NPPB and heart failure: In recent years, numerous biological markers have been progressively studied and applied in ADHF, such as B-type natriuretic peptide (BNP), N-terminal pro-BNP (NT-proBNP), mid-regional pro-atrial natriuretic peptide (MR-proANP), and cystatin C. Among these, NT-proBNP is commonly used as a gold standard for diagnosing heart failure.