A hybrid wire guide is comprised of a distal segment of nitinol wire welded to a proximal segment of stainless steel wire. The stainless steel wire includes a flex transition segment that terminates at the weld, and defines a plurality of flexibility enhancing voids distributed in a pattern along a centerline so that a flexibility of the flex transition segment changes toward a match of a flexibility of the nitinol wire over a tracking segment that extends distally from the weld. The respective shapes of the flexibility enhancing voids change responsive to the flexure of the flex transition segment away from a straight configuration.
