Step-By-Step Left Bundle Branch Area Pacing: A Practical Technical Guide.

Left bundle branch area pacing (LBBAP) has emerged as a physiological pacing strategy capable of restoring ventricular synchrony in patients requiring permanent pacing or cardiac resynchronization therapy (CRT). Compared with conventional right ventricular pacing and biventricular pacing, LBBAP provides more physiological ventricular activation by engaging the His-Purkinje conduction system. However, procedural success depends heavily on appropriate patient selection, anatomical targeting, and standardized implantation techniques. This technical review aims to provide a comprehensive, step-by-step guide to LBBAP implantation by integrating electrocardiographic, fluoroscopic, and intracardiac electrophysiological criteria consistent with current European Heart Rhythm Association (EHRA) and Heart Rhythm Society (HRS) recommendations. It summarizes the procedural workflow, patient selection criteria, implantation techniques, electrocardiographic markers, septal penetration strategies, and pacing confirmation parameters based on selected implantation cases supported by annotated electrocardiograms (ECGs), filtered and unfiltered electrograms (EGMs), and fluoroscopic images. Key procedural elements associated with successful LBBAP include systematic evaluation of the interventricular septal anatomy, continuous 12-lead ECG monitoring, precise fluoroscopic targeting, and electrophysiological confirmation of conduction system capture. Important procedural indicators include a W-pattern morphology in lead V1 and aVR-aVL discordance before septal penetration, fixation beats during septal penetration, a terminal r/R wave in lead V1, the V6 R-wave peak time, V6-V1 interpeak interval measurements, and demonstration of selective or nonselective left bundle branch capture or left ventricular septal capture after septal penetration. When performed using standardized implantation criteria and electrophysiological validation, LBBAP represents a reproducible and effective physiological pacing technique for both bradycardia indications and CRT candidates. The adoption of standardized procedural terminology and validation criteria may improve procedural success and clinical outcomes.