The present invention aims to provide a contrast agent-removal system and a method of operating the system for efficiently removing the contrast agent which is cause of the renal function impairment. The system of the present invention includes a blood suction catheter which can be placed into the coronary sinus, a column for removing a contrast agent from the drawn blood, a blood drawing circuit for directing the blood into the column, a blood pump for controlling an amount of the drawn blood, a blood return circuit for returning the blood from which the contrast agent is removed to a patients body and a device for measuring a blood suction pressure. In the method of operating the system, the blood is drawn with the blood suction catheter placed into the coronary sinus and the drawing blood is contacted with an adsorbent for adsorbing the contrast agent.
