Deep Septal Pacing for Pacemaker-Induced Cardiomyopathy.

Introduction: Right ventricular (RV) pacing can impair left ventricular function and cause heart failure, known as pacing-induced cardiomyopathy (PICM). Upgrade to cardiac resynchronization (CRT) is its usual treatment; recently left bundle branch area pacing (LBBAP) has emerged as a potential alternative. Deep septal pacing (DSP), a simplified alternative to LBBAP, is still able to achieve narrower paced QRS than during conventional RV pacing. The aim of this study was to assess the effect of DSP in a cohort of patients with PICM.

Methods and results: Consecutive patients diagnosed with PICM were included. The aim was to upgrade patients to DSP. The procedure was considered successful if a paced QRS duration ≤140 ms was obtained, in the absence of a terminal R wave in V1. Twelve patients were included. The mean baseline LVEF was 33% (SD 4%), and the mean percentage of RV pacing was 99% (SD 1%). All patients had symptomatic heart failure. The mean paced QRS duration was 172 ms (SD 14 ms) with RV pacing, and 130 ms (SD 7 ms) with DSP (mean difference 42 ms, p < 0.001). At 6 months, the mean LVEF after the upgrade was 46% (SD 9%), significantly superior to LVEF with RV pacing (p = 0.001), a mean improvement of 13% (SD 10%). All patients except one experienced an improvement in LVEF of at least 5%.

Conclusions: Our data suggest that DSP may be an effective and simpler alternative to biventricular or LBBAP in patients with PICM. Narrower paced QRS complexes can be achieved, which may lead to an improvement in left ventricular function.