Electrophysiological parameters and anatomical evaluation of left bundle branch pacing in an in vivo canine model

• Published in: Journal of cardiovascular electrophysiology 2020-01, Vol.31 (1), p.214-219
• Main Authors: Chen, Xueying, Jin, Qinchun, Li, Bingyu, Jia, Jianguo, Sharma, Parikshit S., Huang, Weijian, Su, Yangang, Ge, Junbo
• Format: Article
• Language: English
• Subjects: anatomical evaluation; Bundling; canine model; Conduction; conduction system pacing; EKG; electrocardiogram; Electrocardiography; Heart; His bundle pacing; Iodine; left branch bundle pacing; Lugol's iodine; Ventricle
• ISSN: 1045-3873; 1540-8167
• DOI: 10.1111/jce.14300

Introduction Left bundle branch pacing (LBBP), a form of conduction system pacing in addition to His bundle pacing (HBP), can potentially maintain left ventricular electrical synchrony with better sensing and a low and stable capture threshold. Methods We performed both HBP and LBBP using a canine model (n = 3; male; weight 30‐40 kg). The electrocardiogram (ECG), intracardiac electrogram characteristics, and pacing parameters were compared between HBP and LBBP. The hearts were isolated and stained by Lugol's iodine (5%) to assess the relative locations of the leads in relation to the conduction system. Results The average potential to ventricle interval was longer with HBP compared to LBBP (26.67 ± 3.06 ms vs 12.67 ± 1.15 ms; P = .002). There were also notable differences in the pacing parameters between HBP and LBBP: R‐wave amplitude (2.67 ± 0.42 mV vs 11.33 ± 3.06 mV; P = .008), pacing impedance (423.3 ± 40.4 vs 660.0 ± 45.8; P = .003), and threshold (2.30 ± 0.66 V/0.4ms vs 0.67 ± 0.15 V/0.4 ms; P = .014). The paced morphology of ECG was similar to the intrinsic with HBP while a right bundle branch block pattern was noted with LBBP. The anatomical evaluation revealed the location of the leads and the average lead depth was significantly more with LBBP as compared to HBP (12.33 ± 1.53 mm vs1.83 ± 0.29 mm; P