a history of stable effort angina, all showing a positive exercise stress test for myocardial ischemia and a greater than or equal to 70% stenosis of a major coronary artery. Patients were grouped according to the following criteria: presence of electrocardiographic evidence of old transmural myocardial infarction (MI), number of significant coronary stenoses and number of left ventricular (LV) areas showing abnormal segmental wall motion (ASWM). The incidence of EIVA in patients with multivessel CAD was higher than in patients with single vessel CAD, but this difference was not statistically significant. The number of LV areas with ASWM was better correlated with the frequency of EIVA, which was 20.0% in patients with normal LV wall motion, 31.2% in patients with 1 area of ASWM, 54.0% in patients with 2 areas of ASWM (p less than 0.005 vs normal LV wall motion), 74.1% in patients with 3 or more areas of ASWM (p less than 0.001 vs normal LV wall motion and 1 area of ASWM), and 81.8% in patients with LV aneurysm (p less than 0.001 vs normal LV wall motion and 1 area of ASWM, p less than 0.005 vs 2 areas of ASWM). Patients with old MI showed a significantly higher incidence of EIVA than those without MI (p less than 0.001), but this difference was due to the more severe LV asynergy in the MI group. In conclusion, our results show that, in a selected population of patients with CAD, the incidence of EIVA correlates better with the extent of LV segmental wall motion abnormalities than with the number of diseased coronary arteries or the presence of an old transmural MI.

Adult↗
PubMed1982

ATP and ADP content of human ejaculated spermatozoa. I. Relationship with semen physical parameters in normal donors and oligozoospermic patients.

ATP and ADP were measured by a bioluminescent method in human ejaculated spermatozoa from 31 normal donors and oligozoospermic patients. ATP and ADP expressed for the sperm total number were significantly correlated (P less than 0.001). ATP snd ADP levels were found significantly correlated with the total motile spermatozoa and with the total viable cells (respectively P less than 0.001 and P less than 0.001 for ATP and P less than 0.001 and P less than 0.001 for ADP). ATP/ADP ratio was found significantly lower in subjects with sperm motility less than 50% (P = 0.024) and total viable cells less than 80% (P = 0.026).

Adenosine Diphosphate↗
PubMed1982

ATP and ADP content of human ejaculated spermatozoa. II. Time-dependent changes after ejaculation.

ATP and ADP content of ejaculated spermatozoa of 7 donors were measured by a bioluminescent method within 24 h. The semen samples were kept at room temperature and at prefixed time were tested for motility and viability and extracted for ATP and ADP measurement. ATP pattern in relation to the time was studied with a mathematical model and the resulting curve showed a very high significance (P less than 0.001). ADP decrease with time was not significant and was variable among our subjects. The relationship between ATP decrease (%) and the decrease (%) of viability and motility was not linear, and till now no mathematical model has been found to express this phenomenon.

Adenosine Diphosphate↗