| abstract |
An improved expandable removal element (16) for an atherectomy device wherein the expandable removal element (16) is movable between an expanded position and a contracted position. In one embodiment of the present invention, a single drive shaft (92) is operatively connected to the distal end of the expandable material removal element (16) for rotating the removal element (16). A catheter (178) may surround a portion of the drive shaft (92). The catheter (178) is shiftable with respect to the drive shaft (92) for moving the material removal element between the expanded position and the contracted position. In another embodiment of the present invention, dual coaxial drive shafts are employed. The inner drive shaft (312) and the outer drive (314) are shiftable with respect to one another for moving the removal element (252) between the expanded position and the contracted position. The present invention also describes several embodiments for an improved removal element (252). |