NT-proBNP levels (mean ± SD) in the non-HF, HFrEF, HFmrEF, and HFpEF groups were 134.2 ± 66.13, 9809 ± 9406, 7073 ± 6360, and 7489 ± 8975 ng/L, respectively, showing a significant difference between the HF groups and the non-HF control group. Here, NPPB is linked to hydrops fetalis.