Superior vena caval aneurysm.

Venous aneurysms arising from the mediastinal systemic veins are rare. There are only 27 reported cases of such aneurysms. Majority arise from the superior vena cava. We are reporting a saccular aneurysm of superior vena cava in a 58-year-old male. The chest radiogram suggested superior mediastinal mass and the computed tomogram was suggestive of aortic arch aneurysm. Aortography and venography confirmed the diagnosis as saccular aneurysm arising from the superior vena cava. A 7 cm saccular aneurysm arising from the distal half of superior vena cava was resected through median sternotomy. The surgery was done to prevent pulmonary thrombo-embolism.