A method and apparatus for uncoupling a wire guide from and elongate medical device comprising a catheter shaft having a wire guide lumen extending there through, wherein the material surrounding the wire guide lumen is selected or adapted to facilitate splittability for removal of the wire guide. The catheter shaft includes a wire guide port having a stress riser, the stress riser being configured to reduce the force necessary to rupture or split the portion of the shaft wall adjacent to the wire guide port. In a preferred embodiment, the catheter shaft is coextruded and comprises a plurality of materials. The portion of the shaft adjacent the wire guide lumen is formed from a material is selected or adapted to facilitate splittability as compared to the remaining shaft materials.
