Changes of pulmonary artery pressure after transcatheter closure of patent ductus arteriosus complicated with severe pulmonary arterial hypertension

AIM:To evaluate the changes of pulmonary artery pressure (PAP) in patients with patent ductus arteriosus (PDA) and severe pulmonary arterial hypertension (PAH) after transcatheter device closure. METHODS: Transcather closure of PDA was performed in 111 patients with mean PAP (mPAP) >55 mmHg and pulmonary-to-systemic flow ratio (Qp/Qs) >1.5. PAP and aortic pressure were measured before and after device closure. Patients were followed clinically and with echocardiogram. RESULTS: All patients underwent successful transcatheter closure of PDA without major complications. PAP fell significantly (P<0.05) after device closure of PDA, but mPAP restored to normal level in only 37 patients (33.3%) immediately after PDA closure, and mild, moderate and severe PAH was, respectively, observed in 51, 14 and nine patients. The follow-up period was 1-8 (median 4) years. Twenty-four patients had PAH at 3 months after procedure but only 15 (13.5%) of them had PAH at 6 months, which was persistent during the whole follow up. Device closure resulted in drop in mPAP by (59±10)% in patients without PAH but only (24±14)% in patients with persistent post-procedural PAH (P<0.05). None of the patients with normal PAP and mild PAH but patients with severe PAH after PDA closure before device release had persistent post-procedural PAH. CONCLUSION: In patients with PDA and severe PAH, 13.5% will have persistent post-procedural PAH, although the pre-procedural Qp/Qs ratio is>1.5. Persistent post-procedural PAH will be inevitable in patients with severe PAH immediately after PDA closure and PAH will be persistent if the PAP is still higher than normal 6 months after procedure.