Clinical Outcomes and Electrophysiological Characteristics of Partial Perforation After Left Bundle Branch Area...

Septal perforation, defined as partial or complete protrusion of a lead helix, is a potential complication of left bundle branch area pacing, theoretically increasing risks of pacing failure and thromboembolism. However, no studies have examined the long-term prognosis of patients with partial perforations (PPs).

This study aimed to elucidate the incidence, outcomes, and electrophysiological characteristics of PP in clinical and experimental swine studies.

Patients requiring pacing who underwent successful left bundle branch area pacing were retrospectively included. PP was identified using postoperative echocardiography. Clinical outcomes, including all-cause mortality, thromboembolism, and lead-related complications, were compared between the PP and non-PP groups. Waveforms from the nonfiltered unipolar electrogram (NF-EGM) recorded at the lead tip were evaluated to identify morphology specific to PP.

Of the 95 patients, PP was confirmed in 25 (26.3%), occurring only in patients with left bundle branch capture, with an incidence rate of 41.7%. Event-free survival rates were comparable between the PP and non-PP groups at a median follow-up of 24 months (log rank, P = 0.298). No thromboembolisms or lead-related complications occurred in the PP group. The type-QS and type-R morphologies of NF-EGM reliably identified and excluded PP, respectively, as validated in swine heart experiments.

This study found that PP is not associated with an increased risk of adverse clinical outcomes. Deep septal lead deployment utilizing the NF-EGM morphology would be useful in recognizing and avoiding PP intraoperatively.