体外膜肺氧和对急性心肌梗死合并心源性休克猪模型的早期心肌保护作用

摘要

目的 通过建立急性心肌梗死合并心源性休克的小型猪模型,探讨静脉-动脉体外膜肺氧和(VA-ECMO)支持治疗对于小型猪的早期心肌保护作用.方法 24头雄性巴马小型猪随机分为对照组(A组)、药物治疗组(B组)、ECMO组(C组)3组.通过结扎前降支的方法,在药物治疗组及ECMO组建立心肌梗死模型.当小型猪出现休克时,非对照组开始进行药物治疗或者ECMO支持治疗,并在24h后,处死实验动物.观察各组左心室舒张末期压力(LVEDP)、左心室收缩期和舒张期压力变化率(LV±dp/dt)以及心肌酶谱等指标,并进行比较.结果 心肌梗死后6h,C组LVEDP开始显著低于B组(P＜0.05),并且随着实验时间的延长,差异越显著.实验结束前,各组LV-dp/dt差异均有统计学意义(均P＜0.05),即LV-dp/dt的下降,A组＜C组、B组;A组LV+dp/dt与C组及B组比较差异均有统计学意义(均P＜0.05);但C组LV+dp/dt与B组相比,在实验24h时差异无统计学意义(P＞0.05).C组与B组相比,心肌梗死面积无显著减小(P＞0.05),但心肌酶及肌钙蛋白Ⅰ显著降低(均P＜0.05).结论 ECMO能够显著改善心肌梗死后心源性休克猪模型的左心室舒张功能,可能改善左心室收缩功能.此外,ECMO并不能减少心肌梗死面积,但可能对缺血非梗死区细胞产生正面的作用,避免其进一步受损.%Objective To investigate myocardial protection effect of extracorporeal membrane oxygenation (ECMO) for acute myocardial infarction with cardiogenic shock in pigs.Methods Twenty four male pigs were randomly divided into three groups:control group,drug therapy group and ECMO group.Myocardial infarction model was induced in drug therapy group and ECMO group by ligating coronary artery.When cardiogenic shock occurred,drugs were given in drug therapy group and ECMO was perfored in ECMO group.The pigs were sacrificed 24 h after cardiogenic shock.The left ventricular end-diastolic pressure (LVEDP) and left ventricular pressure change in systolic and diastolic period(LV ± dp/dt) were observed;the myocardial enzymes were measured and compared among three groups.Results Compared with drug therapy group,the LVEDP in ECMO group decreased significantly 6 h after ligation (P＜0.05).At the end of the experiment,the LV-dp/dt of control group was higher than that of drug therapy and ECMO groups,while there was no significant difference between ECMO group and drug therapy group.Compared with drug group,myocardial infract size of ECMO group did not reduce significantly,but myocardial enzymes and troponin-Ⅰ decreased significantly.Conclusion Compared with drug therapy,ECMO improves left ventricular diastolic function,and may improve systolic function.ECMO cannot reduce myocardial infarct size,but may have positive effect on ischemic areas to avoid further injury.