Catheter wire guide with movable mandril

Claim 1

A wire guide having a flexible distal tip and adapted for guiding a catheter within a body blood vessel, comprising: a helically wound wire including coils defining a longitudinal opening; a mandril including distal and proximal ends and having a distal portion and a proximal portion, said mandril being slidably received within said longitudinal opening of said wire, whereby said distal end of said mandril is longitudinally movable therein relative to said wire for varying the flexibility of said distal tip of said wire guide, said distal portion being tapered inwardly towards the distal end of said mandril thereby causing said wire guide flexibility to progressively increase along said taper, said mandril further including an enlarged bulb at said distal end, whereby said bulb permits said mandril to be advanced relative to the longitudinal opening of said helically wound wire with the flexible distal tip of said wire guide flexed without said mandril protruding through the coils of said helically wound wire; and, a means, including a coating of lubricating material, for facilitating smooth movement of said mandril within said opening of said helically wound wire.