NPPB and atrial fibrillation: In the multivariate logistic regression, adjusted by persistent AF, left atrial diameter and pre-procedural plasma NT-proBNP level, not only pre-procedural titer of serum anti-M2-R (odds ratio: 2.339; 95% confidence interval: 1.509-3.626; p < 0.001) but also the presence of anti-M2-R (odds ratio: 4.701; 95% confidence interval: 1.590-13.894; p = 0.005) was an independent predictor for the recurrence of AF at one year after RFCA.