Stent-graft-membrane and method of making the same

• US 20040167606A1
• Filed: 12/24/2003
• Published: 08/26/2004
• Est. Priority Date: 08/14/1998
• Status: Abandoned Application

• Current Assignee: Lifeport Sciences LLC (Acacia Research Corporation)
• Original Assignee: Lifeport Sciences LLC (Acacia Research Corporation)
• Inventors: Chouinard, Paul F.
• Application Number:
  US10/746,416
• Publication Number:
  US 20040167606A1
• Time in Patent Office: Days
• US Class Current: 623/1.13
• CPC Class Codes: A61F 2/07 Stent-grafts
• CPC Class Codes: A61F 2/885 comprising a coil including a plurality of spiral or helical sections with alternate directions around a central axis
• CPC Class Codes: A61F 2/90 characterised by a net-like or mesh-like structure
• CPC Class Codes: A61F 2002/041 Bile ducts
• CPC Class Codes: A61F 2002/072 Encapsulated stents, e.g. wire or whole stent embedded in lining
• CPC Class Codes: A61F 2002/075 the stent being loosely attached to the graft material, e.g. by stitching
• CPC Class Codes: A61F 2210/0004 bioabsorbable
• CPC Class Codes: A61F 2210/0076 multilayered, e.g. laminated structures
• CPC Class Codes: A61F 2250/0024 made from both porous and non-porous parts, e.g. adjacent parts
• CPC Class Codes: A61F 2250/0028 differing in fibre orientations
• CPC Class Codes: A61F 2250/0098 radio-opaque, e.g. radio-opaque markers

Abstract

A braided self-expandable stent-graft-membrane made of elongated members forming a generally tubular body. A membrane layer and graft layer are disposed on a endoprosthesis such as a stent. The membrane layer is substantially impermeable to fluids. The outermost layer is biocompatible with the body tissue. The innermost layer is biocompatible with the fluid in the passage. An embodiment includes a graft layer disposed on the inside of a stent and a membrane layer disposed on the outside of the stent. The innermost layer is biocompatible with the fluid in the passage. The stent-graft-membrane is used at a treatment site in a body vessel or organ where it is desirous to exclude a first fluid located outside the endoprosthesis from reaching a second fluid located in the lumen. The membrane may be made of silicone or polycarbonate urethane. The graft may be braided, woven, spun or spray-cast PET, PCU, or PU fibers. The layers may include ePTFE or PTFE.

Claims

1. An implantable endoprosthesis comprising:

a first number of elongated members wound helically in a first common direction and crossing a second number of elongated members wound helically in a second common direction, the crossing of the first and second elongated members defining an angle therebetween and forming a generally tubular body having an inside surface, outside surface, ends and a middle portion therebetween, the first and second elongated members braided in a braid pattern and configured to be constrainable to a reduced diameter and self-expandable to an increased diameter, the generally tubular body adapted to be disposed at a treatment site in at least one of a body vessel or organ having body tissue;

a passage extending in a longitudinal direction at least partially through the generally tubular body, the passage adapted to at least partially contain a fluid;

one or more outside layers disposed on at least a portion of the outside of the tubular body, an outermost layer of the one or more outside layers being biocompatible with the body tissue;

one or more inside layers disposed on at least a portion of the inside of the tubular body, an innermost layer of the one or more inside layers being biocompatible with the fluid in the passage;

wherein at least one of the one or more outside layers or the one or more inside layers are substantially impermeable to fluids.

2. The implantable endoprosthesis of claim 1 wherein the one or more layers comprise one or more membrane layers having an average permeability ranging from about 0 cc/cm²/min. to about 100 cc/cm²/min. at 120 mmHg and one or more graft layers having an average permeability ranging from about 50 cc/cm²/min. to about 5000 cc/cm²/min. at 120 mmHg.

3. The implantable endoprosthesis of claim 1 wherein the one or more outside layers is a membrane made of silicone or polycarbonate urethane and the one or more inside layers is a graft made of PET.

4. The implantable endoprosthesis of claim 1 wherein the one or more inside layers is made of ePTFE or PTFE.

5. The implantable endoprosthesis of claim 1 wherein the implantable endoprosthesis is configured to substantially separate a first fluid located outside the endoprosthesis from a second fluid located in the passage.

6. The implantable endoprosthesis of claim 5 wherein the first fluid includes bile and the second fluid includes blood.

7. The implantable endoprosthesis of claim 1 wherein the implantable endoprosthesis is configured to be disposed at a transjugular intrahepatic portosystemic shunt (TIPS) treatment site.

8. The implantable endoprosthesis of claim 1 wherein the generally tubular body is made of at least one of a metal, plastic, bioabsorbable or other synthetic or natural materials.

9. An implantable endoprosthesis comprising:

a first set of filaments each of which extends in a configuration along a center line and having a first common direction of winding;

a second set of filaments each of which extends in a configuration along a center line and having a second common direction of winding, the first and second filaments forming a stent layer, one or more membrane layers having a first average permeability ranging from about 0 cc/cm²/min. to about 100 cc/cm²/min. at 120 mmHg disposed over or on at least one of an inside, interstices, or outside of the stent or a graft; and

one or more graft layers having a second average permeability ranging from about 50 cc/cm²/min. to about 5000 cc/cm²/min. at 120 mmHg disposed over or on at least one of an inside, interstices, or outside of the stent;

wherein the first and second set of filaments, one or more membrane layers and one or more graft layers form a self expanding structure having one or more layers, inside surface, outside surface, proximal end, distal end, and a lumen, the inside surface being substantially biocompatible with a fluid flow through the body lumen and the outside surface being substantially biocompatible with a body tissue.

10. The implantable endoprosthesis of claim 9 wherein the first average permeability is less than the second average permeability.

11. The implantable endoprosthesis of claim 9 wherein the one or more graft layers include polyethylene terephthalate (PET), expanded. polytetrafluoroethylene (ePTFE), polycarbonate urethane (PCU), polyurethane (PU), or combinations thereof.

12. The implantable endoprosthesis of claim 9 wherein the one or more membrane layers include at least one of siloxane polymers, polyurethane polymers, polycarbonate urethanes, PTFE, ePTFE, or combinations thereof.

13. The implantable endoprosthesis of claim 9 wherein the one or more membrane layers are disposed between the graft layer and the stent layer.

14. The implantable endoprosthesis of claim 9 wherein the one or more graft layers are disposed between the membrane layer and the stent layer.

15. The implantable endoprosthesis of claim 9 wherein the stent layer is disposed between the membrane layer and the graft layer.

16. The implantable endoprosthesis of claim 9 wherein the stent-graft-membrane is configured to substantially exclude a first fluid located outside the implantable endoprosthesis surface from reaching a second fluid located in the lumen.

17. The implantable endoprosthesis of claim 9 wherein an inside layer includes PET.

18. The implantable endoprosthesis of claim 9 wherein an outside layer includes silicone elastomer.

19. The implantable endoprosthesis of claim 18 wherein the silicone elastomer is a coating.

20. The implantable endoprosthesis of claim 9 wherein an outside layer is a polymer resistant to fluid permeability.

21. The implantable endoprosthesis of claim 9 wherein at least one of the stent, graft, or membrane layers is embedded in at least one of the other.

22. A method of making a stent-graft-membrane comprising the steps:

forming a first number of elongated members wound helically in a first common direction and crossing a second number of elongated members wound helically in a second common direction, the crossing of the first and second elongated members defining an angle therebetween and forming a generally tubular body having an inside surface, outside surface, ends and a middle portion therebetween, the first and second elongated members braided in a braid pattern and configured to be constranable to a reduced diameter and self-expandable to an increased diameter, the generally tubular body adapted to be disposed at a treatment site in at least one of a body vessel or organ having body tissue;

forming a passage extending in a longitudinal direction at least partially through the generally tubular body, the passage adapted to at least partially contain a fluid;

forming one or more outside layers on at least a portion of the outside surface of the tubular body, an outermost layer of the one or more outside layers being biocompatible with the body tissue;

forming one or more inside layers on at least a portion of the inside surface of the tubular body, an innermost layer of the one or more inside layers being biocompatible with the fluid in the passage;

wherein at least one of the one or more outside layers or the one or more inside layers are substantially impermeable to a fluid.

23. A method of making a stent-graft-membrane comprising the steps:

braiding bioabsorbable filaments to form a tubular braid, the braid having a braid angle;

disposing the braid on a mandrel;

annealing the braid for a predetermined time to form an annealed stent;

removing the stent from the mandrel, the stent having a filament crossing angle;

forming a graft having a first permeability ranging from about 50 cc/cm²/min. to about 5000 cc/cm²/min. 120 mmHg on at least one of an inside or an outside surface of the stent;

adhering at least a portion of the graft to the annealed stent; and

forming a membrane having a second average permeability ranging from about 0 cc/cm²/min to about 100 cc/cm²/min. at 120 mmHg on at least a portion of the stenL.

24. A braided implantable endoprosthesis comprising:

a first number of elongated members wound helically in a first common direction and crossing a second number of elongated members wound helically in a second common direction, the crossing of the first and second elongated members defining an angle therebetween and forming a generally tubular body having an inside surface, outside surface, ends and a middle portion therebetween, the first and second elongated members braided in a braid pattern and configured to be constrainable to a reduced diameter and self-expandable to an increased diameter, the generally tubular body adapted to be disposed at a treatment site in at least one of a body vessel or organ having body tissue;

a passage extending in a longitudinal direction at least partially through the generally tubular body, the passage adapted to at least partially contain a fluid;

one or more outside layers disposed on at least a portion of the outside of the tubular body, at least one of the one or more outside layers being a membrane made of a silicone or a polycarbonate urethane material biocompatible with the body tissue;

one or more inside layers disposed on at least a portion of the inside of the tubular body, at least one of the one or more inside layers being a graft made of braided PET material biocompatible with the fluid in the passage;

wherein the braided implantable endoprosthesis is configured such that at least one of the one or more layers are substantially impermeable to a fluid and substantially separate a first body fluid located outside the implantable endoprosthesis from a second body fluid located in the passage.

25. The braided implantable endoprosthesis of claim 24 wherein a first end portion of the braided implantable endoprosthesis is configured to be disposed in a portal vein and the other end portion of the braided implantable endoprosthesis is configured to be disposed in a hepatic vein.

26. The braided implantable endoprosthesis of claim 24 wherein a middle portion of the braided implantable endoprosthesis is configured to be disposed in a liver.

27. The braided implantable endoprosthesis of claim 24 wherein at least one portion of the braided implantable endoprosthesis has exposed elongated members.

28. A method of using a stent-graft-membrane comprising the steps:

identifying a treatment site;

determining the tissue, organ or fluid at the treatment site that the inside surface and the outside surface of the stent-graft-membrane are to be associated with;

determining one or more materials for the inside and outside surfaces of the stent-graft-membrane that are substantially biocompatible with the tissue, organ or fluid at the treatment site;

providing a stent-graft-membrane, the stent-graft-membrane having a first number of elongated members wound helically in a first common direction and crossing a second number of elongated members wound helically in a second common direction, the crossing of the first and second elongated members defining an angle therebetween and forming a generally tubular body having an inside surface, outside surface, ends and a middle portion therebetween, the first and second elongated members braided in a braid pattern and configured to be constrainable to a reduced diameter and selfexpandable to an increased diameter, the generally tubular body adapted to be disposed at a treatment site in at least one of a body vessel or organ having body tissue;

a passage extending in a longitudinal direction at least partially through the generally tubular body, the passage adapted to at least partially contain a fluid;

one or more outside layers disposed over or on at least a portion of the outside of the tubular body, an outermost layer of the one or more outside layers being biocompatible with the body tissue;

one or more inside layers disposed over or on at least a portion of the inside of the tubular body, an innermost layer of the one or more inside layers being biocompatible with the fluid in the passage;

wherein at least one of the one or more outside layers or the one or more inside layers are substantially impermeable to fluids;

inserting the stent-graft-membrane in a delivery device;

inserting the delivery device into a body and delivering the stent-graft-membrane to the treatment site; and

deploying the stent-graft-membrane into a position at the treatment site.