右心室间隔部希氏束附近室性期前收缩心电图与射频消融

目的 报道右心室流入道间隔部希氏束附近起源室性期前收缩体表心电图特征及射频消融效果。方法 无器质性心脏病频发性室性期前收缩5例,分析其12导联体表心电图室性期前收缩特点;病人接受心内电生理检查,于右心室流入道行激动与起搏标测,以心室激动较体表QRS波提早、消融导管远端起搏图形与体表心电图室性期前收缩相似部位为消融靶点。结果 室性期前收缩QRS波形态：5例病人Ⅰ导联和Ⅱ导联QRS波均呈R型,Ⅲ导联、aVF导联以低振幅波为主,V1导联均呈QS型,胸导联较早转变成qR或R型（发生于V2或V3）,V5、V6均呈高R型;室性期前收缩QRS波时限为110～120ms。5例病人分别于前间隔（2例）、中间隔（1例）、后间隔（2例）标测到消融靶点,放电后前间隔部、后间隔部病人室性期前收缩均消失,中间隔病人消融失败。无房室传导阻滞并发症。随访8～30个月,成功病例未应用抗心律失常药物,无室性期前收缩发作。结论 右心室流入道间隔部希氏束附近起源室性期前收缩体表心电图具有明显的特征,认识这些特征有助于导管标测与射频消融,消融此部位室性期前收缩安全、有效。

Electricardiographic characteristics of ventricular premature contractions originating from right ventricular septum near the His-bundle and radiofrequency catheter ablation

Objectives To assess the surface electrocardiography （ECG） characteristics and the effects of radiofrequency catheter ablation （RFCA） on ventricular premature contractions （VPCs） originating from right ventricular inflow tract （RVIT） septum near the His-bundle. Methods 12 lead surface ECG analysis and electrophysiologic studies were performed in five normal heart patients with VPCs from RVIT septum. The ventricular activations （V waves） mapping and pacing mapping were used to locate the ablation targets where V waves preceded the onset of the VPCs and pacing produced a nearly identical ECG to surface VPCs. Results The surface ECG analysis revealed monophasic R wave on leads Ⅰ and Ⅱ , low R waves on leads m and aVF, QS pattern on lead V1, tall R wave on V5 and V6 in all five patients. Precordial R wave transition occurred on lead V2, V3. QRS duration of VPCs was 110-120 ms. VPCs originating from anterioseptum （n = 2） and posterioseptum （n= 2）were successfully abolished, but VPC from middle septum （n = 1） was unsuccessfully ablated. No complication occurred. No VPCs recurred during an 8-30 month follow-up without any antiarrythmia drugs. Conclusions The distinctive ECG characteristics of VPCs originating from RVIT septum near the Hisbundle are helpful for catheter mapping and ablation. These VPCs can be ablated successfully and safely.