Locking mechanisms for fixation devices and methods of engaging tissue

• US 20060020275A1
• Filed: 05/16/2005
• Published: 01/26/2006
• Est. Priority Date: 04/09/1999
• Status: Active Grant

• Current Assignee: Evalve, Inc. (Abbott Laboratories Incorporated)
• Original Assignee: Evalve, Inc. (Abbott Laboratories Incorporated)
• Inventors: Sarabia, Jaime E., Raschdorf, Alfred H., Goldfarb, Eric A., Madden, John P.
• Granted Patent: US 7,604,646 B2
• Time in Patent Office: Days
• US Class Current: 606/151
• CPC Class Codes: A61B 17/00234 for minimally invasive surgery A61B17/0218, A61B17/0469, A61B17/12013, A61B17/1285, A61B17/29, A61B17/320016 take precedence
• CPC Class Codes: A61B 17/08 Wound clamps or clips, i.e. not or only partly penetrating the tissue suture bridges A61B17/0466; Devices for bringing together the edges of a wound
• CPC Class Codes: A61B 17/10 for applying or removing wound clamps, e.g. containing only one clamp or staple A61B17/076 takes precedence; containing multiple wound clamps A61B17/068; Wound clamp magazines containers, packaging elements or packages specially adapted for particular articles or with special means for dispensing contents B65D83/00, B65D85/00
• CPC Class Codes: A61B 17/122 Clamps or clips , e.g. for the umbilical cord for the vas deferens A61F6/206
• CPC Class Codes: A61B 17/1285 for minimally invasive surgery
• CPC Class Codes: A61B 17/2909 Handles
• CPC Class Codes: A61B 2017/00243 cardiac
• CPC Class Codes: A61B 2017/00783 Valvuloplasty
• CPC Class Codes: A61B 2017/2946 Locking means
• CPC Class Codes: A61F 2/2442 Annuloplasty rings or inserts for correcting the valve shape; Implants for improving the function of a native heart valve
• CPC Class Codes: A61F 2/246 Devices for obstructing a leak through a native valve in a closed condition

Abstract

Devices, systems and methods are provided for tissue approximation and repair at treatment sites. In particular, fixation devices are provided comprising a pair of elements each having a first end, a free end opposite the first end, and an engagement surface therebetween for engaging the tissue, the first ends being moveable between an open position wherein the free ends are spaced apart and a closed position wherein the free ends are closer together with the engagement surfaces generally facing each other. The fixation devices also include a locking mechanism coupled to the elements for locking the elements in place. The devices, systems and methods of the invention will find use in a variety of therapeutic procedures, including endovascular, minimally-invasive, and open surgical procedures, and can be used in various anatomical regions, including the abdomen, thorax, cardiovascular system, heart, intestinal tract, stomach, urinary tract, bladder, lung, and other organs, vessels, and tissues. The invention is particularly useful in those procedures requiring minimally-invasive or endovascular access to remote tissue locations, where the instruments utilized must negotiate long, narrow, and tortuous pathways to the treatment site.

Claims

1. A fixation device for engaging tissue comprising:

a pair of elements each having a first end, a free end opposite the first end, and an engagement surface therebetween for engaging the tissue, the first ends being movable between an open position wherein the free ends are spaced apart and a closed position wherein the free ends are closer together with the engagement surfaces generally facing each other; and

a locking mechanism coupled to the elements for locking the elements in place.

2. A fixation device as in claim 1, further comprising a moveable stud coupled to the elements wherein movement of the stud moves the elements between the positions.

3. A fixation device as in claim 2, wherein the locking mechanism comprises an engagement element engageable with the moveable stud wherein engagement restricts movement of the stud.

4. A fixation device as in claim 3, wherein the engagement element comprises at least one wedging element which frictionally engages the moveable stud to restrict movement of the stud.

5. A fixation device as in claim 3, wherein the engagement element has at least one protrusion which mates with at least one external groove on the stud so as to restrict movement of the stud.

6. A fixation device as in claim 2, wherein the locking mechanism comprises an interference element which is positionable along the moveable stud so that the interference element prevents movement of the moveable stud in at least a first direction by contacting a stationary surface of the fixation device.

7. A fixation device as in claim 6, wherein the interference element comprises a locking sheath advanceable over the moveable stud so that the locking sheath prevents movement of the stud in the at least first direction by abutting against the stationary surface.

8. A fixation device as in claim 6, wherein the moveable stud includes external grooves and wherein the interference element comprises a lock nut mateable with the external grooves of the moveable stud so that the mated lock nut prevents movement of the stud in at least the first direction by abutting against the stationary surface.

9. A fixation device as in claim 1, wherein the moveable stud comprises a flexible line.

10. A fixation device as in claim 9, wherein the locking mechanism comprises an interference element which is positionable along the flexible line so that the interference element prevents movement of the flexible line in at least a first direction by contacting a stationary surface of the fixation device.

11. A fixation device as in claim 1, wherein the locking mechanism comprises gears, wherein movement of the gears moves the elements between the positions while locking the elements in place at each position.

12. A fixation device as in claim 1, wherein the locking mechanism comprises a biasing member which biases the elements toward one of the positions.

13. A fixation device as in claim 12, wherein the biasing member comprises a pair of spring loaded support sleeves positionable against a portion of the fixation device so as to bias the elements toward one of the positions.

14. A fixation device as in claim 12, wherein the biasing member comprises a cinching band positionable around the elements so as to bias the elements toward one of the positions.

15. A fixation device as in claim 14, wherein the cinching band comprises an elastic cinching band positionable around the elements in a stretched configuration so as to apply biasing force to the elements.

16. A fixation device as in claim 14, wherein the cinching band comprises a cinching line positionable around the elements in a lasso configuration so as to apply biasing force to the elements when tightened.

17. A fixation device as in claim 1, further comprising at least one leg joined with the elements so that movement of the at least one leg moves the elements between the positions.

18. A fixation device as in claim 17, wherein the at least one leg has a spring loaded configuration so as to bias the elements toward one of the positions.

19. A fixation device as in claim 17, wherein the locking mechanism comprises a structure joinable with the at least one leg so as to prevent movement of the elements.

20. A fixation device as in claim 19, wherein the structure comprises a barb advanceable through the at least one leg.

21. A fixation device as in claim 1, further comprising an unlocking mechanism for disengaging the locking mechanism.

22. A fixation device for engaging tissue comprising:

a pair of elements each having a first end, a free end opposite the first end, and an engagement surface therebetween for engaging the tissue, the first ends being moveable between an open position wherein the free ends are spaced apart and a closed position wherein the free ends are closer together with the engagement surfaces generally facing each other; and

a locking mechanism coupled to the elements for locking the elements in place along a continuum of positions between the open position and the closed position.

23. A fixation device as in claim 22, further comprising an unlocking mechanism for disengaging the locking mechanism so the elements are moveable.

24. A fixation device as in claim 22, further comprising a moveable stud coupled to the elements wherein movement of the stud moves the elements between the positions, the locking mechanism comprising at least one wedging element for frictionally engaging the stud to restrict movement thereof.

25. A fixation device as in claim 24, wherein the at least one wedging element comprises a binding plate having a first end, a second end and a portion therebetween shaped to engage the stud, the binding plate positioned so that the portion is disposed near the stud.

26. A fixation device as in claim 25, wherein the portion shaped to engage the stud at least partially surrounds the stud, the binding plate positioned so that the portion at least partially surrounds the stud.

27. A fixation device as in claim 26, wherein the portion shaped to at least partially surround the stud comprises an aperture, the binding plate positioned so that the stud passes through the aperture.

28. A fixation device as in claim 27, wherein the locking mechanism further comprises a spring which forces the aperture against the stud to restrict movement of the stud through the aperture.

29. A fixation device as in claim 25, further comprising an unlocking mechanism for disengaging the locking mechanism, wherein the unlocking mechanism comprises a harness, the harness adapted to move the second end while the first end remains substantially stationary so as to reduce frictional engagement of the at least partially surrounding portion with the stud.

30. A fixation device as in claim 24, wherein the at least one wedging element comprises at least one cam, the at least one cam pivotable to frictionally engage the stud to restrict movement thereof.

31. A fixation device as in claim 30, wherein the at least one cam has an inward surface engageable with the stud and an outward surface connected with a spring which forces the inward surface against the stud to restrict movement of the stud.

32. A fixation device as in claim 31, further comprising an unlocking mechanism for disengaging the locking mechanism, wherein the unlocking mechanism comprises at least one actuator attached to a pivot point on each of the at least one cams, the at least one actuator adapted to pivot the at least one cam about its pivot point to reduce frictional engagement of the inner surface with the stud.

33. A fixation device as in claim 30, wherein the at least one cam comprises two cams, each cam disposed on opposite sides of the stud.

48. A locking mechanism as in claim 32, wherein the unlocking mechanism comprises at least one actuator attached to a pivot point on each of the at least one cams, the at least one actuator adapted to pivot the at least one cam about its pivot point to reduce frictional engagement of the inner surface with the stud.

59. A lockable system as in claim 48, wherein the grasper includes at least one pullwire fixedly attached to the stud so that movement of the stud moves the at least one pullwire which actuates movement of the portion of the grasper to the desired position.

34. A fixation device for engaging tissue comprising:

a pair of elements each having a first end and a free end opposite the first end, the first ends being moveable within a range between an open position wherein the free ends are spaced apart and a closed position wherein the free ends are closer together; and

a locking mechanism coupled to the elements for locking the elements in a position which allows movement of the elements within a sub-range of the range.

35. A device as in claim 34, further comprising a moveable stud coupled to the elements wherein movement of the stud moves the elements between the positions within the range, the stud having at least one external groove for engagement by at least one wedging element wherein the at least one external groove is sized to allow shifting of the at least one wedging element within the at least one external groove which allows movement of the elements within the sub-range.

36. A device as in claim 34, further comprising a moveable stud coupled to the elements wherein movement of the stud moves the elements between the positions within the range, the locking mechanism comprising at least one wedging element for frictionally engaging the stud to restrict movement thereof.

37. A device as in claim 36, wherein the at least one wedging element comprises an at least partially flexible material wherein flexing of the material allows movement of the elements within the sub-range.

38. A device as in claim 37, wherein the at least one wedging element comprises a binding plate having a first end, a second end and a portion therebetween shaped to at least partially surround the stud, the binding plate positioned so that the portion at least partially surrounds the stud.

39. A device as in claim 38, wherein the portion shaped to at least partially surround the stud comprises an aperture, the binding plate positioned so that the stud passes through the aperture.

40. A device as in claim 34, wherein the elements are configured for engaging valve leaflets of a valve within a heart, and movement of the fixation elements within the sub-range is achievable by force caused by dynamic fluid flow through the valve.

41. A locking mechanism comprising:

a moveable stud coupled to a device, wherein movement of the stud actuates movement of a portion of a device to a desired position in a range from a first position to a second position;

at least one element configured to engage the stud to restrict movement of the stud which locks the device in the desired position; and

an unlocking mechanism configured to disengage the at least one element from the stud which allows movement of the stud.

42. A locking mechanism as in claim 41, wherein the at least one element comprises a binding plate having a first end, a second end and a portion therebetween shaped to at least partially surround the stud, the binding plate positioned so that the portion at least partially surrounds the stud.

43. A locking mechanism as in claim 42, wherein the portion shaped to at least partially surround the stud comprises an aperture, the binding plate positioned so that the stud passes through the aperture.

44. A locking mechanism as in claim 43, further comprising a spring configured to force the aperture against the stud to restrict movement of the stud through the aperture.

45. A locking mechanism as in claim 42, wherein the unlocking mechanism comprises a harness, the harness adapted to move the second end while the first end remains substantially stationary so as to reduce frictional engagement of the at least partially surrounding portion with the stud.

46. A locking mechanism as in claim 41, wherein the at least one element comprises at least one cam, the at least one cam pivotable to frictionally engage the stud to restrict movement thereof.

47. A locking mechanism as in claim 46, wherein the at least one cam has an inward surface engageable with the stud and an outward surface connected with a spring which forces the inward surface against the stud to restrict movement of the stud.

49. A locking mechanism as in claim 41, wherein the stud has at least one external groove for engagement with the at least one element to restrict movement of the stud.

50. A locking mechanism as in claim 49, wherein the at least one element comprises at least one protrusion which mates with the at least one external groove of the stud wherein the at least one element is moveable to engage the at least one protrusion with the at least one external groove of the stud to restrict movement of the stud.

51. A locking mechanism as in claim 50, wherein the unlocking mechanism comprises a hinge component which moves the at least one element to disengage the at least one protrusion from the at least one external groove.

52. A locking mechanism as in claim 50, wherein the at least one external groove comprises threads and the at least one element comprises a split nut.

53. A locking mechanism as in claim 41, wherein the desired position includes any position between the first position and the second position.

54. A locking mechanism as in claim 41, wherein the desired position includes one of a series of predetermined positions between the first position and the second position.

55. A lockable system comprising:

a device having a portion which is moveable to a desired position; and

a locking mechanism coupled to the device comprising

a moveable stud configured so that movement of the stud actuates movement of the portion of the device to the desired position,

at least one element configured to engage the stud to restrict movement of the stud which locks the device in the desired position, and

an unlocking mechanism configured to disengage the at least one element from the stud which allows movement of the stud.

56. A lockable system as in claim 55, wherein the device comprises a catheter.

57. A lockable system as in claim 56, wherein the catheter includes at least one pullwire fixedly attached to the stud so that movement of the stud moves the at least one pullwire which actuates movement of the portion of the catheter to the desired position.

58. A lockable system as in claim 55, wherein the device comprises a grasper.

60. A lockable system as in claim 55, wherein the device comprises a retractor.