Abstract
Aneurysms of the superior vena cava are rare vascular malformations of systemic veins. This report presents the case of a 27-year-old woman with an incidental finding of mediastinal shadow widening on the chest roentgenogram that was confirmed by computed tomographic angiography to be a superior vena cava saccular aneurysm >4 cm in diameter. Surgical resection was recommended on the basis of aneurysmal size and shape and was performed through median sternotomy by using cardiopulmonary bypass. The postoperative period was uneventful. During follow-up visits she remained asymptomatic. Saccular aneurysm surgery was recommended to prevent associated complications, including rupture, thrombosis, or venous obstruction.