Transaortic repair of a large aortopulmonary window with concomitant mitral valve repair in an infant with systemic pulmonary hypertension: a case report.

Background: Aortopulmonary window (APW) is a rare congenital cardiovascular defect characterized by an abnormal communication between the ascending aorta and the pulmonary artery despite the presence of separate semilunar valves. Large defects may result in pulmonary overcirculation, pulmonary hypertension, and heart failure during infancy. Case presentation: We report a 7-month-old boy admitted with a respiratory tract infection, in whom a continuous murmur prompted cardiac evaluation. Transthoracic echocardiography revealed a large APW measuring approximately 12 mm with exclusive left-to-right shunting, echocardiographically suspected systemic-level pulmonary arterial pressure, moderate-to-severe functional mitral regurgitation, mild aortic and tricuspid regurgitation, and left-sided chamber enlargement. A small muscular ventricular septal defect and a patent foramen ovale were also identified. Multislice computed tomography confirmed the aortopulmonary communication and demonstrated an adequate distance between the defect and the coronary arteries. Case discussion: After clinical stabilization, the patient underwent transaortic biologic patch closure through a median sternotomy. The aortic valve was inspected and preserved. Concomitant valve-preserving mitral repair was performed using a single commissural/coaptation stitch, while the small muscular ventricular septal defect was left untreated because it was hemodynamically insignificant. Postoperative echocardiography showed no residual APW shunt, reduced pulmonary pressure, and mild residual mitral regurgitation. Conclusion: Large APW in infancy can produce severe hemodynamic consequences. Individualized multimodality assessment and timely surgical repair can achieve favorable early outcomes. This case report is presented in accordance with the SCARE 2025 guidelines.