无心跳供体心脏移植热缺血时限的实验研究

目的探讨未经药物预处理的无心跳供体心脏移植成功的热缺血时限。方法实验犬30只，供体和受体组各5只，对照组：心脏以0℃组氨酸-色氨酸-酮戊二酸溶液（histidine—tryptophan—ketogluarate solution，HTK）500ml主动脉根部灌注，心脏停跳后切取供心，置于0℃HTK液中保存2h；热缺血16min组：心脏缺氧停跳后热缺血16min．用0℃ HTK液500ml灌注冲洗冠状动脉，切取供心．置于0ccHTK液中保存2h；热缺血18min组：心脏缺氧停跳后热缺血18min，灌注及保存方法同热缺血16min组。以标准心脏移植方法行原位移植，监测供体心脏移植前后的血流动力学指标、心脏质量，测定心肌酶等指标，电镜观察心肌组织超微结构改变。结果心脏移植实验中对照组及热缺血16min组均可成功复跳、脱离体外循环辅助，血流动力学指标差异无统计学意义（P〉0．05）。热缺血18min组仅有2例可以脱机，与对照组及热缺血16min组相比，左心室舒张末期压升高、-dp／dtmax下降较明显．与对照组差异有统计学意义（P〈0．05），但与16min组比较，差异无统计学意义（P〉0．05），心脏质量及心肌酶明显升高（P〈O．05），电镜观察超微结构破坏明显。结论常温热缺血16min的供心有可能被成功用于心脏移植。

Time limit of normothermic ischemia in canine heart transplantation from non-heart-beating donors

Objectives To study the time limit of normothermic ischemia of non heart beating donors （NHBDs） hearts from hypoxic cardiac arrest and without donors pretreatment which could transplant successfully. Methods Thirty adult dogs were divided into control group, normothermic ischemia 16 min group and normothermic ischemia 18 min group （n=10 for each group, including 5 for donors and 5 for recipients, respectively）. In control group, cardiac arrest was induced by HTK solution （0℃, 500 ml） perfusion, canine heart was storied for 2 h with HTK solution at 4℃ ; in 16 min group, normothermic ischemia 16 min in situ after hypoxic cardiac arrest, canine hearts was perfused and storied for 2 h with HTK solution at 4℃ ; in 18 min group, normothermic ischemia 18 min in situ after hypoxic cardiac arrest, canine hearts was perfused and storied at 4℃ for 2 h with HTK solution. Then orthotopieal transplantation was performed. Hemodynamic changes, enzyme activities, and heart weight were examined. Results Control group and normothermic ischemia 16 min group could wean from cardiopulmonary bypass successfully; In normothermic ischemia 18 min group, only 2/5 could wean from cardiopulmonary bypass, LVEDP ascends and -dp/dtmax descends obviously, there are statistical variance （P〈0.05） compared with control group, enzyme, heart weight and uhrastructure get worse compared with other two groups. Conclusions NHBDs heart of normothermie ischemia 16 rain in situ after hypoxic cardiac arrest could transplante successfully.