Preformed wire guide

Abstract

A preformed anchoring wire guide (,) for medical procedures such as renal angioplasty. The wire guide (,) is comprised of a superelastic memory alloy mandril (,), such as a nickel-titanium alloy, and includes a preformed bend (,) having an angle (,) with respect to the longitudinal axis (,) that corresponds with the takeoff angle of the renal artery (,) relative to the aorta (,). This preformed bend (,) allows easier access to the ostium (,) of the renal artery (,) and allows the distal portion (,) of the wire guide to anchor within the artery (,) and resist dislodgement and deformation, thereby improving trackability of a balloon angioplasty catheter (,), reducing the need for a guiding catheter, and reducing the likelihood of vessel damage or thrombus shear due to forces that are normally exerted against the wall of the vessel (,) by a standard wire guide. The wire guide has a tapered distal portion (,) over which a spring coil wire (,) is attached to provide radiopacity and safety to the vasculature. The distal portion (,) of the wire guide is flexible and is further made atraumatic by the addition of a hook-shaped or “J” tip (,). Additionally, the nickel-titanium alloy mandril is cold-worked in its austenitic phase at preformed bend (,) by overstressing the wire in a fixture, thereby shifting at least part of the crystalline structure to martensite within the region of the preformed bend (,).