A motorized rotary catheter, for breaking down and aspirating an obstruction from within a bodily vessel comprising a flexible tube containing a motor-driven, flexible, hollow shaft that is rotatable and slidable over a guidewire a distal portion of the shaft is made of a closely wound spiraled wire and a distal portion of that spiraled wire is extendable out of a distal end of the tube a bit affixed to a distal end of the spiraled wire forms therewith a tip that has first and second opposing sides for impacting and breaking down the obstruction as the shaft rotates the tip also has a base and an opposing crown that is offset away from a longitudinal axis of the shaft further than the base is, enlarging the area that the tip sweeps as it rotates a distance between the sides being smaller than a distance between the crown and the base, enhancing the ability of the tip to pass through tight spots along the vessel as the tip rotates and the crown atraumatically slides against a wall of the vessel it displaces the distal end of the tip away from the wall to prevent the distal end of the tip from starting to tunnel through the obstruction too close to the wall.
