An attachment mechanism (125, 225, 325, 425, 525, 625) and method for attaching or coupling a guide wire (130, 230, 330,430, 530, 630) to a catheter for re - canalization or opening a passage through an occlusion in a blood vessel is provided. The attachment mechanism generates friction forces against the guide wire to couple the guide wire to a catheter, which design permits a greater force to be used on the guide wire during a re - canalization procedure. The invention also encompasses use of the attachment mechanism in conjunction with active catheters, which have vibration - generating means to oscillate the distal end of the catheter or a component in the distal end of the catheter, to add vibration motion, preferably axial vibration motion, to the increased force that may be applied to the guide wire for purposes of penetrating an occlusion. The methods of the invention relate to methods of attaching the guide wire to the catheter and methods of treating a vessel having a partial or total occlusion.