Introduction
Right ventricular (RV) apical pacing has remained the standard approach to ventricular pacing despite evidence that it causes electrical dyssynchrony associated with an increased risk of developing atrial fibrillation and left ventricular systolic dysfunction.1-4 The current popularity of RV apical pacing as the preferred pacing site is driven primarily by the ease of placing pacing leads into the apex, as well as the stability of pacing parameters at this location. In recent years, “physiological” approaches to pacing have attracted significant interest as electrophysiologists seek to maintain left ventricular synchrony and mitigate the adverse effects of RV apical pacing. Though His-bundle pacing (HBP) had emerged as a promising approach to physiologic pacing, HBP can be technically challenging to perform using current tools.5-10 Furthermore, HBP has been associated with a high incidence of rising pacing thresholds and low sensing values. Indeed, unacceptable pacing parameters over time can mandate lead revision and/or generator replacement for pre-mature battery depletion. Together, these serve as major deterrents to the adoption of physiologic pacing when compared to traditional RV apical pacing.11-14
More recently, left bundle branch area pacing (LBBAP) has emerged as an attractive alternative to achieving physiologic pacing – particularly since initial studies have not reported rising pacing thresholds or reduced sensing values.15-19 As operators begin to explore physiologic pacing strategies in their practice, it is unclear whether one should pursue HBP, LBBAP or a combination of the two strategies. In this study, we compared procedural outcomes and intermediate follow-up for the first 50 patients at our institution undergoing either HBP or LBBP. By sharing this early experience with both approaches to physiological pacing, we aim to highlight the challenges one may experience with the adoption of physiological pacing.