Aneurysmal change in an internal mammary artery–pulmonary artery fistula

We treated a rare case of aneurysm of the internal mammary artery–pulmonary artery fistula in a 32-year-old woman with unrepaired pulmonary atresia and ventricular septal defect. This aneurysm communicated with the pulmonary artery system through an aortopulmonary collateral. Aneurysmectomy was successful.