Thermal detachment system for implantable devices

• US 8,182,506 B2
• Filed: 08/25/2005
• Issued: 05/22/2012
• Est. Priority Date: 08/25/2004
• Status: Active Grant

• Current Assignee: Microvention Incorporated (Terumo Corporation)
• Original Assignee: Microvention Incorporated (Terumo Corporation)
• Inventors: Fitz, Matthew, Gulachenski, Joseph
• Primary Examiner(s): DOWE, KATHERINE MARIE
• Application Number:
  US11/212,830
• Publication Number:
  US 20060052815A1
• Time in Patent Office: 2,462 Days
• Field of Search: 606/200, 606 27- 41, 606/108, 623/1.11, 623/1.12
• US Class Current: 606/200
• CPC Class Codes: A61B 17/0057 Implements for plugging an opening in the wall of a hollow or tubular organ, e.g. for sealing a vessel puncture or closing a cardiac septal defect sutures A61B17/04; closing rectum or urethra near body surface A61F2/0009
• 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 17/12109 in a blood vessel
• CPC Class Codes: A61B 17/12113 within an aneurysm
• CPC Class Codes: A61B 17/12118 for positioning in conjunction with a stent
• CPC Class Codes: A61B 17/1214 Coils or wires
• CPC Class Codes: A61B 17/12145 having a pre-set deployed three-dimensional shape methods of manufacturing A61B2017/00526
• CPC Class Codes: A61B 17/12154 having stretch limiting means
• CPC Class Codes: A61B 17/1219 expandable in contact with liquids
• CPC Class Codes: A61B 2017/00575 for closure at remote site, e.g. closing atrial septum defects
• CPC Class Codes: A61B 2017/00637 for sealing trocar wounds through abdominal wall
• CPC Class Codes: A61B 2017/1205 Introduction devices
• CPC Class Codes: A61B 2017/12054 Details concerning the detachment of the occluding device from the introduction device
• CPC Class Codes: A61B 2017/12068 detachable by heat
• 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

Abstract

The present invention provides for implant delivery devices and methods of use. The delivery devices and methods of the present invention include a delivery pusher, an implant, a tether connected therebetween and a heater. Activation and application of the heater to the tether allows quick release of an implant into the vasculature of a human patient.

Claims

1. An implant delivery system comprising:

a. a delivery pusher;

b. an implant connected to said delivery pusher;

c. a tether connecting said implant to said delivery pusher, said tether having a distal end connected to said implant;

d. an electrical heating element associated with said tether;

wherein when activated, said heater causes said tether to break at a point proximal of said distal end such that a distal portion of said tether remains with said implant; and

wherein said tether is in a pre-tensioned state below the elastic limit of the tether material and wherein said implant device is released from said delivery pusher less than 1 second after activation of said electrical heating element, substantially due to said pre-tensioned state.

2. The implant delivery system of claim 1, wherein the pre-tension within said tether is less than about 250 grams.

3. The implant delivery system of claim 1, wherein the pre-tension in said tether is in a direction approximately co-axial to said delivery pusher.

4. The implant delivery system of claim 1, wherein activation of said electrical heating element releases potential energy.

5. The implant delivery system of claim 1, wherein said tether is comprised of a material selected from a group consisting of:

polypropylene, polyamide, ethylene vinyl alcohol, polyethylene, and polyolefin elastomer.

6. The implant delivery system of claim 1, wherein the temperature of said delivery pusher is less than about 50°

C. when said implant detaches from said delivery pusher.

7. The implant delivery system of claim 6, wherein the temperature of said delivery pusher is less than about 42°

C. when said implant detaches from said delivery pusher.

8. The implant delivery system of claim 1, wherein said implant is a coil.

9. The implant delivery system of claim 1, wherein said implant is a stent.

10. The implant delivery system of claim 1, wherein said tether has a diameter within the range of about 0.001 to 0.007 inches.

11. The implant delivery system of claim 1, wherein the electrical heating element comprises a heating element adjacent to a portion of said tether.

12. The implant delivery system of claim 11, wherein said electrical heating element comprises solid metallic heating element.

13. A method of releasing an implant from a delivery device comprising:

a. providing a delivery device having an implant connected to said delivery device with a tether, said tether having been axially tensioned to lower a required detachment time and temperature for said tether to sever and break when heated;

b. positioning said implant at a target location within a lumen of a patient;

c. activating a heater associated with said tether of said delivery device such that said tether is broken at a point proximal of said implant and said implant is released, along with a distal remains of said tether, from said delivery device in less than about 1 second after activation of said heater.

14. The method of claim 13, wherein said implant is released from said delivery device about 0.75 seconds after said heater is activated.

15. The method of claim 13, wherein the providing of a delivery device includes providing said tether in a pre-tensioned state.

16. The method of claim 15, wherein the pre-tension within said tether is less than about 250 grams.

17. The implant delivery system of claim 15, wherein the pre-tension in said tether is in a direction approximately co-axial to said delivery pusher.

18. The method of claim 13, wherein the activating of said heater includes applying current to said heater selected from a group consisting of alternating current, direct current, and radio frequency current.

19. The method of claim 13, wherein the activating of said heater causes the surface temperature of said delivery device to be less than about 50°

C.

20. The method of claim 19, wherein the activating of said heater causes the surface temperature of said delivery device to be less than about 42°

C.

21. The method of claim 13 wherein activating a heater of said delivery device comprises sending electrical current through a heating element that is adjacent said tether.

22. The implant delivery system of claim 21, wherein said heater comprises solid metallic heating element.

23. An implant delivery system comprising:

a. a delivery pusher having an outer surface;

b. an implant connected to said delivery pusher;

c. a tether connecting said implant to said delivery pusher;

d. an electrical heating element associated with said tether to heat said tether at a breaking point proximal of where said tether is connected to said implant;

wherein said tether is elongated in order to create a pre-tensioned state below the elastic limit of the tether material said pre-tensioned state causing said implant device to be released from said delivery pusher, along with a portion of said tether distal of said breaking point, after activation of said electrical heating element and prior to a temperature of said outer surface of said delivery pusher exceeding about 50°

C.

24. The implant delivery system of claim 23, wherein the pre-tension in said tether is less than about 200 grams.

25. The implant delivery system of claim 23, wherein the pre-tension in said tether is in a direction approximately co-axial to said delivery pusher.

26. The implant delivery system of claim 23, wherein activation of said electrical heating element releases potential energy.

27. The implant delivery system of claim 23, wherein said tether is comprised of a material selected from a group consisting of:

polypropylene, polyamide, ethylene vinyl alcohol, polyethylene, and polyolefin elastomer.

28. The implant delivery system of claim 23, wherein the outer surface temperature of said delivery pusher is less than about 42°

C. when said implant detaches from said delivery pusher.

29. The implant delivery system of claim 23, wherein said delivery system is adapted to release said implant device from said delivery pusher less than about 1 second after activation of said electrical heating element.

30. The implant delivery system of claim 29, wherein said delivery system is adapted to release said implant device from said delivery pusher less than 0.75 seconds after activation of said electrical heating element.

31. The implant delivery system of claim 23, wherein said implant is a coil.

32. The implant delivery system of claim 23, wherein said implant is a stent.

33. The implant delivery system of claim 23 wherein said tether has a diameter within the range of about 0.001 to 0.007 inches.

34. The implant delivery system of claim 23, wherein the electrical heating element comprises a heating element adjacent to a portion of said tether.

35. The implant delivery system of claim 34, wherein said electrical heating element comprises solid metallic heating element.

36. An implant delivery system comprising:

a. a delivery pusher;

b. an implant connected to said delivery pusher;

c. a tether connecting said implant to said delivery pusher;

d. a heater in close proximity to said tether at a breaking point proximal of said implant, and,

e. a tensioning mechanism placing said tether in an elastically deformed tensioned state so that release of said implant from said delivery pusher occurs by releasing potential energy from said tensioned state thereby applying a force on said implant, thereby releasing said implant with a portion of said tether distal of said breaking point.

37. The implant delivery system of claim 36, wherein said force is less than 250 grams.

38. The implant delivery system of claim 36, wherein said force is applied in a direction approximately co-axial to said delivery pusher.

39. An implant according to claim 36, wherein said tether has a diameter within the range of about 0.001 to 0.007 inches.

40. The implant delivery system of claim 36, wherein said tensioning mechanism comprises a spring.

41. The implant delivery system of claim 36, wherein said tensioning mechanism comprises a portion of said implant.

42. The implant delivery system of claim 41, wherein said implant comprises a coil.