Shah Ankur R, Yazaki Kyoichiro, Seamons Benjamin, Offei Emmanuel, Castilo Sofia Ruiz, Li Hui, Khan Muhammad S, Hitchcock Robert, Ranjan Ravi, Dosdall Derek J
Nora Eccles Harrison Cardiovascular Research and Training Institute, The University of Utah, Salt Lake City, Utah.
Department of Biomedical Engineering, The University of Utah, Salt Lake City, Utah.
Heart Rhythm O2. 2025 May 8;6(7):1005-1010. doi: 10.1016/j.hroo.2025.04.012. eCollection 2025 Jul.
Left bundle branch area (LBBA) lead placement relies on single-electrode pacing guided by electrocardiogram markers during transeptal advancement. We hypothesize that multiple electrodes on a lead tip facilitate LBBA pacing.
This study aimed to develop and evaluate a multielectrode lead (MEL) with dimensions and electrical properties similar to clinically relevant lumenless leads (LLLs) for use in LBBA pacing.
Insulated 125 μm silver wires were fixed along a 3-dimensional printed MEL shaft. Wires were wrapped circumferentially at distal, medial, and proximal sites (0.4 mm apart), secured with polyimide, and deinsulated by sanding. The MEL tip was cut into a bevel shape to facilitate septal insertion. MEL has 5.4 mm surface area across the 3 electrodes vs LLL's 3.6 mm surface area. MELs and LLLs were inserted at up to 3 LBBA sites in perfused canine hearts (n = 4), totaling 9 sites. Impedance, pacing threshold, and shortest QRS duration at each insertion site were recorded and compared.
MEL and LLL had similar impedance and capture voltages. MEL's multiple pacing options evoked QRS morphology changes with pacing output and location. MEL more often detected a narrower QRS at insertion than LLL (LLL, 114 ms; quartile [Q]1-Q3, 98-120 ms; MEL, 82 ms; Q1-Q3, 68-98 ms; = .03) and recorded QRS durations similar to sinus rhythm, suggesting MEL may better facilitate physiological pacing.
MELs more often evoked electrocardiogram markers indicative of conduction system capture during LBBA pacing, suggesting that MELs may streamline implantation, reduce lead repositioning, and advance conduction system pacing strategies.
左束支区域（LBBA）导联放置依赖于经房间隔推进过程中由心电图标记物引导的单电极起搏。我们假设导联尖端的多个电极有助于LBBA起搏。
本研究旨在开发和评估一种多电极导联（MEL），其尺寸和电学特性与临床相关的无内腔导联（LLL）相似，用于LBBA起搏。
将绝缘的125μm银丝沿三维打印的MEL轴固定。导线在远端、中间和近端部位（相距0.4mm）进行圆周缠绕，用聚酰亚胺固定，并用砂纸去除绝缘层。MEL尖端切成斜面以利于房间隔插入。MEL在3个电极上的表面积为5.4mm²，而LLL的表面积为3.6mm²。将MEL和LLL插入灌注犬心脏的多达3个LBBA部位（n = 4），共9个部位。记录并比较每个插入部位的阻抗、起搏阈值和最短QRS持续时间。
MEL和LLL具有相似的阻抗和捕获电压。MEL的多种起搏选项随着起搏输出和位置的变化引起QRS形态改变。MEL在插入时比LLL更常检测到更窄的QRS（LLL，114ms；四分位数[Q]1-Q3，98-120ms；MEL，82ms；Q1-Q3，68-98ms；P = .03），并且记录的QRS持续时间与窦性心律相似，表明MEL可能更好地促进生理性起搏。
在LBBA起搏期间，MEL更常诱发指示传导系统捕获的心电图标记物，这表明MEL可能简化植入过程，减少导联重新定位，并推进传导系统起搏策略。
