LAUSR

In advanced heart failure patients with low left ventricular ejection fraction and left bundle branch block (LBBB), cardiac resynchronization therapy (CRT) via stimulation of both the right ventricle (RV) and the left ventricular lateral wall is a recommended therapeutic strategy (1–3). However, conventional biventricular pacing causes a dyssynchronous cardiac contraction due to non-physiological fusion of paced propagation, with a non-response rate of up to 30% (4, 5). In 2016, Mafi-Rad et al. (6) established the viability of the left ventricular septal pacing (LVSP) via a trans-interventricular septal approach in 10 patients with sinus node dysfunction, which shortened QRS duration and preserved acute left ventricular contractility compared to RV pacing. Huang et al. refined LVSP and introduced first left bundle branch pacing (LBBP) in 2017 (7), which could restore physiological left ventricular contractility in a patient with LBBB by pacing left bundle branch (LBB) immediately beyond the conduction blockage with satisfactory pacing parameters. Many studies have demonstrated the feasibility and stability of LBBP in patients with pacemaker indications, and it has been proposed that LBBP is a novel physiological pacing method for delivering CRT for achieving electric resynchronization in patients with LBBB (8–10).