Whereas, in the AF control group without ablation plasma ANP levels were higher in comparison to the SR control group, preoperatively (median 7.24 vs 3.78 nmol/l, p = 0.03) and at 6 months follow-up (median 7.23 vs 4.86 nmol/l, p = 0.01). This evidence concerns the gene NPPA and atrial fibrillation.