The Study Of Pig Donor Hearts Preserved With Continuous Perfusion Of Normothermic Oxygened Blood

Part 1 The Ex vivo hearts model Preserved with continuous perfusion of normothermic oxygened bloodObjective: The aim of this study was to set up the model of animal which provided the basic research of organ care system in beating status with continuous perfusion of normothermic oxygened blood, and master the critical experimental details. Meanwhile it was to evaluate whether this preservation is better than cold storage.Methods: Zhonghua miniature pigs weighted 30±3 kilogram were randomly divided into two groups : Ex vivo heart perfusion group(group MP), four pigs;cold storage group(group CS), two pigs.The hearts in group MP were arrested by ST.Thomas solution at 4 ℃and preserved in Beating status for 8 hours with continuous perfusion of normothermic oxygened blood. Heart rate was monitored during the process of perservation. The Temperature,PH, partial pressure of oxygen, carbon dioxide partial pressure and the value of serum potassium, serum sodium and serum calcium were monitored with continuous arterial blood gas analyzer(CDI500). Hourly blood samples were taken for arterial blood gases, random blood sugar analysis and Activated Clotting Time. The Group CS heart were arrested by the Celsior solution at 4℃, were stored in Celsior solution(Celsior Flushing and cold storage solution for solid organ preservation solution) for 8 hours at 4℃.After 8 hours the myocardial tissue of left ventricular were observed with the light microscope, and the endocardial tissue of left ventricular were observed with the SEM(scanning electron microscope).Results:1 The donor hearts in group MP rebeated automaticly, storaging for 8 hours in beating status.2 The Ex vivo heart perfusion group cardiac muscle fibers with the light microscope were neater.3 The myocardial ultrastructure was observed with the SEM. The muscle fibers of the Ex vivo heart perfusion group were neater, the structure were neat and clear. Mitochondria was clear. The mitochondria of the cold storage group increased and gathered.Conclusions: Preservation of donor hearts for eight hours in beating status with continuous perfusion of normothermic oxygened blood is an effective method. This way can extend the saving time of donor hearts and can be more effective. Part 2 The study of myocardial ultrastructure and apoptosis of donor heart stored with Ex vivo perfusion and cold crystalloid storageObjective: This study is about the preservation of donor hearts for eight hours with continuous perfusion of normothermic oxygened blood comparing with the study that the donor hearts were preserved with cold Celsior solution. It could evaluate whether the perfusion group were better than the cold storage group.Methods: 12 Zhonghua miniature pigs were randomly divided into two groups : Ex vivo heart perfusion group, six pigs, the hearts were preserved in Beating status for 8 hours with continuous perfusion of normothermic oxygened blood; The cold storage group, six pigs were stored in Celsior solution for 8 hours at 4℃. The myocardial tissue of left ventricular were observed with the light microscope, and made the tissues into wax blocks, cut into thin slice. The measurement of the cardiomyocyte apoptosis were obtained by the way of TUNEL(Terminal-deoxynucleoitidyl Transferase Mediated Nick End Labeling).The endocardial tissue of left ventricular were observed with the SEM.Results: The myocardial ultrastructure were observed with the SEM,the muscle fibers of the Ex vivo heart perfusion group was neater, the structure was neat and clear. The mitochondria of the Ex vivo heart perfusion group was complete. Lysosome was less than the cold storage group’s. The measurement of the cardiomyocyte apoptosis obtained by the way of TUNEL was as follows: the apoptosis index of cardiomyocyte apoptosis in the Ex vivo heart perfusion group less than the cold storage group.Conclusions: Preservation of donor hearts for eight hours with continuous perfusion of normothermic oxygened blood could relieve the myocardial injury and enhance the function of donor heart comparing with the cold preservation group.