MEGF9 and pulmonary arterial hypertension: In the validation cohort, NID1 and CRTAC1 showed a significant dysregulation in PAH patients with early-decompensated RV and further in the late stage, while C1QTNF1 and MEGF9 were regulated only in late-stage PAH patients with decompensated RV (Fig. 8h–l).