Of the 6,227 consecutive patients hospitalized in CICUs, 3,774 were excluded for the following reasons (younger than 18 years in 16 patients; absence of SCr, NT-proBNP, or LVEF data in 3,364 patients; stage 5 CKD in 377 patients; length of stay in CICUs < 24 h in 32 patients; and kidney transplantation in 2 patients). Here, NPPB is linked to chronic kidney disease.