Search PubMed⌕ Search

Biomedical subjects

B Magnani

Publications and source records attributed to B Magnani.

At least 307 records · Page 17Linked to original sources
PubMed1979

[Left ventricular volume measurement; the accuracy of the measurement].

Volume angiography is a widely diffused technique in hemodynamic laboratories despite several factors which limit the validity of the method. We have evaluated three of these factors: a) indefiniteness in the identification of the contour of the left ventricular cavity on the projected image; b) indefiniteness due to the reproducibility in tracing the contour of the left ventricular cavity by the same operator; c) indefiniteness related to the geometrical assumption (ellipsoid of revolution). The indefiniteness, given as per cent variation from the mean value, has been determined for the diastolic as well as systolic phase. The maximal possible indefiniteness, for diastole and systole, in contours identification in 15 cases has been found to be +/- 11.3% and +/- 24% of the mean volume. Intra observer reproducibility evaluated outlining 30 times the left ventricular contour has been equal to a mean difference from the mean volume of +/- 1.2% for diastole and +/- 4% for systole. The mean difference of the mean volume calculated with the area-lenght method (ellipsoid geometry) from the volume calculated with the Simpson rule has been, on 15 cases, equal to 4% in diastole and 11% in systole. This high level of indefiniteness, mainly for the systolic phase, must be considered before giving a value excessively precise to the volume data obtained with angiography. On the other hand, the method retains an orientative meaning extremely useful in clinical evaluation.

Angiocardiography↗
PubMed1978

Effects of chlordane and heptachlor on the marine dinoflagellate, Exuviella baltica, Lohmann.

Chlordane and heptachlor at 50 microgram/1 reduced cell density, chlorophyll a per unit volume of culture, 14C uptake per cell and carbon fixation per unit of chlorophyll a in the marine dinoflagellate Exuviella baltica Lohmann. The concentration of chlorophyll a per cell was not reduced, however, by treatment with either compound. Chlordane was more toxic than heptachlor at this concentration, and caused the disintegration of many cells, thus affecting particle size distribution in the cultures. In nature, such an inhibition and shift in size class distribution could affect the availability of food for particle-feeding herbivores.

Chlordan↗
PubMed1978

[Hemodynamic effects of disopyramide and procainamide in open-chest animals].

Hemodynamic effects of two antiarrhythmic agents, disopyramide and procainamide, have been evaluated in anesthetized open-chest healthy pigs after random administration. At therapeutic plasma concentrations none of these agents proved to have deleterious hemodynamic effects. The most important action was observed after disopyramide infusion and consisted in significant bradycardia which confirmed the known effect on sinus node automaticity of the drug. Left ventricular dp/dt, an index of cardiac contractility, was unchanged after infusion of both drugs. On the ECG intervals, only procainamide provoked a significant prolongation of QTc. It is concluded that at therapeutic dosage disopyramide does not present deleterious hemodynamic effects in animals and proves to be a valid alternative to other traditional antiarrhythmic agents.

Animals↗
PubMed1978

[Evaluation of the radiological exposure for medical terms involved in haemodynamic examinations (author's transl)].

The radiation exposure of the medical team involved in 35 consecutive cardiac catheterisation procedures performed at the Istituto di Malattie dell'Apparato Cardiovascolare, University of Bologna, was calculated. A mapping of the iso-exposure lines and the values of radiation exposure of each component of the team were determined for each procedure. With these parameters the total amount of radiation for a normal diagnostic activity coul be calculated. The mean values obtained (150-250 mR/week) were in the range of the maximal values permitted to medical teams professionally exposed to the risk of radiation (3R/13 weeks). Rotation of the components of the team granted a continuing diagnostic activity within the limits of radiation exposure imposed by the law. An evaluation of the different procedures and techniques indicated coronary arteriography as the procedure with a higher risk of radiation (M = 50 mR/procedure) and pointed out the mechanism involved in order to obtain a considerable reduction of radiation exposure.

Cardiac Catheterization↗
PubMed1977

Haemodynamic effects of dobutamine in patients with coronary artery disease.

The haemodynamic effects of the infusion of dobutamine in dosages of 2-5, 5-0 and 10-0 mug/kg/min were studied in twelve patients with coronary artery disease. At the lowest dose, infusion of dobutamine caused a significant increase in cardiac output; greater increases occurred with doses of 5-0 and 10-0 mug/kg/min. The means by which the myocardium produced the increase in cardiac output differed according to the dose of the drug; 2-5 and 5-0 mug/kg/min produced an increase in stroke volume without any significant variation in the heart rate. At the highest dose rate, an increase in heart rate made a distinct contribution to the overall increase in output. The ventricular dp/dt max. increased at all three dosages. Blood pressure, pulmonary arterial and capillary pressure, and left ventricular and diastolic pressure did not show any significant change. The separation of the inotropic and the chronotropic effects of dobutamine according to the infused dose appears to have extremely interesting clinical implications.

Aged↗
PubMed1977

[Electrocardiogram in pulmonary embolism].

The Authors are examining the electrogenetic and vectorial alterations during pulmonary embolism and the consequent more frequent electrocardiographic patterns according to the literature data. The analysis of the electrocardiograms of 37 patients with proved pulmonary embolism confirms that ECG is not of absolute diagnostic value but may be extremely useful especially if subsequent records are compared.

Electrocardiography↗