Relationship Between Echocardiography, Cardiac Output, and Abnormally Contracting Segments in Patients with Ischemic Heart Disease

Twenty-four patients with proven coronary artery disease and abnormally-contracting segments were studied by both echocardiography and biplane angiographic techniques. Comparison was made between the left ventricular biplane angiographic volumes and those obtained from echocardiographic measurements which were calculated from cubed function and regression equation methods. The percent abnormally contracting segment (ACS) was obtained from biplane left ventricular angiography and was calculated from the diastolic and systolic anteroposterior and lateral angiocardiograms. The angiographic end-diastolic volume correlated with that calculated from the echocardiographic dimensions with an r value of 0.865 and see of ± 22.64 ml. The angiographic end-systolic volume and echo end-systolic volume did not correlate as well, with an r = 0.7063. The difference in stroke volume predicted by the diastolic and systolic echocardiographic dimensions and the actual stroke volume determined by Fick technique was related to the percent abnormally contracting segment of the left ventricle (r = 0.8967). The percent ACS could be estimated from echo and Fick stroke volume measurements by the cube function and regression equations. Echo ventricular volume determinations were analyzed for the cube function method and the regression equations of Fortuin et al. and Teichholz and coworkers, with the method of Fortuin et al. producing the most sensitive relationship: % ACS = 0.32 (SVecho - SVFick)% + 8.9%. The correlation coefficient for the estimate was 0.8967 with a see of ± 4.78 %. In patients with coronary artery disease and abnormally contracting segments, echocardiography can provide reliable measurements of left ventricular end-diastolic volume but estimates of end-systolic volume are less accurate. If mitral regurgitation or a ventricular aneurysm can be excluded, the difference in echocardiographic and forward stroke volume by an independent method is related to the angiographic abnormally contracting segment, and this relationship permits estimation of the size of the abnormally contracting segment.