A beginner's guide to permanent left bundle branch pacing

Abstract

Introduction Studies have demonstrated the feasibility and clinical benefits of permanent His-bundle pacing (HBP). However, concerns regarding higher pacing thresholds, lower R-wave amplitudes, and the potential to develop distal conduction block have limited the clinical application of HBP in certain subgroups. Thus, left bundle branch pacing (LBBP) has emerged as an alternative method for delivering physiological pacing to achieve electrical synchrony of the left ventricle (LV), especially in patients with infranodal atrioventricular block and left bundle branch block (LBBB). The proximal left bundle branches run through the LV septum and fan out to form a wider target for pacing compared to the His bundle. Recently, we reported that HBP can correct classic LBBB in 97% of patients, and Upadhyay et al demonstrated that the site of block usually is located within the His or proximal left bundle. We developed a technique for LBBP using a transseptal approach. LBBP has been reported to offer low pacing thresholds and large R waves, and because the distal conduction system is targeted, has a lower theoretical risk for development of distal conduction block. However, the definitions and implantation procedure have not been previously well described. Here we describe our method for performing LBBP to confirm intraseptal left con-