Apparatus and methods for advancing a wire guide (70) in either proximal or distal directions. The apparatus comprises a catheter (30) having proximal and distal (40) regions and a wire guide lumen (32) disposed therebetween. A cavity (60) is disposed in the distal region of the catheter, such that the cavity is in communication with a portion of the wire guide lumen. A wire guide is adapted to be disposed through the wire guide lumen and the cavity. At least one actuation mechanism (50) is disposed in the cavity and adapted to at least partially circumferentially surround the wire guide. The actuation mechanism may selectively engage the wire guide to effect movement of the wire guide in at least one direction with respect to the catheter.
