An rotational atherectomy apparatus for abrading tissue, comprising: a flexible, elongated, rotatable drive shaft having a proximal end and a distal end opposite the proximal end; a nose cone operatively attached proximate the distal end of the drive shaft comprising a distal tapered section and a plurality of elongate, flexible members adjacent to the distal tapered section of the drive shaft, each member in the plurality being fixed at both a proximal end and a distal end opposite the proximal end; a proximal mount rotatable with the drive shaft and fixedly connected to the proximal ends of all the flexible members in the plurality; and a distal mount axially separated from the proximal mount and fixedly connected to the distal ends of all the flexible members in the plurality. When the axial separation of the proximal and distal mounts is reduced by pulling the distal tapered section proximally, each member in the plurality bows outward from the drive shaft and expands radially in an at least partially elliptical profile.