Highly flexible, telescoping atherectomy device

A highly flexible, telescoping atherectomy device, comprising:

• a distal end, a proximal end, a long axis, and a guidewire lumen passing through the device in the direction of the long axis;
• a flexible sheath having an outer diameter and a sheath lumen;
• a cutter having a proximal end, a distal end, and a body with a plurality of helical flutes, a point at the distal end having a plurality of cutting lips, a cutter lumen, and a cleared diameter;
• a drive assembly having
• an unsheathed and flexible driveshaft including an axis, a proximal end, a distal end, an outer surface, and a driveshaft lumen, the distal end of the unsheathed and flexible drive shaft having a fixed connection with the cutter, wherein the unsheathed and flexible drive shaft is rotatably translational within the lumen of the flexible sheath to drive the cutter;
• and,
• a reversibly-expandable, lateral pushing member at the distal end of the flexible sheath, the lateral pushing member having a proximal end, a distal end, a collapsed state, and an expanded state, the proximal end having a connector assembly with the flexible sheath, and the distal end having an operable connection with the cutter;
• wherein,
• the cleared diameter of the cutter is greater than the outer diameter of the flexible drive shaft;
• the guidewire lumen includes the cutter lumen and the driveshaft lumen;
• and
• the unsheathed and flexible drive shaft is longer than the flexible sheath to enable a reversible telescoping of the unsheathed and flexible drive shaft from the distal end of the flexible sheath to increase the flexibility of the atherectomy device when directing the cutter to a target site for the cutter;
• the connector assembly with the flexible sheath and the operable connection with the cutter are each configured to receive an axial force (i) applied along the axis of the flexible drive shaft from the cutter to the flexible sheath and (ii) transferred through the lateral pushing member during the collapse and the expansion of the lateral pushing member with the reversible telescoping of the flexible drive shaft from the flexible sheath;
• and,
• the connector assembly with the cutter is configured as a rotatably translatable connection to facilitate a rotation of the cutter and the flexible drive shaft without rotating the lateral pushing member during operation of the atherectomy device.