Intraprocedural Left Atrial Pressure Elevation and Risk of Heart Failure Events After Atrial Fibrillation Ablation

The clinical implication of left atrial pressure (LAP) elevation during atrial fibrillation (AF) ablation remains uncertain.

We retrospectively analyzed 189 patients undergoing their first AF thermal ablation. LAP was measured via the transseptal sheath at insertion (initial) and withdrawal (final), showing a median intraprocedural elevation of 4 mmHg (interquartile range 1-6). Patients were dichotomized by the median intraprocedural change (high LAP increase: ≥4 mmHg, n=95; low LAP increase: <4 mmHg, n=94). The primary endpoint was heart failure (HF) hospitalization within 1 year, and the secondary endpoint included identifying predictors with a high LAP increase. Procedural characteristics were similar. Although initial LAP values were comparable between groups, patients with a high LAP increase exhibited higher right atrial pressure (RAP) and RAP/LAP ratio (0.9±0.3 vs. 0.7±0.2; P<0.001). The cumulative incidence of HF hospitalization was significantly higher in the high LAP increase group (8.5% [95% confidence interval (CI) 2.7-13.9] vs. 1.1% [95% CI 0-3.2]; P=0.020). On multivariate analysis, female sex, persistent AF, higher body mass index, higher initial RAP/LAP ratio, and structural heart disease were independent predictors of a high LAP increase.

Intraprocedural LAP elevation was associated with a higher risk of HF hospitalization within 1 year after the procedure. Monitoring LAP at both the start and end of ablation provides a feasible approach for post-procedural risk stratification.