Lipomatous hypertrophy presenting as superior vena cava syndrome.

We report a rare case of invasive lipomatous hypertrophy of the interatrial septum presenting as superior vena cava syndrome requiring surgical resection. Lipomatous hypertrophy of the interatrial septum is a common incidental finding and is thought to be a relatively benign condition. Classically, its appearance on cardiac computed tomography is primarily fatty with low attenuation, sharp margins and minimal enhancement, involving the interatrial septum with relative sparing of the fossa ovalis. In masses of unclear etiology or in rare, extensive cases resulting in cavity obstruction, such as ours, cardiac computed tomography provides complementary information to define tumor extent and characterize classic mass features facilitating diagnosis and management.