Lu J H, Chang Y, Hsu W H, Hwang B, Chong C K, Wu C C, Yang P Z, Hsing-Wen H
Division of Pediatric Cardiology, Veterans General Hospital-Taipei, National Yang-Ming University, Taiwan, Republic of China.
Ann Thorac Surg. 1998 Jan;65(1):24-7. doi: 10.1016/s0003-4975(97)00913-2.
The injury resulting from postmortem ischemia is a critical deterrent to the availability of donor valves. Using the reduction of XTT-tetrazolium salt as a marker of metabolic sequelae, we assessed the injurious effect of ischemia and the metabolic sequelae in 156 porcine semilunar leaflets.
The leaflets were randomly allocated to noncryoprocessed (n = 72) or cryoprocessed (n = 72) groups. At each preservation temperature of 4 degrees C, 24 degrees C, or 37 degrees C, 24 leaflets each were exposed to one of four storage periods of 9, 17, 30, or 60 hours. Twelve fresh aortic leaflets served as baseline reference samples.
There was a progressive loss in the metabolic functioning of valve leaflet cells in both noncryopreserved and cryopreserved tissue as the storage times increased. Cryopreserved tissue showed a greater loss of function than noncryopreserved tissue did. The metabolic injury was mainly a consequence of cryoprocessing. The greatest loss in metabolic functioning occurred in the valves stored for 60 hours. The least favorable combination of variables was cryopreservation and a precryopreservation storage time of 60 hours.
We conclude that 30- to 60-hour delays do not have a significant metabolic effect on cardiac leaflets. Thus it may be possible to safely extend the permissible ischemic periods after organ harvest.
尸检缺血导致的损伤是供体瓣膜可用性的关键阻碍。我们以XTT四氮唑盐的还原作为代谢后遗症的标志物，评估了156个猪半月瓣叶缺血的损伤效应和代谢后遗症。
将瓣叶随机分为未冷冻处理组（n = 72）和冷冻处理组（n = 72）。在4℃、24℃或37℃的每个保存温度下，每组24个瓣叶分别暴露于9、17、30或60小时这四个保存时间段之一。12个新鲜主动脉瓣叶用作基线参考样本。
随着保存时间的增加，未冷冻保存和冷冻保存组织中瓣叶细胞的代谢功能均逐渐丧失。冷冻保存组织的功能丧失比未冷冻保存组织更严重。代谢损伤主要是冷冻处理的结果。代谢功能丧失最大的情况发生在保存60小时的瓣膜中。最不利的变量组合是冷冻保存和冷冻前60小时的保存时间。
我们得出结论，30至60小时的延迟对心脏瓣叶没有显著的代谢影响。因此，有可能安全地延长器官获取后的允许缺血时间。
