NPPB and carcinoid heart disease: It has been shown that cardiac neurohormone N-terminal pro-brain natriuretic peptide (NT-pro-BNP) has both diagnostic significance with a sensitivity of 92% and a specificity of 91% for a cut-off level of 260 pg/mL (31 pmol/L) and prognostic significance for carcinoid heart disease [47,48].