An introducer (10) includes a dilator received in its lumen and including a dilation end extending distally beyond a distal end of the sheath. The introducer sheath (10) includes a flat wire reinforcement (24) having a hollow cylindrical shape sandwiched between an inner PTFE tube (25) and an outer nylon tube (26). The outer tube includes a distal segment (27) extending distally beyond the PTFE tube (25), which extends distally beyond the flat wire reinforcement (24). A withdrawal support wire (33) has a distal end (34) attached to a distal end turn of the reinforcement (24) and extends in parallel with a longitudinal axis between an outer surface of the nylon tube (25) and an inner surface of the PTFE tube (26). The withdrawal support wire (24) is configured to be in tension when the sheath (10) is placed in tension to inhibit distal stretch separation breakage.
