AV Node Ablation (AVNA) with right ventricular or biventricular pacing (Conventional Pacing-CP) is an effective therapy for patients with refractory atrial fibrillation. Conduction System Pacing (CSP) using His bundle pacing or left bundle branch area pacing preserves ventricular synchrony and may be associated with better clinical outcomes.
Patients undergoing AVNA at a large health system between Jan 2015 and Oct 2020 were included in this retrospective observational study. CP or CSP were performed at the operators’ discretion. Procedural, pacing parameters and echocardiographic data were assessed. Primary outcome was the combined endpoint of time to death or heart failure hospitalization (HFH) and analyzed using Cox proportional hazards. Secondary outcomes were individual outcomes of death and HFH.
AVNA was performed in 223 patients (CSP 110; CP 113). Age 75±10 years, men 52%, hypertension 67%, diabetes 25%, coronary disease 40%, LVEF 43±15 % and baseline QRS duration 111±30ms. QRS duration increased from 103±30ms to 124±20ms (p<0.01) in CSP and 119±32ms to 162±24ms in CP. During a mean follow up of 27±19 months, LVEF significantly increased from 46.5±14.2% to 51.9±11.2% (p=0.02) in CSP and 36.4±16.1% to 39.5±16% (p=0.6) in CP. The primary outcome of death or HFH was significantly reduced in CSP compared to CP (48% vs 62%; HR 0.61, 95% CI 0.42-0.89, p<0.01). There was no significant reduction in the secondary outcomes of HFH and death in the CSP group compared to CP.