Adjustable annuloplasty ring activation system

• US 20070135913A1
• Filed: 12/14/2006
• Published: 06/14/2007
• Est. Priority Date: 06/29/2004
• Status: Abandoned Application

• Current Assignee: MiCardia Corporation
• Original Assignee: MiCardia Corporation
• Inventors: Lenker, Jay, Shaolian, Samuel, Moaddeb, Shawn, Sawicz, Conrad, Dabney, James
• Application Number:
  US11/638,501
• Publication Number:
  US 20070135913A1
• Time in Patent Office: Days
• US Class Current: 623/2.370
• CPC Class Codes: A61F 2/2445 Annuloplasty rings in direct contact with the valve annulus
• CPC Class Codes: A61F 2/2448 D-shaped rings
• CPC Class Codes: A61F 2210/0038 electromagnetically
• CPC Class Codes: A61F 2210/009 magnetic
• CPC Class Codes: A61F 2250/0001 Means for transferring electromagnetic energy to implants
• CPC Class Codes: A61F 2250/0004 adjustable

Abstract

An adjustable annuloplasty device is described. The device includes a body member comprising a shape memory material, the body member configured to be placed at or near a base of a valve of a heart. The device further includes a hysteretic material configured to undergo magnetic hysteresis in response to a first activation energy, the hysteretic material being in thermal communication with the shape memory material. The body member may have a first size of a body member dimension in a first configuration and a second size of the body member dimension in a second configuration. When the body member is in position in the heart, a change from the first configuration to the second configuration changes a size of a dimension of the annulus of the valve.

Claims

1. An adjustable annuloplasty device, comprising:

a body member comprising a shape memory material, the body member configured to be placed at or near a base of a valve of a heart;

a hysteretic material configured to undergo magnetic hysteresis in response to a first activation energy, the hysteretic material being in thermal communication with the shape memory material;

wherein the body member has a first size of a body member dimension in a first configuration and a second size of the body member dimension in a second configuration; and

wherein, when the body member is in position in the heart, a change from the first configuration to the second configuration changes a size of a dimension of an annulus of the valve.

2. The adjustable annuloplasty device of claim 1, wherein the change from the first configuration to the second configuration occurs in response to heating of the shape memory material.

3. The adjustable annuloplasty device of claim 1, wherein the first activation energy comprises a magnetic field.

4. The adjustable annuloplasty device of claim 3, wherein the magnetic field comprises a time varying magnetic field.

5. The adjustable annuloplasty device of claim 1, wherein the hysteretic material coats the body member.

6. The adjustable annuloplasty device of claim 5, wherein the hysteretic material coating the body member has a thickness between about 10 microns to about 1 centimeter.

7. The adjustable annuloplasty device of claim 1, wherein the hysteretic material is alloyed with the shape memory material.

8. The adjustable annuloplasty device of Claim 1, wherein the hysteretic material is further configured to heat in response to the first activation energy.

9. The adjustable annuloplasty device of claim 8, wherein the heat is due to electromagnetic induction heating.

10. The adjustable annuloplasty device of claim 1, wherein the hysteretic material is configured to transfer heat to the shape memory material.

11. The adjustable annuloplasty device of claim 1, wherein the shape memory material comprises at least one of a metal, a metal alloy, a nickel titanium alloy, a shape memory polymer, polylactic acid, and polyglycolic acid.

12. The adjustable annuloplasty device of claim 1, wherein the hysteretic material comprises a ferromagnetic material.

13. The adjustable annuloplasty device of claim 1, further comprising a suturable material configured to facilitate attachment of the body member to the cardiac valve annulus.

14. The adjustable annuloplasty device of claim 1, wherein the body member has a third size of the body member dimension in a third configuration, wherein the third size is larger than the second size, and wherein the body member is configured to transform to the third configuration in response to a second activation energy to increase the dimension of the cardiac valve annulus.

15. The adjustable annuloplasty device of claim 1, wherein the body member has a third size of the body member dimension in a third configuration, wherein the third size is smaller than the second size, and wherein the body member is configured to transform to the third configuration in response to a second activation energy to decrease the dimension of the cardiac valve annulus.

16. The adjustable annuloplasty device of claim 1, wherein the hysteretic material comprises a nanoparticle.

17. The adjustable annuloplasty device of claim 16, wherein the nanoparticle comprises at least one of a nanoshell and a nanosphere.

18. The adjustable annuloplasty device of claim 1, wherein the hysteretic material is radiopaque.

19. The device of claim 1, wherein the hysteretic material is ferromagnetic.

20. The device of claim 1, wherein the hysteretic material has a curie point in the range of 40 to 70 degrees Celsius.

21. The device of claim 1, wherein the hysteretic material has a curie point in the range of 45 to 55 degrees celsius.

22. A method, for adjusting the shape of an implant, comprising:

providing an adjustable annuloplasty device, comprising;

(i) a body member comprising a shape memory material, the body member configured to be placed at or near a base of a valve of a heart;

(ii) a hysteretic material configured to undergo magnetic hysteresis in response to a first activation energy from a magnetic field, the hysteretic material being in thermal communication with the shape memory material;

(iii) wherein the body member has a first size of a body member dimension in a first configuration and a second size of the body member dimension in a second configuration; and

(iv) wherein, when the body member is in position in the heart, a change in the body member from the first configuration to the second configuration changes a size of a dimension of an annulus of the valve; and

exposing the device to the magnetic field, changing the body member from the first configuration to the second configuration.

23. The method of claim 22, wherein the change from the first configuration to the second configuration occurs in response to heating of the shape memory material.

24. The method of claim 22, wherein the magnetic field comprises a time varying magnetic field.

25. The method of claim 22, wherein the magnetic field is produced by an electromagnet driven with an alternating current.

26. The method of claim 24, wherein the alternating current is in the range of 0.001 Hz to 1000 MHz.

27. The method of claim 24, wherein the alternating current is in the range of 10 Hz to 100 KHz.

28. The method of claim 24, wherein the alternating current is in the range of 15 KHz to 25 KHz.

29. The method of claim 24, wherein the magnetic field is produced by an electromagnet driven with a modulated alternating current.

33. The method of claim 22, wherein the magnetic field is produced by a plurality of electromagnets driven with a modulated alternating current source with controlled phase relationships.

34. The method of claim 22, wherein the magnetic field is produced by a permanent magnet that is mechanically displaced back and forth by a mechanical driver.

35. The method of claim 34, wherein the mechanical displacement is oscillatory.

36. The method of claim 35, wherein the mechanical displacement is a resonant motion.

37. The method of claim 22, wherein the magnetic field is produced by an electromagnet that is mechanically displaced.

38. The method of claim 37, wherein the electromagnet is driven by a DC current.

39. The method of claim 37, wherein the mechanical displacement is oscillatory.

40. The method of claim 37, wherein the mechanical displacement is a resonant motion.

41. The method of claim 37, wherein the electromagnet is driven by an AC current.

42. The method of claim 22, wherein the magnetic field is produced by imposing at least one high frequency magnetic field on at least one low frequency magnetic field.

43. An annuloplasty system, comprising:

an adjustable annuloplasty device, comprising;

(v) a body member comprising a shape memory material, the body member configured to be placed at or near a base of a valve of a heart;

(vi) a hysteretic material configured to undergo magnetic hysteresis in response to a first activation energy from a magnetic field, the hysteretic material being in thermal communication with the shape memory material;

(vii) wherein the body member has a first size of a body member dimension in a first configuration and a second size of the body member dimension in a second configuration; and

(viii) wherein, when the body member is in position in the heart, a change in the body member from the first configuration to the second configuration changes a size of a dimension of an annulus of the valve; and

a magnet, configured to emanate the magnetic field.

30. The method of claim 49, wherein the modulated alternating current comprises amplitude modulation.

31. The method of claim 30, wherein the modulated alternating current comprises frequency modulation.

32. The method of claim 30, wherein the modulated alternating current comprises phase modulation.

44. The system of claim 43, wherein the change from the first configuration to the second configuration occurs in response to heating of the shape memory material.

45. The system of claim 43, wherein the magnetic field is produced by an electromagnet driven with an alternating current.

46. The system of claim 44, wherein the alternating current is in the range of 0.001 Hz to 1000 MHz.

47. The system of claim 44, wherein the alternating current is in the range of 10 Hz to 100 KHz.

48. The system of claim 44, wherein the alternating current is in the range of 15 KHz to 25 KHz.

49. The system of claim 43, wherein the magnetic field is produced by an electromagnet driven with a modulated alternating current.

50. The system of claim 49, wherein the modulated alternating current comprises amplitude modulation.

51. The system of claim 49, wherein the modulated alternating current comprises frequency modulation.

52. The system of claim 49, wherein the modulated alternating current comprises phase modulation.

53. The system of claim 43, wherein the magnetic field is produced by a plurality of electromagnets driven with a modulated alternating current source with controlled phase relationships.

54. The system of claim 43, wherein the magnetic field is produced by a permanent magnet that is mechanically displaced back and forth by a mechanical driver.

55. The system of claim 54, wherein the mechanical displacement is oscillatory.

56. The system of claim 55, wherein the mechanical displacement is a resonant motion.

57. The system of claim 43, wherein the magnetic field is produced by an electromagnet that is mechanically displaced.

58. The system of claim 57, wherein the electromagnet is driven by a DC current.

59. The system of claim 57, wherein the mechanical displacement is oscillatory.

60. The system of claim 57, wherein the mechanical displacement is a resonant motion.

61. The system of claim 57, wherein the electromagnet is driven by an AC current.

62. The system of claim 43, wherein the magnetic field is produced by imposing at least one high frequency magnetic field on at least one low frequency magnetic field.

63. The system of claim 43, further comprising a feedback system configured to provide regulation and control of at least one of the magnetic field intensity or the system temperature.

64. An adjustable annuloplasty device, comprising:

means for supporting a heart valve comprising a shape memory material, the means for supporting being configured to be placed at or near a base of a valve of a heart;

means for undergoing magnetic hysteresis in response to a first activation energy, the means for undergoing magnetic hysteresis being in thermal communication with the shape memory material;

wherein the means for supporting has a first size of a body member dimension in a first configuration and a second size of the body member dimension in a second configuration; and

wherein, when the means for supporting is in position in the heart, a change from the first configuration to the second configuration changes a size of a dimension of an annulus of the valve; and

means for exposing the device to the magnetic field, changing the body member from the first configuration to the second configuration.