经冠状静脉系统导管射频消融心外膜室性心律失常

Radiofrequency catheter ablation of ventricular arrhythmias originating from the epicardium via coronary vein system

目的探讨冠状静脉系统(CVS)心外膜起源室性早搏(PVCs)/室性心动过速(VT)的心电图特征和标测消融的有效性及安全性。方法 12例无器质性心脏病患者,男10例,女2例,年龄49.08±15.26岁。体表12导联心电图(ECG)、动态心电图示频发PVCs或短阵VT。12例术中均先行心内膜标测,均未标测到理想消融靶点,考虑PVCs/VT源自心外膜,置入冠状静脉窦(CS)电极至心大静脉(GCV)、前室间隔静脉(AIV)。确定PVCs/VT起源于CVS后,应用盐水灌注消融导管,以15～30 W放电(温控43℃、盐水速度17～30 ml/min)。分析体表ECG特征。结果 10例即刻消融成功,消融靶点分别位于GCV(7例)、AIV(2例)、后侧支静脉(PLV)(1例),局部V波较体表心电图QRS波提早28.67±5.35 ms,消融部位阻抗212.8±45.2Ω;2例因消融导管无法到达AIV中段靶点,消融失败;无标测与消融并发症。PVCs/VT的QRS波时限为148.33±18.09 ms,起始部见"delta"波4例,最大偏差指数(MDI)0.67±0.27。PLV消融成功病例Ⅰ导联QRS波呈R型,另外9例PVCs/VT时的Ⅰ导联QRS波以负向波为主,其中5例GCV消融成功患者的Ⅰ导联QRS波起始部见q波(QWLⅠ)。GCV消融成功的PVCs/VT心电图呈右束支传导阻滞图形,胸前导联R波移行较早,移行于V1导联;AIV消融成功PVCs/VT心电图呈左束支传导阻滞图形,胸前导联R波移行于V3导联。随访1～10个月,1例PVCs 24 h 3 982个,余病例未见复发,成功率75%。结论QWLⅠ、MDI≥0.6是GCV起源的PVCs/VT重要诊断标准之一;约75%CVS起源的心外膜PVCs/VT可以经CVS安全、有效地进行标测和消融。

Objective To determine the safety and efficacy of radiofrequency catheter ablation （RFCA） of frequent premature ventricular contractions （PVCs） or ventricular tachycardia （VT） originating from the epicardium via coronary vein system（CVS）. Methods Twelve patients （10 men; age 49.08＋ 15.26 years） were found to have an epicardial site of origin who were diagnosed as PVCs or VT by electrocardiogram or Holtor. Radiofrequency application could not abolish PVCs/VT during endocardial mapping and ablation. Then, the PVCs or VT originated from epicardium were considerated, so multiple electrode catheter was introduced into great cardiac vein （GCV） or anterior interventricular vein （AIV）. After CVS epicardial orign for PVCs/VT had been determined by activation mapping and pace mapping, radiofrequency energy was delivered with the irrigated-tip catheter at a power of 15 to 30 W and a flow rate of 17 to 30 ml/min. Finally, the characteristics of electrocardiogram and results of ablation were analyzed. Results Ten of 12 patients underwent successful ablation within the CVS. In the 10 patients, the site of origin （SOO） of the ventricular arrhythmias was identified from within the GCV （ n = 7）, the AIV （ n = 2） or the posterior lateral vein （PLV） （n= 1 ）. The mean earliest activation preceding the onset of the QRS complex was 28.67 ± 5. 35 ms, and the mean impedance was 212.8±45.2 12. In the 2 patients with unsuccessful ablation, failure was be cause the ablation catheter could not be advanced to the SOO within the AIV. No complications occurred. QRS duration of PVCs/VT was 148.33 ± 18.09 ms, pseudo-deha wave was present in 4 patients. Maximum deflection index was 0.67 ± 0.27. One VT SOO within the PLV QRS complex positive in lead I , and QRS complex predominantly negative in lead I in all other successful patients. A q wave in lead Ⅰ （ QWL I） were seen in 5 patients with PVCs/VT were successful eliminated in the GCV. SOO within the GCV precordial R-wave transition in lead V1, exhibited a right bundle branch block QRS morphology; SOO within the AIV precordial R-wave transition in V3 , exhibited a left bundle branch block QRS morphology. During a follow-up period of 1 to 10 months, 1 PVCs recurred （total number of PVCs： 3982 beats during 24 h）, success rate was 75%. Conclusion The presence of a q wave in lead I and MDI ≥0.6 maybe an important morphology criteria for ventrieular arrhythmias originating from the GCV. The SOO of epicardial arrhythmias can be ablated from within the CVS in approximately 75% of patients.