NA+ H+ EXCHANGE INHIBITION IMPROVES POSTTRANSPLANT MYOCARDIAL COMPLIANCE IN 4-HOUR STORED DONOR HEARTS/

Na+/H+ exchange inhibitors have cardioprotective properties, The effec ts of the new Na+/H+ exchange inhibitor, HOE642 on myocardial function were assessed after transplantation of canine brain-dead and non-brai n-dead donor hearts preserved for 4 h. Four groups were studied: brain -dead donors: non-brain-dead donors; brain-dead donors and recipients treated with HOE642 (2 mg/kg); and treated non brain-dead donors and r ecipients, Donor hearts were stored in NIH2, At the end of 60 min repe rfusion after transplantation, pressure-volume curves were constructed . Biopsies were analysed histologically and ultrastructurally. Afterwa rds, weaning from cardiopulmonary bypass was accomplished. HOE642 impr oved compliance in hearts from both brain-dead and non-brain-dead dono rs. No differences in myocardial water content nor in myocardial perfo rmance were detected. No irreversible damage was seen ultrastructurall y, It is concluded that myocardial compliance after transplantation wa s improved by administration of HOE642. The use of this inhibitor migh t improve the current myocardial preservation technique for transplant ation. (C) 1998 The International Society for Cardiovascular Surgery.