Aortopulmonary Window: Classification, Associated Cardiac Anomalies, Treatment Options, and Clinical Outcome

Objective: Aortopulmonary window (APW) is an uncommon congenital cardiac abnormality marked by a septation defect between the ascending aorta and pulmonary artery. This study aimed to define the clinical characteristics, diagnostic features, treatment strategies, and follow-up outcomes of pediatric patients diagnosed with APW.
Material and Methods: We retrospectively reviewed children diagnosed with APW from 2010 to 2023. Morphological APW typing of our patients was based on the classification that is settled by the Society of Thoracic Surgeons (STS) Congenital Heart Surgery Database Committee. The patients’ demographic data, symptoms at admission, transthoracic echocardiography, cardiac computed tomography, management modalities, and follow-up data were evaluated.
Results: Twenty-five children were diagnosed with APW over the study period. Thirteen patients were male (52%), and the median age at presentation of the patients was three months (8 days-7.5 years). Two patients were diagnosed with coronary fistula by echocardiography at the first admission and were diagnosed with APW after catheterization. APW was detected in one patient while being operated on for large ventricular septal defect. According to the STS classification, 32% (n=8) of the patients were type III, 32% (n=8) were type I, 16% (n=4) were intermediate type, 12% (n=3) were type II, and 4% (n=1) were APW with aortic interruption. Associated cardiovascular malformations were in 76% (n=19) of the patients. Fifteen patients (60%) underwent surgery. Transcatheter closure of APW was performed in four patients (16%).
Conclusion: Detection of the APW requires careful and systematic investigation. Transcatheter closure can be performed in selected cases where the defect is suitable. Although rare, this defect, which can cause severe left-right shunting, should be kept in mind as a cause of pulmonary hypertension and unexplained cardiac dilation and should be investigated in patients whose cause cannot be determined.