Angiocardiographic right ventricular volume determination. Accuracy, as determined from human casts, and clinical application.

On the basis of 22 life-like human casts (the method is described in the first paper of this series) the influence of (a) spatial orientation, (b) cardiac-phase and (c) biplane (BP) and single-plane (SP) methods of volume calculation on the accuracy of right ventricular (RV) angiocardiographic volume determination was quantitated. The best results are obtained, when a BP approach is utilized and when position and cardiac-phase appropriate correction factors (CF) are applied to the model volumes (multiple-slices (MS) and area--length (AL) methods). Thus the statistical error is decreased and a more important larger systematic error (especially for SP) avoided. The MS and AL methods perform equally well; on the average, however, the MS method is slightly favored. The application of this concept of differentiated CFs to 100 normal right ventricles of infants and children resulted in nonlinear relationships between RV volumes and their respective body surface areas (BSA) (EDV = 73.1 . BSA1.219, r = 0.961,SV = 46.2 . BSA1.219, r = 0.937). The ejection fraction (63.3%) does not correlate with the BSA (r = -0.292). The right ventricle accomplishes the same SV (with respect to BSA) as the left ventricle from a higher enddiastolic and endsystolic level.