[Successful ex vivo preservation of canine hearts for 24 hours].

Prolonged storage of hearts in a viable condition is one of the most important problems of cardiac transplantation. Recently we have developed the new perfusion system and succeeded in preserving hearts extracorporeally for 24 hours in beating condition. In this series nine canine hearts were preserved for 24 hours by this perfusion method. Three of them were only for preservation and six were transplanted orthotopically into the recipient dogs after 24 hours preservation. These hearts were examined by light and electronmicroscopy at the different stages, namely after 24 hours preservation, at 24 hour after transplantation, on 7th day after transplantation. The morphological study demonstrated that myocardium showed no evidence of structural damage. This perfusion system is newly developed and one step to the clinical use for long-term heart preservation.