A high BNP level predicts an improvement in exercise tolerance after a successful catheter ablation of persistent atrial fibrillation

Introduction: Restoration of sinus rhythm (SR) by catheter ablation (CA) of atrial fibrillation (AF) improves exercise tolerance. However, it is still unclear what characteristics of patients are contributing to an improvement in exercise tolerance after CA of AF without heart failure. Methods and results: This study consisted of 51 consecutive patients with persistent or long-standing persistent AF without heart failure who were restored to SR for over 6 months by a successful CA. Exercise tolerance was evaluated by cardiopulmonary exercise testing before and 3 and 6 months after CA. The clinical characteristics contributing to an improvement in exercise tolerance was elucidated. The peak oxygen uptake (VO₂)% significantly increased from 101.4 ± 20.3% to 110.9 ± 19.9% 3 months after the CA (P <.001). The improvement rate in the peak VO₂% exhibited a positive correlation to the baseline brain natriuretic peptide (BNP; ρ = 0.39, P <.01), but not to the age, AF duration, left ventricular ejection fraction, or left atrial size. The linear regression analysis revealed that the baseline BNP was an independent predictor of an improvement in the peak VO₂% (coefficients = 0.32; 95% confidence interval = 0.08, 0.54; P =.01). The peak VO₂% improved significantly in the patients whose baseline BNP level was greater than 100 pg/mL, compared to the others (P <.01). These favorable findings were also observed 6 months after the CA. Conclusion: Elimination of persistent AF by CA was associated with an improvement in exercise tolerance. This was particularly true in patients with high BNP values at baseline.