APOA1 and hydrops fetalis: Four proteins were significantly differentially expressed between non‐HF and the specific subtypes of HF (HFrEF and HFpEF); Leucine‐rich‐alpha‐2‐glycoprotein (LRG1, P < 0.001), zinc‐alpha‐2‐glycoprotein (P = 0.005), serum paraoxanse/arylesterase (P = 0.013), and APOA1 (P = 0.038).