NPPB and acute kidney injury: Current studies indicate that the causes of AKI after AMI are very complex and may involve many mechanisms, such as ischemia-reperfusion injury, inflammation, oxidative stress, nephrotoxicity, etc4; the prediction of post-AMI AKI is being widely carried out, such as the combined detection of red blood cell distribution width (RDW) and N-terminal brain natriuretic peptide (NT-proBNP)5.