NPPA and atrial fibrillation: N-terminal pro-BNP (NT-proBNP) (269 pg/mL, reference range: <126 pg/mL) and BNP (43.3 pg/mL, reference range: <18.4pg/mL) levels were elevated, whereas the increase in ANP level was marginal (46.1 pg/mL, reference range: <43 pg/mL), suggesting impaired ANP secretion due to long-standing AF.