Coated wire guide and method of making same

Abstract

In at least one embodiment, a method for making a wire guide is provided. The method comprises applying a polymer coating to a proximal section of a FP coated core wire having a FP coating disposed thereon such that the polymer coating overlays at least a portion of the FP coating. The polymer coating is applied to a distal section of the FP coated core wire having an exposed metal portion such that the polymer coating overlays at least a portion of the exposed metal portion. The polymer coating is removed from the proximal portion of the FP coated core wire to form the wire guide having a proximal portion with the FP coating and a distal portion with the polymer coating.

1 . A method for making a wire guide comprising:
 providing a core wire having a fluoropolymer (FP) coating disposed thereon defining a FP coated core wire, wherein a distal section of the FP coated core wire comprises an exposed metal portion;   applying a polymer coating to a proximal section of the FP coated core wire such that the polymer coating overlays at least a portion of the FP coating;   applying the polymer coating to the distal section of the FP coated core wire such that the polymer coating overlays at least a portion of the exposed metal portion; and   removing the polymer coating from the proximal section of the FP coated core wire to form the wire guide having a proximal portion with the FP coating and a distal portion with the polymer coating.   
     
     
         2 . The method according to  claim 1  wherein the step of applying the polymer coating to the proximal section includes extruding the polymer coating over the FP coating, and the step of applying the polymer coating to the distal section includes extruding the polymer coating over the exposed metal portion. 
     
     
         3 . The method according to  claim 1  wherein the polymer coating comprises polyurethanes, polyesters, polyamides, polyethylene, polystyrene, polyether block amides or a mixture thereof, and the FP coating comprises polytetrafluoroethylene (PTFE), fluorinated ethylene-propylene (FEP), polyethylenetetrafluoroethylene (ETFE), perfluoroalkoxy polymer (PFA), polyvinylfluoride (PVF), polyethylenechlorotrifluoroethylene (ECTFE), polyvinylidene fluoride (PVDF) or a mixture thereof. 
     
     
         4 . The method according to  claim 1  wherein the step of removing the polymer coating includes stripping the polymer coating from the proximal section such that the polymer coating remains on the distal section forming an edge adjacent to the FP coating. 
     
     
         5 . The method according to  claim 1  wherein the FP coated core wire includes metal material covered by the FP coating, and the method further comprises removing material from the distal section of the FP coated core wire including removing the FP coating to provide the exposed metal portion. 
     
     
         6 . The method according to  claim 5  wherein the step of removing the material includes machining the distal section of the FP coated core wire to form a distally tapered end portion. 
     
     
         7 . The method according to  claim 5  further comprising applying hydrophilic coating to the distal section over the polymer coating. 
     
     
         8 . The method according to  claim 7  wherein the FP coating and the hydrophilic coating form respectively a proximal exterior surface and a distal exterior surface of the wire guide, and wherein a coefficient of friction of the distal exterior surface is relatively lower than a coefficient of friction of the proximal exterior surface. 
     
     
         9 . The method according to  claim 7  wherein the polymer coating is affixed to both the metal material and the hydrophilic coating, providing adhesion of the hydrophilic coating to the distal section of the FP coated core wire. 
     
     
         10 . The method according to  claim 7  wherein the hydrophilic coating comprises polyvinylpyrrolidones, polyethylene oxides, polyacrylates or a mixture thereof. 
     
     
         11 . A wire guide comprising:
 a core wire having a proximal section extending to a distal section, the proximal section having a fluoropolymer (FP) coating disposed thereon and the distal section having a polymer coating disposed thereon, the polymer coating having an edge that is adjacent to the FP coating and is defined by removal of the polymer coating from the proximal section of the core wire.   
     
     
         12 . The wire guide according to  claim 11  wherein the distal section of the core wire has a distally tapered end portion formed of metal material, and the polymer coating covers the distally tapered end portion. 
     
     
         13 . The wire guide according to  claim 12  wherein the distal section of the core wire has a longitudinal axis, and the polymer coating disposed about the distal section of the core wire has an outer diameter defined by extrusion of a substantially circular cross-section along a length of the longitudinal axis. 
     
     
         14 . The wire guide according to  claim 12  wherein the distal section of the core wire has a hydrophilic coating disposed thereon covering the polymer coating. 
     
     
         15 . The wire guide according to  claim 14  wherein the FP coating and the hydrophilic coating form respectively a proximal exterior surface and a distal exterior surface of the wire guide, and wherein a coefficient of friction of the distal exterior surface is relatively lower than a coefficient of friction of the proximal exterior surface. 
     
     
         16 . The wire guide according to  claim 14  wherein the polymer coating is affixed to both the metal material and the hydrophilic coating, providing adhesion of the hydrophilic coating to the distal section of the core wire. 
     
     
         17 . A catheter kit comprising:
 a guide catheter for insertion into a patient;   a wire guide for providing the guide catheter a path during insertion into the patient, the wire guide including a core wire having a proximal section extending to a distal section, the proximal section having a fluoropolymer (FP) coating disposed thereon and the distal section having a polymer coating disposed thereon, the polymer coating having an edge that is adjacent to the FP coating and is defined by removal of the polymer coating from the proximal section of the core wire; and   a needle for introducing the wire guide into the patient.   
     
     
         18 . The catheter kit according to  claim 17  further comprising a microcatheter configured to be positioned through the guide catheter for positioning in the patient. 
     
     
         19 . The catheter kit according to  claim 17  wherein the distal section of the core wire has a distally tapered end portion formed of metal material, and the polymer coating covers the distally tapered end portion. 
     
     
         20 . The catheter kit according to  claim 19  wherein the distal section of the core wire has a hydrophilic coating disposed thereon covering the polymer coating, the polymer coating is affixed to both the metal material and the hydrophilic coating to provide adhesion of the hydrophilic coating to the distal section of the core wire, the FP coating and the hydrophilic coating form respectively a proximal exterior surface and a distal exterior surface of the wire guide, and wherein a coefficient of friction of the distal exterior surface is relatively lower than a coefficient of friction of the proximal exterior surface.