According to the results of the ROC analysis, miR-21, NT-proBNP, and galectin-3 might be good biomarkers to distinguish HF + DM (miR-21—sensitivity: 84.4%, specificity: 71.1%, p < 0.001; NT-proBNP—sensitivity: 100%, specificity: 100%, p < 0.001; galectin-3—sensitivity: 80.0%, specificity: 100%, p < 0.001) for miR-21, NT-proBNP, and galectin-3, respectively, from DM (Table 3). Here, NPPB is linked to hydrops fetalis.