First-in-human study of a leadless pacemaker system for left bundle branch area pacing

Background Leadless pacemakers (LPs) are limited by the current inability to perform left bundle branch area pacing (LBBAP). Objective The purpose of this first-in-human acute feasibility study was to evaluate the safety and performance of a novel helix-based LP with an extended electrode for LBBAP (LP CSP ). Methods After obtaining informed consent, the LP CSP (Aveir CSP LP) was temporarily deployed in patients with indications for LP implantation. The LP CSP was introduced from the right internal jugular (IJ) vein and temporarily implanted deep into the interventricular septum (IVS) under fluoroscopic and intracardiac echocardiographic guidance. The primary safety endpoint was freedom from serious device adverse events (SADEs) within 1 month of the implant procedure. The primary performance endpoints were intraprocedural electrical parameters, including pacing threshold, impedance, and sensed R-wave amplitude. The LP CSP then was removed, and a conventional LP was implanted in the right ventricle using the same IJ access. Results Among 14 enrolled patients (age 69.4 ± 9.9 years, 71% male), the LP CSP was successfully implanted into the IVS in 10 patients. Pacing threshold (1.2 ± 0.6 V at 0.4 ms), R-wave amplitude (10.2 ± 4.1 mV), and impedance (373 ± 56 Ω) were acceptable. LBBAP capture was observed in 5 patients, segmented into direct capture of the left bundle branch (n = 1) and left ventricular septal pacing (n = 4). Deep septal pacing was observed in 3 additional patients. Freedom from SADEs within 1 month of the implant procedure was 85.7%. Conclusion This first-in-human study demonstrated acute successful implantation of the LP CSP with clinically acceptable intraprocedural electrical performance and safety.