特发性右室流出道室性心律失常消融靶点的电生理特征

摘要

目的：分析特发性右室流出道（RVOT）室性心律失常消融靶点特点，探讨其可能的机制。方法连续选取2013年1月至2014年12月行导管射频消融的 RVOT 起源室性心律失常（PVCs/ VT）患者38例，借助三维标测系统于 PVCs/ VT 时建立右室流出道三维构图，分析有效消融靶点的电生理特点。结果所有心律失常患者进行三维激动/电压标测显示，最早心室激动点/消融靶点均位于 RVOT 肺动脉瓣附近的电压移行区上（0.5~1.5 mV），即电压移行区与正常电压区的交界处；其中有4例造影及三维图像与 CT 融合证实于肺动脉瓣上标测消融成功，并在肺动脉瓣上可以记录到大于1.5 mV 的电压电位（心肌组织）。结论电压移行区很可能是成功消融特发性 RVOT 室性心律失常的有效靶点区域；部分于肺动脉瓣上成功消融的室性心律失常，可能与心肌束延伸有关。%Objective To analyze the electrophysiological characteristics of successful radiofrequency ablation sites of idiopathic right ven-tricular outflow tract(RVOT)arrhythmias,and investigate the mechanism of idiopathic RVOT arrhythmias. Methods 38 consecutive patients with idiopathic RVOT arrhythmias(PVCs:premature ventricular contractions,VT:nonsustained ventricular tachycardia)were studied. Three -dimensional mapping was performed during PVCs/ VT. The characteristics of successful ablation site were examined. Results All patients under-went activation mapping and a bipolar voltage map was constructed simultaneously. The optimal ablation sites were at transitional - voltage zone (0. 5 - 1. 5 mV)near the pulmonic valve. Four RVOT arrhythmia foci were localized beyond the valve in the pulmonary artery,and bipolar voltage≥1. 5 mV(as surrogate for myocardial tissue)could be recorded above the pulmonary valve. Conclusion Transitional - voltage zone may be the effective ablation site in idiopathic RVOT arrhythmias. Myocardial extension into the pulmonary artery may serve as origins of supravalvular RVOT arrhythmias.