[Idiopathic Pulmonary Artery Aneurysm].

Pulmonary artery aneurysm (PAA) is usually associated with congenital heart disease, pulmonary artery hypertension, and connective tissue abnormalities, but idiopathic PAA is a rare clinical entity. We experienced a surgical case of idiopathic PAA measuring 60 mm in diameter. A 72-year-old man had been admitted to a nearby hospital 5 years before because of an abnormal shadow on chest X-ray, and was diagnosed with an idiopathic PAA measuring 37 mm in diameter. The PAA gradually expanded during follow-up and surgery was scheduled. Aneurysmal resection and reconstruction with a 24 mm expanded polytetrafluoroethylene graft were performed. The postoperative course was uneventful and the patient was discharged on the 11th postoperative day.