Azygos vein aneurysm--a case for elective resection.

Azygos vein aneurysm is a rare differential diagnosis for a posterior mediastinal mass lesion. It is often an incidental finding in a routine chest radiograph. Most azygos vein aneurysms are secondary to conditions causing elevated flow or pressure in the azygos system, like cardiac failure or cirrhosis of the liver. In this group of patients, once diagnosis is established, no treatment is required. Even in the idiopathic azygos vein aneurysms, where no primary cause can be identified, the recommendation so far has been to continue to observe rather than elective excision, since complications are unknown. We present the report of a 73 year old man who underwent excision of an azygos vein aneurysm, which contained a large, free floating thrombus. There has been another reported case of this complication as well [Gomez M-A, Delhommais A, Presicci PF, Besson M, Roger R, Alison D. Partial thrombosis of an idiopathic azygos aneurysm. Br J Radiol 2004;77:342-43].(1) In view of this we feel that it is safer to resect an idiopathic azygos vein aneurysm electively to prevent the possibility of pulmonary embolism.