Whereas in patients with LsPe AF (n = 27) we found significantly higher preoperative plasma ANP levels in those individuals, who had converted to SR after 6 months, as compared to those who remained in AF (median 9.95 [7.53-14.02] vs 6.86 [5.68-8.06] nmol/l, p = 0.009) (Figure 4). Here, NPPA is linked to atrial fibrillation.