Comparison of Electrophysiological Left Bundle Branch Pacing Characteristics in Different Bilateral Electrode Pacing Vector Configurations

Abstract

Background: Left bundle branch pacing (LBBP) in bipolar pacing produces a more balanced ventricular activation than conventional unipolar pacing but need high pacing output.

Objective: The present study aimed to compare the electrophysiological characteristics of LBBP in different bilateral electrode pacing vector configurations.

Methods: A total of 57 patients who met the criteria for left bundle branch (LBB) capture and underwent three bilateral electrode pacing vector configuration test were enrolled. The electrocardiogram (ECG) and electrogram (EGM) parameters were evaluated and other electrophysiological characteristics were analyzed using a three-electrode configuration test.

Results: Seven capture modes (right ventricular septal (RVS) + left ventricular septal (LVS) + LBB, RVS + LBB, LVS + LBB, RVS + LVS, RVS, LVS, and LBB) were utilized in the study. The thresholds of full fusion mode (RVS+LVS+LB) in Bilateral Cathodes and Ring Bipolar were all lower than that in Tip Bipolar (1.2 ± 0.5 V vs. 2.7 ± 1.0 V, P < 0.001; 1.6 ± 0.6 V vs. 2.7 ± 1.0 V, P < 0.001). Full fusion mode had the shortest P-QRS (116.9 ± 12.8 ms), V6 RWPT (64.9 ± 9.7 ms), and V1 RWPT (94.5 ± 12.3 ms).

Conclusion: Changing the bilateral electrode pacing vector configuration to Bilateral Cathodes and Ring Bipolar can reduce the full fusion mode capture threshold compared to conventional bipolar pacing.

Note:
Funding Information: This work was supported by the Zhejiang Provincial Public Service and Application Research Foundation, China [grant number LGF22H020009], the Ningbo Health Branding Subject Fund [grant number PPXK2018-01] and Medical Scientific Research Foundation of Zhejiang Province, China [grant number 2022KY1122].

Declaration of Interests: We declare that we do not have any commercial or associative interest that represents a conflict of interest in connection with the work submitted.

Ethical Approval Statement: The study protocol was approved by the hospital institutional review board (SL-KYSB-NBEY-2021- 94 079-01), and all patients provided written informed consent.

Keywords: Left bundle branch pacing, Bipolar pacing, Conduction system pacing, Capture threshold, Electrode configuration