B-type natriuretic peptide level after sinus rhythm restoration in patients with persistent atrial fibrillation - clinical significance.

Background: Persistent atrial fibrillation (AF) leads to electrical, structural and neurohormonal remodelling of the atria, including increased plasma B-type natriuretic peptide (BNP) level.

Aim: To assess the clinical value of plasma BNP or NT-proBNP concentrations in patients with persistent AF measured before and after sinus rhythm restoration following direct-current cardioversion.

Methods: The study group consisted of 43 patients with persistent AF who underwent successful electrical cardioversion. The mean AF duration was 12.3 weeks. Patients in the study group had no symptoms of heart failure and they had preserved left ventricular systolic function. Blood samples were collected twice: 24 hours before and 24 hours after electrical cardioversion. Logistic regression analysis was used to assess the predictive value of BNP and NT-proBNP levels.

Results: Baseline NT-proBNP and BNP levels were increased in patients with persistent AF (290.9 +/- 257.2 pg/mL and 148.4 +/- 111.4 pg/mL, respectively) compared to a matched control group without AF (47.8 +/- 80.6 pg/mL; p = 0.0001 and 74.9 +/- 81.7 pg/mL; p = 0.01). Plasma BNP level decreased 24 hours after cardioversion (from 148.4 +/- 111.4 to 106.4 +/- 74.7 pg/mL; p = 0.0045) whereas NT-proBNP level did not (from 290.9 +/- 257.2 to 262.7 +/- 185.6 pg/mL; NS). During an 18-month follow-up period, 21 (49%) patients remained in sinus rhythm. Neither baseline plasma BNP nor NT-proBNP level predicted sinus rhythm maintenance.

Conclusions: NT-proBNP and BNP plasma levels are increased in patients with persistent AF. Conversion to sinus rhythm is associated with a significant decrease in plasma BNP but not NT-proBNP level. Baseline BNP and NT-proBNP levels do not predict long-term sinus rhythm maintenance.