Fast detaching electronically isolated implant

• US 5,984,929 A
• Filed: 09/30/1997
• Issued: 11/16/1999
• Est. Priority Date: 08/29/1997
• Status: Expired due to Term

• Current Assignee: Stryker European Operations Holdings, LLC (Stryker Corporation)
• Original Assignee: Target Therapeutics, Inc. (Boston Scientific Corporation)
• Inventors: Bashiri, Mehran, Engelson, Erik T., Wallace, Michael P., Thach, Cong, Roue, Chad C., Pham, Pete Phong
• Primary Examiner(s): Buiz, Michael
• Assistant Examiner(s): TRUONG, KEVIN THAO
• Application Number:
  US08/941,458
• Time in Patent Office: 777 Days
• Field of Search: 606/108, 606/198, 606/192, 606/200, 606/1, 606/194
• US Class Current: 606/108
• CPC Class Codes: A61B 17/12022 Occluding by internal devices, e.g. balloons or releasable wires plugging an opening in the wall of an organ A61B17/0057; occluders for the cervical canal A61F6/146; vas deferens occluders A61F6/20
• CPC Class Codes: A61B 17/12113 within an aneurysm
• CPC Class Codes: A61B 17/12145 having a pre-set deployed three-dimensional shape methods of manufacturing A61B2017/00526
• CPC Class Codes: A61B 17/1215 comprising additional materials, e.g. thrombogenic, having filaments, having fibers, being coated
• CPC Class Codes: A61B 17/12154 having stretch limiting means
• CPC Class Codes: A61B 2017/12063 electrolytically detachable
• CPC Class Codes: A61F 2/0105 Open ended, i.e. legs gathered only at one side
• CPC Class Codes: A61F 2/011 Instruments for their placement or removal
• CPC Class Codes: A61F 2/95 Instruments specially adapted for placement or removal of stents or stent-grafts
• CPC Class Codes: A61F 2002/016 made from wire-like elements
• CPC Class Codes: A61F 2002/9505 having retaining means other than an outer sleeve, e.g. male-female connector between stent and instrument
• CPC Class Codes: A61F 2230/0006 circular
• CPC Class Codes: A61F 2230/005 Rosette-shaped, e.g. star-shaped
• CPC Class Codes: A61F 2230/0069 cylindrical
• CPC Class Codes: A61F 2230/0091 helically-coiled or spirally-coiled, i.e. having a 2-D spiral cross-section

Abstract

This is an implant for placement in the human body and an assembly for so placing that implant. Most desirably, it is an implant for use in the vasculature of the human body and is used to occlude some space in that vasculature as a portion of a treatment regimen. The implant itself is preferably a component of a deployment device using an electrolytically severable joint. The implant is electrically isolated from the electrolytically severable joint by a highly resistive or insulative layer. Such isolation and minimization of the conductive pathway from the placement apparatus to the body'"'"'s fluids appears to enhance the susceptibility of the electrolytic joint to quick erosion and detachment of the implant from the deployment media. Although the implant itself is preferably a vaso-occlusive device, it may instead be a stent, a vena cava filter, or other implant which may be installed in this manner.

Claims

1. An implant assembly for placement of an implant in the human body comprising:

(a.) an implant member having a proximal end and a distal end, and

(b.) a wire having an electrolytically severable joint, said wire attached to said implant member proximal end, said electrolytically severable joint being relatively more susceptible to electrolysis in an ionic solution than is said implant member,

wherein said implant member is electrically isolated from said electrolytically severable joint by a continuous, insulative or highly resistive layer disposed on said wire proximal of said joint and a continuous, insulative or highly resistive layer disposed on said wire distal of said joint.

2. The implant assembly of claim 1 additionally comprising a bushing disposed on a distal end of said wire separating said core wire from said implant member.

3. The implant assembly of claim 2 wherein said insulative or highly resistive layer comprises tantalum oxide.

4. The implant assembly of claim 2 wherein said insulative or highly resistive layer comprises a polymer.

5. The implant assembly of claim 4 wherein said insulative or highly resistive layer comprises a thermoplastic.

6. The implant assembly of claim 4 wherein said insulative or highly resistive layer comprises a member selected from the group consisting of polyethylene, polypropylene, polyamides, and polyethyleneterephthalate.

7. The implant assembly of claim 2 wherein said insulative or highly resistive layer comprises an oxide forming material.

8. The implant assembly of claim 1 wherein the implant member is a stent.

9. The implant assembly of claim 1 wherein the implant member comprises a vena cava filter.

10. The implant assembly of claim 1 wherein the implant member comprises a braid.

11. The implant assembly of claim 1 wherein the implant member comprises a helically wound coil.

12. The implant assembly of claim 11 wherein the helically wound coil implant member further comprises a stretch resistant member extending at least partially from said proximal end to said distal end.

13. The implant assembly of claim 12 wherein the stretch resistant member comprises a member selected from the group consisting of polyethylene, polypropylene, polyamides, and polyethyleneterephthalate.

14. The implant assembly of claim 11 further including a helically wound coil situated proximally in the lumen of said helically wound implant member and fixedly attached to said stretch resistant member.

15. The implant assembly of claim 14 wherein said helically wound coil situated proximally in the lumen of said helically wound implant member is welded to said helically wound implant member.

16. A method for introduction of an implant into a space within the human body comprising:

1.) placing a delivery catheter distal tip near a selected space within the human body,

2.) introducing an implant assembly comprising;

(i.) an implant member having a proximal end and a distal end, and

(ii.) an electrolytically severable joint attached to said proximal end of said implant member, said electrolytically severable joint being relatively more susceptible to electrolysis in an ionic solution than is said implant member,

wherein said implant member is electrically isolated from said electrolytically severable joint by a continuous, insulative or highly resistive layer disposed on said wire proximal of said joint and a continuous, insulative or highly resistive layer disposed on said wire distal of said joint,

into said catheter,

3.) placing said implant member into said selected space, and

4.) electrolytically detaching said implant member from said implant assembly.