中文摘要：

目的建立小鼠的较标准化的心肌梗死模型和利用心脏超声心动图进行无创心功能的评价。方法野生型雄性小鼠20只，在气管插管后由左侧第4肋间进胸，结扎冠状动脉左前降支从而建立心肌梗死模型。在模型建立前3天和模型建立后第2周使用超声心动图评价左室收缩末直径、舒张末直径和缩短分数。结果小鼠心肌梗死建立中急性死亡率20％（4／20），术后1周内死亡率40％（8／20）。经过超声评价，10只小鼠心肌梗死模型建立成功。小鼠心功能明显下降，缩短分数由术前50．23％±8．36％下降至25．41％±0．97％（t=16．18，P〈0．001）；心室明显扩大，左室舒张末直径由（0．32±0．03）cm扩大至（0．36±0．06）cm（t=-4．28，P=0．002），收缩末直径由（0．15±0．03）cm扩大至（0．19±0．05）cm（t=-8．05，P〈0．001）。病理学检查见明显瘢痕形成，模型的总体成功率为50％（10／20）。结论可以通过常规外科技术建立小鼠的心肌梗死模型，然后利用超声心动图无创评价心功能，筛选合格的动物模型。

英文摘要：

Objective To establish a standardized mouse myocardial infarction model, and non-invasively evaluate its cardiac function by using the echocardiography. Methods A total of 20 wild male mice were enrolled into this study. The left anterior descending coronary was ligated through the left fourth intercostal space after intubation. The echocardiographic assessment of myocardial infarction and heart function was performed 3 days preoperatively and 2 weeks postoperatively. The shortening fraction （FS） , end systolic dimension （ESD） , and end diastolic dimension （EDD） was recorded and analyzed. Results The acute and one-week mortality rates were 20% （ 4/20 ） and 40% （ 8/20 ） , respectively. The echocardiography showed that the myocardial infarction model was successfully established in 10 mice. The heart function of the mice was markedly impaired. The FS significantly decreased from （50.23 ± 8.36） % to （25.41 ± 0.97） % （ t = 16. 18, P 〈 0. 001 ） , while EED and ESD were increased significantly [（0.32±0.03） cm and （0.15 ±0.03） cm vs. （0.36 ±0.06） cm and （0.19 ±0.05） cm; t = -4.28, P=0.002, and t = - 8.05, P 〈 0.001, respectively ]. Pathological examination confirmed scar formation. Totally, the success rate of establishment of the mice model was 50% （10/20）. Conclusions It is feasible to establish a myocardial infarction model in mouse by using conventional surgical and anesthesia techniques. The echocardiography offers a noninvasive approach to assess the cardiac function of the mice and to choose suitable animals for further studies.