The use of long-term right atrial access catheters is increasing due to their value as aids in the administration of chemotherapy and hyperalimentation. A rare complication of catheter use is subclavian vein thrombosis. Suspicion of subclavian venous thrombosis based on clinical findings should be confirmed by venography. Therapy should be individualized, but may include antibiotics, catheter removal, thrombolytics, and anticoagulants. Resolution of symptoms is the usual outcome, but this may be influenced by other compounding factors.