Wei Huiqiang, Tang Jiaojiao, Chen Dongli, Zhang Qianhuan, Liang Yuanhong, Liu Lie, Wu Shulin, Lin Chunying, Yang Zhiming, Chai Chanjuan
State Key Laboratory of Cardiovascular Disease, Arrhythmia Center, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
Department of Cardiology, The Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, China.
Clin Cardiol. 2018 Mar;41(3):354-359. doi: 10.1002/clc.22873. Epub 2018 Mar 25.
Electrocardiographic (ECG) characteristics of true right ventricular outflow tract (RVOT) septal pacing have not been clearly demonstrated.
We hypothesized that ECG parameters would help operators differentiate true RVOT septum from non-septal septum.
We analyzed 151 patients who underwent pacemaker implantation with a ventricular lead in the RVOT. Transthoracic echocardiographic (TTE) determination of pacing sites was applied in all patients after implantation. A 12-lead ECG was recorded during forced ventricular pacing.
According to TTE orientation, pacing at the RVOT septum was achieved in 94 patients (62.3%). Compared with nonseptal pacing, septal pacing had significantly shorter QRS duration (139.2 ± 18.5 ms vs 155.5 ± 14.7 ms; P < 0.001). More frequent negative or isoelectric QRS vector in lead I (76% vs 32%; P < 0.001), lead II/III R-wave amplitude ratio < 1 (52% vs 25%; P = 0.001), and aVR/aVL QS-wave amplitude ratio < 1 (59% vs 32%; P = 0.001) were observed in septal pacing. Transitional zone (TZ) score (3.8 ± 0.96 vs 4.2 ± 0.90; P = 0.004) and TZ index (0.3 ± 0.5 vs 0.6 ± 0.7; P = 0.008) were significantly lower in septal pacing than in nonseptal pacing, respectively. In multivariate analysis, paced QRS duration and negative or isoelectric QRS vector in lead I independently predicted RVOT septal pacing (P < 0.001). At ROC curve analysis, paced QRS duration ≤145 ms identified RVOT septal pacing with 85.1% sensitivity and 78.9% specificity.
This study reveals the heterogeneity of lead placement within the RVOT. Narrower paced QRS duration and negative or isoelectric QRS vector in lead I independently predict RVOT septal pacing.
真正的右心室流出道（RVOT）间隔起搏的心电图（ECG）特征尚未得到明确证实。
我们假设心电图参数将有助于操作人员区分真正的RVOT间隔与非间隔部位。
我们分析了151例在RVOT植入心室导联进行起搏器植入的患者。植入后对所有患者应用经胸超声心动图（TTE）确定起搏部位。在心室强制起搏期间记录12导联心电图。
根据TTE定位，94例患者（62.3%）实现了RVOT间隔起搏。与非间隔起搏相比，间隔起搏的QRS时限明显更短（139.2±18.5毫秒对155.5±14.7毫秒；P<0.001）。在间隔起搏中观察到I导联中负向或等电位QRS向量更频繁（76%对32%；P<0.001），II/III导联R波振幅比<1（52%对25%；P=0.001），以及aVR/aVL导联QS波振幅比<1（59%对32%；P=0.001）。间隔起搏的过渡区（TZ）评分（3.8±0.96对4.2±0.90；P=0.004）和TZ指数（0.3±0.5对0.6±0.7；P=0.008）分别显著低于非间隔起搏。在多变量分析中，起搏QRS时限和I导联中的负向或等电位QRS向量独立预测RVOT间隔起搏（P<0.001）。在ROC曲线分析中，起搏QRS时限≤145毫秒识别RVOT间隔起搏的灵敏度为85.1%，特异度为78.9%。
本研究揭示了RVOT内导联放置的异质性。更窄的起搏QRS时限和I导联中的负向或等电位QRS向量独立预测RVOT间隔起搏。
