METHODS AND APPARATUS FOR LUMINAL STENTING

• US 20090287288A1
• Filed: 04/17/2009
• Published: 11/19/2009
• Est. Priority Date: 05/25/2004
• Status: Active Grant

• Current Assignee: Covidien LP (Medtronic Plc)
• Original Assignee: Chestnut Medical Technologies, Inc. (Medtronic Plc)
• Inventors: Tran, Quang Quoc, Berez, Aaron Lee
• Granted Patent: US 8,628,564 B2
• Time in Patent Office: Days
• US Class Current: 623/1.200
• CPC Class Codes: A61B 17/12 for ligaturing or otherwise compressing tubular parts of the body, e.g. blood vessels, umbilical cord specially adapted for vas deferens or fallopian tubes A61F6/20; materials for ligaturing blood vessels A61L17/00
• CPC Class Codes: A61B 17/12022 Occluding by internal devices, e.g. balloons or releasable wires plugging an opening in the wall of an organ A61B17/0057; occluders for the cervical canal A61F6/146; vas deferens occluders A61F6/20
• CPC Class Codes: A61B 17/12109 in a blood vessel
• CPC Class Codes: A61B 17/12118 for positioning in conjunction with a stent
• CPC Class Codes: A61B 17/12168 having a mesh structure A61B17/1214 takes precedence
• CPC Class Codes: A61B 2017/00867 shape memory effect for prostheses A61F2210/0014
• CPC Class Codes: A61B 2017/1205 Introduction devices
• CPC Class Codes: A61B 2017/12054 Details concerning the detachment of the occluding device from the introduction device
• CPC Class Codes: A61B 2017/22001 Angioplasty, e.g. PCTA
• CPC Class Codes: A61F 2/01 Filters implantable into blood vessels
• CPC Class Codes: A61F 2/013 Distal protection devices, i.e. devices placed distally in combination with another endovascular procedure, e.g. angioplasty or stenting
• CPC Class Codes: A61F 2/06 Blood vessels
• CPC Class Codes: A61F 2/07 Stent-grafts
• CPC Class Codes: A61F 2/82 Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents stent-grafts for tubular structures of the body other than blood vessels A61F2/04; stent-grafts for blood vessels A61F2/07; instruments specially adapted for placement or removal of stents or stent-grafts A61F2/95; for closing wounds, or holding wounds closed A61B17/04 - A61B17/115; dilators A61M29/00
• CPC Class Codes: A61F 2/844 folded prior to deployment
• CPC Class Codes: A61F 2/852 Two or more distinct overlapping stents
• CPC Class Codes: A61F 2/86 Stents in a form characterised by the wire-like elements; Stents in the form characterised by a net-like or mesh-like structure
• CPC Class Codes: A61F 2/90 characterised by a net-like or mesh-like structure
• CPC Class Codes: A61F 2/915 with bands having a meander structure, adjacent bands being connected to each other
• CPC Class Codes: A61F 2/95 Instruments specially adapted for placement or removal of stents or stent-grafts
• CPC Class Codes: A61F 2/9522 : Means for mounting a stent or stent-graft onto or into a placement instrument
• CPC Class Codes: A61F 2/958 : Inflatable balloons for placing stents or stent-grafts
• CPC Class Codes: A61F 2/966 : with relative longitudinal movement between outer sleeve and prosthesis, e.g. using a push rod
• CPC Class Codes: A61F 2002/016 : made from wire-like elements
• CPC Class Codes: A61F 2002/018 : made from tubes or sheets of material, e.g. by etching or laser-cutting
• CPC Class Codes: A61F 2002/823 : Stents, different from stent-grafts, adapted to cover an aneurysm
• CPC Class Codes: A61F 2002/826 : more than one stent being applied sequentially
• CPC Class Codes: A61F 2002/91558 : connected peak to peak
• CPC Class Codes: A61F 2002/9505 : having retaining means other than an outer sleeve, e.g. male-female connector between stent and instrument
• CPC Class Codes: A61F 2002/9528 : for retrieval of stents
• CPC Class Codes: A61F 2002/9534 : for repositioning of stents
• CPC Class Codes: A61F 2002/9665 : with additional retaining means
• CPC Class Codes: A61F 2230/001 : Figure-8-shaped, e.g. hourglass-shaped
• CPC Class Codes: A61F 2230/0069 : cylindrical
• CPC Class Codes: A61F 2230/0078 : hyperboloidal
• CPC Class Codes: A61F 2230/008 : paraboloidal
• CPC Class Codes: A61F 2230/0091 : helically-coiled or spirally-coiled, i.e. having a 2-D spiral cross-section
• CPC Class Codes: A61F 2230/0095 : Saddle-shaped
• CPC Class Codes: A61F 2250/0015 : differing in density or specific weight
• CPC Class Codes: A61F 2250/0063 : Nested prosthetic parts

Abstract

Described herein are flexible implantable occluding devices that can, for example, navigate the tortuous vessels of the neurovasculature. The occluding devices can also conform to the shape of the tortuous vessels of the vasculature. In some embodiments, the occluding devices can direct blood flow within a vessel away from an aneurysm or limit blood flow to the aneurysm. Some embodiments describe methods and apparatus for adjusting, along a length of the device, the porosity of the occluding device. In some embodiments, the occluding devices allows adequate blood flow to be provided to adjacent structures such that those structures, whether they are branch vessels or oxygen-demanding tissues, are not deprived of the necessary blood flow.

Claims

1. A stent, for implanting in a patient'"'"'s vessel, comprising:

a proximal portion having a proximal end;

a distal portion having a distal end;

a stent length extending from the proximal end to the distal end;

a stent wall that defines a lumen extending between the proximal end and the distal end, the stent wall having a delivery configuration and an expanded configuration;

wherein, when in the expanded configuration, the stent wall has a porosity that is changeable in a discrete location proximal to the distal portion by changing the stent length.

2. The stent of claim 1, wherein the porosity of the stent wall is decreased as the stent length is decreased.

3. The stent of claim 1, wherein, as the stent length is changed, the stent wall porosity changes in the discrete location relative to the stent wall porosity in at least one of the proximal portion and the distal portion.

4. The stent of claim 3, wherein, when the stent length is decreased, the porosity of the stent wall in the discrete location is reduced relative to the porosity of the stent wall in the proximal portion and the distal portion.

5. The stent of claim 1, wherein axially compressing the stent decreases the porosity of the stent.

6. The stent of claim 1, wherein the stent automatically changes from the delivery configuration to the expanded configuration when unrestrained.

7. The stent of claim 1, wherein the stent is radially collapsible, after changing from the delivery configuration to the expanded configuration, by increasing the stent length.

8. The stent of claim 1, wherein the stent is radially collapsible, after changing from the delivery configuration to the expanded configuration, by advancement of a catheter over the expanded stent.

9. The stent of claim 1, wherein the stent comprises a first stent length when the stent is in the delivery configuration, and a second stent length, shorter than the first stent length, when the stent is in the expanded configuration.

10. The stent of claim 9, wherein the porosity of the stent can be reduced in the discrete location by decreasing the stent length beyond the second stent length.

11. The stent of claim 1, wherein, when in the expanded configuration, the porosity is changeable in the discrete location by changing the stent length without substantially changing a cross-sectional dimension of the stent, the cross-sectional dimension spanning the lumen.

12. The stent of claim 1, wherein, when in the expanded configuration, the stent length is reducible without substantially changing a radial cross-sectional dimension of the stent lumen.

13. A system, for implanting a stent in a patient'"'"'s vessel, comprising:

an elongate body, having a proximal portion, a distal portion, and a body lumen extending from the proximal portion to the distal portion, the distal portion being configured to extend within a blood vessel of a patient; and

a stent expandable from a compressed configuration to an expanded configuration, the stent having a proximal end, a distal end, a stent lumen extending from the proximal end to the distal end, and a stent wall that has, in the expanded configuration, an adjustable porosity;

wherein the stent in the compressed configuration is configured to be slideably positioned within the body lumen and to change to an expanded configuration as the stent is advanced out of the body lumen; and

wherein, when the distal end of the stent is in the expanded configuration, the adjustable porosity is adjustable by advancing or withdrawing the proximal end of the stent relative to the distal end of the stent.

14. The system of claim 13, wherein the adjustable porosity is adjustable in multiple discrete locations along a length of the stent wall.

15. The system of claim 13, wherein, when stent is in the expanded configuration, the adjustable porosity is decreasable in discrete, spatially separate sections of the stent wall as the proximal end of the stent is advanced toward the distal end of the stent.

16. The system of claim 13, wherein, when stent is in the expanded configuration, the adjustable porosity is increasable in the discrete, spatially separate sections of the stent wall as the proximal end is withdrawn from the distal end of the stent.

17. The system of claim 13, wherein axially compressing the stent, when the stent is in the expanded configuration, decreases the porosity of at least a portion of the stent.

18. The system of claim 13, wherein the stent automatically changes from the delivery configuration to the expanded configuration when unrestrained.

19. The system of claim 13, wherein the stent is collapsible, after changing from the delivery configuration to the expanded configuration, by increasing a length of the stent.

20. The stent of claim 13, wherein:

the stent has a length extending from the proximal end to the distal end; and

when in the expanded configuration, the stent length is reducible without substantially changing a radial cross-sectional dimension of the stent lumen.

21. A stent, for implanting in a body lumen of a patient, comprising:

a proximal portion and a distal portion;

a stent wall that defines a lumen extending from the proximal portion to the distal portion, the stent wall having a compressed configuration and an expanded configuration;

wherein, when in the expanded configuration, the stent wall has a variable porosity that is adjustable by relative movement of the proximal portion with respect to the distal portion.

22. The stent of claim 21, wherein the porosity of the stent wall is adjustable in a plurality of spatially separated locations between the proximal and distal portions.

23. The stent of claim 21, wherein the porosity of the stent wall is decreased when a length of the stent, extending from the proximal portion to the distal portion, is decreased.

24. The stent of claim 21, wherein, when a length of the stent, extending from the proximal portion to the distal portion, is changed, a porosity of the stent wall in a first region, located between the proximal portion and the distal portion, changes relative to a porosity of the stent wall in a second region, located in at least one of the proximal portion and the distal portion.

25. The stent of claim 24, wherein, when the length of the stent is decreased, the porosity in the first region is reduced relative to the porosity in the second region.

26. The stent of claim 21, wherein, when the stent is in the expanded configuration, axially compressing the stent decreases the porosity of the stent.

27. The stent of claim 21, wherein:

the stent has a length extending from the proximal portion to the distal portion; and

when in the expanded configuration, the stent length is substantially reducible without substantially changing a radial cross-sectional dimension of the stent lumen.

28. A stent, for implanting in a patient, comprising a stent wall that has an adjustable porosity, such that a porosity of at least a portion of the stent wall can be adjusted while the stent is positioned in the patient.

29. A stent, for implanting in a patient'"'"'s vessel, comprising:

a stent wall configured to change between a compressed configuration and an expanded configuration, the stent wall having a proximal portion, a distal portion, and a middle portion extending between the proximal portion and the distal portion;

wherein the middle portion of the stent has a variable porosity that is adjustable when the distal portion is in the expanded configuration.

30. The stent of claim 29, wherein the porosity of the middle portion decreases when a length of the stent extending from the proximal portion to the distal portion decreases.

31. The stent of claim 29, wherein the porosity of the middle portion changes by changing a length of the middle portion.

32. The stent of claim 31, wherein, when a length of the middle portion is decreased, the porosity of the middle portion is reduced relative to a porosity in at least one of the proximal portion and the distal portion.

33. The stent of claim 29, wherein, when the stent is in the expanded configuration, axially compressing the stent decreases the porosity of the middle portion.

34. The stent of claim 29, wherein:

the stent has a length extending from the proximal portion to the distal portion; and

when in the expanded configuration, the stent length is substantially reducible without substantially changing a radial cross-sectional dimension of the stent.