VASO-OCCLUSIVE DEVICE DELIVERY SYSTEM

• US 20140277092A1
• Filed: 03/12/2014
• Published: 09/18/2014
• Est. Priority Date: 03/14/2013
• Status: Active Grant

• Current Assignee: Stryker European Operations Holdings, LLC (Stryker Corporation)
• Original Assignee: Stryker Corporation, Stryker Nv Operations Limited (Stryker Corporation)
• Inventors: Teoh, Clifford, Chen, Hancun, Guo, Lantao, Murphy, Richard, Odell, Timothy
• Granted Patent: US 9,717,502 B2
• Time in Patent Office: Days
• US Class Current: 606/200
• CPC Class Codes: A61B 17/12031 complete occlusion
• CPC Class Codes: A61B 17/1214 Coils or wires
• CPC Class Codes: A61B 17/12154 having stretch limiting means
• CPC Class Codes: A61B 2017/12068 detachable by heat
• CPC Class Codes: A61B 2017/12077 Joint changing shape upon application of heat, e.g. bi-metal or reversible thermal memory
• CPC Class Codes: A61B 2017/1209 detachable by electrical current or potential, e.g. electroactive polymer

Abstract

A vaso-occlusive device delivery assembly includes a pusher assembly having proximal and distal ends, a conductive sacrificial link disposed at the distal end of the pusher assembly, and a vaso-occlusive device secured to the pusher assembly by the sacrificial link. The pusher assembly includes first and second conductors extending between the proximal and distal ends thereof. The sacrificial link is electrically coupled between the first and second conductors, such that the first conductor, sacrificial link and second conductor form an electrical circuit, and, when a disintegration current is applied through the sacrificial link through the first and second conductors, the sacrificial link thermally disintegrates, thereby releasing the attachment member and vaso-occlusive device from the pusher assembly.

Claims

1. A vaso-occlusive device delivery assembly, comprising:

a pusher assembly having proximal and distal ends and comprising

first and second conductors extending between the proximal and distal ends of the pusher assembly, and

a thermally-degradable conductive sacrificial link disposed at the distal end of the pusher assembly and electrically coupled between the respective first and second conductors, such that the first conductor, the sacrificial link, and the second conductor form an electrical circuit; and

a vaso-occlusive device secured to the pusher assembly by the sacrificial link,

wherein the sacrificial link is configured to generate heat that thermally disintegrates the sacrificial link when a disintegration current is applied through the sacrificial link, thereby releasing the vaso-occlusive device from the pusher assembly.

2. The vaso-occlusive device delivery assembly of claim 1, further comprising an attachment member secured to the vaso-occlusive device and secured to the pusher assembly by the sacrificial link.

3. The vaso-occlusive device delivery assembly of claim 2, the attachment member comprising a meltable tether,

wherein the meltable tether is configured such that, when a heating current, less than the disintegration current, is applied through the sacrificial link, the sacrificial link is heated by resistive heating to a temperature sufficient to sever the meltable tether without disintegrating the sacrificial link, thereby detaching the vaso-occlusive device from the pusher assembly.

4. The vaso-occlusive device delivery assembly of claim 3, further comprising a power supply electrically connected to the first and second conductors, wherein the power supply is controllable to selectively deliver the disintegration current or the heating current through the sacrificial link.

5. The vaso-occlusive device delivery assembly of claim 3, further comprising a third conductor extending between the proximal and distal ends of the pusher assembly and electrically connected to the sacrificial link, such that the third conductor, sacrificial link, and second conductor form an electrical circuit, wherein the third conductor has a greater resistivity than the first conductor, such that, when the disintegration current is applied through the sacrificial link through the third and second conductors, the sacrificial link is heated by resistive heating to a temperature sufficient to melt the tether without disintegrating the sacrificial link.

6. The vaso-occlusive device delivery assembly of claim 1, the pusher assembly further comprising first and second load bearing connectors that electrically and mechanically connect the sacrificial link to the respective first and second conductors.

7. The vaso-occlusive device delivery assembly of claim 6, wherein the sacrificial link and the load bearing conductor are mechanically tied to each other.

8. The vaso-occlusive device delivery assembly of claim 1, wherein the sacrificial link comprises titanium or titanium alloy.

9. The vaso-occlusive device delivery assembly of claim 1, wherein the sacrificial link comprises magnesium or magnesium alloy.

10. The vaso-occlusive device delivery assembly of claim 1, wherein the sacrificial link comprises an electrically conductive polymer.

11. The vaso-occlusive device delivery assembly of claim 10, wherein the electrically conductive polymer is selected from the group consisting of polyacetylene, polypyrrole, polyaniline, poly(p-phenylene vinylene), poly(thiophene), poly(3,4-ethylenedioxythiophene), and poly(p-phenylene sulfide).

12. The vaso-occlusive device delivery assembly of claim 10, wherein the electrically conductive polymer is a powder-filled or fiber-filled composite polymer.

13. The vaso-occlusive device delivery assembly of claim 1, the pusher assembly further comprising a cylindrical body disposed around and thermally insulating the sacrificial link, wherein the cylindrical body includes a cavity in which the sacrificial link is located.

14. The vaso-occlusive device delivery assembly of claim 1, wherein the sacrificial link comprises an electrically conductive polymer tube.

15. The vaso-occlusive device delivery assembly of claim 14, wherein the electrically conductive polymer tube includes an axial lumen, and wherein a distal end of the first conductor is disposed within the axial lumen.

16. The vaso-occlusive device delivery assembly of claim 1, further comprising:

a proximal tubular member disposed in a lumen of the pusher and attached to the pusher assembly; and

a distal tubular member disposed in a lumen of the vaso-occlusive device and attached to the vaso-occlusive device,

wherein a proximal portion of the sacrificial link extends through the proximal connector member, a distal portion of the sacrificial link extends through the distal connector member, and an exposed middle portion of the sacrificial link is disposed between the proximal and distal connector members, and

wherein the sacrificial link is configured to generate heat that thermally disintegrates the middle portion when the disintegration current is applied through the sacrificial link, thereby releasing the vaso-occlusive device from the pusher assembly.

17. The vaso-occlusive device delivery assembly of claim 16, the vaso-occlusive device comprising a stretch-resisting member having a distal end secured to a distal portion of the vaso-occlusive device, wherein a distal end connector portion of the sacrificial link extends distally of the distal connector member, and is secured to a proximal end of the stretch-resisting member.

18. A vaso-occlusive device delivery assembly, comprising:

a pusher assembly having proximal and distal ends with first and second conductors extending between the proximal and distal ends; and

a vaso-occlusive device releasably coupled to the pusher assembly by a connector member, the connector member comprising

a proximal connecting member coupled to the pusher assembly,

a distal connecting member coupled to the vaso-occlusive device, and

a thermally-degradable sacrificial member electrically connected to the first and second conductors, the sacrificial member comprising a proximal portion coupled to the proximal connecting member and a distal portion extending distally of the proximal connecting member and coupled to the distal connecting member to thereby attach the pusher assembly to the vaso-occlusive device,

wherein the sacrificial member generates heat that thermally disintegrates the sacrificial member when a disintegration current is applied through the sacrificial link, thereby releasing the vaso-occlusive device from the pusher assembly.

19. The vaso-occlusive device delivery assembly of claim 18, wherein the proximal and distal connectors each have a flattened profile.

20. The vaso-occlusive device delivery assembly of claim 19, wherein the pusher assembly further comprises a distal end coil having open pitch windings,

wherein the proximal connector member defines a plurality of fingers that are interlaced between adjacent open pitched windings of the pusher assembly distal end coil,

wherein the vaso-occlusive member comprises a vaso-occlusive coil having open pitch windings at a proximal end thereof, and

wherein the distal connector member defines a plurality of fingers that are interlaced between adjacent open pitched windings at the proximal end of the vaso-occlusive coil.