Clinical diagnostic value of circulating serum miR-509-3p in pulmonary arterial hypertension with congenital heart disease

OBJECTIVE: Most pulmonary arterial hypertension (PAH) biomarkers are used for risk stratification and prognosis prediction. We aimed to evaluate the diagnostic value of circulating serum miR-509-3p in PAH with congenital heart disease. METHODS: Preoperative blood samples were collected from patients who were diagnosed as having PAH and had to receive right ventricular catheterization. According to right ventricular catheterization results, these patients were divided into a control group with normal mean pulmonary artery pressure (mPAP < 20 mmHg) and a PAH group (mPAP ≥ 25 mmHg). The expression of serum miR-509-3p was detected by real-time quantitative PCR. The receiver operating characteristic curve was plotted. A dichotomous logistic regression model was also established. RESULTS: The expression level of circulating serum miR-509-3p in the PAH group was significantly lower than that of the control group. Based on the relative expression of miR-509-3p in serum, the area under the curve (AUC) for single-factor diagnosis of PAH was 0.694 (95% confidence interval [CI]: 0.555-0.883, P = 0.01), which was approximately 0.81 (AUC of noninvasive screening by echocardiography). When the relative expression of miR-509-3p was 0.79, the sensitivity and specificity were 80% and 60%, respectively. Based on the established model, AUC of serum miR-509-3p combined with echocardiography was 0.844, thus indicating a high diagnostic value. Compared with two individual indices, the combination further enhanced the diagnostic efficiency. CONCLUSIONS: The expression of miR-509-3p decreased in the serum of patients with PAH along with congenital heart disease. The diagnostic value of circulating serum miR-509-3p in PAH was close to that obtained by echocardiography. Combining the two indices further increased the diagnostic efficiency of PAH.