Transapical left ventricular bypass for infants and newborns: an acute experiment using dogs.

This study was designed to extend the clinical indications of ventricular bypass to infants and newborns with severe left ventricular failure. The circuit is composed of 8-mm polyvinyl chloride tubing, microfilter, local heparinization circuit, and outflow-withdrawal cannulas of 10F to 20F. Filling capacity is 150-270 ml. In acute nonpulsatile left ventricular bypass experiments using six dogs weighing 3-7 kg, a bypass equivalent to 100% of the cardiac output prior to bypass could be attained in both normal and induced failure model of heart. Through left ventricular bypass the effects of left ventricular support such as marked reduction of LVP, LVmax dp/dt, and TTI were observed.