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.
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.
Heart Rhythm. 2021 Jun;18(6):946-953. doi: 10.1016/j.hrthm.2021.03.034. Epub 2021 Mar 27.
Left bundle branch pacing (LBBP) is an emerging physiological pacing modality. However, little is known about pacing at different locations on the left bundle branch (LBB).
The purpose of this study was to explore pacing and physiological characteristics associated with different LBBP locations.
The study included 68 consecutive patients with normal unpaced QRS duration and successful LBBP implantation. Patients were divided into 3 groups according to the paced QRS complex as left bundle branch trunk pacing (LBTP), left posterior fascicular pacing (LPFP), or left anterior fascicular pacing (LAFP). Electrocardiographic (ECG) characteristics, pacing parameters, and fluoroscopic localization were collected and analyzed.
There were 17 (25.0%), 35 (51.5%), and 16 (23.5%) patients in the LBTP, LPFP, and LAFP groups, respectively. All subgroups had relatively narrow paced QRS complex (128.6 ± 9.1 ms vs 133.7 ± 11.2 ms vs 134.8 ± 9.6 ms; P = .170), fast left ventricular activation (70.4 ± 9.0 ms vs 70.6 ± 10.2 ms vs 71.0 ± 9.0 ms; P = .986), as well as low and stable pacing thresholds. Delayed right ventricular activation and interventricular dyssynchrony were similar between groups. Fluoroscopic imaging indicated that the lead tip was located most commonly in the basal-middle region of the septum (67.7%), and this was independent of paced QRS morphology group (88.2% vs 57.1% vs 68.8%; P = .106).
Pacing at different sites of the LBB resulted in similar intraventricular and interventricular electrical synchrony in patients with an intact conduction system. Fluoroscopic imaging alone could not predict specific LBBP paced ECG morphology.
左束支起搏（LBBP）是一种新兴的生理性起搏方式。然而，对于左束支（LBB）不同部位起搏的了解甚少。
本研究旨在探讨与不同 LBBP 部位相关的起搏和生理特征。
该研究纳入了 68 例 QRS 间期正常且成功植入 LBBP 的连续患者。根据起搏后的 QRS 波群形态，将患者分为左束支干起搏（LBTP）、左后间隔部起搏（LPFP）和左前间隔部起搏（LAFP）三组。收集并分析心电图特征、起搏参数和透视定位。
LBTP、LPFP 和 LAFP 组分别有 17 例（25.0%）、35 例（51.5%）和 16 例（23.5%）患者。所有亚组的起搏 QRS 波群均较窄（128.6 ± 9.1 ms 比 133.7 ± 11.2 ms 比 134.8 ± 9.6 ms；P =.170），左心室激活较快（70.4 ± 9.0 ms 比 70.6 ± 10.2 ms 比 71.0 ± 9.0 ms；P =.986），起搏阈值较低且稳定。各组间右心室激活延迟和室间不同步相似。透视成像显示，导丝尖端最常位于间隔的基底-中段（67.7%），与起搏 QRS 形态无关（88.2%比 57.1%比 68.8%；P =.106）。
在完整的传导系统患者中，LBB 的不同部位起搏导致相似的室内和室间电同步性。仅凭透视成像无法预测特定的 LBBP 起搏心电图形态。
