Roughly, CHF appears to be highly unlikely below a BNP plasma concentration of 100 pg/ml, or a NT-proBNP below 500 pg/mL, and CHF appears to be likely when plasma concentration of BNP is higher than 500 pg/ml, or NT-proBNP is greater 2000 pg/mL (Fig. 4). This evidence concerns the gene NPPB and congestive heart failure.