NPPB and heart failure: In IRONMAN, a serum ferritin ≤ 30 μg/L was associated with features suggesting less severe heart failure and a better prognosis, including milder symptoms, lower NT-proBNP, and better renal function, therefore it is not surprising that, consistent with findings from previous observational studies of heart failure,6,9 ferritin was associated with a low rate for the primary endpoint whether or not patients were randomized to i.v. iron.