CI-452766-2 RESULT OF THE PHYSIOLOGICAL PACING REGISTRY, AN INTERNATIONAL MULTICENTER PROSPECTIVE OBSERVATIONAL STUDY OF CONDUCTION SYSTEM PACING

Conduction system pacing (CSP), including both left bundle branch area (LBBAP) and His (HBP) has been proposed as an alternative therapy option in patients (pts) indicated for cardiac to treat bradycardia or heart failure. Evaluate implant success, safety, electrical performances of LBBAP HBP. International prospective observational study included 44 sites from 16 countries globally. The first enrollment occurred November 2018, the last May 2021. Most CSP leads were 2088 TC (Abbott, US) 3830 (Medtronic, US). 870 pts (mean age 75 yrs, female 39%) enrolled, lead implantation was attempted 849 pts. Pts followed 6 months. majority (84.8%) a single- dual-chamber pacemaker, 12.4% resynchronization therapy, 2.8% implantable cardioverter defibrillator. successful 768 (90.4%). Implant success 95.2% (239/251) 88.5% (529/598) HBP (p=0.002). with acceptable capture threshold defined ≤3V at ≤1.0ms immediately post-procedure 94.0% (236/251) 78.6% (470/598) (p<0.001). median (QR) procedure duration 66 (52-88) minutes 68 (50-95) (p=0.233), fluoroscopy 8 (5-14) 9 (5-15) (p=0.537). mean 0.69±0.39 V 1.44±1.03 (p<0.001) using pulse width (PW) 0.46±0.15 ms 0.71±0.33 months 0.79±0.33 1.59±0.97 PW 0.44±0.13 0.67±0.31 A rise ≥1V observed follow-up 3/208 (1.4%) 55/418 (13.2%) In 5±2 months, serious adverse event related 7/251 (2.8%) 26/598 (4.3%) (p=0.335). This large multicenter demonstrates that is technically feasible many patients, relatively high rates. Capture lower compared HBP, but there no significant difference events between two approaches.