Conduction system versus biventricular pacing in heart failure with non-left bundle branch block

Area of Science:

• Cardiology
• Electrophysiology
• Heart Failure Management

Background:

• Cardiac resynchronization therapy (CRT) benefits are reduced in heart failure (HF) patients with non-left bundle branch block (LBBB) conduction delay.
• Biventricular pacing (BiV) is the standard CRT, but its efficacy is limited in non-LBBB HF.
• Conduction system pacing (CSP) offers a potential alternative for CRT in this patient group.

Purpose of the Study:

• To investigate the clinical outcomes of CSP as a CRT strategy in HF patients with non-LBBB conduction delay.
• To compare the efficacy of CSP versus traditional BiV pacing in this specific HF population.

Main Methods:

• A propensity-matched analysis comparing 96 consecutive HF patients with non-LBBB undergoing CSP to BiV recipients.
• Patients were matched for age, sex, HF etiology, and atrial fibrillation (AF).
• Primary outcome: composite of HF hospitalizations or all-cause mortality. Echocardiographic response defined as ≥10% increase in LVEF.

Main Results:

• CSP significantly reduced QRS duration and LV dimensions, unlike BiV.
• Echocardiographic response (LVEF improvement) was more frequent with CSP (51%) than BiV (21%).
• CSP was associated with a 58% reduction in the primary outcome (HF hospitalization or all-cause mortality), driven by reduced all-cause mortality.

Conclusions:

• CSP demonstrates superior electrical synchrony, reverse remodeling, and improved cardiac function compared to BiV in non-LBBB HF patients.
• CSP is associated with significantly better survival outcomes.
• CSP may represent a preferred CRT strategy for heart failure patients with non-LBBB conduction delay.