NPPB and hydrops fetalis: A single-center study found that in acute decompensated HF, BNP levels were lower in Fontan patients compared to non-Fontan patients, 390.9 (±378.7) pg/mL vs 1,245.6 (±1,160.7) pg/mL, respectively, but higher in Fontan patients with systemic ventricular systolic or diastolic dysfunction compared to those with normal systemic ventricular function, 833.6 (±1,547.2) pg/mL vs 138.6 (±134.0) pg/mL.26