Aims. In the guidelines for cardiac resynchronization therapy (CRT), there is a gap between the Japanese Circulation Society (JCS) criteria, which specify a QRS duration of ≥120 ms, and other countries, with a QRS ≥ 130 ms. The efficacy of CRT remains controversial in patients with a narrow QRS <130 ms. The aims of this study are to evaluate the response to CRT in patients with a narrow QRS and to identify predictors of mortality. Methods. We retrospectively studied 212 patients who received CRT. They were divided into narrow QRS (<130 ms) and wide QRS (≥130 ms) groups. We compared CRT response rates and investigated whether age, gender, baseline New York Heart Association (NYHA) class, ischemic etiology, atrial fibrillation, and ventricular arrhythmias are associated with response and also predictive of mortality. Results. The CRT response rate was not significantly different between the wide QRS group and the narrow QRS group (74.6% versus 77.2%,  = 0.6876), and the response rate in the narrow QRS group was as good as that reported worldwide. NYHA class IV was shown to be a predictor of mortality (HR 9.38, 95% CI 5.35–16.3,  < 0.0001). Conclusions. The present study demonstrated that patients with a narrow QRS complex responded well to CRT. Even with QRS <130 ms, CRT should be tried if no other effective treatment is available.

中文翻译：

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窄QRS复合体患者心脏再同步治疗的疗效。

目的。在心脏再同步治疗（CRT）指南中，日本循环协会（JCS）标准（QRS持续时间≥120ms）与其他国家（QRS≥130 ms）之间存在差距。在狭窄QRS <130 ms的患者中，CRT的疗效仍存在争议。这项研究的目的是评估狭窄QRS患者对CRT的反应，并确定死亡率的预测因子。方法。我们回顾性研究了212例接受CRT的患者。他们分为窄QRS（<130 ms）和宽QRS（≥130ms）组。我们比较了CRT的响应率，并调查了年龄，性别，基线纽约心脏协会（NYHA）等级，缺血性病因，房颤和室性心律失常是否与响应相关，并且也可预测死亡率。结果。宽QRS组和窄QRS组之间的CRT响应率无显着差异（74.6％对77.2％， = 0.6876），而窄QRS组中的CRT响应率与世界范围内报道的一样好。NYHA IV级被证明是死亡率的预测指标（HR 9.38，95％CI 5.35-16.3， <0.0001）。结论。本研究表明，QRS复合体狭窄的患者对CRT的反应良好。即使QRS <130 ms，如果没有其他有效的治疗方法，也应尝试CRT。