MMP1 and hydrops fetalis: As shown in Figure 1A, the frequency of patients exhibiting the combination of high PICP (≥ median value = 70.4 ng/mL) and low CITP:MMP-1 ratio (≤ median value = 3.58) was higher (p < 0.001) in the HFpEF group (43.6%) than in the non-HF group (16.4%).