Serum Amyloid A and C-Reactive Protein Independently Predict the Recurrences of Atrial Fibrillation After Cardioversion in Patients With Preserved Left Ventricular Function

Background: Subclinical inflammation and atrial stretch have been recognized as important contributors to atrial fibrillation (AF) onset and perpetuation. The aim of the study was to compare the predictive role of serum inflammatory markers (serum amyloid A [SAA], and C-reactive protein [CRP]) and N-terminal pro brain natriuretic peptide (NT-proBNP) an indice of atrial strain in relation to subacute arrhythmic recurrence rate in patients with persistent AF and normal left ventricular ejection fraction (LVEF). Methods: We studied 57 patients with a mean LVEF of 58.7 +/- 6%. NT-proBNP, SAA and CRP levels were determined few hours before electrical cardioversion and 3 weeks after cardioversion. Results: Subacute AF recurrences were documented in 19 (33 %) patients. Whereas NT-proBNP levels did not predict arrhythmic outcome, higher SAA (> 6.16-6.19 mg/L) and CRP levels (> 2.99-3.10 mg/L) were significantly associated with AF recurrences (odds ratio [OR], 5.39; 95% confidence interval [CI], 1.59-18.26; P = 0.007 and OR, 14.93; 95% CI, 3.90-57.19; P < 0.001). Both SAA (OR, 18.29; 95% CI, 2.07-161.46; P = 0.009) and high sensitivity CRP (OR, 42.03; 95% CI, 4.83-365.45; P = 0.001) through the multivariate logistic regression analysis show an independent role in predicting the AF recurrence with a sensitivity of 100% (38/38) and a specificity of 52.6% (10/19). Conclusions: The present study demonstrates that in patients with persistent AF and preserved LVEF, SAA and CRP levels are independent predictors of AF subacute recurrence rate, whereas NT-proBNP, not associated with arrhythmic outcome, reflects the hemodynamic alterations secondary to arrhythmia presence. The simultaneous determination of SAA and high sensitivity CRP has a very high sensitivity (100%) in predicting the AF recurrence.