Conduction system pacing versus biventricular pacing for cardiac resynchronization therapy: frequentist and bayesian meta-analysis of randomized controlled trial and propensity matched studies

BACKGROUND: Cardiac resynchronization therapy (CRT) with biventricular (BiV) pacing is non-physiological, and a third of patients do not respond. OBJECTIVE: This study aimed to compare conduction system pacing (CSP) with BiV. METHODS: Systematic searching of databases was conducted to include RCTs and comparative propensity-matched studies. CSP includes left bundle branch pacing (LBBP), his bundle pacing (HBP), and HOT/ LOT CRT (optimized HBP/ LBBP). Frequentist and Bayesian meta-analyses were performed. RESULTS: Twenty-eight studies (13 RCTs) with 5524 patients were included. CSP was associated with better CRT response (OR 1.69, CI: 1.20-2.39; p = 0.0027) and better clinical response (OR 1.83, CI: 1.12-2.99; p = 0.01). CSP was associated with lower odds of composite outcomes (OR 0.51, CI: 0.30-0.88, p = 0.01), HF hospitalization (OR 0.58, CI: 0.35-0.96; p = 0.0347), and all-cause mortality (OR 0.67, CI: 0.46-0.97, p = 0.0340). CSP was also associated with significantly higher improvement in QRS duration, LVEF, LVESD, NT-pro BNP, NYHA, and 6MWD (all p < 0.05). Bayesian meta-analysis consistently favoured CSP across all clinical outcomes, with probability of meaningful benefit exceeding 90% for CRT response, super-response, composite outcome, and HF hospitalization. However, RCT-only analysis yielded inconsistent results across most outcomes, with only clinical response remaining statistically significant. In subgroup analyses, LBBP appears to have the most benefit across CRT response and HF hospitalization outcomes. CONCLUSION: CSP may offer potential advantages over BiV pacing in patients indicated for CRT; however, confirmation in larger randomized clinical trials is required.