Fast detaching electrically isolated implant

• US 6,468,266 B1
• Filed: 08/22/2000
• Issued: 10/22/2002
• Est. Priority Date: 08/29/1997
• Status: Expired due to Term

• Current Assignee: Stryker European Operations Holdings, LLC (Stryker Corporation)
• Original Assignee: Scimed Life Systems Incorporated (Boston Scientific Corporation)
• Inventors: Thach, Cong, Eder, Joseph C., Bashiri, Mehran, Engelson, Erik T., Wallace, Michael P., Roue, Chad C., Pham, Pete Phong
• Primary Examiner(s): TRUONG, KEVIN THAO
• Application Number:
  US09/644,244
• Time in Patent Office: 791 Days
• Field of Search: 606/108, 606/151, 606/191, 606/194, 606/198, 606/200, 606/1, 606/127, 606/114
• US Class Current: 606/1
• 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:

an implant,

a wire having an electrolytically severable joint, the wire attached to a proximal end of the implant, the electrolytically severable joint being relatively more susceptible to electrolysis in an ionic solution than is the implant, and

a wire anchoring member disposed distally of the joint and attached to the implant,

wherein the implant is electrically isolated from the electrolytically severable joint.

2. The implant assembly of claim 1 wherein the electrical isolation is due to an insulative or highly resistive layer interposed between the implant and the electrolytically severable joint.

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

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

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

6. The implant assembly of claim 5 wherein the helically wound coil is further wound into a secondary shape.

7. The implant assembly of claim 6 wherein the secondary shape is helical.

8. The implant assembly of claim 7 wherein the secondary shape is conical.

9. The implant assembly of claim 6 wherein the helically wound coil self-forms into the secondary shape when unconstrained.

10. The implant assembly of claim 5 wherein the helically wound coil is further wound into two secondary shapes having differing secondary shape diameters.

11. The implant assembly of claim 1 wherein the wire anchoring member comprises a hook.

12. The implant assembly of claim 1 wherein the wire anchoring member comprises a coil.

13. The implant assembly of claim 1 wherein the wire anchoring member comprises a loop.

14. The implant assembly of claim 1 wherein the wire anchoring member comprises an oxide forming material.

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

a vaso-occlusive implant,

a wire having an electrolytically severable joint, the wire attached to a proximal end of the implant, the electrolytically severable joint being relatively more susceptible to electrolysis in an ionic solution than is the implant,

an anchoring member disposed distally of the joint and attached to the implant via a stretch resistant member,

wherein the implant is electrically isolated from the electrolytically severable joint.

16. The implant assembly of claim 15 wherein the stretch resistant member comprises a material selected from the group consisting of polyethylene, polypropylene, polyamides, and polyethyleneterephthalate.

17. The implant assembly of claim 15 wherein the vaso-occlusive implant comprises a helical coil.

18. The implant assembly of claim 15 wherein a distal end of the wire is covered with a first insulative or highly resistive layer and the wire distal end is attached to the implant member proximal end by a second insulative or highly resistive layer.

19. The implant assembly of claim 15 wherein the electrical isolation is due to an insulative or highly resistive layer interposed between the implant and the electrolytically severable joint.

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

a vaso-occlusive coil,

a wire having an electrolytically severable joint, the wire affixed to a proximal end of the coil, the electrolytically severable joint being relatively more susceptible to electrolysis in an ionic solution than is the coil, and

an anchoring member disposed distally of the joint and affixed to the coil, the anchoring member comprising a loop affixed to a stretch resistant member, the stretch resistant member affixed to the coil,

wherein the coil is electrically isolated from the electrolytically severable joint.

21. The implant assembly of claim 20 additionally comprising a polymeric region disposed (a) distally of the anchoring member and (b) at least partially in a proximal portion of the coil.

22. The implant assembly of claim 20 wherein the anchoring member has a diameter that is larger than a diameter of a lumen of the coil so that a portion of the anchoring member is prevented from passing through the coil lumen upon application of force on the coil.

23. The implant assembly of claim 20 additionally comprising a radiopaque coil disposed on the wire distal of the electrolytically severable joint.

24. The implant assembly of claim 23 wherein a distal portion of the wire and at least a portion of the radiopaque coil is attached to the anchoring member and the coil via an insulative or highly resistive member disposed distal to the joint.