Permanent HBP was feasible and safe in a large real-world population requiring permanent pacemakers. His bundle pacing was associated with reduction in the combined endpoint of death, HFH, or upgrade to BiVP compared to RVP in patients requiring permanent pacemakers.

BACKGROUND His bundle pacing (HBP) is the most physiologic form of pacing but associated with higher thresholds and lower success in patients with His-Purkinje conduction disease. Recent reports have described transvenous left bundle branch area pacing (LBBAP). OBJECTIVE We aimed to prospectively evaluate the feasibility and the electrophysiologic and echocardiographic characteristics of LBBAP. METHODS Patients requiring pacing for bradycardia or heart failure indications (failed left ventricular [LV] lead) were prospectively enrolled. LBBAP was performed with a Medtronic 3830 lead. Presence of left bundle branch (LBB) potential, paced QRS morphology/duration, and peak LV activation time (pLVAT) were recorded at implant. Pacing threshold and sensing was assessed at implant and follow-up. Echocardiography was performed to assess the approximate lead location and impact on tricuspid valve function. RESULTS LBBAP was successful in 93 of 100 (93%) patients. Mean age was 75 6 13 years; men 69%, left bundle branch block 24%, right bundle branch block 25%, intraventricular conduction defect 8%. Indications for pacing were atrioventricular (AV) block 54%, sinus node dysfunction 23%, AV node ablation 7%, cardiac resynchronization therapy 11%, HBP lead failure 7%. Baseline QRS duration was 133 6 35 ms. Paced QRS duration was 136 6 17 ms. LBB potentials were observed in 63 patients with left bundle branch-ventricle (LBB-V) interval of 27 6 6 ms. pLVAT was 75 6 16 ms. Pacing threshold at implant was 0.6 6 0.4 V @ 0.5 ms and R waves were 10 6 6 mV and remained stable at median follow-up of 3 months. The lead depth in the septum was approximately 1.4 6 0.23 cm. CONCLUSIONS LBBAP was feasible in a high percentage of patients with low thresholds during acute follow-up. HBP and LBBAP may significantly increase the overall success of physiologic pacing.

No abstract

BACKGROUND The His-SYNC pilot trial was the first randomized comparison between His bundle pacing in lieu of a left ventricular lead for cardiac resynchronization therapy (His-CRT) and biventricular pacing (BiV-CRT), but was limited by high rates of crossover. OBJECTIVE To evaluate the results of the His-SYNC pilot trial utilizing treatment-received (TR) and per-protocol (PP) analyses. METHODS The His-SYNC pilot was a multicenter, prospective, single-blinded, randomized, controlled trial comparing His-CRT vs BiV-CRT in patients meeting standard indications for CRT (eg, NYHA II-IV patients with QRS .120 ms). Crossovers were required based on prespecified criteria. The primary endpoints analyzed included improvement in QRS duration, left ventricular ejection fraction (LVEF), and freedom from cardiovascular (CV) hospitalization and mortality. RESULTS Among 41 patients enrolled (aged 64 6 13 years, 38% female, LVEF 28%, QRS 168 6 18 ms), 21 were randomized to His-CRT and 20 to BiV-CRT. Crossover occurred in 48% of His-CRT and 26% of BiV-CRT. The most common reason for crossover from His-CRT was inability to correct QRS owing to nonspecific intraventricular conduction delay (n 5 5). Patients treated with His-CRT demonstrated greater QRS narrowing compared to BiV (125 6 22 ms vs Funding: None. Conflicts of Interest: Dr Gaurav Upadhyay has been a speaker for Abbott, Biotronik and Medtronic, and has been a consultant to Abbott, Biotronik, and Medtronic. Dr Pugazhendhi Vijayaraman has been consultant to Abbott, Biotronik, Boston Scientific, and Medtronic; he also has a patent pending for a His delivery tool. Dr Hemal Nayak has been a speaker for Medtronic, Biotronik, and Boston Scientific. Dr Nishant Verma has been a speaker for Biotronik and Medtronic. Dr Gopi Dandamudi has been a speaker and consultant for Medtronic and serves on the advisory board for Biotronik. Dr Parikshit Sharma has been a speaker for Medtronic and has been a consultant for Abbott and Biotronik. Dr Moeen Saleem has been a speaker for Abbott, Medtronic, and Boston Scientific. Dr Faiz Subzposh has been a consultant to Medtronic. Dr Zaid Aziz has been a speaker for Biotronik. Dr Richard Trohman has been a speaker for Abbott, AltaThera Pharmaceuticals, Boston Scientific, Daiichi Sankyo, and Medtronic; he has been an advisor to Boston Scientific; he has received research grants from

No abstract