Experiences with a sac-type artificial heart.

A total replacement artificial heart is described having in vitro performance satisfying human requirements up to and including moderate work.The in vitro design has been modified to make its implantation into the chests of experimental animals technically feasible.The heart has been tested in vivo for up to six hours, and has been found to provide the experimental animals with adequate blood flow and pressures.Preliminary tests have shown major problems of air embolism and red blood cell hemolysis.The heart design and technique of implantation are undergoing further improvement. Performance will be more comprehensively examined with the use of larger experimental animals in order more accurately to evaluate the heart's potential.