Superior vena cava syndrome secondary to saphenous venous graft aneurysm with right atrial fistula.

Mega-aneurysms of saphenous vein grafts (SVGs) to coronary arteries are rare complications of bypass surgery. We report the development of superior vena cava syndrome secondary to an SVG mega-aneurysm with concomitant fistulous communication to the right atrium. Successful treatment was achieved by coil embolization and chronic anticoagulation.