Comparative Study Of Different Perfusion In Heart Graft Preservation In Rats

Objective: To compare the protection effect of different perfusion in isolated hearts of rats.Methods: Twenty-eight Sprague-dawley rats were randomized into four goups. Isolated hearts of rats were perfused in histidine-tryptophan-ketoglutarate(HTK) solution and underwent different 12-hour storage at 4 degree C. In group A(n=7), the isolated hearts soaked with HTK solution underwent cold static storage. In group B(n=7) and C(n=7), intermittent perfusion were performed in the cold storage period with HTK solution, and each perfusion was every 2 hours in group B and 4 hours in group C. In group D (n=7), low-flow rate continuous perfusion were performed with HTK solution in the cold storage period. Before and after hypothermic storage it was followed by 5 min of normothermic reperfusion on modified Langendorff-Neely model. The recovery rate of cardiac function and coronary sinus flow(CSF), the changes of CK, LDH, NO and ET were measured. The myocardial moisture capacities were examined. The samples of heart were observed through light microscope and cell apoptosis were detected by TUNEL staining.Results: After long-time hypothermic storage, significantly more recovery of cardiac function were noted in group B and D than those in group A and C, so were the changes of CSF. The leakage of CK, LDH, and the cell apoptosis in group B and D were significantly lower than those in group A and C. Protection of vascular endothelium in group B and D were better than those in group A and C. There were no significantly different in myocardial moisture capacities in 4 groups.Conclusions: Both continuous perfusion and intermittent perfusion are optimal means in isolated heart preservation with the support of HTK solution. They provide better myocardial protection than cold static storage without increasing myocardial edema. In intermittent perfusion means, interruption time can influence the effect of myocardial protection.