Aim To evaluate the immediate and follow-up results of transcatheter closure of large PDAs with severe pulmonary arterial hypertension (PAH) in adults.

Method After a complete haemodynamic evaluation differentiating from the reversibility of severe PAH, transcatheter closure of PDA was performed. Patients were followed up clinically and echocardiographically at 24 h, 1 month, 3 months, 6 months, 12 months and 24 months after occlusion.

Results 38 patients had successful occlusion, PAP, LVEF and FS significantly decreased immediately after occlusion (92.5±23.1 mm Hg vs 47.2±15.7 mm Hg, p<0.01; 66.5±9.0 vs 52.2±10.73, p<0.05 and 6.3±8.8 vs 28.9±9.1, p<0.05, respectively). At 1 month after PDA closure, the signs and symptoms had improved markedly in all 38 patients, and PDAs were completely closed and remained closed during the follow up. 25 patients having different degrees of dyspnoea were treated with ACEI and/or digoxin after occlusion. After 1 to 3 months of peroral drug therapy, their exercise tolerance had improved from NYHA class III-IV to NYHA class I. During follow up, no latent arrhythmias were found, the LAD, LVEDD, LVESD, LVMI and PASP decreased significantly (p<0.05), and FS and LVEF recovered compared to the immediate postclosure state. However, FS and LVEF remained low compared to the preclosure state.

Conclusion Transcatheter closure of large PDA with severe PAH is feasible, effective, and safe in the adults. Significant LV systolic changes may occur after closure of large PDA, and LV function usually recovers within a few months. Further study should be performed.