胸腔镜下建立小型猪慢性心肌缺血模型

Create a standard mini-swine model of chronic ischemic myocardium by thoracoscopes

目的探讨应用胸腔镜技术建立小型猪慢性心肌缺血模型的效果及可行性。方法23只中国实验小型猪，雄性，体重20～30kg，平均（29．3±4．3）kg，年龄8-11个月，平均（9．3±1．8）个月。在完全胸腔镜下将Ameroid环置于回旋支主干，术前及术后6周分别进行冠状动脉造影及超声心动图检查。结果23只猪中20只顺利完成手术，手术时间25～125min，平均（46±9）min。术中出血量30～60ml，平均（55±12）ml。术后6周内因肺部感染、二次造影时心律失常及麻醉意外死亡3只。术后6周行冠状动脉造影显示，7只动物回旋支完全闭塞，13只狭窄大于85％。超声心动图心肌收缩及舒张功能明显下降，术前射血分数（65．0±6．3）％，短轴缩短率（36．2±4．3）％；术后6周射血分数（41．0±9．3）％，短轴缩短率（34．2±2．3）％，均低于术前水平（P〈0．05）。结论应用胸腔镜技术放置Ameroid环可以有效建立小型猪慢性心肌缺血模型。

Objective To create a standard mini-swine model of chronic ischemic myocardium by endoscopy for the research of gene transfer and stem cell. Methods Twenty-three male China experimental mini-swines were used, aged from 8 to 11 months with a mean of （9. 3 ±1.8） months and weighed from 20 to 30 kg with a mean of （29.3 ±4. 3） kg. The myocardial ischemia was established by gradual occlusion of the left circumflex coronary artery （LCX） with an Ameroid constrictor. The Ameroid constrictor was implanted around LCX by endoscopy. Selective coronary angiography, electrocardiogram and Echo-Doppler study were performed perioperatively to evaluate the degree of stenosis. Results Chronic ischemic myocardial models were successfully generated in 20 of 23 swine by full-endoscopy. Ameroid constrictors were placed at the LCX accurately. Three swine died of anesthetic accident, cardiac arrhythmia at secondary coronary angiography, and pulmonary infection within 6 weeks after operation respectively. Operation time was 25 to 65 min with a mean of （46 ±9） min. The blood loss was 30 to 60 ml with a mean of （55 ±12） ml. Six weeks later, coronary angiography revealed the total occlusion and partial stenosis （ 〉 85% ） of the LCX occurred in 7 and 13 swine respectively. Cardiac systolic and diastolic dysfunction were found in all swine. The ejection fraction value was （65.0± 6. 3）% before operation and （41.0 ±9. 3 ）% after operation （ P = 0. 008 ）. The fractional shortening value was （ 36. 2 ± 4.3 ） % before operation and （ 34.2 ± 2.3 ） % after operation （P =0. 027 ）. Conclusion The endoscopic surgery is a less invasive way to create a standard mini-swine model of chronic ischemic myocardium with effective results.