Abstract 11448: Feasibility and Septal Perforation Rates in Left Bundle Branch Area Pacing

Abstract

Introduction: Left Bundle Branch area Pacing (LBBaP) is gaining prevalence as a more physiologic alternative to conventional right ventricular pacing. Given limited literature on LBBaP, this retrospective study assessed feasibility and septal perforation rates following LBBaP. Methods: Procedure reports and electrophysiologic parameters were reviewed of patients that underwent LBBaP since 2019. Partial septal perforation was defined as any two of: a) reduction of impedance by 200 ohms b) increase in capture threshold by 50% and c) decrease in ventricular sensing by 50% during follow-up compared to approximately 1-week post pacemaker implant. Results: Since 2019, LBBaP was attempted in 168 patients and was successful in 102 (60.7 %), partial successful in 55 (32.7%) defined as QRS reduction of >20ms and duration <140ms, and unsuccessful in 11 (6.6%). QRS duration shortened or remained short after successful LBBaP compared to unsuccessful (113 vs 147 ms, p < 0.001). Left ventricular ejection fraction was similar following successful LBBaP (p = 0.92). Five patients (3%) had potential septal perforation based on above criteria. Lead revisions were not arranged for these patients as pacing requirements were not high and it was clinically appropriate to continue 3 monthly observations in clinic. Conclusions: We report success rates of LBBaP recently adopted in a large tertiary center. In a medium-term follow-up, we show that changes in electrophysiologic parameters likely consistent with partial septal perforation may occur spontaneously in some patients (3% in our cohort) over time. Clinical significance of these changes and confirmation with imaging requires further study.