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Biomedical subjects

A Barsotti

Publications and source records attributed to A Barsotti.

At least 109 records · Page 6Linked to original sources
PubMed1992

[Myocardium-protective effects of phosphocreatine in experimental ischemia-reperfusion].

The protective effects of exogenous phosphocreatine were evaluated in vitro on isolated perfused rat hearts during reperfusion of ischemic myocardium. The hearts were randomly allocated in 2 groups. In the first (n 6) phosphocreatine was added at a concentration of 10 mM. The latter was utilized as control (n 7). In both groups the results showed a slight decrease in the post-ischemic myocardial performance. Aortic systolic pressure and flow respectively decreased on reperfusion by 17% and 12.5% in the phosphocreatine group and by 25.6% and 35% in the control group. Coronary flow was reduced by 10% in the phosphocreatine and by 18% in the control group. No statistically relevant differences were reported within or between the groups. No changes in heart rate occurred in the same period in the phosphocreatine and in the control group. Myocardial enzyme release during reperfusion showed significant lower levels of CK and LDH in the phosphocreatine group compared to controls (p less than 0.001 after 65 min and p less than 0.025 after 75 min between the 2 groups). The occurrence of serious ventricular arrhythmias was considerably higher in controls with respect to the phosphocreatine group. The overall incidence of major rhythm disturbances was 66% in the phosphocreatine group and 100% in the control group. Irreversible ventricular fibrillation (57%) occurred only in control hearts. The present findings indicate that phosphocreatine exerts a protective effect during myocardial ischemia and reperfusion, especially by preventing serious ventricular arrhythmias and by reducing myocardial enzyme release.

Animals↗
PubMed1991

Silent myocardial ischaemia: to treat or not to treat?

Silent myocardial ischaemia is now recognized with increasing frequency in patients with coronary artery disease. It is estimated to occur in 30-70% of patients with stable or unstable angina pectoris or with previous myocardial infarction, while, in totally asymptomatic healthy subjects, a prevalence of 2-4% is reported. However, these data must be evaluated with caution, because the predictive value of the tests employed in detecting silent ischaemia, depends on each test's sensitivity and specificity as well as on the prevalence of the disease in the evaluated population (Bayes's theorem). Available data suggest there is an important relationship between silent myocardial ischaemia, total ischaemic burden and adverse clinical outcome (non fatal myocardial infarction and cardiac death), especially in patients with documented coronary lesions. However, an elusive link between silent myocardial ischaemia and sudden cardiac death has currently been observed. Many reports have demonstrated that therapy with nitrates, beta-blockers and calcium channel blockers or revascularization procedures are effective in reducing silent myocardial ischaemia and its duration, but it remains unclear whether these treatments influence prognosis. A resolution of these uncertainties by controlled clinical trials will be necessary in order to choose therapeutic strategies, especially in totally asymptomatic subjects.

Arrhythmias, Cardiac↗
PubMed1991

[Modern trends in the therapy of arteriosclerosis in the light of new physiopathological findings].

In the last years, a plasmatic fibrinogen increase, a fibrinolytic system activity reduction and platelet activation, seemed to play a significant role on the genesis and progression of atheromatous plaques, especially when combined to a plasmatic lipoprotein increase. The results obtained in normolipidaemic patients (2000 asymptomatic subjects, 364 non-insulin diabetic patients randomly divided into 2 groups, treated and not treated with bezafibrate 400 mg/daily, 69 nifedipine-30 mg/daily-treated subjects, and 38 patients submitted to nifedipine-30 mg/daily-combined to indobufen-400 mg/daily-therapy), are reported. The results obtained in hyperlipidaemics (blood cholesterol level > 240 mg/dl; 356 patients, randomly divided into 2 groups, treated and not treated with bezafibrate 400 mg/daily, 56 patients with simvastatin 40 mg/daily and 85 with low saturated fat and low cholesterol diet), are also reported. Follow-up of all the patients was 4 years, but the simvastatin group followed-up only 1 year. An ultrasound examination of carotid and femoral arteries was performed in all the patients by means of a Duplex Scanner ATL Ultramark 5, with a high resolution probe (10 MHz). Subjects were graded into I-VI classes, according to the vessel progressive atherosclerotic impairment. In normolipidaemics, wall atheromatous changes were seen with increasing frequency with age, and a significant relationship among plaque progression rate and developed cerebrovascular symptoms, developed symptomatic peripheral symptoms, increased cardiovascular events and mortality rate, was evidenced. Non-insulin dependent diabetes, combined to normal levels of blood lipoproteins, appears an independent risk factor, superimposable to hyperlipidaemia. In this group of patients, bezafibrate therapy significantly reduced plaque progression, acting on blood coagulation factors and similar results were obtained in nifedipine and nifedipine plus indobufen groups. Also in hyperlipidaemics treated with diet, simvastatin and bezafibrate, the plaque progression was significantly reduced with respect to control group, especially when blood lipoproteins and coagulation were normalized. In conclusion, hyperlipidaemia, Ca++ and blood coagulation disorders, appear to be the main factors affecting the plaque progression, and the prevalence of each factor in the atheroma development must be well evaluated in the single patients to establish an adequate therapeutic strategies.

Adolescent↗
PubMed1991

"Ultrasonic biopsy"--a non-invasive screening technique to evaluate the cardiovascular risk and to follow up the progression and the regression of arteriosclerosis.

To determine the prevalence of atherosclerotic plaques in different age groups, an ultrasound examination of carotid and femoral artery bifurcations was performed in 2000 asymptomatic subjects with an age range of 10-93. Subjects were graded into classes A-F according to vessel wall characteristics: A) normal wall (intima media and adventitia clearly separated); B) interface disruption; C) intima-media granulation; D) plaque without hemodynamic disturbance; E) stenosing plaque (no symptoms); F) plaque + stenosis + symptoms. Atherosclerotic changes were seen with increasing frequency with age. Subclinical lesions were commonest in the 70-79 age group and 30% of these subjects were in D-E classes. A cardiac stress test was performed on 204 subjects in the 50-59 age group. The incidence of ischemic events in this group was 57.6%, the majority of these occurred in subjects in classes D-E. In a four year follow-up of 424 subjects, less than 1.9% showed a significant change in their global score. However, 47 early atherosclerotic lesions were seen to progress and 18 to regress. Over four years, 15% developed cerebrovascular symptoms and 18% developed symptomatic peripheral vascular disease. All these patients were in D-E classes at the beginning of the study. Cardiovascular events also occurred with increasing frequency in classes C-E (A + B = 0, C = 5.7%, D = 12%, E = 39.3%). Mortality rate was 4.8%, all patients being in classes D-E. In conclusion, high resolution ultrasound may be used for an arterial "ultrasonic biopsy". This technique can detect early atherosclerotic changes and can predict the risk of occult cardiac disease and the risk of developing symptomatic disease.

Adolescent↗
PubMed1987

Asynergy and left ventricular performance in dilative cardiomyopathy.

The purpose of this work was to evaluate the presence and importance of asynergy in dilative cardiomyopathy. A semiautomatized analysis of left ventriculograms was performed in 18 cases, the morphology of longitudinal and transverse axes time-length curves was evaluated, and mathematical indices of asynchrony and hypokinesis were defined. Ten normal subjects and 9 patients affected by aortic regurgitation were used as controls. In dilative cardiomyopathy, anomalous (polyphasic) time-length curves were present in 55% of the cases, while they were absent in aortic regurgitation and in all normal subjects but one. In addition, the asynchrony index was slightly increased and the hypokinesis index significantly increased (28.8 +/- 7.2% vs. 17.8 +/- 7.1%, p less than 0.001). A negative correlation existed between the asynchrony index and the ejection fraction (r = -0.483, p less than 0.05) and both the ejection fraction and the maximum normalized velocity of contraction were reduced in the patients with the anomalous curves (29.7 +/- 6.9% vs. 46.0 +/- 11.5%, p less than 0.01; 1.66 +/- 0.52 s-1 vs. 2.86 +/- 1.33 s-1, p less than 0.02). It was concluded that asynergy, and especially asynchrony, is frequent in dilative cardiomyopathy and it is strongly associated with a major impairment of overall left ventricular function.

Adolescent↗
PubMed1987

[Evaluation of a latex test for determining the fibrinogen/fibrin D-dimer (XDP)].

In this study an agglutination assay, by a monoclonal antibody coated latex particles, has been used for measuring specifically D-dimer fibrinogen/fibrin concentrations in twenty patients with various thrombotic diseases; the authors have analyzed the test reliability and the possible interferences caused by conditions of specimens collection and preparation.

Antibodies, Monoclonal↗
PubMed1982

Acute hemodynamic effects of Brescia-Cimino arteriovenous fistula for hemodialysis.

In ten uremic patients, who were not yet undergoing periodic hemodialysis and in whom we were creating a 1 cm, distal, side-to-side arteriovenous fistula of Brescia-Cimino type for hemodialysis, the acute hemodynamic changes of the systemic and pulmonary circulations were studied immediately after the opening of the fistula. An increase in cardiac output (Q) was observed in one patient, the other patients showing either no change or a slight reduction. In the four patients in whom the Q decreased there was a significant reduction of total blood volume (TBV) and stroke volume (SV) and an increase in systemic vascular resistance (SVR) (p less than 0.05, p less than 0.05, p less than 0.01 respectively). At the level of pulmonary circulation, in these patients a decrease in pulmonary blood volume (PBV) (mean = 20%) and a significant increase in pulmonary vascular resistance (PVR) were also observed. In five patients who had been on chronic hemodialysis and who presented the clinical picture of cardiac failure, the acute hemodynamic changes following temporary closure of the fistula (by a sphygmomanometer) were studied: a significant decrease (p less than 0.05) in Q, TBV and SV was observed. The difference between the two values of Q (i.e. fistula open and closed) was considered to indicate the magnitude of the flow across the fistula.

Adult↗
PubMed1980

Quantitative evaluation of the regional left ventricular function in normal subjects by means of cineangiocardiography.

A method for analysing left ventricular cineangiograms is described, which not only provides information on the overall ventricular performance, but also evaluates the regional contraction of the left ventricle and the related haemodynamic patterns. This simplified Chapman's method (slice method) makes it possible to calculate the end-diastolic, end-systolic volumes, the stroke volume and the ejection fraction of the zones into which the left ventricle is divided by a longitudinal and by three transverse axes, according to Herman's technique. The hemiventriculograms of 21 normal subjects in the AP projection were evaluated using this method and a 10 of them were also studied in RAO projection. A uniform left ventricular contraction pattern was found for three hemiventricles outlined by the anterolateral, lateral, and postero-medial walls (ejection fraction 71.7 +/- 5.1%, 71.6 +/- 5.9%, 70.4 +/- 5.1%, respectively), the regional and zonal ejection fraction (EFR, EFZ) being similar in both projections. The ejection fraction of the hemiventricle outlined by the septal wall was, however, lower (65.6 +/- 6.0%). The standard zonal function curves of the left ventricle in normal subjects was then calculated on the basis of the results obtained, in order to assess, by comparison, zonal function abnormalities in cardiac patients.

Adult↗
PubMed1977

[The quantitative cineangiography. Part II. Computerized analysis of the left ventricular volumes in man (author's transl)].

The values of left ventricular volumes (EDV and ESV) were determined in 35 patients with various heart diseases by computerized reading technique utilizying both the area-length and the slice methods. The data thus obtained were compared both with those derived manually and with those obtained following injection of 113mIn into the left ventricle and monitoring by external counting the dilution curve. Good agreement among the data obtained by the various methods was found. It appears, then, in the clinical practice, the computerized method has definite advantages over the others since it allows quick determination of the data and therefore examination of multiple frames.

Adolescent↗