Intravascular stent with increasing coating retaining capacity

• US 20040225347A1
• Filed: 07/18/2003
• Published: 11/11/2004
• Est. Priority Date: 06/05/2000
• Status: Abandoned Application

• Current Assignee: Boston Scientific Scimed, Inc. (Boston Scientific Corporation)
• Original Assignee: Boston Scientific Scimed, Inc. (Boston Scientific Corporation)
• Inventors: Lang, G. David
• Application Number:
  US10/297,372
• Publication Number:
  US 20040225347A1
• Time in Patent Office: Days
• US Class Current: 623/1.15
• CPC Class Codes: A61F 2/91 made from perforated sheet material or tubes, e.g. perforated by laser cuts or etched holes
• CPC Class Codes: A61F 2/915 with bands having a meander structure, adjacent bands being connected to each other
• CPC Class Codes: A61F 2002/91525 within the whole structure different bands showing different meander characteristics, e.g. frequency or amplitude
• CPC Class Codes: A61F 2002/91533 characterised by the phase between adjacent bands
• CPC Class Codes: A61F 2002/91558 connected peak to peak
• CPC Class Codes: A61F 2250/0068 the pharmaceutical product being in a reservoir

Abstract

An expandable stent includes a tubular structure with an outer surface positionable adjacent to a vessel wall and an inner surface facing a lumen of a body passageway. The tubular structure further includes a plurality of expansion struts, connector struts and cells. The tubular structure has a first diameter which permits intraluminal delivery of the tubular structure into the body passageway, and a second expanded and deformed diameter which is achieved upon the application of a radially, outwardly extending force. A plurality of cavities are formed in the outer surface of the stent.

Claims

1. An expandable stent, comprising:

a tubular structure including an outer surface positionable adjacent to a vessel wall, an inner surface facing a lumen of a body passageway, a plurality of expansion struts, connector struts and cells, the tubular structure having a first diameter which permits intraluminal delivery of the tubular structure into the body passageway having a lumen, and a second expanded and deformed diameter upon the application from the interior of the tubular member of a radially, outwardly extending force; and

a plurality of cavities formed in the outer surface of the stent.

2. The stent of claim 1, wherein the tubular structure is balloon expandable.

3. The stent of claim 1, wherein the tubular structure is self-expandable.

4. The stent of claim 1, wherein at least a portion of the tubular structure is made of a shape memory alloy.

5. The stent of claim 1, wherein the plurality of cavities are substantially evenly positioned on the tubular structure.

6. The stent of claim 1 wherein the plurality of cavities increase a flexibility of the stent without substantially reducing a radial strength of the stent in a deployed state.

7. The stent of claim 1, wherein the plurality of cavities are micro-holes that extend from the outer surface.

8. The stent of claim 7, wherein the micro-holes have a cross-section that is smaller than a cross section of a strut.

9. The stent of claim 7, wherein the micro-holes extend from the outer surface through the inner surface.

10. The stent of claim 7, wherein the micro-holes extend from the outer surface to an interior of the tubular structure without extending through the inner surface.

11. The stent of claim 7, wherein at least a portion of the micro-holes extend from the outer surface through the inner surface and at least a portion extend from the outer surface to an interior of the tubular structure without extending through the inner surface.

12. The stent of claim 7, wherein at least a portion of the micro-holes have geometry'"'"'s that are configured to provide a reservoir for a coating substance applied to the tubular structure.

13. The stent of claim 7, wherein at least a portion of the micro-holes have a diameter of at least 0.0007 inch.

14. The stent of claim 7, wherein at least a portion of the micro-holes extend perpendicular from the outer surface to an interior of the tubular structure.

15. The stent of claim 7, wherein at least a portion of the micro-holes extend at a non-perpendicular slant angle from the outer surface to an interior of the tubular structure.

16. The stent of claim 1, wherein the plurality of cavities are micro-slits that extend from the outer surface.

17. The stent of claim 16, wherein the micro-slits have a cross-section that is smaller than a cross section of a strut.

18. The stent of claim 16, wherein the micro-slits extend from the outer surface through the inner surface.

19. The stent of claim 16, wherein the micro-slits extend from the outer surface to an interior of the tubular structure without extending through the inner surface.

20. The stent of claim 16, wherein at least a portion of the micro-slits extend from the outer surface through the inner surface and at least a portion extend from the outer surface to an interior of the tubular structure without extending through the inner surface

21. The stent of claim 16, wherein at least a portion of the micro-slits have geometry'"'"'s that are configured to provide a reservoir for a coating substance applied to the tubular structure.

22. The stent of claim 16, wherein at least a portion of the micro-slits have a width of at least 0.0007 inch.

23. The stent of claim 16, wherein at least a portion of the micro slits have a width greater than 0.0007 inch.

24. The stent of claim 16, wherein at least a portion of the micro slits have a length of at least 0.001 inch.

25. The stent of claim 16, wherein at least a portion of the micro slits have a length greater than 0.001 inch.

26. The stent of claim 16, wherein at least a portion of the micro-slits extend perpendicular from the outer surface to an interior of the tubular structure.

27. The stent of claim 16, wherein at least a portion of the micro-slits extend at a non-perpendicular slant angle from the outer surface to an interior of the tubular structure.

28. The stent of claim 16, wherein at least a portion of the micro-slits have a linear geometric shape.

29. The stent of claim 16, wherein at least a portion of the micro-slits have a curved geometric shape.

30. The stent of claim 16, wherein at least a portion of the micro-slits have a bottom surface formed in an interior of the tubular structure.

31. The stent of claim 30, further including at least one aperture that extends from the bottom surface of a micro-slit through the inner surface.

32. The stent of claim 30, further including a plurality of apertures that extend from the bottom surface of the micro-slit through the inner surface.

33. The stent of claim 1, further comprising:

a coating substance on at least a portion of outer surface of the stent including at least a portion of the plurality of cavities.

34. The stent of claim 33, wherein the coating substance is a restenosis inhibiting agent.

35. The stent of claim 34, wherein the restenonis inhibiting agent is selected from a drug, polymer and bio-engineered material.

36. The stent of claim 34, wherein the restenonis inhibiting agent is a combination of two agents selected from a drug, polymer and bio-engineered material.

37. The stent of claim 34, wherein each of a cavity of the plurality of cavities is configured to have a shape adapted to increase an amount of restenosis inhibiting agent coated on the stent.

38. The stent of claim 33, wherein each of a cavity of the plurality of cavities is configured to have a shape adapted to provide reservoir of the coated substance on the stent.

43. The stent of claim 34, wherein the restenonis inhibiting agent is a combination of two agents selected from a drug, polymer and bio-engineered material.

39. An expandable stent, comprising:

a tubular structure including an outer surface positionable adjacent to a vessel wall, an inner surface facing a lumen of a body passageway, a plurality of expansion struts, connector struts and cells, the tubular structure having a first diameter which permits intraluminal delivery of the tubular structure into the body passageway having a lumen, and a second expanded and deformed diameter upon the application from the interior of the tubular member of a radially, outwardly extending force;

a plurality of cavities formed in the outer surface of the stent; and

a coating substance on at least a portion of outer surface of the stent including and extending into at least a portion of the cavities.

40. The stent of claim 39, wherein the coating substance is on at least a portion of the inner surface of the stent.

41. The stent of claim 39, wherein the coating substance is a restenosis inhibiting agent.

42. The stent of claim 41, wherein the restenonis inhibiting agent is selected from a drug, polymer and bio-engineered material.

44. The stent of claim 40, wherein each of a cavity of the plurality of cavities is configured to have a shape adapted to increase an amount of restenosis inhibiting agent coated on the stent.

45. The stent of claim 39, wherein each of a cavity of the plurality of cavities is configured to have a shape adapted to provide a reservoir of the coated substance on the stent.

46. The stent of claim 39, wherein the tubular structure is balloon expandable.

47. The stent of claim 39, wherein the tubular structure is self-expandable.

48. The stent of claim 39, wherein at least a portion of the tubular structure is made of a shape memory alloy.

49. The stent of claim 39, wherein the plurality of cavities are substantially evenly positioned on the tubular structure.

50. The stent of claim 39, wherein the plurality of cavities increase a flexibility of the stent without substantially reducing a radial strength of the stent in a deployed state.

51. The stent of claim 39, wherein the plurality of cavities are micro-holes that extend from the outer surface.

52. The stent of claim 51, wherein the micro-holes have a cross-section that is smaller than a cross section of a strut.

53. The stent of claim 39, wherein the plurality of cavities are micro-slits that extend from the outer surface.

55. A stent assembly, comprising:

a balloon; and

an expandable stent positioned at an exterior of the balloon, the stent including,

a tubular structure including an outer surface positionable adjacent to a vessel wall, an inner surface facing a lumen of a body passageway, a plurality of expansion struts, connector struts and cells, the tubular structure having a first diameter which permits intraluminal delivery of the tubular structure into the body passageway having a lumen, and a second expanded and deformed diameter upon the application from the interior of the tubular member of a radially, outwardly extending force applied by the balloon;

a plurality of cavities formed in the outer surface of the stent; and

a coating substance on at least a portion of outer surface of the stent including and extending into at least a portion of the cavities.

54. The stent of claim 55, wherein the micro-slits have a cross-section that is smaller than a cross section of a strut.

56. The stent of claim 55, wherein the coating substance is on at least a portion of the inner surface of the stent.

57. The stent of claim 55, wherein the coating substance is a restenosis inhibiting agent.

58. The stent of claim 55, wherein the restenonis inhibiting agent is selected from a drug, polymer and bio-engineered material.

59. The stent of claim 55, wherein each of a cavity of the plurality of cavities is configured to have a shape adapted to increase an amount of restenosis inhibiting agent coated on the stent.

60. The stent of claim 55, wherein each of a cavity of the plurality of cavities is configured to have a shape adapted to provide a reservoir of the coated substance on the stent.

61. A method of manufacturing an intravascular stent, comprising:

forming an intravascular stent having an inner surface and an outer surface; and

forming a plurality of cavities on the outer surface of the intravascular stent; and

disposing on at least a portion of the outer surface and at least a portion of the plurality of cavities a coating substance that inhibits restenosis.

62. The method of claim 61, wherein at least a portion of the plurality of cavities is formed on the outer surface of the intravascular stent by a laser.

63. The method of claim 61, wherein the at least a portion of the plurality of cavities is formed on the outer surface of the intravascular stent by EDM.

64. The method of claim 61, wherein the at least a portion of the plurality of cavities is photochemically formed on the outer surface of the intravascular stent.