[Quantitative study of left ventricular function by two-dimensional echocardiography].

: The results of two dimensional echocardiography and cineventriculography in the calculation of left ventricular volumes and ejection fractions were compared. The study was performed experimentally in dogs and also in 12 patients with ischaemic heart disease. 25 measurements were performed in the animal: 19 basal and 6 measurements one hour after occlusion of the LAD. Reconstruction by Simpson's method showed good correlations with angiography (p less than 0,001) for enddiastolic volume (r = 0,94), end systolic volume (r = 0,97) and ejection fraction (r = 0,89). A preliminary clinical study was performed in 12 patients. All had significant stenosis of at least one main coronary artery and 10 had segmental abnormalities of left ventricular wall motion. Left ventricular volumes were calculated from the simplified 5/6 AL formula which only requires one long axis view and one short axis view at the level of the papillary muscles. The comparison between echocardiography and angiography showed a better correlation for end systolic volume (r = 0,91) than for end diastolic volume (r = 0,73). Echo underestimated end diastolic volume by 14% and end systolic volume by 13%. The correlation obtained for ejection fraction was excellent (r = 0,97) with no underestimation of this parameter by echocardiography. In conclusion, left ventricular volumes and ejection fractions may be calculated by two dimensional echocardiography. The technique allows a sequential quantitative study from beat to beat and in real time of cardiac function. It is a simple non-invasive method of following the evolution of cardiac disease and of assessing the effects of therapy on left ventricular function.