Implant delivery system

• US 9,717,500 B2
• Filed: 04/15/2010
• Issued: 08/01/2017
• Est. Priority Date: 04/15/2009
• Status: Active Grant

• Current Assignee: Microvention Incorporated (Terumo Corporation)
• Original Assignee: Microvention Incorporated (Terumo Corporation)
• Inventors: Tieu, Tai D., Morita, Hideo, Nguyen, Helen
• Primary Examiner(s): Tyson, Melanie
• Assistant Examiner(s): COLELLO, ERIN L
• Application Number:
  US12/761,113
• Publication Number:
  US 20100268204A1
• Time in Patent Office: 2,665 Days
• Field of Search: 606200, 606 27- 28, 623 111
• 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 17/12154 having stretch limiting means
• CPC Class Codes: A61B 2017/12068 detachable by heat
• CPC Class Codes: A61B 90/39 Markers, e.g. radio-opaque or breast lesions markers
• CPC Class Codes: A61F 2/01 Filters implantable into blood vessels
• 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 2002/9505 having retaining means other than an outer sleeve, e.g. male-female connector between stent and instrument
• CPC Class Codes: A61F 2002/9511 the retaining means being filaments or wires
• CPC Class Codes: A61F 2250/0071 breakable or frangible

Abstract

A system and method of delivering and detaching an implant within a body of a patient is described. A tether connects an implant with a delivery device. The delivery device includes a heater coil through which the tether passes. The inner diameter of the heater coil is about the same size or slightly larger than the outer diameter of the tether, allowing the tether to more efficiently break the tether during delivery.

Claims

1. A delivery system for an implant comprising:

an elongated member having a distal end and a proximal end;

said distal end of said elongated member operable to hold said implant;

a tether member connectable to said elongated member and to said implant; and

,

a heating member comprising a resistance-type heater coil that is disposed on said elongated member;

said heating member having a hollow passage in which at least a portion of said tether member resides;

a first electrical wire connected at a distal end of said heater coil and a second electrical wire connected at a proximal end of said heater coil, wherein said first electrical wire and said second electrical wire supply direct current between said distal end of said heater coil and said proximal end of said heater coil;

said hollow passage comprising a first region having a first plurality of loops with a first internal diameter and a second region having a second plurality of loops with a second internal diameter that is different from said first diameter;

wherein said tether member passes through said first plurality of loops and said second plurality of loops; and

wherein said second diameter is substantially the same as an outer diameter of said tether member.

2. The delivery system of claim 1, wherein said tether has an external diameter of about 0.004 inch, said first internal diameter is about 0.007 inch and said second internal diameter is about 0.005 inch.

3. The delivery system of claim 1, wherein said heating member is an electrically actuated heating coil that is fixed along a side of said elongated member.

4. The delivery system of claim 1, wherein said implant is a stent having a plurality of cells and wherein said tether member is positioned through at least one of said plurality of cells.

5. The delivery system of claim 4, wherein said tether member passes through multiple cells of said plurality of cells.

6. The delivery system of claim 5, wherein said tether member maintains said stent in a compressed configuration.

7. A delivery system for an implant comprising:

a pusher member having an elongated shape;

a distal end of said pusher member connectable to said implant;

a tether for connecting said pusher member to said implant;

a resistance-type heating element mounted over said tether and supplied with direct current, said heating element having a first plurality of loops with a first internal diameter and a second plurality of loops with a second internal diameter that is smaller than said first internal diameter;

said tether passing through said first plurality of loops and said second plurality of loops;

wherein said heating element is controllable to generate a temperature increase that causes breakage of said tether.

8. The delivery system of claim 7, wherein said heating element has a tubular shape.

9. The delivery system of claim 8, wherein said second plurality of loops are positioned closer to said tether than said first plurality of loops.

10. The delivery system of claim 9, wherein said tether has an external diameter of about 0.004 inch, said second internal diameter is about 0.007 inch and said first internal diameter is about 0.005 inch.

11. The delivery system of claim 7, wherein said tether comprises at least three tether strands and wherein each of said at least three tether strands are fixed to said implant.

12. The delivery system of claim 7, wherein said implant is a stent having a plurality of cells and wherein said tether is located through at least some of said plurality of cells.

13. The delivery system of claim 12, wherein said tether maintains said stent in a compressed configuration.

14. An implant delivery system comprising:

an elongated member sized for insertion into a vascular system of a patient;

a resistance-type heater disposed on said elongated member, said heater having an interior passage and a heater length;

said heater length comprising a first region having a first internal passage diameter formed from a first plurality of loops and a second region having a second internal passage diameter formed from a second plurality of loops that is different than said first internal passage diameter;

a first electrical wire connected at a distal end of said heater and a second electrical wire connected at a proximal end of said heater;

wherein said first electrical wire and said second electrical wire supply direct current between said distal end of said heater and said proximal end of said heater;

a flexible tether member positioned through said first region and said second region of said interior passage of said heater;

said flexible tether being connectable to said implant so as to hold said implant to said elongated member.

15. The implant delivery system of claim 14, wherein said interior passage of said heater is sized to enclose only said tether.

16. The implant delivery system of claim 14, wherein said tether has an external diameter of about 0.004 inch, said first internal passage diameter is about 0.007 inch, and said second internal passage diameter is about 0.005 inch.

17. The implant delivery system of claim 14, wherein an outer surface of said heater is fixed to said elongated member.

18. A delivery system for an implant comprising:

an elongated member sized for insertion into a vascular system of a patient;

a heater disposed on said elongated member, said heater having an interior passage, said heater further comprising a first region having a first length formed from a first plurality of loops and a first internal passage diameter, and a second region having a second length formed from a second plurality of loops and a second internal passage diameter that is different than said first internal passage diameter;

a first electrical wire connected at a distal end of said heater and a second electrical wire connected at a proximal end of said heater;

wherein said first electrical wire and said second electrical wire supply direct current between said distal end of said heater and said proximal end of said heater;

a plurality of tether members positioned through said first length and said second length of said interior passage of said heater;

said plurality of tether members being connectable to said implant so as to hold said implant to said elongated member.

19. The delivery system of claim 18, wherein said plurality of tether members are connectable to a plurality of different locations of said implant.

20. A method of releasing an implant comprising:

providing a delivery device sized for insertion into a vascular system;

activating a resistance-type heater near a distal end of said delivery device where said implant is connected to said delivery device with a tether;

said heater having a passage forming a first portion having a first plurality of loops and a first internal passage diameter, and a second portion having a second plurality of loops and a second internal passage diameter that is different than said first internal passage diameter;

said tether positioned through said first portion and said second portion of said passage;

wherein said activating said heater further comprises delivering direct current through a first electrical wire connected at a distal end of said heater and through a second electrical wire connected at a proximal end of said heater;

heating said tether by circumferentially contacting a region of said tether with said first internal passage of said heater.

21. The method of claim 20, wherein said first internal passage diameter is smaller than said second internal passage diameter.

22. The method of claim 20, wherein said tether has an external diameter of about 0.004 inch, said second internal passage diameter is about 0.007 inch, and said first internal passage diameter is about 0.005 inch.