[Two cases of solitary peripheral pulmonary arterial aneurysm]

We report two very rare cases of solitary peripheral pulmonary arterial aneurysm. Case 1: An 83-year-old man treated for myocardial infarction died of multiple organ failure and hemoptysis. Autopsy disclosed rupture of a pulmonary arterial aneurysm 1.5 cm in diameter in the right A3. Case 2: A 75-year-old man was found to have a pulmonary arterial aneurysm, 3 cm in diameter of the right A1. Surgical treatment was not indicated, because of severe pulmonary emphysema. The aneurysms in these two cases were idiopathic: (1) there were no histologic findings that would implicate specific chronic inflammation. (2) the period from the occurrence of secondary pulmonary hypertension to hemoptysis was short, and there was no (3) history of trauma.