Comparing left bundle branch area versus right ventricular septal pacing in high-degree conduction disease after TAVR: Randomized trial study protocol Left Bundle BRAVE: Study protocol.

Left bundle branch area pacing (LBBAP) is a novel method of conduction system pacing in the muscular interventricular septum. While LBBAP has been shown to produce physiologic electrical and mechanical intraventricular synchrony, the superiority of LBBAP at preserving normal left ventricular systolic function compared to right ventricular septal pacing (RVSP) after transcatheter aortic valve replacement (TAVR) has not been demonstrated.Left Bundle BRAVE is an investigator-initiated, multicenter, prospective, double-blinded, randomized, crossover study investigating the superiority of LBBAP compared to right ventricular septal pacing (RVSP) with respect to preservation of systolic function in patients with high-degree conduction disease after transcatheter aortic valve replacement (TAVR). Adults with severe aortic stenosis (AS) and normal systolic function who sustain high-grade AV block within four weeks of TAVR are eligible. All subjects receive a Medtronic (Medtronic, Minneapolis, MN) biventricular pacemaker generator, RVSP and LBBAP leads. Participants are randomly assigned to 9 months of each pacing mode in series. The primary endpoint is change in global longitudinal strain (GLS%) tested in series with change in left ventricular ejection fraction (LVEF) comparing RVSP to LBBAP. Secondary endpoints include echocardiographic markers of interventricular synchrony and right ventricular performance, heart failure functional status and symptom classification, 6 Minute Walk Test, pacemaker and lead performance, and brain natriuretic peptide (BNP) concentration.Left Bundle BRAVE is designed to identify an upstream and clinically relevant marker of superiority in LBBAP compared to RVSP at preventing deterioration of left ventricular function in patients with high ventricular pacing burden after TAVR. ClinicalTrials.gov identifier: NCT05541679