三尖瓣环下侧壁起源房性心动过速的射频消融治疗

目的报道三尖瓣环非间隔部位起源的房性心动过速(简称房速)体表心电图特点及射频消融治疗效果。方法 5例房速均被证实起源于三尖瓣环下侧壁部位并行射频消融治疗。影像学消融靶点位于三尖瓣环,局部电图可见A波和V波,且A∶V<2,V波的振幅>0.5mV。结果 5例房速均射频消融成功,部位位于三尖瓣环下侧壁,靶点局部A波激动时间领先体表心电图P波起点(48±16)ms,AV比值(0.5±0.4)。三尖瓣环下侧壁起源的房速P波特点:I、avL、aVR导联P波正向,Ⅱ、Ⅲ、aVF导联P波负向,V1~V6导联P波负向。结论三尖瓣环非间隔部位是右房房速的一个重要起源点,其体表心电图有明确特征。

Electrocardiographic Characteristics and Radiofrequency Catheter Ablation of Atrial Tachycardia Originating from the Nonseptal Region of the Tricuspid Annulus

Objectire To delineate the electrocardiographic features and results of radiofrequency catheter ablation （RFCA） of atrial tachycardia （AT） originating from the nonseptal region of tricuspid annulus （TA）. Methods The study included 5 patients with ATs originating from the nonseptal region of TA. The location of the AV annnli was confirmed by using the AV ratio of the local electrograms （A ： V〈2） and the amplitude of the ventricular electrograms （〉0.5mV） in addition to the anatomic findings under fluoroscopic guidance. Results All AT were successfully ablated by RFCA. The annular focus was localized to the inferolateral TA. The target atrial electrogram precedes the onset of P wave in surface electrocardiogram by （48±16）ms. The AV ratio of the local electrograms was （0.5±0.4）. In the inferolateral TA, the P wave morphology was positive in I, aVL, aVR, but was inverted in inferior and V1-V6 leads. Conclusion The nonseptal region of TA is an important site of right AT origin with characteristic P wave morphology.