EVALUATION OF HYPOTHERMIC HEART PRESERVATION WITH UNIVERSITY-OF-WISCONSIN SOLUTION IN HETEROTOPICALLY AND ORTHOTOPICALLY TRANSPLANTED CANINE HEARTS

In simple cold storage of the heart, 4 hours has been proved to be a clinically safe ischemic time. The University of Wisconsin solution has been reported to extend cold ischemic time in preservation of the liver, kidney, and pancreas. The purpose of this study is to clarify the safe cold ischemic time in heart preservation with University of Wisconsin solution experimentally in heterotopically and orthotopically transplanted canine hearts. In heterotopic heart transplantation, 120 minutes after reperfusion, maximum slope of the left ventricular end-systolic pressure-volume relationship was recovered to 94% +/- 13% in the 4-hour simple cold preservation group with GIK solution and 104% +/- 11% in the 8-hour simple cold preservation group with University of Wisconsin solution but was not recovered in the 8-hour simple cold preservation with GIK solution and 16-hour simple cold preservation with University of Wisconsin solution groups. One hundred twenty minutes after reperfusion, myocardial tissue blood flow measured by laser Doppler flowmeter was recovered to 90% +/- 19% after 4 hours with simple cold preservation with GIK solution and 98% +/- 9% after 8 hours with simple cold preservation with University of Wisconsin solution but was not recovered after 8 hours with simple cold preservation with GIK solution and 16 hours with simple cold preservation with University of Wisconsin solution. One hundred twenty minutes after reperfusion, serum creatine phosphokinase levels (international units per liter) after 4 hours with simple cold preservation with GIK solution and 8 hours with simple cold preservation with University of Wisconsin solution were lower than those after 8 hours with simple cold preservation with GIK solution and 16 hours with simple cold preservation with University of Wisconsin solution. One hundred twenty minutes after reperfusion, mitochondria in electron microscopic study were normally preserved after 4 hours with simple cold preservation with GIK solution and 8 hours with simple cold preservation with University of Wisconsin solution. In orthotopic heart transplantation, 120 minutes after reperfusion, cardiac output, left ventricular maximum rate of pressure rise, maximum slope of the left ventricular end-systolic pressure-volume relationship, and external work/pressure volume area efficiency recovered by dobutamine (10 mug/kg/min) administration after 4 hours with simple cold preservation with GIK solution and 8 hours with simple cold preservation with University of Wisconsin solution. These results suggest that use of University of Wisconsin solution for heart preservation extends the safe cold ischemic time up to at least 8 hours but not up to 16 hours. In simple cold storage of the heart, 4 hours has been proved to be a clinically safe ischemic time.