结扎血管法制作犬急性心肌梗死模型的优势

Advantages of establishment of acute myocardial infarction model by ligation of coronary artery in dogs

目的探讨结扎冠状动脉分支制作急性心肌梗死动物模型的优势。方法将6只杂种犬经开胸手术并结扎左前降支制成心肌梗死模型,结扎血管后利用心电监护仪监测其心电图动态变化,并于结扎冠状动脉前、结扎后1h进行多层螺旋CT增强扫描。在增强图像上,观察心肌梗死的病变部位及形态,并测量其CT值。结果结扎左前降支血管后确切阻断左室前壁的血供,心电监护显示结扎后2min开始出现ST段抬高。结扎冠状动脉前6只犬心肌增强扫描均呈均匀强化,结扎后1h左心室前壁或心尖区有明显的低密度缺血区形成,结扎后1h图像上正常心肌与梗死心肌的CT值经统计学分析差异具有统计学意义(P<0.01)。结论通过结扎冠状动脉分支法制作心肌梗死模型方法可靠,操作简单,可作为心肌梗死实验研究的基础。

Objective To explore the advantage of establishment of acute myocardial infarction by ligation of coronary artery in dogs.Methods The left anterior descending branches of 6 hybrid canines were ligated to establish acute myocardial infarction model.The electrocardiogramic monitor recorded the changes of electrocardiogram after ligation of left anterior descending branch（LAD）.The enhanced CT scanning was performed one hour after ligation of LAD.Themorphologicalchangesandsites of ischemic myocardium were observed on enhanced CT images,and the CT value of normal myocardium and that of infarction area were measured.Results Ligation of LAD could obstruct blood flow of LAD accurately.ST-T segment elevated at two minutes after obstructing blood flow of LAD.For 6 hybrids,normal myocardium presented homogenized enhancement before ligating of LAD and ischemic areas at anterior wall or apex showed low density at one hour after LAD ligated.Statistically significant differences of the CT values between normal and infarction myocardium at one hour after ligation were found（P0.01）.Conclusion Ligation of LAD is a reliable and easily-operated method of establishing acute myocardial infarction model.It can provide a research basis for cardiac infarction.