摘要
目的用体视学定量法对比分析两种二尖瓣置换术(MVR)对心肌超微结构的影响,旨在为浅低温体外循环心脏不停跳心内直视手术对心肌保护效果作进一步客观的评价。方法将40例风湿性心脏病二尖瓣病变患者随机分为两组进行手术,20例在浅低温体外循环心脏不停跳下行MVR(不停跳组),20例在中低温冷血停搏液灌注心脏停跳下行MVR(停跳组)。两组均分别于体外循环前后切取少许心肌组织,用计算机图像分析系统对心肌超微结构的体视学定量进行对比分析。结果两组线粒体各参数在转流前差异无显著性(P均>0.05)。停跳组在转流中、后线粒体平均直径(Dmit)、平均截面积(Amit)较转流前增大,但体密度(Vmit)、面数密度(Namit)、比表面(δmit)较不停跳组减少,差异均有显著性(P<0.05或P<0.01);两组肌原纤维体密度(Vvmyo)在转流前、转流中变化不大,差异均无显著性(P均>0.05),而转流后停跳组肌原纤维Vvmyo、比表面(δmyo)均较不停跳组减少,差异有显著性(P<0.05和P<0.01)。结论浅低温体外循环心脏跳动中心内直视手术是一种较接近生理状态的心肌保护方法,能最大程度地减轻心肌缺血、缺氧损伤,避免再灌注损伤,最大程度地保持心肌细胞形态结构的完整性,从而获得较理想的心肌保护效果。
Objective To appraise objectively the myocardial protective effect of beating heart with mild hypothermia and cardiopulmonary bypass （CPB） with cardiac arrest by cold cardioplegia perfusion during open -heart operation for mitral valve replacement （MVR）. Methods Forty patients with rheumatic heart disease were randomly allocated to two groups： ①beating heart group： 20 cases of MVR with beating heart under mild hypothermia and CPB; ②heart arrest group： 20 cases of MVR with heart arrest by using cold blood cardioplegia （CBC） and CPB. Samples of myocardium were obtained at 3 times points during CPB, and myocardial ultrastructure was observed and analysed for both groups. Results There was no difference in ultrastructure of pre -operation specimens between two groups.-↑Dmit and -↑Amit were higher in arrested heart group than those in beating heart group during operation and after operation, but Vmit, Namit and δmit were significantly lower in cardiac arrest group than those in beating heart group （P〈0.05 or P〈0.01）. There were no significant differences of Vvmyo between preoperation stage and intraoperation stage （both P〉0.05） in both groups, while Vvmyo and δmyo of postoperation stage were significantly lower in heart arrest group than beating heart group （P〈0.05 and P〈0.01）. Conclusion Beating heart during open-heart surgery is a good method to protect the myocardium being close to physiological condition, and the protective effect may be attributed to alleviation of ischemia/reperfusion injury.
出处
《中国危重病急救医学》
CAS
CSCD
北大核心
2005年第9期533-536,共4页
Chinese Critical Care Medicine
基金
江苏省南京市医学重点科技发展项目(ZKX0404)
