Strikingly, CT-proET-1 levels were strongly associated with markers of renal dysfunction (e.g., creatinine, r = 0.500, p < 0.001; cystatin C, r = 0.624, p < 0.001), cholestasis (e.g., bilirubin, r = 0.148, p = 0.031), impaired hepatic synthesis (e.g., albumin, r = −0.321, p = 0.001; pseudocholinesterase, r = −0.438, p < 0.001; prothrombin time, r = −0.220, p = 0.001) and cardiac failure (e.g., brain natriuretic peptide, r = 0.505, p < 0.001). This evidence concerns the gene NPPB and heart failure.