小鼠心梗模型的建立与早期心电图评价

目的 构建并优化小鼠心肌梗死模型，联合使用冠脉结扎术后即刻和术后4 h的两次肢体导联心电图对心梗发生情况进行早期评价。方法 C57BL/6J雄性小鼠29只，异氟烷吸入麻醉后，经左侧第3/4肋间进入胸腔，结扎冠状动脉左前降支建立模型，施行术后即刻和术后4 h肢体导联心电图评价心梗发生情况。术后24 h打开胸腔观察梗死情况，留取心脏标本进行TTC染色确定梗死区域并计算梗死面积。结果 小鼠行冠状动脉结扎术，术中死亡率为6.8%(2/29)，术后早期(<4 h)死亡率为10.3%(3/29)，24 h存活率为82.8%(24/29)；术后24 h TTC染色明确梗死发生，则心梗模型建立，造模成功率为79.3%(23/29)，平均梗死区域大小（梗死心肌重量/全心室重量）为（28±6）%；成功建立模型的小鼠在术后4 h心电图可见明显ST-T改变，提示心梗已发生。结论 成功建立小鼠心肌梗死模型，且联合使用术后即刻和术后4 h两次心电图可以作为小鼠心肌梗死模型快速无创的评价方法。

Establishment of mouse myocardial infarction model and early electrocardio- gram assessment

Objective To establish and optimize a mouse myocardial infarction (MI) model, and to use twice limb lead ECGs immediately after coronary ligation and 4 h after surgery to evaluate the occurrence of myocardial infarction.Methods Twenty-nine male C57BL/6J mice were anesthetized with isoflurane. then a myocardial infarction model was established by ligating the left anterior descending (LAD) coronary artery through the third/fourth intercostal space of left anterior chest. Immediate and 4 h postoperative limb lead ECGs were performed. Twenty-four hours after surgery, the chest was opened and the occurrence of myocardial infarction was evaluated. The heart samples were taken for TTC staining to determine the infarct area and calculate the infarct area.Results During the mice underwent coronary artery ligation the intraoperative mortality was 6.8% (2/29), and the early postoperative (<4 h) mortality was 10.3% (3/29). The 24 h survival rate was 82.8% (24/29). 24 hours after TTC staining confirmed the occurrence of infarction, the myocardial infarction model was established. The success rate of the model was 79.3% (23/29), and the average infarct size (infarcted myocardial weight / whole ventricular weight) was (28 ±6)%; The mice successfully established by the model showed obvious ST-T changes in the ECG at 4 hours after surgery, suggesting that a myocardial infarction has occurred.Conclusions The mouse myocardial infarction model was successfully established. The combined use of ECG immediately after surgery and 4 h after surgery could be used as a rapid and non-invasive evaluation method for mouse myocardial infarction.