Abstract 11024: 3D Localization of Left Bundle Branch Area and Pacing Lead Orientation During Left Bundle Pacing

Introduction: Left bundle branch area (LBBA) pacing is a novel physiologic pacing technique where the pacing lead is inserted through the right ventricular (RV) septum to capture the LBBA. Among the challenges encountered are identifying the RV septal site, assessing the plane of the lead, determining the depth of insertion, and repositioning the lead to a new site if needed. Navik 3D is a unique localization system that can convert 2D fluoroscopy images into 3D. Methods: Following consent, we studied six consecutive patients with a mean age of 72 years who underwent LBBA pacing. Patient characteristics including female sex (n=2), mean body mass index (33.8 kg/m 2 ), mean left ventricle ejection fraction (51%), mean intraventricular diastolic thickness (1.06 cm), and presence of hypertension (n=4), diabetes (n=4) atrial fibrillation (n=4), and left bundle branch block (n=1). Patients presented with either complete heart block (n=4) or sinus node dysfunction (n=2). LBBA was localized on the RV septum using fluoroscopy and contrast injection. The RV septum, RV apex, lead position, and His locations were identified in 3D using 2D fluoroscopy from two different views. Then, 3D locations were projected on the 2D fluoroscopy image via the Navik 3D mapping system. The system could also mark an unsuccessful site and allow repositioning. Results: All patients had a successful placement in the LBBA with qR in V1, short mean left ventricular activation time (ms) in V6 (73.1), and left bundle potential was recorded in 3 patients. Conclusions: Localization of LBBA in 3D is feasible and may be useful for optimal lead placement.