Changes in configuration of the ventricular chambers during the cardiac cycle

Cinefluorographic angiocardiography has been used to record the sequential changes in the size and shape of the right and left ventricular chambers and the external cardiac silhouette in dogs. Evidence is presented which indicates that (1) the left ventricle is usually filled more rapidly than it is emptied, (2) the diastolic size appears to remain remarkably constant during a major portion of the diastolic period and (3) residual blood remains within the ventricle at the end of systole.