Orthotopic transplantation of the canine heart after prolonged preservation by simple immersion.

The viability of the heart was assessed following orthotopic transplantation. Following coronary vascular washout with cold potassium-verapamil cardioplegia, the heart was removed, immersed in the same solution, and stored at 4 degrees C for 24 hours in Group I (6 animals), 36 hours in Group II (5 animals), and 48 hours in Group III (3 animals). All six animals in Group I and four of five animals in Group II maintained a stable recipient circulation for the acute phase of 2 hours after transplantation, without cardiopulmonary bypass. For the dogs in Group III, cardiopulmonary bypass was vital. Contraction band injury after transplantation was more frequently observed in the Group II grafts than those of Group I. We conclude that the combination of coronary vascular washout with cold potassium-verapamil cardioplegia and storage at 4 degrees C in the same solution may preserve the canine heart for up to 24 to 36 hours, as demonstrated by post-orthotopic transplantation function.