Angle–Torque Transmission Characteristics of Ti–Ta–Sn Alloy Guidewire

Abstract

As a simulated blood vessel circuit, a silicone tube was introduced into the groove of a circuit constituted by a curved line of 90° combined with a radius of curvature of R20 mm. The rotational angle trackability and torque transmission performance in this simulated blood vessel circuit were compared for core material bases of stainless steel and Ni–Ti alloy commercial guidewires and of a Ti–Ta–Sn alloy. According to the load–deflection curve, on protruding by 2 mm, the highest load was measured for stainless steel; however, plastic deformation was observed after unloading. The Ni–Ti alloy exhibited higher load values than the Ti–Ta–Sn alloy, the latter showing a load as small as 2.2 N; however, after unloading, the displacement was fully recovered in both cases. The best and worst rotational angle trackabilities were observed for Ti–Ta–Sn and Ni–Ti alloys, respectively. The proximal tip side torque was large in the stainless steel and Ni–Ti alloy, whereas the Ti–Ta–Sn alloy exhibited a small value. The distal tip side torque was the largest in stainless steel, whereas Ni–Ti and Ti–Ta–Sn alloys showed almost similar values. Comparing the results of torque loss, Ni–Ti and Ti–Ta–Sn alloys exhibited the largest and smallest torque losses, respectively. The results indicated that the rotational angle trackability of the Ti–Ta–Sn alloy is higher than that of a commercially available guidewire core, while showing the smallest torque.