温缺血时间与同种心脏瓣膜细胞活性的关系

Study of Relationship between Warm Ischemia Time and Homograft Valve Viability

以１０具脑外伤死亡的健康男性的心脏的６０个同种主动脉、肺动脉瓣叶分为６组进行实验。经不同的温缺血时间灭菌并经过３个月的液氮深低温保存后，通过流式细胞计数测定细胞活性，同时行组织块贴壁培养及电镜观察。结果表明：温缺血时间在１２小时以内，细胞活性为９３．４９±２．３５％，较对照组无明显下降。灭菌２４小时，细胞活性为８９．８２±３．５２％，较对照组明显下降，Ｐ＜０．０１，并且可见形态上改变；冷冻后细胞活性进一步下降，但下降幅度减低，冻存３年后活细胞仍占８０％。结论为：温缺血时间对细胞活性有影响，时间延长与活性的下降成正相关。因此温缺血时间应控制在１２小时以内。

Aim:To study the relationship between warm ischemia time (WIT) and cells viability of valve homografts.Method:Sixty aortic or pulmonary valve leaflets were divided into 6 groups according to different WIT.The WIT ranged from 0 to 24 hours.Cells viability were assessed by using flow cytometry and electron microscopy.Result:The viability of cells was correlated to WIT.With 12 hours of warm ischemia,93.4±3.52% of cells were viable,but there was no significant decrease as compared with control group.After 24 hours of warm ischemia,89.8±3.52% of cells were viable,the decrease in cells viability was significant ( P <0.01).The viability continued to decrease after cryopreservation,but it slowed down with time.Conclusion:The viability of cells are correlated to WIT.Long WIT reduces the viability of cells.The result indicates that a WIT less than 12 hours is a safe time for preservation of viability of cells of valve homograft.