Conduction System Pacing Versus Biventricular Pacing for Cardiac Resynchronization Therapy: A Systematic Review and...

Conduction system pacing (CSP) is an emerging alternative to biventricular pacing (BVP) for cardiac resynchronization therapy (CRT). Recent randomized controlled trials (RCTs) have yielded divergent results, creating uncertainty about the comparative effectiveness.

We performed a systematic review and meta-analysis of RCTs comparing CSP with BVP for CRT, searching PubMed, Embase, and CENTRAL through May 2026 (updating a prior review). The primary outcome was change in left ventricular ejection fraction (ΔLVEF), analyzed with random-effects models and prediction intervals.

Eight parallel-group RCTs including 799 patients (396 CSP, 403 BVP) were included. Pooled ΔLVEF did not differ significantly (MD +2.40%, 95% CI -0.49 to 5.29, p = 0.091; I ² = 75%). CSP showed a non-significant trend toward shorter paced QRS (MD -7.6 ms, p = 0.14) and improved NYHA class (SMD -0.33, p = 0.12). Heart failure hospitalization (RR 0.69), mortality (RR 1.17), complications (RR 0.84), and procedure time did not differ. The four trials enrolling exclusively LBBB patients favored CSP (MD +5.00%, 95% CI 3.01 to 6.98, p = 0.004; I ² = 0%), consistent in the three using confirmed LBBAP/LBBP (MD +5.37%, 95% CI 3.23 to 7.52, p = 0.008; I ² = 0%).

In this analysis of randomized trials of CRT, no statistically significant difference was observed between CSP and BVP for any outcome. Because no non-inferiority margin was prespecified and the clinical-event analyses were underpowered, these findings should not be interpreted as establishing equivalence or comparable safety. Exploratory analyses suggest that patients with LBBB undergoing LBBAP/LBBP may derive incremental benefit, warranting confirmation in adequately powered trials.