Objective:To investigate the application of transcatheter closure in patients with patent ductus arteriosus(PDA) with severe pulmonary arterial hypertension(SPH), and assess the medium and long-term results. Methods:Thirty seven patients with PDA underwent attempted transcatheter closure. On the basis of haemodynamic and clinical data obtained before and after attempted occlusion, the final PDA was carried out. The follow-up time was 1 week, 1,3, 6,12 months and every year after transcatheter closure. Results:The occlusion therapy was performed in 27 PDA. Systemic artery oxygen saturation before and after closure was (94.3±1.9)% and (96.2±1.4)%, respectively(P < 0.05). Systolic pulmonary arterial pressure (SPAP) decreased significantly from(90.1±17.2)mmHg to (45.1±10.9)mmHg (P < 0.05) and systolic arterial pressure increased significantly from (120.1±20.5)mmHg to (129.3±24.8)mmHg after closure(P < 0.05). The interventional occlusion was not carried out in 10 patients because of significant reduction of systemic artery oxygen saturation after six-minute walk test and no significant reduction of SPAP during the trial closure of PDA. In 27 patients with closure of PDA, SPAP was reduced to normal level in follow-up. Conclusion:Transcatheter closure is an effective treatment for patients with PDA associated with reversible SPH during the medium and long-term follow-up.