Methods and apparatus for luminal stenting

• US 8,628,564 B2
• Filed: 04/17/2009
• Issued: 01/14/2014
• Est. Priority Date: 05/25/2004
• Status: Active Grant

• Current Assignee: Covidien LP (Medtronic Plc)
• Original Assignee: Covidien LP (Medtronic Plc)
• Inventors: Berez, Aaron L., Tran, Quang Q.
• Primary Examiner(s): MCEVOY, THOMAS M
• Application Number:
  US12/425,604
• Publication Number:
  US 20090287288A1
• Time in Patent Office: 1,733 Days
• Field of Search: 623/1.11, 623/1.12, 623/1.15, 623/1.17, 623/1.4, 623/1.5, 623/1.51, 623/1.53
• US Class Current: 623/1.15
• 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 system, for treatment of an aneurysm, comprising:

a guidewire for guiding the system to an aneurysm;

a stent, for implanting in a patient'"'"'s vessel, comprising;

a plurality of braided strands;

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, the stent wall being self-expandable to the expanded configuration, such that the stent wall engages an inner surface of the vessel with an outer surface of the stent wall being apposed to the vessel surface, the stent wall having a self-expanded porosity while in the expanded configuration;

wherein, when in the expanded configuration and while the stent wall remains engaged with the vessel surface, the stent wall has a porosity that is changeable in a discrete location proximal to the distal portion by changing the stent length by a user input, such that the discrete location transitions from the self-expanded porosity to an adjusted porosity, while the distal portion maintains the self-expanded porosity; and

a stent adjuster configured to engage an inner surface of the stent while at least a portion of the stent adjuster is within the stent and change the stent from the expanded configuration to the adjusted configuration based on the input comprising movement, by a user, of the stent adjuster while engaged with the inner surface of the stent;

wherein the plurality of braided strands comprises a first plurality of strands of a first metallic material and a second plurality of strands, of a second metallic material, different from the first material, wherein each of the first plurality of strands has a first width and each of the second plurality of strands has a second width, different than the first width;

wherein the first material comprises platinum.

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

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

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

7. The system 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 system 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 system 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 system 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 system 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 system 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. The system of claim 1, wherein the second material comprises at least one of nitinol and stainless steel.

14. The system of claim 1, wherein the second material consists essentially of a cobalt nickel alloy and the first material consists essentially of a platinum tungsten alloy.

15. The system of claim 1, wherein the plurality of braided strands comprises 48 strands.

16. The system of claim 1, wherein the stent has a stent diameter of between about 2.75 mm and about 4.25 mm.

17. The system of claim 1, wherein the stent adjuster comprises an elongate member.

18. The system of claim 1, wherein the stent adjuster comprises a lattice density adjusting implement.

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

a guidewire for guiding the system in a patient'"'"'s vessel;

a stent adjuster and a stent, the stent comprising;

a plurality of braided strands;

a proximal portion having a proximal end;

a distal portion having a distal end;

a medial portion between the proximal portion and the distal portion;

the stent having a delivery configuration, a self-expanded configuration, and an adjusted configuration;

wherein the stent is self-expandable from the delivery configuration to the expanded configuration, such that an outer surface of the stent engages an inner surface of the vessel;

wherein the plurality of braided strands comprises a first plurality of strands of a first metallic material and a second plurality of strands, of a second metallic material, different from the first material, wherein each of the first plurality of strands has a first width and each of the second plurality of strands has a second width, different than the first width;

wherein the first material comprises platinum;

wherein, when in the expanded configuration and while the stent remains engaged with the vessel surface, the medial portion has a self-expanded porosity that is changeable by changing a stent length of the medial portion by an input, such that the medial portion transitions from the self-expanded porosity to an adjusted porosity; and

wherein, when the distal portion of the stent is in the expanded configuration, the changeable porosity in the medial portion is changeable by advancing or withdrawing the proximal portion of the stent relative to the distal portion of the stent to change the length of the medial portion, while the distal portion maintains the self-expanded porosity;

wherein the stent adjuster is configured to be positioned in the vessel, engage an inner surface of the stent, and change the medial portion of the stent from the self-expanded porosity to the adjusted porosity, while at least a portion of the stent adjuster is within the stent, based on the input comprising movement, by a user, of the stent adjuster while engaged with the inner surface of the stent.

20. The system of claim 19, wherein the changeable porosity is changeable in multiple discrete locations along a length of the stent wall.

21. The system of claim 19, wherein, when stent is in the expanded configuration, the changeable 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.

22. The system of claim 19, wherein, when stent is in the expanded configuration, the changeable porosity is increasable in discrete, spatially separate sections of the stent wall as the proximal end is withdrawn from the distal end of the stent.

23. The system of claim 19, wherein axially compressing the stent, when the stent is in the expanded configuration, decreases the porosity of at least a portion of the stent.

24. The system of claim 19, wherein the stent automatically changes from the delivery configuration to the expanded configuration when unrestrained.

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

26. The stent of claim 19, wherein:

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

27. The system of claim 19, wherein the second material comprises at least one of nitinol and stainless steel.

28. The system of claim 19, wherein the second material consists essentially of a cobalt nickel alloy and the first material consists essentially of a platinum tungsten alloy.

29. The system of claim 19, wherein the plurality of braided strands comprises 48 strands.

30. The system of claim 19, wherein the stent has a stent diameter of between about 2.75 mm and about 4.25 mm.

31. The system of claim 19, wherein the stent adjuster comprises an elongate member.

32. The system of claim 19, wherein the stent adjuster comprises a lattice density adjusting implement.