中文摘要：

目的本文旨在探索判断右心室流出道室性早搏（室早）起源的新流程，以便快速、准确地找到消融靶点。方法采用非接触三维标测系统对右心室流出道室早进行标测与导管消融，并分析右心室流出道室早体表心电图特征。根据三维标测与导管消融结果，并结合先前报道的室早起源判断流程，设计新的判断室早起源流程。结果标测与消融结果显示21例患者室早起源于右心室流出道间隔部，其中5例起源于前间隔，4例起源于中间隔，12例起源于后间隔；17例患者室早起源于右心室流出道游离壁，其中5例起源于前游离壁，2例起源于中游离壁，10例起源于后游离壁；1例患者室早起源于希氏束附近。判断室早起源新流程的总阳性预测值（77．3％）较Ito等报道的73．3％、Joshi等报道的73．3％、Dixit等报道的53．8％显著提高（P〈0．05）。新流程在判断室早具体起源部位较Ito等、Joshi等与Dixit等报道的室早起源部位判断流程有较大的优势，其敏感性、特异性与阳性预测值分别为78．1％，88．9％与84．2％，Joshi等报道的流程分别为32．9％，65．8％与48．1％，Dixit等报道的流程分别为50．7％，63．9％和55．2％（P均〈0．05）。结论非接触三维标测系统指导右心室流出道室早消融成功率高，判断室早起源新流程的敏感性、特异性与阳性预测值较先前报道的高，有良好的临床应用价值。

英文摘要：

Objective In this study, we explored a new electrocardiographic algorithm for localizing idiopathic right ventricular outflow tract （RVOT）premature ventricular contraction （PVC）. Methods A total of 39 patients [ 23 female, mean age （41.8 ± 13.1 ） years] with RVOT-PVC enrolled in this study. Ablation was performed under the guidance of 3D non-contact mapping, and a newly proposed ECG algorithm. Results As guided by 3D mapping, the successful ablation was achieved at sites of RVOT septum （ n = 21 ）, RVOT free wall （ n = 17 ） and His region （ n = 1 ）. Among those PVCs originated from the RVOT septum, five were from the anterior wall, four were from the mid region and 12 were from the posterior wall. For those PVCs originated from RVOT free wall, five from the anterior wall, two from the mid region and 10 from posterior wall. The overall positive prediction value to identify a successful ablation site of this newly proposed ECG algorithm was 77. 3% and higher than the 73.3% by Ito et al; 73.3% by Joshi et al, and 53.8% by Dixit et al, respectively （ P 〈 0. 05 ）. Furthermore, the sensitivity, specificity, and positive prediction value to predict a more specific site within the 7 different regions （anterior, middle and posterior septal sites; anterior, middle and posterior free wall sites and His region） was 78. 1% , 88.9% and 84. 2% , respectively; and were significantly higher than those proposed by Joshi et al （32. 9%, 65.8% and 48.1%, respectively） and by Dixit et al （50. 7%, 63.9% and 55.2%, respectively all P 〈 0.05 ）. Conclusion Based on detail 3D mapping of successful ablation sites, a new proposed ECG algorithm was developed to improve the sensitivity, specificity and positive prediction value in identification of targeted ablation sites for RVOT-PVC.