An atherectomy device for removing stenosis materials from a vascular vessel is provided. The atherectomy device includes a flexible tubular member, a flexible drive means disposed within the tubular member, and a cutting assembly carried by the distal extremity of the tubular member. The cutting assembly includes a collection chamber which receives a cutting bit carried by the drive means. The cutting bit is rotated to remove materials from the stenosis and cause the removed materials to be withdrawn into the collection chamber as the bit is advanced. A second embodiment of the atherectomy device includes an anchor member coaxially mounted within a tubular cutting blade at the distal end of the catheter. The anchor member is first advanced into a region of stenosis where it becomes embedded, and the tubular blade is subsequently advanced over the anchor member to sever the stenosis. The tubular blade and anchor member may be retracted within the catheter and thus used to withdraw the several material from the blood vessel.