Performance of an active fixation stylet-driven lead in left bundle branch area pacing: Results from INSIGHT-LBBA

Background: Left bundle branch area pacing (LBBAP) has been rapidly adopted despite a lack of leads with approved indications for LBBAP. Objective: This study aims to analyze the performance of a 6Fr active fixation, stylet-driven lead in LBBAP. Methods: The multicenter INSIGHT-LBBA registry analyzed consecutive LBBAP implant attempts with INGEVITY+ leads. Data were retrospectively collected with standardized entry via REDCap. Prespecified safety (lead-related complication [LRC]-free rate with performance goal >90% at 3 months) and effectiveness (pacing capture threshold [PCT] ≤2 V@ 0.4 ms and R-waves ≥5 mV; 3-month performance goal = 80%) endpoints were analyzed. External validation of lead effectiveness was performed on a separate cohort of LBBAP patients from the LATITUDE remote monitoring database. Results: The study enrolled 1122 single- or dual-chamber pacemaker patients from 8 US sites (mean age 76 ±10 years, 43% female, 48% atrioventicular [AV] block, 40% sinus node dysfunction). Those successfully implanted had a median follow-up of 302 days. Left bundle or left septal capture was achieved in 95.6% of patients (1073 of 1122) and 89.6% of leads (1073 of 1197, 1.07 leads per patient). The 3-month LRC-free rate was 97.7% (lower confidence limit [LCL] 96.6%) with an LRC-free rate of 97.2% at 24 months. At 3 months, 98.8% (LCL 97.7%) of PCTs were ≤2 V, and 94.8% (LCL 92.7%) of sensed amplitudes were ≥ 5 mV. Results were stable through 24 months; 864 LBBAP implants were analyzed in the external validation cohort, and lead effectiveness was clinically indistinguishable across datasets. Conclusion: In this study of an active fixation, stylet-driven lead, all prespecified performance goals for pacing, sensing, and LRC rates were met when used for LBBAP. External validation demonstrated concordant results.