COLD-STORAGE OF THE HEART WITH UNIVERSITY-OF-WISCONSIN SOLUTION AND 2,3-BUTANEDIONE MONOXIME - LANGENDORFF VS ISOLATED WORKING RABBIT HEARTMODEL

Currently, for clinical heart preservation with University of Wisconsi n (UW) solution the ischemic time is limited to 8 h. The reliable pres ervation of the heart for 24 h or more would have a dramatic impact on the existing practice of cardiac transplantation. We showed previousl y [J. Thorac. Cardiovasc. Surg. 107; 764-775 (1994)] that experimental ly preservation could be extended to 24-30 h by preventing ischemic co ntracture of the heart with 2,3-butanedione monoxime (BDM) in the UW s olution (UWBDM). This resulted in nearly 100% return of function as te sted in the isolated crystalloid-reperfused rabbit heart in the nonwor king Langendorff preparation. We have confirmed these results and now have measured the function of hearts stored in UWBDM for 2, 4, 12, and 24 h using the isolated working rabbit heart model. Preservation in U WBDM solution resulted in a biphasic decrease of cardiac output. In th e hearts preserved for 2-12 h the decrease of function averaged 20-35% upon reperfusion, and the differences at 2, 4, or 12 h were not signi ficant (analysis of variance p > 0.05). A more pronounced decrease of 64% was obtained after 24 h of cold storage. Hearts preserved for 24 h without BDM were practically nonfunctional. The release of enzymes (c reatine kinase and lactate dehydrogenase) followed biphasic pattern si milar to that of cardiac output: a small release between 2 and 12 h an d larger, significant losses at 24 h. Although we originally proposed that hearts preserved with UWBDM for 24 h were well preserved (Langend orff model), we now show that poor function was obtained at 24 h. The difference was that in this study we used a more rigorous, isolated wo rking rabbit heart model to test the function of the preserved heart, and this may be a better test of preservation quality. (C) 1996 Academ ic Press, Inc.