Critical review of recent work on ventricular diastolic suction.

Unequivocal evidence in favor of the concept that a ventricular diastolic vis a fronte contributes to ventricular filling has been established only in the following conditions: a. When the ventricle contains an abnormnlly small residual volume (rat, dog, turtle) ; b. When the ventricle contains a more nearly normal, residual volume due to ejection against the resistance of a fluid column (dog, turtle). The quantitative contribution of the ventricular vis a fronte to ventricular filling at various residual volumes and various levels of cardiac activity is still unknown. The physiological significance of diastolic suction for the return flow of blood can therefore not yet be evaluated.