PADN: Contrast pulmonary artery (PA) angiography will be performed to localize the pulmonary artery bifurcation level and calculate the PA diameter. Once the anatomy deemed acceptable, the radiofrequency ablation catheter will be introduced into ostium of the left PA and the distal bifurcation area of the main PA. The catheter will be manoeuvred within the PA to allow energy delivery in a circumferential manner to ensure that the electrodes are tightly in contact with the endovascular surface. About three ablations at 45-55 # for 120 seconds each will be performed in ostium of the left PA and the distal bifurcation area of the main PA. For non-atrial fibrillation patients, dual antiplatelet therapy for 1 month after PADN is recommended. Patients with atrial fibrillation should continue new oral anticoagulants and patients who underwent metal valve replacement should continued oral warfarin anticoagulation according to guidelines, which could determined by the physician.

Clinical worsening events defined as any of the following during the study period:

1. PAH-related rehospitalization.
2. Addition of PAH-targeted therapies (increased types/dose of PAH-targeted drugs or diuretics).
3. ≥10% or ≥30-meter reduction in 6-Minute Walk Distance (6MWD) from baseline.
4. Atrial septostomy.
5. Need for lung transplantation.
6. Cardiovascular death.