CO2对犬缺血心肌侧支循环形成的影响及对心功能的保护作用

目的：观察经冠状动脉注入缺血心肌内CO2对犬缺血心肌侧支循环形成的影响反对心功能的保护作用。方法：采用健康杂种犬，建立犬急性心肌缺血模型。将模型犬分成两组，实验组10只，每日注射95％的CO2（2ml／kg）；对照组9只，每日只注射与实验组等量的肝素生理盐水，共14d；另选5只为空白对照组。两周后行冠状动脉造影、超声心动图、病理学、免疫组化染色检查．评价各组心功能及侧支血管形成状况。结果：实验组较对照组心脏缺血部位微血管明显增多，侧支循环形成，心功能改善。结论：CO2能加速扩张冠状动脉侧支血管，加速缺血区冠状动脉侧史循环的建立，增加心肌缺血区微血管的密度，改善缺血区的血液供应，并有效地保护心功能。

Effects of CO2 on the development of coronary collateral circulation within ischemic myocardium and the protection of cardiac function

Objective: To observe the effect of CO2 on the development of coronary collateral circulation and the protection of heart function in ischemic myocardium. Methods: Canine models of acute myocardial ischemia were established with healthy mongral canine.The canines models were randomly allocated to be injected 95% CO2 (2 ml/kg) (experimental group, n=10) or equivalent volume of heparin-saline (control group, n=9). And 5 normal canines were selected as blank control. After two weeks, CAG, TDE, pathologic and immunohistochemical examinations were performed on them to observe the coronary collateral circulation and the heart function of each group. Results: Examinations showed better collateral circulation in experimental group, and the microvascular vessels significantly increased in the region of ischemia compared with the control group.Myocardial function was also better in experimental group than in the control group. Conclusions: CO2 can dilate the coronary collateral vessels, accelerate the establishment of the coronary collateral circulation, increase the density of microvascular in the ischemic myocardium, promote the blood supply to ischemic region, and protect the cardiac function effectually.