Simplification of left bundle branch area pacing using a novel modified 3-lead pacing system analyzer electrocardiogram technique in the non-electrophysiology laboratory.

Background: An electrophysiology (EP) recording system is recommended throughout the left bundle branch area pacing (LBBaP) procedure. However, the requirement of an EP recording system limits the wide adoption of LBBaP in non-EP laboratory settings. Thus, in this study, we proposed a novel set-up in non-EP laboratories using manufacturer pacing system analyzer (PSA)-derived electrogram guidance and fluoroscopy of the angiography system for LBBaP.

Methods: Our study prospectively enrolled consecutive patients who underwent LBBaP for bradyarrhythmia indications. LBBaP was performed using a stylet-driven lead (SDL) delivered through a dedicated delivery sheath. Procedural characteristics were recorded at the implant. The agreement of measurements on the modified 3-lead ECG of PSA and standard 12-lead ECG was analyzed.

Results: A total of 83 patients were enrolled (mean age 65.4 ± 11.8 years, 55.4% male). The LBBaP with an SDL was successful for all patients. The pacing response was observed as LBBP in 69.9% of cases, while 30.1% were classified as left ventricular septal pacing. The mean paced QRS duration (pQRSd) and the stimulus to left ventricular activation time (LVAT) were measured at 117.6 ± 11.4 ms and 68 ± 17 ms using a modified 3-lead ECG of PSA, compared to 118.5 ± 11.8 ms and 70 ± 13 ms using the standard 12-lead ECG, with agreements of 0.89 and 0.93, respectively. SDL-LBBaP resulted in low unipolar and bipolar pacing thresholds (0.7 ± 0.2 V at 0.4 ms and 0.8 ± 0.2 V at 0.4 ms), which remained stable at a median 12-month follow-up (p > 0.05). An atrial lead revision was needed for one (1.2%) patient during the first-month visit. Acute interventricular septal perforation occurred in two (2.4%) patients as a specific complication of LBBaP.

Conclusion: Our novel setting in non-EP laboratories, utilizing fluoroscopy from the angiography system and manufacturer-modified 3-lead ECG and EGM of PSA during LBBaP, is feasible, reliable, and widely available. LBB capture was confirmed by both the standard EP recording system and new modified PSA 3-lead ECG measurements, which showed good agreement. Further large-scale data is needed to validate our findings.