The effects of orientation on volume measurements of human left ventricular casts.

Biplane angiocardiography has emerged as a standard method for calculating left ventricular volume measurements. Validation of such measurements has separately been made for several projections of silicone casts of the left ventricle. This study was undertaken to establish and compare the regression lines for left ventricular cast volume measurements in the commonly used angiographic projections. Once established, any ventricular volume can be calculated from the slope and intercept of the regression line obtained from the appropriate angiographic projection.