B-type natriuretic peptide predicts recurrence of atrial fibrillation after pulmonary vein antral isolation

Abstract

Background: Recurrence of atrial fibrillation (AF) occurs in up to 25% of patients after pulmonary vein antral isolation (PVAI). Recently, B-type natriuretic peptide (BNP) and C-reactive protein (CRP) have been associated with AF. We aimed to test the hypothesis that elevated preablation BNP or CRP levels can predict the recurrence of AF post-PVAI. Methods: BNP and CRP levels were prospectively drawn on all patients before ablation on the day of the scheduled procedure. Follow-up was performed by weekly transtelephonic transmissions, even if asymptomatic, for 3 months and scheduled Holter monitoring at follow-up. Uniand multivariate analyses were performed on demographic, clinical and echo data, CRP and BNP to determine predictors of AF recurrence. For regression analysis log BNP and log CRP were used because these values were skewed. Results: Between 3/03 and 1/04, 521 patients underwent PVAI. After 280 136 days of follow-up 20% of patients (102/521) had recurrence of AF, defined as recurrence after 8 weeks post PVAI. There was no difference in gender distribution (25% vs 30% females), hypertension, LV function (55.8 8% vs 55.6 6%), left ventricular hypertrophy (LVH), left atrial size, history of coronary artery disease (CAD), beta-blocker or pre-procedural antiarrhythmic drug use between the patients who developed recurrence of AF and those who did not. Pre-op plasma BNP and CRP levels were higher in the recurrence group (median 87pg/ml vs 58 pg/ml, Inter Quartile Range, IQR, [44,195] vs [25,114], p 0.005 for BNP and 2.6 mg/l vs 2.1mg/l, IQR [1.15,5.5] vs [1.02,4.4] for CRP). In regression analysis that included age, gender, hypertension, LV function, LVH, left atrial size, CAD, drug use, CRP and BNP levels, only BNP predicted recurrence of AF (Odds Ratio 3.2, 95% CI: 1.7-6.0, p 0.001). Conclusion: Pre-ablation plasma BNP level is an independent predictor of AF recurrence after PVAI. CRP levels were not predictive of recurrence. BNP may be a more sensitive marker of atrial remodeling than CRP, atrial size or LV function. AB8-3