Implantable medical device having protruding surface structures for drug delivery and cover attachment

• US 6,254,632 B1
• Filed: 09/28/2000
• Issued: 07/03/2001
• Est. Priority Date: 09/28/2000
• Status: Active Grant

• Current Assignee: Advanced Cardiovascular Systems Incorporated
• Original Assignee: Advanced Cardiovascular Systems Incorporated
• Inventors: Guruwaiya, Judy A., Wu, Steven Z., Sanders-Millare, Deborra, Harish, Sameer
• Primary Examiner(s): Recla, Henry J.
• Assistant Examiner(s): HO, TAN-UYEN THI
• Application Number:
  US09/675,044
• Time in Patent Office: 278 Days
• Field of Search: 623/1.13, 623/1.15, 623/1.16, 623/1.44, 623/1.34, 623/1.1, 623/1.42, 623/1.12, 623/1.11
• 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 2002/075 the stent being loosely attached to the graft material, e.g. by stitching
• CPC Class Codes: A61F 2002/91516 the meander having a change in frequency along the band
• CPC Class Codes: A61F 2002/91533 characterised by the phase between adjacent bands
• CPC Class Codes: A61F 2220/005 using adhesives
• CPC Class Codes: A61F 2230/0013 Horseshoe-shaped, e.g. crescent-shaped, C-shaped, U-shaped
• CPC Class Codes: A61F 2230/0054 V-shaped
• CPC Class Codes: A61F 2250/0068 the pharmaceutical product being in a reservoir

Abstract

A method for forming an implantable medical device, such as a stent, covered stent, or synthetic stent graft, is provided. Protruding structures are formed on a surface of the device. The protruding structures have a central depression region surrounded by a lip. The protruding structures can have a variety of shapes, including circular and ovular shapes, or the protruding structure can form a groove. The protruding structures can be used to engage a cover. Glue can be added to the protruding structures to help secure the cover. The protruding structures can also contain a therapeutic substance or substances for release in situ. The protruding structures can be formed using a laser discharge to create a hole in the stent surface followed by directing a pressurized stream of grit at the surface.

Claims

1. An implantable medical device comprising:

a substrate having a first surface, said first surface having a plurality of protruding structures, wherein each of said protruding structures includes

a depression region having a bottom surface, said depression region approximately centrally located in said protruding structure; and

a lip surrounding at least a portion of said depression region, said lip having a height that extends above said bottom surface and said first surface.

2. The implantable medical device of claim 1, wherein said depression region and lip are substantially circular.

3. The implantable medical device claim 1, wherein said depression region and lip form a groove.

4. The implantable medical device of claim 1, wherein said substrate has a thickness defined by a distance between said first surface and an opposite second surface, said protruding structure has a depth defined by a distance between said bottom surface and said first surface, and said depth is less than 80% of said thickness.

5. The implantable medical device of claim 1, wherein said bottom surface is above said first surface.

6. The implantable medical device of claim 1, wherein said bottom surface is beneath said first surface.

7. The implantable medical device of claim 1 further comprising:

a cover overlying said first surface, wherein said protruding structures engage said cover.

8. The implantable medical device of claim 7 further comprising glue located in said depression region of at least some of said protruding structures.

9. The implantable medical device of claim 7, wherein said cover comprises a therapeutic substance.

10. The stent of claim 1, wherein said depression region contains one or more therapeutic substances.

11. The stent of claim 10, wherein said one or more therapeutic substances is covered by a polymeric layer.

12. A stent comprising:

a body having a generally cylindrical shape and an outer surface, wherein said outer surface includes a plurality of protruding structures, wherein said protruding structures include;

a depression region having a bottom surface, said depression region approximately centrally located in said protruding structure; and

a lip surrounding at least a portion of said depression region, said lip having a height that extends above said bottom surface and said outer surface.

13. The stent of claim 12 further comprising:

a cover overlying said outer surface, wherein said protruding structures engage said cover.

14. The stent of claim 13, wherein said cover has a first end and an opposing second end, wherein said stent comprises a first section and a second section, and wherein said first section is attached to said first end of said cover and said second section is attached to said second end of said cover.

15. The stent of claim 13, further comprising glue located in said depression region of at least some of said protruding structures.

16. The stent of claim 13, wherein said cover comprises a therapeutic substance.

17. The stent of claim 12, wherein said depression region and said lip are substantially circular.

18. The stent of claim 17, wherein said depression region contains one or more therapeutic substances.

19. The stent of claim 18, wherein said one or more therapeutic substances is covered by a polymeric layer.

20. The stent of claim 12, wherein said depression region and said lip form a groove.

21. The stent of claim 20, wherein said groove contains one or more therapeutic substances.

22. The stent of claim 21, wherein said one or more therapeutic substances is covered by a polymeric layer.

23. The stent of claim 12, wherein said body has a thickness defined by a distance between said outer surface and an opposite inner surface, said protruding structure has a depth defined by a distance between said bottom surface and said outer surface, and said depth is less than 80% of said thickness.

24. The stent of claim 12, wherein said bottom surface is above said outer surface.

25. The stent of claim 24, wherein said depression region contains one or more therapeutic substances.

26. The stent of claim 25, wherein said one or more therapeutic substances is covered by a polymeric layer.

27. The stent of claim 12, wherein said bottom surface is beneath said outer surface.

28. The stent of claim 27, wherein said depression region contains one or more therapeutic substances.

29. The stent of claim 28, wherein said one or more therapeutic substances is covered by a polymeric layer.

30. The stent of claim 12, wherein said depression region contains one or more therapeutic substances.

31. The stent of claim 30, wherein said one or more therapeutic substances is covered by a polymeric layer.