CIRCUMFERENTIALLY NESTED EXPANDABLE DEVICE

• US 20080183275A1
• Filed: 01/26/2007
• Published: 07/31/2008
• Est. Priority Date: 01/26/2007
• Status: Active Grant

• Current Assignee: REVA Medical Inc.
• Original Assignee: REVA Medical Inc.
• Inventors: Padilla, Orlando, Morris, Andrew, Schmid, Eric
• Granted Patent: US 7,704,275 B2
• Time in Patent Office: Days
• US Class Current: 623/1.15
• CPC Class Codes: A61F 2/844 folded prior to deployment
• 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 2002/91558 connected peak to peak
• CPC Class Codes: A61F 2002/91591 Locking connectors, e.g. using male-female connections
• CPC Class Codes: A61F 2210/0076 multilayered, e.g. laminated structures
• CPC Class Codes: A61F 2250/0007 for adjusting length
• CPC Class Codes: B33Y 80/00 Products made by additive manufacturing

Abstract

Expandable medical implants for maintaining support of a body lumen are disclosed. These implants comprise a circumferentially nested, diametrically expandable, moveable vascular device for enlarging an occluded portion of a vessel. The device can be configured to allow for motion such as rotating, translating, and/or slide and lock. One advantage of the circumferentially nested stent is that it maintains the expanded size, without significant recoil.

Claims

1. A circumferentially nested stent being expandable from a collapsed state to an expanded state, the stent comprising a tubular member having longitudinal and circumferential axes, the tubular member comprising:

at least one linkage section being disposed along the longitudinal axis, the linkage section comprising;

at least one structural element being disposed along the circumferential axis of the tubular member, the structural element having first and second ends, the first end being positionable substantially circumferentially adjacent the second end when the stent is in the unexpanded state, the first end including at least one first protrusion and the second end including at least one second protrusion; and

at least one link element having first and second ends, the first end having a first cavity disposed therein and the second end having a second cavity disposed therein, the first and second cavities each being sized and configured to engage the respective ones of the first and second protrusions to provide at least one of rotation and translation of the protrusion within the cavity for facilitating expansion of the stent to the expanded state.

2. The stent of claim 1 wherein the linkage section includes a plurality of structural elements disposed with the first end of each structural element being positionable circumferentially adjacent to the second end of an adjacent structural element when the stent is in the unexpanded state, wherein a respective plurality of link elements engage the first and second protrusions of the first and second ends of the structural elements for facilitating expansion of the stent.

3. The stent of claim 2 wherein the plurality of structural elements are disposed substantially coplanar within the linkage section when the stent is in the collapsed state.

4. The stent of claim 1 wherein the tubular member comprises a plurality of linkage sections.

5. The stent of claim 4 further comprising at least one flexible section, the flexible section being disposed intermediate the linkage sections along the longitudinal axis of the tubular member for tubularly interconnecting the linkage sections.

6. The stent of claim 1 wherein the link element is configured as an elongate link element.

7. The stent of claim 1 wherein the first end of the structural element includes a pair of first protrusions and the second end includes a pair of second protrusions.

8. The stent of claim 1 wherein at least one of the first and second cavities of the link element is an aperture that passes through the respective one of the first and second ends of the link element.

9. The stent of claim 1 further comprising annularly-shaped female ratchet members being disposable within the first and second cavities of the link element, each female ratchet member having a central lumen and at least one internal tooth oriented radially inwardly to within the lumen, the lumen being sized and configured to receive the protrusion therein with the internal tooth engaging the protrusion for providing one-way rotation of the protrusion within the lumen such that the stent is not collapsible to the collapsed state upon being expanded to the expanded state.

10. The stent of claim 9 wherein the protrusion of the structural element is configured as a male ratchet member having at least one male ratchet tooth extending radially outwardly and being configured to engage the internal tooth of the female ratchet member for providing one-way rotation of the protrusion within the lumen such that the stent is not collapsible to the collapsed state upon being expanded to the expanded state.

11. The stent of claim 1 wherein at least one of the first and second cavities of the link element is a slot which translatably engages the protrusion, the slot being axially disposed in the link element.

12. The stent of claim 11 wherein the slot includes a plurality of teeth along at least one side thereof, the teeth being sized and configured to provide one-way translation of the protrusion within the slot such that the stent is not collapsible to the collapsed state upon being expanded to the expanded state.

13. The stent of claim 1 wherein the structural element comprises a ring element having a series of circumferentially-aligned protrusions disposed at at least one of first and second ends of the ring element.

14. The stent of claim 1 wherein the stent further comprises a material selected from the group consisting of metal and polymer.

15. The stent of claim 14 wherein the polymer comprises a bioresorbable polymer.

16. The stent of claim 14 wherein the polymer comprises a radiopaque bioresorbable polymer.

17. The stent of claim 14 wherein the polymer forms a coating on at least a portion of the stent.

18. The stent of claim 14 wherein the polymer coating further comprises a biocompatible, bioresorbable polymer adapted to promote a selected response.

19. The stent of claim 1 further comprising a layered material, the layered material comprising a bioresorbable polymer.

20. The stent of claim 1 wherein the stent is fabricated from at least two materials.

21. The stent of claim 20 wherein each of the two materials is one of a material that is stacked in the radial axis, a material that varies along the longitudinal axis, a mixed material, a fused material, a coated material, and a material that varies among structurally distinct elements.

22. The stent of claim 1 wherein the stent further comprises a therapeutic agent.

23. The stent of claim 1 further comprising a retractable sheath sized for enclosing the tubular member during delivery to a treatment site.

24. The stent of claim 1 further comprising a solid wall region.

25. The stent of claim 24 wherein said solid wall region further comprises an opening.

26. The stent of claim 1 further comprising a polymeric sheath.

27. The stent of claim 1 wherein the stent further comprises a coating adapted to alter a physical characteristic of the stent.

28. The stent of claim 27 wherein the coating is further adapted to form frangible bonds between the stent and a catheter, such that the stent is retained on the catheter until deployed.

29. A method for re-treatment of a body lumen, comprising the steps of:

deploying to a region of the body lumen a bioresorbable polymer stent;

allowing the stent to reside at the region for a period of time; and

administering a treatment to the region after the period of time.

30. A circumferentially nested rotary three-bar linkage stent being expandable from a collapsed state to an expanded state, the stent comprising a tubular member having longitudinal and circumferential axes, the tubular member comprising:

at least one linkage section being disposed along the circumferential axis, the linkage section comprising at least one three-bar structural element, the three-bar structural element comprising;

first and second stent block bodies each having first and second ends, the stent block bodies being disposed along the circumferential axis of the tubular member, the first stent block body having a first male member being disposed at the first end thereof, the second stent block body having a second male member being disposed at the second end thereof; and

a stent body link having first and second ends, the stent body link having first and second cavities disposed at the respective ones of the first and second ends thereof, the first and second cavities each being sized and configured to engage the respective ones of the first male member of the first stent block body and the second male member of the second stent block body to thereby interconnect the stent body link with the first and second stent block bodies;

wherein the first stent block body is positionable substantially circumferentially adjacent to the second stent block body when the stent is in the unexpanded state, the first stent block body being separable from the second stent block body upon rotation of the first and second male members within the respective ones of the first and second cavities to rotate the stent body link thereby expanding the stent to the expanded state.

31. The stent of claim 30 further comprising annularly-shaped female ratchet members being disposable within the first and second cavities of the stent body link, each female ratchet member having a central lumen and at least one internal tooth oriented radially inwardly to within the lumen, the lumen being sized and configured to receive the male member therein with the internal tooth engaging the male member for providing one-way rotation of the male member within the lumen such that the stent is not collapsible to the collapsed state upon being expanded to the expanded state.

32. The stent of claim 31 wherein the male member is configured as a male ratchet member having at least one male ratchet tooth extending radially outwardly and being configured to engage the internal tooth of the female ratchet member for providing one-way rotation of the male member within the lumen such that the stent is not collapsible to the collapsed state upon being expanded to the expanded state.

33. The stent of claim 30 wherein the stent block bodies are oriented substantially parallel with respect to the longitudinal axis.

34. A circumferentially nested rotary three-bar linkage stent being expandable from a collapsed state to an expanded state, the stent comprising a tubular member having longitudinal and circumferential axes, the tubular member comprising:

at least one linkage section being disposed along the circumferential axis, the linkage section comprising at least one three-bar structural element, the three-bar structural element comprising;

first and second stent block bodies each having first and second ends, the stent block bodies being disposed along the circumferential axis of the tubular member, the first stent block body having a first cavity being disposed at the first end thereof, the second stent block body having a second cavity being disposed at the second end thereof; and

a stent body link having first and second ends, the stent body link having first and second male members disposed at the respective ones of the first and second ends thereof, the first and second male members each being sized and configured to engage the respective ones of the first cavity of the first stent block body and the second cavity of the second stent block body to thereby interconnect the stent body link with the first and second stent block bodies;

wherein the first stent block body is positionable substantially circumferentially adjacent to the second stent block body when the stent is in the unexpanded state, the first stent block body being separable from the second stent block body upon rotation of the first and second male members within the respective ones of the first and second cavities to rotate the stent body link thereby expanding the stent to the expanded state.

35. A circumferentially nested rotary-slide three-bar linkage stent being expandable from a collapsed state to an expanded state, the stent comprising a tubular member having longitudinal and circumferential axes, the tubular member comprising:

at least one linkage section being disposed along the circumferential axis, the linkage section comprising at least one three-bar structural element, the three-bar structural element comprising;

first and second end bars each having first and second ends, the end bars being disposed along the circumferential axis of the tubular member, the first end bar including a slot being axially disposed therealong and extending intermediate the first and second ends thereof, the second end bar including a cavity disposed at the first end thereof; and

a third shared bar having first and second ends, the shared bar having first and second male members disposed at the respective ones of the first and second ends thereof, the first and second male members each being sized and configured to extend into the respective ones of the slot of the first end bar and the cavity of the second end bar to thereby interconnect the shared bar with the first and second end bars;

wherein the first end bar is positionable substantially circumferentially adjacent to the second end bar when the stent is in the unexpanded state, the first end bar being separable from the second end bar upon translation of the first male member within the slot and rotation of the second male member within the cavity to rotate and translate the shared bar thereby expanding the stent to the expanded state.

36. The stent of claim 35 wherein the slot of the first end bar includes a plurality of teeth along at least one side thereof, the teeth being sized and configured to provide one-way translation of the first male member within the slot such that the stent is not collapsible to the collapsed state upon being expanded to the expanded state.

37. The stent of claim 35 further comprising an annularly-shaped female ratchet member being disposable within the cavity of the second end bar, the female ratchet member having a central lumen and at least one internal tooth oriented radially inwardly to within the lumen, the lumen being sized and configured to receive the second male member therein with the internal tooth engaging the second male member for providing one-way rotation of the second male member within the lumen such that the stent is not collapsible to the collapsed state upon being expanded to the expanded state.

38. The stent of claim 37 wherein the second male member is configured as a male ratchet member having at least one male ratchet tooth extending radially outwardly and being configured to engage the internal tooth of the female ratchet member for providing one-way rotation of the second male member within the lumen such that the stent is not collapsible to the collapsed state upon being expanded to the expanded state.

39. The stent of claim 35 wherein the end bars are oriented substantially parallel with respect to the longitudinal axis.

40. The stent of claim 35 wherein the tubular member comprises a plurality of linkage sections.

41. The stent of claim 40 further comprising at least one flexible section interposed between consecutive linkage sections, the flexible section having first and second ends, the first end thereof being connectable to at least a portion of a first consecutive linkage section and the second end thereof being connectable to at least a portion of a second consecutive linkage section with the flexible section being interposed therebetween.

42. The stent of claim 41 wherein the first end of the flexible section is connectable to the first end bar of the first consecutive linkage section and the second end is connectable to the first end bar of the second consecutive linkage section.

43. A circumferentially nested rotary-slide three-bar linkage stent being expandable from a collapsed state to an expanded state, the stent comprising a tubular member having longitudinal and circumferential axes, the tubular member comprising:

at least one linkage section being disposed along the circumferential axis, the linkage section comprising at least one three-bar structural element, the three-bar structural element comprising;

first and second end bars each having first and second ends, the end bars being disposed along the circumferential axis of the tubular member, the first end bar including a slot being axially disposed therealong and extending intermediate the first and second ends thereof, the second end bar including a second male member disposed at the first end thereof; and

a third shared bar having first and second ends, the shared bar having a first male member and a cavity disposed at the respective ones of the first and second ends thereof, the first male member being sized and configured to extend into the slot of the first end bar, the cavity being sized and configured to engage the second male member of the second end bar to thereby interconnect the shared bar with the first and second end bars;

wherein the first end bar is positionable substantially circumferentially adjacent to the second end bar when the stent is in the unexpanded state, the first end bar being separable from the second end bar upon translation of the first male member within the slot and rotation of the second male member within the cavity to rotate and translate the shared bar thereby expanding the stent to the expanded state.

44. A circumferentially nested rotary-slide three-bar linkage stent being expandable from a collapsed state to an expanded state, the stent comprising a tubular member having longitudinal and circumferential axes, the tubular member comprising:

at least one linkage section being disposed along the circumferential axis, the linkage section comprising at least one three-bar structural element, the three-bar structural element comprising;

first and second end bars each having first and second ends, the end bars being disposed along the circumferential axis of the tubular member, the end bars each including a slot being axially disposed along the end bar and extending intermediate the first and second ends thereof; and

a third shared bar having first and second ends, the shared bar having first and second male members disposed at the respective ones of the first and second ends thereof, the first and second male members each being sized and configured to extend into the slots of the respective ones of the first and second end bars to thereby interconnect the shared bar with the first and second end bars;

wherein the first end bar is positionable substantially circumferentially adjacent to the second end bar when the stent is in the unexpanded state, the first end bar being separable from the second end bar upon translation of at least one of the first and second male members through the respective ones of the slots of the first and second end bars to rotate and translate the shared bar with respect to the first and second end bars thereby expanding the stent to the expanded state.

45. The stent of claim 44 wherein the slots of the first and second end bars each include a plurality of teeth along at least one side thereof, the teeth being sized and configured to provide one-way translation of the respective ones of the first and second male members within the slots such that the stent is not collapsible to the collapsed state upon being expanded to the expanded state.

46. The stent of claim 44 wherein the end bars are oriented substantially parallel with respect to the longitudinal axis.

47. The stent of claim 44 wherein the tubular member comprises a plurality of linkage sections.

48. The stent of claim 47 further comprising at least one flexible section interposed between consecutive linkage sections, the flexible section having first and second ends, the first end thereof being connectable to at least a portion of a first consecutive linkage section and the second end thereof being connectable to at least a portion of a second consecutive linkage section with the flexible section being interposed therebetween.

49. The stent of claim 47 wherein the first end of the flexible section is connectable to the first end bar of the first consecutive linkage section and the second end is connectable to the first end bar of the second consecutive linkage section.

50. A circumferentially nested rotary-slide four-bar linkage stent being expandable from a collapsed state to an expanded state, the stent comprising a tubular member having longitudinal and circumferential axes, the tubular member comprising:

at least one linkage section being disposed along the circumferential axis, the linkage section comprising at least one four-bar structural element, the four-bar structural element comprising;

first and second end bars each having first and second ends, the end bars being disposed along the circumferential axis of the tubular member, the end bars each including a slot being axially disposed along the end bar and extending intermediate the first and second ends thereof; and

third and fourth shared bars each having first and second ends, the shared bars each having first and second male members disposed at the respective ones of the first and second ends thereof, the first and second male members of the third shared bar each being sized and configured to extend into the slots of the respective ones of the first and second end bars to thereby interconnect the third shared bar with the first and second end bars, the first and second male members of the fourth shared bar each being sized and configured to extend into the slots of the respective ones of the second and first end bars to thereby interconnect the fourth shared bar with the first and second end bars;

wherein the first end bar is positionable substantially circumferentially adjacent to the second end bar when the stent is in the unexpanded state, the first end bar being separable from the second end bar upon translation of at least one of the first and second male members of the third shared bar and at least one of the first and second male members of the fourth shared bar through the respective slots of the first and second end bars to rotate and translate the third and fourth shared bars with respect to the first and second end bars thereby expanding the stent to the expanded state.

51. The stent of claim 50 wherein the slots of the first and second end bars each include a plurality of teeth along at least one side thereof, the teeth being sized and configured to provide one-way translation of the respective ones of the first and second male members within the slots such that the stent is not collapsible to the collapsed state upon being expanded to the expanded state.

52. The stent of claim 50 wherein the end bars are oriented substantially parallel with respect to the longitudinal axis.

53. The stent of claim 50 wherein the tubular member comprises a plurality of linkage sections.

54. A circumferentially nested scissor stent being expandable from a collapsed state to an expanded state, the stent comprising a tubular member having longitudinal and circumferential axes, the tubular member comprising:

at least one linkage section being disposed along the circumferential axis, the linkage section comprising at least one structural element, the structural element comprising;

first and second bars each having first and second ends, the bars being disposed along the circumferential axis of the tubular member, the bars being rotatably connected at the first ends thereof to form a coupling, the first bar having an aperture disposed through a portion of the first end thereof; and

an articulating member having first and second ends, the first end of the articulating member being connected to the first end of the second bar adjacent the coupling with the articulating member extending upwardly from therefrom into the aperture of the first bar, the articulating member having a plurality of teeth disposed therealong, the teeth being sized and configured to engage the aperture for providing one-way translational withdrawal of the articulating member from the aperture upon angular separation of the first bar from the second bar;

wherein the first bar is positionable substantially circumferentially adjacent to the second bar when the stent is in the unexpanded state, the first bar being separable from the second bar upon angular rotation of the first bar with respect to the second bar at the coupling thereby expanding the stent to the expanded state, the one-way translational withdrawal of the articulating member from the aperture maintaining angular displacement between the first and second bars at the coupling in order to prevent collapse of the stent to the collapsed state upon being expanded to the expanded state.

55. The stent of claim 54 wherein the linkage section includes a plurality of structural elements being rotatably connected to form a plurality of couplings, wherein each structural element includes an articulating member corresponding to each coupling.