Heart Rhythm. 2017 Aug;14(8):e255-e269. doi: 10.1016/j.hrthm.2017.03.006. Epub 2017 Mar 9.
To determine, using systematic review of the biomedical literature, whether pacing reduces risk of recurrent syncope and relevant clinical outcomes among adult patients with reflex-mediated syncope.
MEDLINE (through PubMed), EMBASE, and the Cochrane Central Register of Controlled Trials (through October 7, 2015) were searched for randomized trials and observational studies examining pacing and syncope, and the bibliographies of known systematic reviews were also examined. Studies were rejected for poor-quality study methods and for the lack of the population, intervention, comparator, or outcome(s) of interest.
Of 3,188 citations reviewed, 10 studies met the inclusion criteria for systematic review, including a total of 676 patients. These included 9 randomized trials and 1 observational study. Of the 10 studies, 4 addressed patients with carotid sinus hypersensitivity, and the remaining 6 addressed vasovagal syncope. Among the 6 open-label (unblinded) studies, we found that pacing was associated with a 70% reduction in recurrent syncope (relative risk [RR]: 0.30; 95% confidence interval [CI]: 0.15-0.60). When the 2 analyzable studies with double-blinded methodology were considered separately, there was no clear benefit (RR: 0.73; 95% CI: 0.25-2.1), but confidence intervals were wide. The strongest evidence was from the randomized, double-blinded ISSUE-3 (Third International Study on Syncope of Uncertain Etiology) trial, which demonstrated a benefit of pacing among patients with recurrent syncope and asystole documented by implantable loop recorder.
There are limited data with substantive evidence of outcome ascertainment bias, and only 2 studies with a double-blinded study design have been conducted. The evidence does not support the use of pacing for reflex-mediated syncope beyond patients with recurrent vasovagal syncope and asystole documented by implantable loop recorder.
通过对生物医学文献的系统评价，确定起搏是否降低反射性晕厥患者的晕厥复发风险和相关临床结局。
检索 MEDLINE（通过 PubMed）、EMBASE 和 Cochrane 对照试验中心注册库（截至 2015 年 10 月 7 日），以查找有关起搏和晕厥的随机试验和观察性研究，并查阅已知系统评价的参考文献。因研究方法质量差以及缺乏研究人群、干预措施、比较措施或感兴趣的结局而排除研究。
在审查的 3188 条引用文献中，有 10 项研究符合系统评价的纳入标准，共纳入 676 例患者。这 10 项研究包括 9 项随机试验和 1 项观察性研究。其中 4 项研究针对颈动脉窦过敏患者，其余 6 项研究针对血管迷走性晕厥患者。在 6 项开放性（未设盲）研究中，我们发现起搏可使晕厥复发率降低 70%（相对风险 [RR]：0.30；95%置信区间 [CI]：0.15-0.60）。当分别考虑 2 项采用双盲方法的可分析研究时，并无明确获益（RR：0.73；95% CI：0.25-2.1），但置信区间较宽。最强的证据来自随机、双盲的 ISSUE-3（不明原因晕厥的第三次国际研究）试验，该试验表明在有植入式环路记录器记录的反复晕厥和停搏的患者中，起搏具有获益。
虽然存在有限的、具有实质性结局评估偏倚证据的数据，但仅进行了 2 项双盲设计的研究。证据不支持起搏用于反射性晕厥，除了有植入式环路记录器记录的反复血管迷走性晕厥和停搏的患者之外。
