Libin Cardiovascular Institute, University of Calgary, Calgary, Alberta, Canada.
Libin Cardiovascular Institute, University of Calgary, Calgary, Alberta, Canada.
Heart Rhythm. 2021 Aug;18(8):1310-1317. doi: 10.1016/j.hrthm.2021.04.010. Epub 2021 Apr 20.
Syncope may be caused by intermittent complete heart block in patients with bundle branch block. Electrophysiology studies (EPS) testing for infra-Hisian heart block are recommended by the European Society of Cardiology syncope guidelines on the basis of decades-old estimates of their negative predictive values (NPVs) for complete heart block.
The aim of this study was to determine the NPV of EPS for complete heart block in patients with syncope and bundle branch block.
We searched MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and CINAHL without language restriction from database inception to October 2019 for Medical Subject Headings terms and keywords related to "syncope," "heart block," and "programmed electrical stimulation." A random effects meta-analysis was conducted with a primary outcome of the proportion of patients with a negative EPS who later presented with complete heart block, diagnosed with surface electrocardiographic (ECG) recordings vs continuous implantable cardiac monitor (ICM).
Ten reports contained 12 cohorts with 639 patients who met the inclusion criteria. The mean age was 69 ± 7 years; 35% ± 10% were women; and 85% of patients had bifascicular block. Seven cohorts recorded clinical outcomes with external ECG recordings, and 5 cohorts featured ICMs. The mean prespecified His-to-ventricle interval criterion was ≥70 ms. In studies featuring surface ECG recordings, there were 7% (95% confidence interval 7%-17%) patients who developed complete heart block compared with 29% (95% confidence interval 24%-35%) in the studies featuring ICM (P = .0001).
The NPV of EPS in patients with syncope and bundle branch block is 0.71, sufficiently low to question its use.
束支传导阻滞患者可能会出现间歇性完全性心脏阻滞导致晕厥。根据欧洲心脏病学会晕厥指南，对于希氏束以下心脏阻滞的电生理研究（EPS）测试，基于几十年前对其完全性心脏阻滞的阴性预测值（NPV）的估计，建议进行 EPS 测试。
本研究旨在确定晕厥伴束支传导阻滞患者 EPS 对完全性心脏阻滞的 NPV。
我们在 MEDLINE、EMBASE、Cochrane 对照试验中心注册库和 CINAHL 中进行了无语言限制的检索，检索时间从数据库建立到 2019 年 10 月，使用与“晕厥”、“心脏阻滞”和“程控电刺激”相关的医学主题词和关键词。主要结局是阴性 EPS 患者中随后出现完全性心脏阻滞的比例，采用随机效应荟萃分析进行分析，诊断方法为体表心电图（ECG）记录与连续植入式心脏监测仪（ICM）比较。
10 份报告包含 12 个队列，共 639 名符合纳入标准的患者。平均年龄为 69 ± 7 岁；35%±10%为女性；85%的患者存在双束支阻滞。7 个队列记录了外部 ECG 记录的临床结局，5 个队列采用了 ICM。预设的希氏束至心室间期标准为≥70 ms。在采用体表心电图记录的研究中，有 7%（95%置信区间 7%-17%）的患者发生完全性心脏阻滞，而在采用 ICM 的研究中则有 29%（95%置信区间 24%-35%）（P =.0001）。
晕厥伴束支传导阻滞患者 EPS 的 NPV 为 0.71，足够低，足以质疑其应用。
