Search PubMed⌕ Search

Biomedical subjects

R Prasquier

Publications and source records attributed to R Prasquier.

27 records · Page 2Linked to original sources

Study of left ventricular pressure-volume relations during nitroprusside infusion in human subjects without coronary artery disease.

Studies were made on 21 patients, 8 without any symptoms of left ventricular failure, group 1, and 13 with clinical symptoms of heart failure, group 2. Cardiac output, mean aortic and left ventricular pressures (using catheter tip micromanometer), and ventricular volume (obtained from left ventricular cineangiograms) were measured before and during nitroprusside infusion. The heart rate did not change in either of the groups. Only in group 2 did cardiac index and stroke volume increase significantly. Mean aortic pressure and total systemic vascular resistance decreased significantly in both the groups. Left ventricular end-diastolic pressure decreased significantly in both the groups, but this decrease was greater in group 2 (9 mmHg compared with 3 mmHg for group 1). The decrease in the left ventricular end-diastolic volume was similar in both the groups. The decrease in left ventricular end-systolic pressure was greater in group 1, but the decrease in the left ventricular end-systolic volume was greater in group 2. These facts are explained by the differences in the active and passive left ventricular pressure-volume relations in the two groups.

Adult↗

Acute mitral valve obstruction during infective endocarditis.

Five patients were found during surgery or at necropsy to have the mitral valve orifice obstructed by vegetations. They had had unexplained severe and recurrent episodes of acute febrile pulmonary oedema, and four had few cardiac ausculatory findings. Three patients died suddenly and unexpectedly; the other two were operated on and survived. In view of its ominous prognosis, acute mitral valve obstruction should be considered in patients whose pulmonary symptoms are compatible with endocarditis and are not adequately explained by the findings on examination of the heart. The condition, which should be confirmed by echocardiography, requires emergency surgery.

Adolescent↗

Occurrence and significance of echocardiographically demonstrated tricuspid valve prolapse.

Echocardiograms from 562 patients were examined for evidence of the pattern of tricuspid valve prolapse. Criteria for the diagnosis can be established similar to those applicable to mitral prolapse. In 500 consecutive patients without mitral valve prolapse, there were no cases of isolated tricuspid valve prolapse. Eleven of 53 (21%) patients with mitral valve prolapse also had tricuspid valve prolapse. Four of six (67%) patients with Marfan's syndrome and mitral valve prolapse also had tricuspid valve prolapse. The occurrence of this echocardiographic pattern as an isolated finding as well as associated with mitral valve prolapse was significantly less than previous angiographic reports. Patients with both these findings tended to be older than those with mitral valve prolapse alone, but clinically differed in no other way. Use of standardized technique can minimize errors in diagnosis.

Adolescent↗

The specificity of the diffuse pattern of cardiac uptake in myocardial infarction imaging with technetium-99m stannous pyrophosphate.

To analyze the specificity of the diffuse pattern of cardiac uptake with technetium-99m stannous pyrophosphate (TcPYP), we evaluated the bone scans of 1,383 noncardiac patients and the myocardial scintigrams of 120 cardiac patients. Seventy (14.4%) of 483 bone scans performed on a scintillation camera revealed diffuse TcPYP cardiac uptake. Among the total 603 camera bone scans and myocardial scintigrams, the incidence of diffuse cardiac uptake was 16% among patients with clinical coronary disease but 13% among those patients without clinical symptoms. Discrete myocardial uptake was seen in 25 of 26 patients with transmural infarction. Femoral vasculature was more frequently visualized (84% vs 3%, P less than 0.001) and left mastectomy occurred more often (30% vs 1%, P less than 0.001) among patients with diffuse cardiac uptake than among patients with negative images, indicating possible blood pool imaging. The diffuse pattern of cardiac uptake appeared nonspecific and may be due to unintentional cardiac blood pool imaging.

Bone and Bones↗

Cardiac output measurement with a simplified thermodilution technique. Comparison with the Fick method.

A simplified thermodilution technique for cardiac output measurement is compared with the Fick method in dogs, over a wide range of cardiac output values. The reproducibility of the method is satisfactory (differences less than 10 per cent for 95 per cent of the measurements). The overall correlation factor (r = 0.97) is highly significant for cardiac outputs ranging from 750 to 7,500 ml.mn(-1). The influence of hematocrit (when lower than 30%) and of the injection site of indicator are discussed. Present experiments confirm that the use of pre-set factors allow for the thermal loss inside the catheter does not obviate the accuracy of thermodilution method for cardiac output measurements. The slope of the regression line is very close to 1. Lack of fit to linearity is tested and is found not significant throughout the explored range. This technique should therefore have extensive clinical applications.

Animals↗