急性缺血再灌注左室局部功能与心肌细胞凋亡的相关性研究

目的探讨应变率成像评价急性缺血再灌注后左心室功能与肌细胞凋亡的相关性及其应用价值。 方法健康杂种犬30只，分对照组（10只），缺血组（10只），再灌注组（10只）。缺血组于第一对角支1cm以下套扎左冠状动脉前降支30min，再灌注组套扎30min后再灌注120min，对照组游离左冠状动脉前降支不结扎。超声心动图左室收缩期应变率测量左室局部收缩功能，Simpson’s法测左室射血分数，原位末端脱氧核苷酸转移酶标记技术（TUNEL）法检测缺血区心肌细胞凋亡数。 结果收缩期应变率与射血分数及心肌细胞凋亡数相关性良好。峰值收缩期应变率在三组之间均有显著性差异（P值均＜0.05），射血分数在三组之间无显著性差异（P＞0．05），心肌阳性凋亡细胞数仅在再灌注组与对照组之间有显著性差异（P＜0．05）。 结论应变率成像为临床提供了一个敏感、简便的评价早期心肌局部收缩功能的指标，局部心功能与心肌细胞凋亡相关。

Correlation Between Apoptosis and Left Ventricular Segmental Function in Acute Myocardial Ischemia Reperfusion:Experimental Study

Objective To assess the ability of strain rate imaging(SRI) for evaluating left ventricular systolic function and to investigate the relationship between apoptosis and left ventricular segmental function following acute ischemia reperfusion in dogs.Methods Thirty-one dogs were divided into ischemia(10),reperfusion(11)and the control(10) groups.Left anterior descending coronary arteries(LAD) were occluded 30 min in ischemia groups and dogs in reperfusion group were reperfused 120 min after LAD 30 min ligation.Dogs without LAD ligation were used as the control group.The left ventricular segmental function was detected by echocardiography using strain rate analysis software.Left ventricular ejection fraction(LVEF) was developed from Simpson formula.Numbers of apoptosis in the left myocardial dysfunction area were detected using terminal deoxynucleotidyl transferase mediated biotinylated deoxyuridine triphosphate nick end labeling(TUNEL).Results Peak systolic strain rate(SR) of the LV wall correlated with LVEF and with the number of myocardial cell apoptosis.SR was significantly descended in ischemia and reperfusion groups compared with the control group(P<0.05).There was no significant difference in LVEF between the three groups(P>0.05).The numbers of apoptosis were significantly increased in the reperfusion group(P<0.05).Conclusions SRI may provide a sensitive,simple and reliable tool to assess LV segmental function which are related to myocardial cell apotosis.