NPPB and hydrops fetalis: The performance of serum NT-proBNP level in discriminating between patients with advanced HF and those with mild HF was as follows: AUC = 0.73 (95% CI: 0.63–0.82), optimal cut-off value = 2379 pg/mL, Se = 52.0% (95%CI: 37.42–66.34%), Sp = 88.06% (95%CI: 77.82–94.70%), PPV = 76.47% (95% CI: 60.73–85.53%) and NPV = 71.08% (95% CI: 57.57–85.63%).