Spearman test was further implemented to analyze the correlations of serum BNP, PTX3, and VEGF levels and the severity of PAH, and the findings signified that that serum BNP, PTX3, and VEGF levels were positively correlated with the severity of PAH (mild, moderate, and mild) in APE‐PAH patients (r = 0.377, 0.488, 0.575, all p < .05; Table 7). The gene discussed is PTX3; the disease is pulmonary arterial hypertension.