We report the unusual presentation of a saphenous vein graft aneurysm in a 72-year-old man who had undergone coronary artery bypass surgery 15 years prior to admission. The patient presented with a large mass on the anterior wall of the right ventricle and chest discomfort; initially believed to be a cardiac tumor. The patient underwent reoperative coronary surgery with excision of the saphenous vein graft aneurysm, followed by an uneventful postoperative course. Aortocoronary saphenous vein graft aneurysms are rare and their presentation may be mistaken for pulmonary or chest wall lesions. Complications include rupture, and therefore require attentive diagnosis and surgical therapy.