Experimental Research Of Myocardial Protective Effect Of New Cardioplegia Solution

Cardioplegia solution is now used in a variety of open heart surgery under cardiopulmonary bypass and heart transplant surgery; the solution can provide effective myocardial protection, which greatly promoted the development of cardiac surgery. Based on the current seletion of cardioplegia solution during the operation and the research of myocardial protection at home and abroad, we have developed a new cardiaoplegia solution and make a comparative reseach with the HTK solution and St·ThomasⅡsolution which is widely used in cardiac surgery through the isolated rat heart Langendorff model and mini-pig open heart surgery under cardiopulmonary bypass model. The reseach is designed to further study the mechanism and the best ingredients of cardilplegia solution to enhance the myocardial protective effect.The research is divided into two parts; the first part is to conduct the isolated rat heart perfusion - cold storage - reperfusion experiment through the establishment of isolated rat heart Langendorff model to simulate the myocardial protection of the cardioplegia solution during the heart transplant surgery on the heart donor acquisition, preservation and transplantation processes. The experiment evaluate the effect of heart preservation of new cardioplegia solution, HTK solution and ST·ThomasⅡsolution from the hemodynamics (coronary flow, heart rate, left ventricular peak systolic pressure, left ventricular end-diastolic pressure, left ventricular developed pressure, cardiac work index, maximal rate of left ventricular systolic pressure, maximal rate of left ventricular diastolic pressure), myocardial enzymes (creatine kinase MB and cardiac troponin T), myocardial water content, coronary endothelial function (nitric oxide, endothelin-1), antiperoxidation (superoxide dismutase, malondialdehyde), myocardial adenosine triphosphate and myocardial pathological structure (light microscopy, electron microscopy). The results showed that the myocardial preservation effect of new cardioplegia solution was superior to or equivalent to HTK solution and ST·ThomasⅡsolution in all respects. The second part is to conduct the mini-pig open heart operation experiment through the establishment of mini-pig open heart surgery under cardiopulmonary bypass model to simulate the myocardial protection of the cardioplegia solution during the open heart surgery under cardiopulmonary bypass. The experiment evaluate the effect of myocardial protection of new cardioplegia solution, HTK solution and ST·ThomasⅡsolution from the hemodynamics, myocardial enzymes, myocardial water content, coronary endothelial function, antiperoxidation, and apoptosis in cardiomyocytes (apoptotic cell morphology, apoptotic cell positive rate and protein expression of apoptosis-related gene). The results showed that the myocardial protective effect of new cardioplegia solution was superior to or equivalent to HTK solution and ST·ThomasⅡsolution in all respects.Two experiments set up the in-vitro and in-vivo animal models to research the cardioplegia solution, tested the myocardial protective effect of isolated rat heart and mini-pig and got satisfied results. It will make a basis for followed research of cardioplegia solution.