Multi-section filamentary endoluminal stent

• US 20030149473A1
• Filed: 02/14/2003
• Published: 08/07/2003
• Est. Priority Date: 11/16/1999
• Status: Active Grant

• Current Assignee: Lifeshield Sciences LLC (Acacia Research Corporation)
• Original Assignee: Patrick A. Haverkost, Paul F. Chouinard
• Inventors: Chouinard, Paul F., Haverkost, Patrick A.
• Granted Patent: US 7,160,319 B2
• Time in Patent Office: Days
• US Class Current: 623/1.15
• CPC Class Codes: A61F 2/07 Stent-grafts
• CPC Class Codes: A61F 2/90 characterised by a net-like or mesh-like structure
• 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 2002/065 Y-shaped blood vessels
• CPC Class Codes: A61F 2002/067 modular
• CPC Class Codes: A61F 2002/825 having longitudinal struts
• 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 2002/91541 Adjacent bands are arranged out of phase
• CPC Class Codes: A61F 2002/91558 connected peak to peak
• CPC Class Codes: A61F 2220/0008 Fixation appliances for connecting prostheses to the body
• CPC Class Codes: A61F 2220/005 using adhesives
• CPC Class Codes: A61F 2220/0058 soldered or brazed or welded
• CPC Class Codes: A61F 2220/0066 stapled
• CPC Class Codes: A61F 2220/0075 sutured, ligatured or stitched, retained or tied with a rope, string, thread, wire or cable
• CPC Class Codes: A61F 2230/0054 V-shaped
• CPC Class Codes: A61F 2250/0018 differing in elasticity, stiffness or compressibility
• CPC Class Codes: A61F 2250/0028 differing in fibre orientations
• CPC Class Codes: A61F 2250/0029 differing in bending or flexure capacity
• CPC Class Codes: D04C 1/06 Braid or lace serving particular purposes
• CPC Class Codes: D10B 2509/06 : Vascular grafts; stents

Abstract

A multi-section filamentary stent comprises a braided section, which is a cylindrical mesh of a first set of filaments, connected to at least one wound section comprising a second set of one or more filaments having a repeating configuration with a bent portion. The two sections are preferably connected by at least one continuous filament extending into both sections. The two sections may be connected by a weld, a suture, a common graft, an overlapping portion of the two sections, or one or more filaments of one section looping through portions of the other section. The stent may comprise a first section, having a braided first stent architecture with a first flexibility and a first radial force, and a second section, having a non-braided second stent architecture with a second flexibility less than the first flexibility and a second radial force greater than the first radial force, in which at least one continuous filament is integral to both the first and second sections. The stent may have a radially compressed configuration and a radially expanded configuration, in which the first section has a first shortening ratio, and the second section has a second shortening ratio less than the first shortening ratio. Such multi-section stents may comprise modular components of a modular stent, such as a bifurcated modular stent, adapted for joining together in situ. The multi-section stent may comprise a first section having a first percentage of open area and a second section having a second percentage of open area. The stent may also comprise a first section having a first stent architecture with an end effect wherein the radial strength at the end is less than elsewhere in the stent, and a second section having a second stent architecture to counteract the end effect. Methods for treating body lumen by implanting the stents as described herein are also disclosed, as is a method for counteracting a stent architecture end effect.

Claims

1. A multi-section stent comprising at least one braided section, which comprises a cylindrical mesh of a first set of filaments, and at least one wound section, which is connected to said braided section and comprises a second set of one or more filaments in a repeating configuration having at least one bent portion.

2. The stent of claim 1 wherein the filaments comprise metallic wire filaments.

3. The stent of claim 1 wherein the repeating configuration of the second set of filaments in the wound section defines:

a zig-zag configuration, an overlapping zig-zag configuration, a helical configuration, a non-helical configuration, or a configuration having polygonal cells.

4. The stent of claim 3 wherein the repeating configuration of the second set of filaments in the wound section defines hexagonal cells or overlapping hexagonal cells.

5. The stent of claim 1 wherein at least one continuous filament is a member of both the first set of filaments in the braided section and the second set of filaments in the wound section for connecting the braided section and the wound section.

6. The stent of claim 1 wherein at least one continuous filament extends into both the wound section and the braided section.

7. The stent of claim 6 wherein said at least one continuous filament which extends into both the wound section and the braided section comprises one of:

a redundant filament, a tracer filament, or a redundant tracer filament.

8. The stent of claim 1 wherein the braided section is connected to the wound section by one of:

sutures or welding.

9. The stent of claim 1 further comprising biocompatible graft material attached to the stent as an outer covering, an inner liner, or a combination thereof.

10. The stent of claim 9 wherein the graft comprises the only connection between the braided section and the wound section.

11. The stent of claim 1 wherein the wound section comprises a plurality of apices and one or more filaments of the braided section are looped around the apices to connect the wound and braided sections.

12. The stent of claim 1 wherein the wound section comprises a plurality of apices and the braided section comprises at least one overlap at which two of the filaments of the braided section cross over one another and wherein at least one filament of the wound section is looped around said at least one overlap to connect the wound and braided sections.

13. The stent of claim 1 wherein at least a portion of the wound section overlaps and interlocks with a portion of the braided section.

14. The stent of claim 1 wherein said at least one wound section comprises a first wound end section connected to a first end of said braided section and a second wound end section second connected to a second end of said braided section.

50. A method of treating a body lumen comprising implanting a multi-section filamentary stent according to claim 1.

51. The method of claim 50 wherein the braided section comprises a middle section of the stent, at least one of the wound sections comprises an end section, and wherein the body lumen has a fluid flow therein that traverses the stent from an upstream end to a downstream end, the method further comprising implanting the stent such that the upstream end comprises one of the wound sections.

52. The method of claim 50 wherein the body lumen has at least one tortuous region therein, the method further comprising implanting the stent such that at least one braided section is aligned with the tortuous region.

53. The method of claim 50 wherein the stent has a radially compressed configuration and a radially expanded configuration, and in which both the braided section and the wound section comprise architectures having substantially no degree of twist between the compressed and expanded configurations, the method further comprising introducing the stent into the body lumen in the compressed configuration and expanding the stent from the compressed configuration to the expanded configuration to implant the stent in the body lumen without the stent substantially twisting during expansion.

15. A multi-section filamentary stent comprising:

a first section, having a first stent architecture comprising one or more filaments in a first geometric configuration, the first stent architecture having a first flexibility and a first radial force, and

a second section, having a second stent architecture comprising one or more filaments in a second geometric configuration, the second stent architecture having a second flexibility less than the first flexibility and a second radial strength greater than the first radial strength;

wherein the stent comprises at least one continuous filament contained in both the first and second sections and the first stent architecture comprises a braided stent architecture.

16. The stent of claim 15 wherein the first section is disposed as a middle section between a first of said second sections disposed as a distal end section and a second of said second sections disposed as a proximal end section.

17. The stent of claim 16 wherein the distal end section and the proximal end section are identical in length.

18. The stent of claim 15 further comprising a third section connected to the first section, having a third stent architecture with a third flexibility less than the first flexibility and greater than the second flexibility and a third radial force greater than the first radial force and less than the second radial force, the stent comprising at least one continuous filament contained in both the first and third sections.

19. The stent of claim 18 further comprising at least one continuous filament contained in the first, the second, and the third sections.

20. The stent of claim 15 wherein each filament of the stent is a continuous filament extending through both the first and second sections.

21. The stent of claim 15 wherein the second stent architecture comprises one or more of:

a zig-zag configuration, an overlapping zig-zag configuration, a helical configuration, a non-helical configuration, or a configuration having polygonal cells.

22. The stent of claim 21 wherein the second stent geometric configuration defines a plurality of polygonal cells having as sides thereof straight axially-extending portions joined together along a set of parallel segments, the parallel segments deviating from one another proximally and distally of each parallel segment into diagonal segments, such that each set of parallel segments and attached diagonal segments form a Y-shaped intersection, each Y-shaped intersection at an interface between the first section and the second section having diagonal segments that extend into the first section.

23. The stent of claim 22 wherein the second stent geometric configuration comprises an end winding comprising a zig-zag configuration.

24. The stent of claim 23 wherein the zig-zag configuration of the end winding comprises an overlapping zig-zag configuration.

25. The stent of claim 24 wherein the overlapping zig-zag configuration comprises sets of double filaments extending parallel to one another.

26. The stent of claim 24 wherein the overlapping zig-zag configuration comprises sets of double filaments intersecting one another.

27. The stent of claim 15 wherein the stent has a radially compressed configuration and a radially expanded configuration, and in which both the first stent architecture and the second stent architecture comprise architectures having substantially no degree of twist between the compressed and expanded configurations.

28. The stent of claim 15 wherein the stent has a radially compressed configuration and a radially expanded configuration, and is self-expandable from the radially compressed configuration to the radially expanded configuration by spring elasticity or by thermal or stress-induced return of a shape memory material.

29. The stent of claim 15 further comprising biocompatible graft material attached to the stent as an outer covering, an inner liner, or a combination thereof.

54. A method of treating a body lumen comprising implanting a multi-section filamentary stent according to claim 15.

55. The method of claim 54 wherein the stent first section comprises a middle section, the stent second section comprises an end section, and the body lumen has a fluid flow therein traversing the stent from an upstream end to a downstream end, the method further comprising implanting the stent such that the upstream end comprises the second section.

30. A multi-section stent having a radially compressed configuration and a radially expanded configuration, the stent comprising a first section having a first, braided stent architecture with a first shortening ratio, and a second section having a second, wound stent architecture with a second shortening ratio, the first shortening ratio being greater than the second shortening ratio, the stent comprising at least one continuous filament contained in both the first and second sections.

31. The stent of claim 30 wherein the first section is disposed as a middle section between two of said second sections disposed as end sections.

32. A modular stent comprising at least two modular components adapted to be joined together in situ:

a first modular component comprising a multi-section stent comprising a first section, having a first stent architecture and a first geometric configuration with a first flexibility and a first radial force, and a second section, having a second stent architecture and a second geometric configuration with a second flexibility less than the first flexibility and a second radial force greater than the first radial force, the first component comprising at least one continuous filament contained in both the first and second sections; and

a second modular component comprising a multi-section filamentary stent comprising a third section, having a third stent architecture and a third geometric configuration and a fourth section, having a fourth stent architecture in a fourth geometric configuration, the second component comprising at least one continuous filament contained in both the third and fourth sections.

33. The modular stent of claim 32 wherein the stent has a radially compressed configuration and a radially expanded configuration, the first stent architecture having a first shortening ratio, the second stent architecture having a second shortening ratio, the third stent architecture having a third shortening ratio, and the fourth stent architecture having a fourth shortening ratio.

34. The modular stent of claim 32 wherein the first and third stent architectures comprise braided stent architectures and the second and fourth stent architectures comprises wound stent architectures.

35. The modular stent of claim 34 wherein the third geometric configuration is similar to the first geometric configuration and the fourth geometric configuration is similar to the second geometric configuration.

36. The modular stent of claim 35 wherein the third stent architecture is identical to the first stent architecture and the fourth stent architecture is identical to the second stent architecture.

37. The modular stent of claim 36 wherein the first component and the second component each comprise a middle section having the first stent architecture positioned between two end sections each having the second stent architecture, and in which the first component is adapted to be fitted together with the second component such that one of the end sections of the first component interlocks inside one of the end sections of the second component.

38. The modular stent of claim 37 wherein the modular stent is a bifurcated stent wherein:

the first modular component comprises a trunk component comprising a trunk distal end section, a trunk proximal end section, and a trunk middle section connected between the trunk distal end section and the trunk proximal end section, the trunk proximal end section being bifurcated into two connection sockets; and

the second modular component comprises a leg component comprising a leg distal end section, a leg proximal end section, and a leg middle section connected between the leg distal end section and the leg proximal end section, the leg distal end section adapted to interlock inside one of the connection sockets of the trunk proximal end section;

wherein the trunk middle section and the leg middle section each comprise the first stent architecture, and the trunk distal end section, the trunk proximal end section, the leg distal end section, and the leg proximal end section each comprise the second stent architecture.

39. The modular stent of claim 32 wherein the modular stent is a bifurcated stent wherein:

the first modular component comprises a trunk component comprising a trunk distal end section, a trunk proximal end section, and a trunk middle section connected between the trunk distal end section and the trunk proximal end section, the trunk proximal end section being bifurcated into two connection sockets;

the second modular component comprises a leg component comprising a leg distal end section, a leg proximal end section, and a leg middle section connected between the leg distal end section and the leg proximal end section, the leg distal end section adapted to interlock inside one of the connection sockets of the trunk proximal end section.

40. The modular stent of claim 39 wherein the trunk middle section and the leg middle section each comprise braided stent architectures, and the trunk distal end section, the trunk proximal end section, the leg distal end section, and the leg proximal end section each comprise wound stent architectures.

41. The modular stent of claim 40 further comprising a third component adapted to interlock inside the other of the connection sockets of the trunk proximal end section.

42. The modular stent of claim 37 wherein the modular stent is a bifurcated stent comprising:

a trunk component comprising a trunk distal end section, a trunk middle section connected to the trunk distal end section, a trunk bifurcated section connected to the trunk middle section and branching into a contralateral socket and an integral leg transition, the integral leg transition connected to an integral leg middle section which is connected to an integral leg proximal end section; and

a modular leg component comprising a modular leg distal end section, a modular leg proximal end section, and a modular leg middle section connected between the modular leg distal end section and the modular leg proximal end section, the modular leg distal end section adapted to interlock inside the contralateral socket of the trunk bifurcated section;

wherein the trunk middle section, the integral leg middle section, and the modular leg middle section comprise the first stent architecture, and the trunk distal end section, the trunk bifurcated section, the integral leg proximal end section, the modular leg distal end section, and the modular leg proximal end section comprise the second stent architecture.

43. The modular stent of claim 32 wherein the modular stent is a bifurcated stent comprising:

a trunk component comprising a trunk distal end section, a trunk middle section connected to the trunk distal end section, a trunk bifurcated section connected to the trunk middle section and branching into a contralateral socket and an integral leg transition, the integral leg transition connected to an integral leg middle section which is connected to an integral leg proximal end section;

a modular leg component comprising a modular leg distal end section, a modular leg proximal end section, and a modular leg middle section connected between the modular leg distal end section and the modular leg proximal end section, the modular leg distal end section adapted to interlock inside the contralateral socket of the trunk bifurcated section.

44. A multi-section filamentary stent comprising:

a first section, having a first stent architecture comprising one or more filaments in a first geometric configuration, the first stent architecture having a first percentage of open area, and

a second section, having a second stent architecture comprising one or more filaments in a second geometric configuration, the second stent architecture having a second percentage of open area greater than the first percentage;

wherein the stent comprises at least one continuous filament contained in both the first and second sections and the first stent architecture comprises a braided stent architecture.

45. The stent of claim 44 wherein the second section is adapted for deployment in a second portion of the body lumen having one or more intersecting lumen connected thereto.

56. A method of treating a body lumen comprising implanting a multi-section filamentary stent according to claim 44.

57. The method of claim 56 further comprising implanting the stent with the first section implanted in a first portion of a body lumen having no intersecting lumen connected thereto and the second section deployed in a second portion of the body lumen having one or more intersecting lumen connected thereto.

58. The method of claim 57 comprising implanting the stent in an aorta with the second section bridging intersecting renal lumen.

46. A multi-section filamentary stent comprising:

a first section, having a first stent architecture comprising one or more filaments in a first geometric configuration, the first stent architecture having a first radial strength in a middle portion and a second, reduced radial strength along the ends; and

a second section, having a second stent architecture comprising one or more filaments in a second geometric configuration, the second stent architecture having a radial strength greater than the second radial strength;

wherein the second section comprises an end section connected to the first section to counteract the reduced radial strength of the ends of the first section.

47. The stent of claim 46 wherein second stent architecture has a radial strength substantially equal to the first radial strength.

48. The stent of claim 46 wherein the stent comprises at least one continuous filament contained in both the first section and the second section.

49. The stent of claim 48 wherein the first stent architecture comprises a braided stent architecture.

59. A method of counteracting an end effect marked by a reduction in radial strength along an end length of a first stent section having a first stent architecture comprising one or more filaments in a first geometric configuration and having a first radial strength except for a second, lesser radial strength in said end length, the method comprising connecting a second stent section having a second stent architecture comprising one or more filaments in a second geometric configuration, the second stent architecture having a radial strength greater than the second radial strength.

60. The method of claim 59 further comprising connecting a second stent section having a second stent architecture with a radial strength substantially equal to the first radial strength.

61. The method of claim 59 further comprising counteracting the end effect of a braided stent architecture in the first section by connecting a wound stent section as the second stent section.