NPPB and heart failure: The mean values for the specificity of BNP/NTproBNP in the diagnosis of heart failure are 80–85% and the mean sensibility is 75% (with NTproBNP being a stronger marker of heart failure), but there was a great variation of cut-off values between these trials [1,18,20,21,36,37,38,42,43,44,48,49,50,51,52,53,54,55,56,57].