短暂性心肌缺血后再灌注心脏收缩功能随时间的变化研究  

Changes of Cardiac Systolic Function over Time after Transient Myocardial Ischemia and Reperfusion

作　　者：陈冬冬[1] 刘俭[1] 廖禹林[2] 陶宇[1] 伍巍兰[1] 袁野[1] 吴平生[1] 宾建平[1] 

机构地区：[1]南方医科大学南方医院心内科,广东省广州市510515 [2]南方医科大学病理生理教研室

出　　处：《中国全科医学》2011年第11期1215-1218,共4页Chinese General Practice

基　　金：国家"863"科技计划项目(2006AA02Z478)

摘　　要：目的应用速度向量成像(VVI)技术和心导管探讨不同时间短暂性心肌缺血后再灌注心脏局部和整体收缩功能随时间的变化规律。方法将20只wistar大鼠随机分为4组(假手术组和3个心肌缺血/再灌注组),通过调节阻断大鼠冠脉前降支时间制作不同缺血时间(5、10和15 min)的心肌缺血/再灌注(MI/R)模型,在冠脉阻断前、缺血结束时和再灌注(1～240 min)时取左室短轴乳头肌切面进行VVI分析,测定收缩期峰值应变(Ssys),并应用心导管测量相应时间的左室内收缩压(LVSP)和左室内压力上升最大速率(+dP/dt)。结果在缺血结束时3个MI/R组大鼠的LVSP和+dP/dt与冠脉阻断前比较明显减小(P<0.05),但在再灌注后所有MI/R组的LVSP和+dP/dt即可恢复。所有MI/R组大鼠在缺血结束时缺血区心肌的Ssys和冠脉阻断前比较,明显减小(P<0.05);在心肌再灌注1 min时,缺血5 min组大鼠缺血区心肌的Ssys迅速恢复,缺血10 min组的大鼠缺血区心肌的异常Ssys再灌注120min时恢复正常;而缺血15 min组的大鼠缺血区心肌的异常Ssys到再灌注240 min时能恢复正常。假手术组大鼠的LVSP、+dP/dt和Ssys在实验前后均无明显变化。结论 10～15 min的短暂性心肌缺血在再灌注后有较长时间的局部收缩功能异常,可作为心肌缺血的记忆指标用于临床诊断。Objective To study the changes of local and global cardiac systolic functions over time after transient myocardial ischemia and reperfusion.Methods Twenty Wistar rats were equally divided into one sham group and three myocardial ischemia-reperfusion（MI/R） groups.MI/R models were established by transient occlusion（5,10,and 15 min,respectively） of the proximal left anterior descending artery followed by reperfusion.Velocity vector imaging（VVI） was performed at baseline,upon the completion of occlusion,and at different time points after reperfusion（1 to 240 min）.Peak systolic strain（Ssys） was determined at short axis view of papillary muscle level.Left ventricular systolic pressure（LVSP） and the maximum rate of rise of left ventricular pressure（＋dp/dt） were also evaluated by cardiac catheter.Results Upon the completion of ischemia,LVSP and ＋dp/dt were significantly decreased in all MI/R groups（P0.05） and recovered to baseline levels immediately after reperfusion.During occlusion,Ssys of risk area was also significantly decreased in three MI/R groups（P0.05）.At 1 min of reperfusion,Ssys of risk area recovered to baseline immediately in the 5-min group,while decreased Ssys were not noted until 120 min in the 10 min group and 240 min in the 15 min group.In the sham group,LVSP/＋dp/dt and Ssys did not change significantly throughout the experiment.Conclusion Abnormal local cardiac systolic function persists 10～15 min after myocardial ischemia/reperfusion,and therefore it can be used as an indicator for detecting myocardial ischemic memory.

关 键 词：心肌缺血 心肌再灌注 速度向量成像 心脏收缩 

分 类 号：R542.22[医药卫生—心血管疾病]