The effects of the hypothermic management of brain dead dogs on preserving graft viability in heart transplantation.

The effect of hypothermic management for brain dead dogs on preserving graft viability was evaluated through preservation and transplantation. After the occurrence of brain death, 43 dogs were divided into two groups; the normothermic group (37.2+/-0.3 degrees C) and the hypothermic group (31.8+/-0.3 degrees C) according to the esophageal temperature. After the 6-hour management of brain dead donors, the heart beat was arrested using a cardioplegic solution followed by coronary vascular bed washout. The donor heart was then harvested and preserved for 12 hours with simple immersion into the University of Wisconsin solution. Following preservation, orthotopic transplantation was performed in six grafts randomly selected from each group. During the 6-hour management of brain dead dogs; 1) heart rates, rate-pressure products, and the total amount of catecholamine were significantly (p<0.05) lower in the hypothermic group than in the normothermic group, and 2) lactate contents collected from the coronary sinus blood and O2-extraction rates of the heart tended to be lower in the hypothermic group than in the normothermic group. During 12 hours of preservation, intracellular pH and creatine phosphate contents were higher in the hypothermic group than in the normothermic group. Following orthotopic transplantation, the animals in the hypothermic group showed a significantly (p<0.05) higher recovery rate of left ventricular (LV) pressure and the maximum rate of the rise of LV pressure compared with normothermic group animals. We conclude that the hypothermic management of brain dead dogs may be effective in preserving graft viability and may provide a clinical application for heart transplantation with acceptable outcomes.