舒张期电位在左后分支室性心动过速射频消融中的作用

Impact of diastolic potential on the radiofrequency ablation of left posterior fascicular ventricular tachycardia

目的:分析舒张期电位与左后分支室性心动过速(室速)的相互关系及其对射频消融成功率的影响,探讨左后分支室速有效的消融部位。方法:选择我院2008-04-2010-01收治的28例无器质性心脏病的左后分支室速患者,心电图呈右束支传导阻滞,下壁导联QRS波为负向,电轴左偏,静脉注射维拉帕米可终止室速,心房快速刺激及心室程控刺激均可诱发出心动过速。于窦性心律时在左室后间隔标测到提前的浦肯野电位(P电位),如消融后未出现舒张期电位则重新寻找靶点,直至该部位消融后出现舒张期电位。结果:28例患者于窦性心律时在靶点处消融后均出现舒张期电位,心房及心室刺激均未能诱发室速,且随访6个月后均无复发。结论:舒张期电位的出现提示左后分支室速折返环的阻断,如消融后出现该电位可明显提高手术成功率。

Objective：To analyze the relationship between diastolic potential and left posterior fascicular ventricular tachycardia（LPFVT）.To evaluate the impact of diastolic potential on radiofrequency ablation of LPFVT,and investigate the effective ablation site of LPFVT.Method：Twenty-eight patients with LPFVT underwent radiofrequency ablation between Apr 2008 and Jan 2010 were collected.Electrocardiogram of LPFVT manifested right bundle branch block in precordial leads and negative QRS in inferior leads with left-axis deviation,and LPFVT could be induced by rapid atrial stimulation or programmed ventricular stimulation,which could be terminated by intravenous administration of verapamil.The earliest Purkinje potential was mapped in posterior septal of left ventricular during sinus rhythm.If diastolic potential didn＇t appear after ablation,another target was searched until the appearance of diastolic potential.Result：Twenty-eight cases were found diastolic potentials in sinus rhythm after ablation,consequently LPFVT could not be precipitated by atrial and ventricular stimulation,which not recurred in the following 6 months of follow-up.Conclusion：The appearance of diastolic potentials after ablation indicates the interruption of circuit of LPFVT,which could be a marker of successful ablation.