Implantable medical electrical lead conductors and construction methods

Abstract

A coiled continuous conductor wire of an implantable medical electrical lead includes a first, electrode length and a second, insulated length, wherein the insulated length of the wire has a radial cross-section defined by a round profile, while the electrode length of the wire has a radial cross-section defined by a flattened profile, a long axis edge of which defines an outer diameter surface of the electrode length. The radial cross-section profile, along the electrode length of wire, is preferably flattened after an entire length of the wire has been coiled.

1 . An implantable medical electrical lead comprising a continuous conductor wire wound in a coil, the conductor wire comprising an insulated length, extending distally from a connector terminal of the lead, and an electrode length, extending distally from the insulated length, and wherein the improvement comprises: the insulated length of the wire having a radial cross-section defined by a round profile, while the electrode length of the wire having a radial cross-section defined by a flattened profile, the flattened profile having a long axis and a short axis, and an outer diameter surface of the electrode length being defined by a long axis edge of the flattened profile. 
     
     
         2 . The lead of  claim 1 , wherein the conductor wire is formed of Ta, and the electrode length of the wire includes a native pentoxide coating extending over a portion of the outer diameter surface thereof. 
     
     
         3 . The lead of  claim 1 , wherein the electrode length of the conductor wire includes a coating extending over all or a portion of the outer diameter surface thereof, the coating being one of: a TiN coating and a Pt coating. 
     
     
         4 . The lead of  claim 1 , wherein the conductor wire is formed of Pt/IR cladded Ta. 
     
     
         5 . The lead of  claim 1 , wherein the coil includes a distal end located in proximity to the electrode length of the conductor wire; and further comprising a conductive ring coupled to the distal end. 
     
     
         6 . The lead of  claim 1 , wherein the coil includes a distal end located in proximity to the electrode portion of the conductor wire; the distal end of the coil comprising a weld. 
     
     
         7 . The lead of  claim 6 , wherein the weld forms a ring structure, and the ring structure includes a slot extending therethrough. 
     
     
         8 . The lead of  claim 1 , comprising a plurality of the continuous conductor wires, such that the coil is a multi-filar coil. 
     
     
         9 . The lead of  claim 1 , further comprising an elongate insulated conductor extending within an inner diameter of the coil, and an electrode tip coupled to the insulated conductor and located distal to the electrode length of the conductor wire. 
     
     
         10 . A method for constructing an implantable medical electrical lead, the method comprising:
 flattening a radial cross-section profile of at least one conductor wire along a first length of an overall length of the wire to form an electrode length, the overall length of the at least one wire having been wound in a coil, and the coil extending from a proximal end thereof to a distal end thereof;   insulating a second length of the overall length of the at least one conductor wire; and   coupling a connector terminal contact to the proximal end of the coil;   wherein the first length of the at least one conductor wire extends proximally from the distal end of the coil; and   and the second length of the at least one conductor wire extends distally from the coupled connector terminal and toward the first length of the conductor wire.   
     
     
         11 . The method of  claim 10 , further comprising forming a coating on all or a portion of an outer surface of the first length of the conductor wire, after flattening the radial cross-section profile thereof, the coating comprising one of: a Pt coating, a native pentoxide coating, and a TiN coating. 
     
     
         12 . The method of  claim 10 , further comprising coupling a conductive ring to the distal end of the coil. 
     
     
         13 . The method of  claim 10 , further comprising welding the distal end of the coil. 
     
     
         14 . The method of  claim 13 , wherein the welding forms a ring-like structure; and further comprising forming a slot in the ring-like structure. 
     
     
         15 . The method of  claim 10 , wherein the at least one conductor wire comprises a plurality of conductor wires such that the coil is a multi-filar coil.