Arrhythmia Unit, Hospital Universitari Vall d'Hebron, Barcelona, Spain.
Arrhythmia Unit, Hospital Universitari Vall d'Hebron, Barcelona, Spain.
Heart Rhythm. 2019 Jun;16(6):905-912. doi: 10.1016/j.hrthm.2018.12.015. Epub 2018 Dec 18.
Patients with syncope and bundle branch block (BBB) are at risk for atrioventricular block (AVB). Electrophysiological study (EPS) can help in identifying patients at higher risk for AVB, but the false-negative rate is remarkable. Few data on the predictors of the need for pacemaker implantation during follow-up have been reported.
The purpose of this study was to analyze the rate of patients who need pacemaker implantation after negative EPS and predictive factors.
A single-center prospective study of 159 consecutive patients (73.9 ± 12.1 years; male 64.9%) with syncope and BBB (January 2012-December 2016) and negative EPS was conducted. An implantable loop recorder was implanted.
After 27.9 ± 10.8 months of follow-up, 39 patients (24.8%) underwent pacemaker implantation because of bradyarrhythmia. In the univariate analysis, bifascicular (right BBB + left fascicular block) block, bifascicular block + long PR interval, conduction disturbance different from isolated right BBB, HV ≥60 ms, and HV ≥70 ms after class I drug challenge were predictors of pacemaker implantation. In the multivariate analysis, only bifascicular block (hazard ratio 2.5; 95% confidence interval 1.4-4.8; P = .04) and HV interval ≥60 ms (hazard ratio 3.5; 95% confidence interval 1.8-6.2; P <.001) were statistically significant. A risk score according to the multivariate model identified 3 levels of pacemaker implantation rate (13.5%, 32.7%, and 66.7%; P <.001). No death or severe trauma related to bradyarrhythmia occurred.
The strategy of an implantable loop recorder in patients with syncope and BBB is safe after negative EPS, but some patients might need pacemaker implantation during follow-up. A risk score based on HV ≥60 ms and bifascicular block can be useful in identifying patients at risk for advanced AVB after negative EPS.
晕厥伴束支传导阻滞（BBB）的患者存在发生房室传导阻滞（AVB）的风险。电生理研究（EPS）有助于识别发生 AVB 风险较高的患者，但假阴性率较高。关于随访期间需要起搏器植入的预测因素的报道较少。
本研究旨在分析 EPS 阴性患者需要起搏器植入的比例和预测因素。
对 2012 年 1 月至 2016 年 12 月期间因晕厥伴 BBB 而接受 EPS 阴性的 159 例连续患者（73.9 ± 12.1 岁；男性占 64.9%）进行了单中心前瞻性研究。植入了植入式循环记录仪。
在 27.9 ± 10.8 个月的随访期间，39 例（24.8%）患者因缓慢性心律失常而植入起搏器。在单因素分析中，双分支（右束支阻滞+左束支阻滞）阻滞、双分支阻滞+长 PR 间期、与孤立性右束支阻滞不同的传导障碍、HV≥60 ms 和 I 类药物试验后 HV≥70 ms 是起搏器植入的预测因素。在多因素分析中，只有双分支阻滞（风险比 2.5；95%置信区间 1.4-4.8；P=0.04）和 HV 间期≥60 ms（风险比 3.5；95%置信区间 1.8-6.2；P<0.001）有统计学意义。根据多变量模型制定的风险评分确定了 3 个起搏器植入率水平（13.5%、32.7%和 66.7%；P<0.001）。无与缓慢性心律失常相关的死亡或严重创伤。
在 EPS 阴性的晕厥伴 BBB 患者中，植入式循环记录仪策略是安全的，但部分患者在随访期间可能需要植入起搏器。基于 HV≥60 ms 和双分支阻滞的风险评分有助于识别 EPS 阴性后发生严重 AVB 的高危患者。
