Abstract
INTRODUCTION: Aortopulmonary window (APW) is a rare congenital heart defect that causes left-to-right shunting and pulmonary overcirculation. Appropriate intervention prevents long-term complications. CASE PRESENTATION: We report a 3-year-old Iranian girl (weight ~ 14 kg, height ~ 95 cm) presenting with exertional dyspnea, systolic murmur, and bounding pulses. Echocardiography showed a 3 mm Type I APW with mild pulmonary hypertension. Pre-procedure catheterization revealed a mean pulmonary artery pressure (PAP) of 26 mmHg and a Qp/Qs ratio of 1.8. The defect was closed percutaneously using a 5 × 4 mm PFM coil. No pre-procedure CT scan was performed. Post-procedural evaluation demonstrated complete closure, mean PAP reduced to 18 mmHg, Qp/Qs normalized to 1.0, and no residual shunt. CONCLUSION: Transcatheter coil occlusion can be a safe and effective option for small APWs, offering favorable outcomes without the risks of open-heart surgery.