His-Purkinje Conduction System Pacing Optimized Trial of Cardiac Resynchronization Therapy vs Biventricular Pacing

His-Purkinje conduction system pacing (HPCSP) using His bundle pacing (HBP) or left bundle branch pacing (LBBP) has emerged as an alternative to biventricular pacing (BVP) in patients requiring cardiac resynchronization therapy (CRT). The aim of the study was to compare the feasibility and clinical efficacy of HPCSP-guided CRT (HOT-CRT) with BVP in patients with heart failure, reduced ejection fraction, and indication for CRT. This was a prospective, randomized, controlled trial of HOT-CRT and BVP in patients with LVEF <50% and indications for CRT. If HPCSP resulted in incomplete electrical resynchronization, a coronary sinus (CS) lead was added. The primary outcome was the change in left ventricular ejection fraction (LVEF) at 6 months. The primary safety endpoint was freedom from major complications. One hundred patients (female 31%, aged 70 ± 12 years, LVEF 31.5 ± 9.0%) were randomized. HOT-CRT was successful in 48 of 50 (96%) and BVP-CRT in 41 of 50 (82%) patients (P = 0.03). QRS duration significantly decreased from 164 ± 26 to 137 ± 20 ms with HOT-CRT and 166 ± 28 to 141 ± 19 ms with BVP. Fluoroscopy results (18.8 ± 12.4 vs 23.8 ± 12.4 min, P = 0.05) and procedure duration (119 ± 42 vs 114 ± 36 min, P = 0.5) were similar. The primary outcome of change in LVEF at 6 months was greater in HOT-CRT than in BVP (12.4 ± 7.3% vs 8.0 ± 10.1%, P = 0.02). The primary safety endpoint was similar (98% vs 94%, P = 0.62). Echocardiographic response of improvement in LVEF >5% occurred in 80% vs 61% (P = 0.06). Complications occurred in 3 (6%) in HOT-CRT vs 10 (20%) in BVP (P = 0.03). HPCSP-guided CRT resulted in greater change in LVEF compared with BVP. Randomized clinical trials with long-term follow-up are necessary. (His-Purkinje Conduction System Pacing Optimized Trial of Cardiac Resynchronization Therapy [HOT-CRT] NCT04561778)