| 摘要 |
<p>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. 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 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 removal element of the present invention comprised a plurality of braided wires having an abrasive disposed thereon. A plurality of individual wires within each 'braid' is provided to increase the abrasive surface area of the removal element. Another embodiment of the present invention is to provide a braid pattern wherein each single primary braid wire within the braid pattern is individually radially wrapped with a second 'wrapping' wire (342). The 'wrapping' wire (342), which may be coated with an abrasive (344), primarily performs the removal function.</p> |
