Expandable annuloplasty ring

• US 6,217,610 B1
• Filed: 07/29/1998
• Issued: 04/17/2001
• Est. Priority Date: 07/29/1994
• Status: Expired due to Term

• Current Assignee: Edwards Lifesciences Corporation
• Original Assignee: Edwards Lifesciences Corporation
• Inventors: Nguyen, Than, Cunanan, Crystal, Huynh, Van Le, Carpentier, Alexandre, Carpentier, Alain, Lam, Hung
• Primary Examiner(s): SNOW, BRUCE EDWARD
• Application Number:
  US09/124,657
• Time in Patent Office: 993 Days
• Field of Search: 623/2.37, 623/2.36, 623/900
• US Class Current: 623/2.37
• CPC Class Codes: A61F 2/2448 D-shaped rings
• CPC Class Codes: A61F 2250/0004 adjustable
• CPC Class Codes: A61F 2250/0082 specially designed for children, e.g. having means for adjusting to their growth

Abstract

An expandable annuloplasty ring which may either expand spontaneously, in situ, as the patient grows or be expanded by surgical intervention by balloon dilatation. The distensible annuloplasty ring of the invention may be usable in pediatric patients whose growth, subsequent to surgical implantation of the ring, will necessitate subsequent enlargement of the ring to accommodate growth of the annulus. The ring may include relatively expandable segments to enable the enlargement thereof. The ring segments may include engaging teeth which cooperate with notches or slots formed in the tubes to provide some resistance to ring distention, while preventing collapse of the ring in the opposite direction. The teeth may be of different sizes or shapes to regulate the amount of force needed to expand the ring at different stages of the patient'"'"'s growth. Alternatively, the adjustable ring includes a solid core of non-elastic material which plastically retains its shape upon natural expansion of the annulus, or after surgical expansion. In one embodiment, segments are coupled together with a discontinuity around the ring periphery. Pivot regions are provided between adjacent segments that, along with the discontinuity, enable the ring to expand upon annulus growth. The discontinuity may be positioned along the anterior side of the ring or around the posterior side. A further version makes use of telescoped segments with no discontinuity. The segments are coupled together with tubular sheaths, and expand without decoupling. A fabric covering may be omitted.

Claims

1. An expandable annuloplasty ring for implantation in a heart valve annulus that is not fully developed, comprising:

a plurality of relatively rigid ring segments defining a periphery of the ring, the ring segments being coupled together with at least two of the segments being relatively movable with respect to one another to enable substantial expansion of the ring periphery upon natural growth of the annulus to a larger size.

2. The annuloplasty ring of claim 1, wherein the periphery is discontinuous and the ring segments are coupled end-to-end by flexible sheaths enabling relative translation movement therebetween.

3. The annuloplasty ring of claim 2, further including a tubular fabric covering surrounding the ring segments and sheaths.

4. The annuloplasty ring of claim 2, wherein opposed ends of adjacent ring segments are initially juxtaposed within the sheaths, the segments being adapted to slide within the sheaths and separate to expand the ring.

5. The annuloplasty ring of claim 1, wherein the ring segments are formed of titanium.

6. The annuloplasty ring of claim 2, wherein the sheaths are formed of silicone.

7. The annuloplasty ring of claim 1, wherein the annuloplasty ring is shaped to support a mitral annulus, the periphery generally being formed in a D-shape with a straight side and a convex side, the ring including two identical ring segments having two pairs of juxtaposed ends, one pair of the juxtaposed ends being on the straight side of the periphery, and the other pair of the juxtaposed ends being on the convex side of the periphery.

8. The annuloplasty ring of claim 1, wherein the annuloplasty ring is shaped to support a mitral annulus, the periphery generally being formed in a D-shape with a straight side and a convex side, the ring including three ring segments, two of the ring segments having a pair of juxtaposed ends located on the straight side of the periphery, and a third ring segment being arcuate and centered on the convex side of the periphery.

9. The annuloplasty ring of claim 1, wherein the periphery includes a discontinuity between two of the ring segments.

10. The annuloplasty ring of claim 9, wherein the ring segments are coupled end-to end to pivot with respect to one another.

11. The annuloplasty ring of claim 10, wherein there are at least three ring segments and two end-to-end pivoting couples.

12. The annuloplasty ring of claim 11, wherein the annuloplasty ring is shaped to support a mitral annulus, the periphery generally being formed in a D-shape with a straight side and a convex side.

13. The annuloplasty ring of claim 12, wherein there are three ring segments and two end-to-end pivoting couples, and the discontinuity is located between two of the ring segments in the midpoint of the convex side of the periphery.

14. The annuloplasty ring of claim 13, wherein a first one of the ring segments extends substantially the length of the straight side of the D-shaped periphery, with the two other ring segments being pivotally connected to the first ring segment.

15. The annuloplasty ring of claim 10, wherein the ring segments comprise a rigid inner member surrounded by a flexible outer member.

16. The annuloplasty ring of claim 15, wherein the flexible outer member of each ring segment at least partly comprises a continuous fabric covering surrounding all of the ring segments.

17. The annuloplasty ring of claim 15, wherein the flexible outer member of each ring segment at least partly comprises a continuous flexible sheath closely surrounding all of the ring segments.

18. The annuloplasty ring of claim 17, wherein the ring segments are separated within the sheath to define voids therebetween.

19. The annuloplasty ring of claim 18, wherein the sheath is constricted into the voids.

20. The annuloplasty ring of claim 19, wherein sutures are used to constrict the sheath into the voids.

21. The annuloplasty ring of claim 15, wherein the inner members comprise titanium rods.

22. The annuloplasty ring of claim 1, further including:

cooperating structure formed on the ring segments preventing contraction of the ring and allowing expansion thereof; and

a fabric covering surrounding the ring segments to enable attachment to the annulus.

23. The annuloplasty ring of claim 22, wherein each ring segment has two free ends, the ring segments being arranged end to end to define the ring periphery, and further including a plurality of separate coupling members joining adjacent free ends of the ring segments to allow ring expansion but prevent ring contraction in conjunction with the cooperating structure formed on the free ends of the ring segments.

24. The annuloplasty ring of claim 23, wherein at least one of the coupling members is straight and positioned generally between commissures of the ring.

25. The annuloplasty ring of claim 22, wherein some of the ring segments have ends with inner channels, and some of the ring segments have ends with solid cross-sections for telescopically inserting in the inner channels of the ring segments.

26. The annuloplasty ring of claim 25, wherein the ring segments having ends with solid cross-sections include raised protrusions and the ring segments having ends with inner channels include detents, the cooperating structure being formed by an interference between the protrusions and the detents.

27. The annuloplasty ring of claim 22, further including a plurality of separate coupling members joining the ring segments to allow ring expansion but prevent ring contraction in conjunction with the cooperating structure formed on the ring segments.

28. The annuloplasty ring of claim 27, wherein the coupling members include raised protrusions and the ring segments include detents, the cooperating structure being formed by an interference between the protrusions and the detents.

29. The annuloplasty ring of claim 22, wherein the cooperating structure includes mating protrusions and detents, wherein expansion and contraction of the ring is regulated by an interference between the protrusions and the detents.

30. The annuloplasty ring of claim 29, wherein the cooperating structure includes a series of mating protrusions and detents, wherein the ring may be incrementally expanded and prevented from contracting therefrom at least two times.

31. The annuloplasty ring of claim 1, further comprising:

cooperating structure formed on the ring segments preventing contraction of the ring and allowing incremental expansion thereof, the cooperating structure configured to allow expansion from a first ring size to a second ring size upon application of a first expansion force and from the second ring size to a third ring size upon application of a second expansion force different in magnitude than the first expansion force; and

a fabric covering surrounding the ring segments to enable attachment to the annulus.

32. The annuloplasty ring of claim 31, wherein each ring segment has two free ends, the ring segments being arranged end to end to define the ring periphery, and further including a plurality of separate coupling members joining adjacent free ends of the ring segments to allow ring expansion but prevent ring contraction in conjunction with the cooperating structure formed on the free ends of the ring segments.

33. The annuloplasty ring of claim 32, wherein at least one of the coupling members is straight and positioned generally between commissures of the ring.

34. The annuloplasty ring of claim 31, wherein some of the ring segments have ends with inner channels, and some of the ring segments have ends with solid cross-sections for telescopically inserting in the inner channels of the ring segments.

35. The annuloplasty ring of claim 34, wherein the ring segments having ends with solid cross-sections include raised protrusions and the ring segments having ends with inner channels include detents, the cooperating structure being formed by an interference between the protrusions and the detents.

36. The annuloplasty ring of claim 31, further including a plurality of separate coupling members joining the ring segments to allow ring expansion but prevent ring contraction in conjunction with the cooperating structure formed on the ring segments.

37. The annuloplasty ring of claim 36, wherein the coupling members include raised protrusions and the ring segments include detents, the cooperating structure being formed by an interference between the protrusions and the detents.

38. The annuloplasty ring of claim 31, wherein the cooperating structure includes a plurality of mating protrusions and detents, wherein the magnitudes of the first and second expansion forces are determined by an interference between the protrusions and the detents.

39. The annuloplasty ring of claim 38, wherein some of the mating protrusions are differently sized from others to regulate the first and second expansion forces.

40. The annuloplasty ring of claim 39, the magnitude of the first expansion force is less than the magnitude of the second expansion force.

41. The annuloplasty ring of claim 1, further comprising:

a plurality of coupling tubes having inner channels for receiving free ends of the ring segments at interfaces to together define the ring periphery;

a radially expandable fabric covering surrounding the ring segments and coupling tubes to enable attachment to the annulus;

wherein each ring segment/coupling tube interface includes;

at least two protrusions formed on one of the ring segment or coupling tube; and

at least two detents formed on the other of the ring segment or coupling tube for mating with the protrusions, wherein the ring is expandable from an initial size to a first enlarged size upon application of a first enlarging force and the ring is expandable from the first enlarged size to a second enlarged size upon application of a second enlarging force different than the first enlarging force.

42. The annuloplasty ring of claim 41, wherein the protrusions are formed in series on the ends of the ring segments.

43. The annuloplasty ring of claim 42, wherein there are at least two protrusions of differing sizes.

44. The annuloplasty ring of claim 42, wherein there are at least two protrusions of differing shapes.

45. The annuloplasty ring of claim 42, wherein the protrusions include a face angle facing toward each detent, and wherein the first and second enlarging forces are determined by the magnitude of the face angles.

46. The annuloplasty ring of claim 41, wherein the ring segments each comprise an inner stiffening portion and an exterior polymeric portion.

47. The annuloplasty ring of claim 46, wherein the inner stiffening portion is metallic.

48. The annuloplasty ring of claim 46, wherein the inner stiffening portion is offset from a central axis of the ring segment away from the protrusions.

49. The annuloplasty ring of claim 41, wherein the first enlarging force is less than the second enlarging force.

50. The annuloplasty ring of claim 41, wherein the coupling tubes include a series of apertures separated by bridges, the apertures defining the detents and the bridges being formed to interfere with the protrusions formed on the ring segments.

51. The annuloplasty ring of claim 50, wherein the coupling tubes are tubular in cross-section and the bridges are flattened chords of the tube.

52. The annuloplasty ring of claim 51, wherein the protrusions are formed as ramps with angled faces toward the bridges.

53. The annuloplasty ring of claim 52, wherein there are at least two protrusions of differing radial heights.

54. The annuloplasty ring of claim 52, wherein there are at least two protrusions of differing axial thicknesses.

55. The annuloplasty ring of claim 52, wherein the angles facing toward each bridge on two of the protrusions are of different magnitude.

56. The annuloplasty ring of claim 41, wherein the ring segments comprise a polyacetal, and the coupling tubes comprise a metal.

57. An expandable annuloplasty ring shaped to support a mitral heart valve annulus, comprising:

a plurality of relatively rigid ring segments coupled end-to end to pivot with respect to one another and defining a generally defining a D-shape periphery with a straight side and a convex side, wherein there are four ring segments and three end-to-end pivoting couples and the periphery includes a discontinuity located between two of the ring segments in the midpoint of the straight side of the periphery, the ring segments being coupled together to be relatively movable with respect to one another so that the ring may be expanded to accommodate growth of the annulus.

58. The annuloplasty ring of claim 57, wherein the two ring segments on either side of the discontinuity are substantially shorter than the other two ring segments and relatively straight to generally define the straight side of the periphery.

59. An expandable annuloplasty ring for implantation in a heart valve annulus, comprising:

a plurality of relatively rigid ring segments coupled end-to end to pivot with respect to one another and defining a periphery of the ring having a discontinuity between two of the ring segments, the ring segments each comprising a rigid inner member surrounded by a flexible outer member, the flexible outer member of each ring segment at least partly comprising a continuous flexible sheath closely surrounding all of the ring segments, wherein the ring segments are separated within the sheath to define voids therebetween and a soft filler material is provided in the voids between the ring segments and within the sheath, the ring segments being coupled together to be relatively movable with respect to one another so that the ring may be expanded to accommodate growth of the annulus.

60. The annuloplasty ring of claim 59, wherein the filler material is silicone.

61. The annuloplasty ring of claim 59, wherein there are at least three ring segments and two end-to-end pivoting couples.

62. The annuloplasty ring of claim 59, wherein the annuloplasty ring is shaped to support a mitral annulus, the periphery generally being formed in a D-shape with a straight side and a convex side.

63. The annuloplasty ring of claim 62, wherein there are three ring segments and two end-to-end pivoting couples, and the discontinuity is located between two of the ring segments in the midpoint of the convex side of the periphery.

64. The annuloplasty ring of claim 63, wherein a first one of the ring segments extends substantially the length of the straight side of the D-shaped periphery, with the two other ring segments being pivotally connected to the first ring segment.

65. The annuloplasty ring of claim 59, wherein the flexible outer sheath comprises a continuous fabric covering.

66. The annuloplasty ring of claim 59, wherein the sheath is constricted into the voids.

67. The annuloplasty ring of claim 66, wherein sutures are used to constrict the sheath into the voids.