Problems in echocardiographic volume determinations: echocardiographic-angiographic correlations in the presence of absence of asynergy.

The relation of minor and major axes of the left ventricle was determined in 100 left ventriculograms performed in the right anterior oblique projection. This relation taken over a wide range of volumes was used to derive a theoretically correct equation for determination of ventricular volume by echocardiography. The final equation was: V =[7.0/2.4 +d] (D3), where V = volume and D = the echocardiographically measured internal dimension. In 12 patients without asynergy, this equation accurately and directly calculated end-systolic and end-diastolic volumes whether the left ventricle was small or large. However, in 12 patients exhibiting left ventricular asynergy the correlation between angiographically and echocardiographically determined volumes was poor. Thus, caution is recommended in the use of time-motion echocardiography to calculate ventricular volumes in patients with coronary artery disease and possible left ventricular asynergy.