Elevated BNP level in the acute setting is an important marker of congestive heart failure.14 Previous studies have reported that elevated BNP is an independent predictor of NOAF, which was confirmed in a recent large prospective study.5,15,16 While studies investigating the association of NOAF after MI and urea level are very limited, our study found that urea level significantly differed between MI patients who did and did not develop NOAF. This evidence concerns the gene NPPB and congestive heart failure.