LEFT-VENTRICULAR VOLUME FROM PAIRED BIPLANE 2-DIMENSIONAL ECHOCARDIOGRAPHY

To evaluate the applicability of two-dimensional echocardiography to left ventricular volume determination, 30 consecutive patients undergoing biplane left ventricular cineangiography were studied with a wide-angle (84°), phased-array, two-dimensional echocardiographic system. Two echographic projections were used to obtain paired, biplane, tomographic images of the left ventricle. We used the short-axis view (from the precordial window) as an analog of the left anterior oblique angiogram, and the long-axis, two-chamber view (from the apex impulse window) as a right anterior oblique angiographic equivalent. A modified Simpson's rule formula was used to calculate systolic and diastolic left ventricular volumes from the biplane echogram and the biplane angiogram. These methods correlated well for ejection fraction (r=0.87) and systolic volume (r=0.90), but only modestly for diastolic volume (r=0.80). These correlations are noteworthy because 65% of the patients had significant segmental wall motion abnormalities. The volumes determined from the minor-axis dimensions of M-mode echograms in 23 of the same patients correlated poorly with angiography.