Measurement of Left Ventricular Volume in the Canine Heart by Biplane Angiocardiography: Accuracy of the Method Using Different Model Analogies

Abstract
Casts of the left ventricular cavity were made in 21 canine hearts. Fifty observations were made by means of biplane X-ray films. Left ventricular volume was measured by water displacement and calculated according to six different model analogies. There was good statistical correlation and small error for each of the methods. Method 1, based on the use of the ellipsoid as the reference figure, and using the projected area and the long axis to calculate the transverse diameter, was more accurate than the others. The standard error of estimate with this method was 2.5 ml or approximately 8% at a volume of 30 ml, an average end diastolic volume for a dog weighing 15 kg.