Although vein graft aneurysms have been described to be atherosclerotic in nature, it has been hypothesized that vein graft aneurysms may be a part of a systemic dilating process. In the case reported here, histopathologic examination of vein graft aneurysms demonstrates aneurysmal degeneration with no atherosclerotic changes and do support the hypothesis that vein graft aneurysms may be a manifestation of a systemic dilating process.