碎裂电位指导下特发性流出道室性心律失常消融

Discrete potentials guided ablation for idiopathic outflow tract ventricular arrhythmias

目的 评价碎裂电位在指示特发性流出道室性心律失常消融靶点方面的意义.方法 2012年9月至2013年12月在天津医科大学第二医院心脏科行流出道室性早搏消融的患者共24例,其中17例特发性流出道室性早搏患者被纳入本研究,记录并分析标测和消融过程中心腔内电图.结果 全部17例患者标测过程中,均可在窦性心律下记录到尖锐、高频碎裂电位发生于局部心室电位之后或埋藏于局部心室电位之中,峰值振幅为（0.51±0.21）mV.室性早搏或室性心动过速发生时,该碎裂电位与局部心室电位的顺序关系发生自发性反转.心内高密度接触标测显示,该碎裂电位对应低电压区域.在记录到碎裂电位的区域内,窦性心律下局部心室电位低于毗邻的无碎裂电位区域[单极电压：（6.1±1.8）mV比（8.3 ±2.3）mV,P＜0.05;双极电压：（0.62 ±0.45） mV比（1.03±0.60） mV,P＜0.05].成功消融后,该碎裂电位仍能在12例患者的靶点处记录到.7例对照患者未见碎裂电位及低电压区.结论 碎裂电位及相关低电压区在特发性室性心律失常患者中很常见.碎裂电位指导的基质标测可作为供选择的流出道室性心律失常消融策略.

Objective Discrete potentials （DPs） have been recorded and targeted as the site of ablation of the outflow tract arrhythmias.The aim of the present study was to investigate the significance of DPs with respect to mapping and ablation for idiopathic outflow tract premature ventricular contractions （PVCs） or ventricular tachycardias （VTs）.Methods Seventeen out of 24 consecutive patients with idiopathic right or left ventricular outflow tract PVCs/VTs who underwent radiofrequency catheter ablation between September 2012 and December 2013 in our department were included.Intracardiac electrograms during the mapping and ablation were analyzed.Results During sinus rhythm,sharp high-frequency DPs that displayed double or multiple components were recorded following or buried in the local ventricular elec0trograms in all of the 17 patients,peak amplitude was （0.51 ± 0.21） mV.The same potential was recorded prior to the local ventricular potential of the PVCs/VTs.Spontaneous reversal of the relationship of the DPs to the local ventricular electrogram was noted during the arrhythmias.The DPs were related to a region of low voltage showed by intracardiac high-density contact mapping.At the sites with DPs,unipolar and bipolar ventricular voltage of sinus beats were lower compared with the adjacent regions without DPs （unipolar：（6.1 ± 1.8）mV vs.（8.3 ±2.3）mV,P 〈0.05;bipolar：（0.62 ±0.45）mY vs.（1.03 ±0.60） mV,P 〈 0.05）.The targeted DPs were still present in 12 patients after successful elimination of the ectopies.Discrete potentials were not present in seven controls.Conclusions Discrete potentials and related low-voltage regions were common in idiopathic outflow tract ventricular arrhythmias.Discrete potential-and substrate-guided ablation strategy could help to reduce the recurrence of idiopathic outflow tract arrhythmias.