经皮穿刺心外膜电-解剖标测及射频消融心肌梗死后室性心动过速的实验研究

目的探讨经心外膜途径在电-解剖标测系统指导下行射频消融治疗心肌梗死后室性心动过速的可行性和安全性。方法成年中华小型猪共7只,采用经皮穿刺的方法将球囊置于左前降支中下部,封堵150 min建立心肌梗死模型。3～5周后将心肌梗死模型猪,行电生理检查诱发室性心动过速。经胸穿刺进入心包腔,采用电-解剖标测系统在窦性心律下进行心外膜电压标测和线性消融。射频消融后再次行电生理检查,不能再诱发室性心动过速为消融成功。结果存活的心肌梗死模型的猪7只,3～5周后行电生理检查,共诱发出单形性室性心动过速共8种,7种表现为右束支阻滞图形,1种表现为左束支阻滞图形,室性心动过速(VT)周长平均在(338±66)ms。1只猪同时诱发心室颤动,电除颤转复窦性心律。7只猪心包穿刺均成功,完成心外膜电压标测,沿瘢痕区到二尖瓣环或正常心肌区逐点进行线性消融。射频消融后再次行电生理检查,6只猪不能再诱发室性心动过速。结论经胸穿刺进入心包腔行心外膜标测和消融治疗心肌梗死后室速的方法是安全可行的,心外膜标测消融心肌梗死后室速的方法可以作为心内膜消融的一种有效补充方法。

Nonsurgical transthoracic epicardial electroanatomie mapping and radiofrequency ablation of ventricular tachycardia after healed myocardial infarction

Objective To observe the feasibility and safety of the nonsurgical transthoracic epicardial electroanatomic mapping and radiofrequency ablation of ventricular tachycardia(VT) after healed myocardial infarction.Methods Seven ZhongHua small pigs underwent the following procedure to establish healed myocardial infarction model.The distal left anterior descending of left coronary artery was occluded by percutaneous angioplasty balloon for 150 minutes.VT was induced in electrophysiologic study after 3-5 weeks.Transthoracic pericardicentesis electroanatomic mapping and radiofrequency ablation were performed in the survived pigs.Results Eight kinds of VT were induced before ablation,seven of them were VT with right bundle branch block morphology and one of them was left bundle branch block morphology.The mean cycle length of VT was(338±66) ms.Ventricular fibrillation was induced in one pig simultaneously.The epicardial electroanatomic mapping was accomplished successfully under sinus rhythm in seven pigs.VT was not induced after ablation of the area from the scar tissue to mitral valve or normal tissue zone.Conclusion Nonsurgical transthoracic epicardial electroanatomic mapping and radiofrequency ablation are effective methods to eliminate VT after healed myocardial infarction.