左束支阻滞型特发性室性心动过速的心电图特征对射频消融成功的影响初探

对心电图呈左束支阻滞型的特发性室性心动过速 (简称室速 )的临床特点和心电图进行分析 ,以了解哪些因素可以预测此类患者从右室流出道行射频消融的成功率。对 2 6例特发性室速的患者进行电生理检查和射频消融手术 ,全部患者室速时的心电图呈左束支阻滞。结果 :2 6例中 ,2 2例于右室流出道进行了成功消融 ,成功和未成功消融的患者临床特征和电生理无明显区别 ,成功消融的患者中胸前V1 导联心电图呈rS型 (1 2例 )和QS型 (1 0例 ) ,而 4例未成功者 ,V1 导联均呈rS型 ,其中 2例经主动脉于左冠状窦消融成功。在成功与未成功消融患者中 ,V1 导联有无R波无明显区别 ,但V1 导联无R波预示室速可以从右室流出道成功消融 ,成功消融的室速患者胸前导联的平均移行区在V4导联 ,而未成功患者胸前导联的移行区在V3 或V2 导联。结论 :某些心电图呈左束支阻滞 ,且额面电轴正常或右偏的特发性室速患者不能成功从右室流出道消融 ,V1 导联有r波且移行区在V3 导联或之前者提示此类心电图特征的室速可能非起源于右室流出道 ,部分可能起源于左室流出道

Relation Between the Electrocardiagram Features of Idiopathic Ventricular Tachycardia With Left Bundle Branch Block Morphology and Outcomes of Radiofrequency Ablation From Right Ventricular Outflow Tract

The aim of the study was to evaluate the factors that can predict the outcomes of radiofrequency ablation from right ventricular outflow tract(RVOT) in patients with idiopathic ventricular tachycardia(VT) with QRS morphology of left bundle branch block(LBBB).Radiofrequency ablation from RVOT were performed in 26 patients.Among them,22 cases were ablated successfully ,2 of 4 failed patients were successful ablated subseqentialy from left coronary cusp.There was no signifinant difference on clinical characteristics and electrophysiology findings between two groups.The VTs with successful ablation from RVOT showed an rS or QS pattern in lead V 1 with median precordial transtional zones of ECG at V 4(range V 3-V 6),and all failed cases showed an rS pattern in lead V 1 with precordial transtional zones of ECG at V 2 or V 3. Conclusion:Some VTs with LBBB and inferior or normal axis can not be ablated from RVOT.The presence of an R wave in lead V 1 associated with a precordial transition zone at lead V 3 or V 2 suggests that the VTs may not arise from the RVOT,and may arise from Left ventricular outflow tract or other areas of heat.