Function-enhanced thrombolytic AV fistula and method

• US 20030028245A1
• Filed: 06/26/2002
• Published: 02/06/2003
• Est. Priority Date: 06/30/2000
• Status: Active Grant

• Current Assignee: LeMaitre Vascular, Incorporated
• Original Assignee: Vascular Architects Incorporated
• Inventors: Barclay, Bruce J., Fogarty, Thomas J.
• Granted Patent: US 6,974,473 B2
• Time in Patent Office: Days
• US Class Current: 623/1.22
• CPC Class Codes: A61F 2/88 the wire-like elements formed as helical or spiral coils forming a net-like or mesh-like structure A61F2/90
• CPC Class Codes: A61F 2210/0076 multilayered, e.g. laminated structures
• CPC Class Codes: A61F 2250/0067 Means for introducing or releasing pharmaceutical products into the body
• CPC Class Codes: A61L 2300/416 Anti-neoplastic or anti-proliferative or anti-restenosis or anti-angiogenic agents, e.g. paclitaxel, sirolimus
• CPC Class Codes: A61L 2300/42 Anti-thrombotic agents, anticoagulants, anti-platelet agents
• CPC Class Codes: A61L 2300/604 Biodegradation
• CPC Class Codes: A61L 2300/622 Microcapsules
• CPC Class Codes: A61L 31/022 Metals or alloys
• CPC Class Codes: A61L 31/048 obtained by reactions only involving carbon-to-carbon unsaturated bonds A61L31/041 takes precedence
• CPC Class Codes: A61L 31/16 Biologically active materials, e.g. therapeutic substances A61L31/047 takes precedence
• CPC Class Codes: C08L 27/18 Homopolymers or copolymers or tetrafluoroethene

Abstract

A coiled stent graft (10), including a thrombolytic agent, is positionable within an AV fistula (4) and optionally into one or both of the artery (9) and the vein (6) to help reduce or eliminate blockages within the blood vessel at the junction (8) between the AV fistula and the blood vessel.

Claims

1. A method for enhancing the function of an AV fistula comprising:

selecting an endoluminal prosthesis comprising a coiled body and a graft material at least partly covering the coiled body to create a coiled stent graft with generally helically-extending turns, said turns having an average width;

said selecting step comprising choosing an endoluminal prosthesis carrying a thrombolytic agent; and

placing the stent graft within an AV fistula and optionally within at least one blood vessel to which the AV fistula is connected, said thrombolytic agent helping to reduce any thrombosis associated with the stent graft.

2. The method according to claim 1 wherein the choosing step is carried out with the chosen endoluminal prosthesis also carrying a non-thrombolytic biologically active agent.

3. The method according to claim 1 wherein the choosing step is carried out with the chosen endoluminal prosthesis also carrying an anti-restenotic agent.

4. The method according to claim 3 wherein the choosing step is carried out with the anti-restenotic agent:

on the surface of the graft material, on the surface of the coiled body, incorporated into the graft material to create an anti-restenotic agent/graft material matrix, or an appropriate combination thereof.

5. The method according to claim 3 wherein the choosing step is carried out with the anti-restenotic agent comprising at least one of rapamycin, taxol, and SNP (sodium nitroprusside).

6. The method according to claim 1 wherein the placing step is carried out with the stent graft placed within the AV fistula and at least one blood vessel so the stent graft extends across the junction between the AV fistula and the at least one blood vessel.

7. The method according to claim 6 wherein the selecting and placing steps are carried out so that the turns of the stent graft at the junction are spaced-apart from one another so as to not block fluid flow through the blood vessel.

8. The method according to claim 6 wherein the selecting and placing steps are carried out so that the turns of the stent graft at the junction are next to one another so to effectively block fluid flow along the blood vessel on one side of the junction.

9. The method according to claim 1 wherein the placing step is carried out with the stent graft placed within the AV fistula and a vein.

10. The method according to claim 1 wherein the choosing step is carried out with the thrombolytic agent on the surface of the graft material.

11. The method according to claim 1 wherein the choosing step is carried out with the thrombolytic agent on the surface of the coiled body.

12. The method according to claim 1 wherein the choosing step is carried out with the thrombolytic agent incorporated into the graft material to create a thrombolytic agent/graft material matrix.

13. The method according to claim 1 wherein the choosing step is carried out with the thrombolytic agent:

on the surface of the graft material, on the surface of the coiled body, incorporated into the graft material to create a thrombolytic agent/graft material matrix, or an appropriate combination thereof.

14. The method according to claim 1 wherein the choosing step is carried out with the thrombolytic agent comprising at least one of tPA, Reteplase and Urokinase.

15. The method according to claim 1 wherein the choosing step is carried out with a delay-release material associated with the thrombolytic agent to delay the release of the thrombolytic agent.

16. The method according to claim 15 wherein the choosing step is carried out with the delay-release material comprising a biodegradable, delay-release layer.

17. The method according to claim 1 wherein the choosing step is carried out with the thrombolytic agent microencapsulated using a biodegradable encapsulation material so as to delay migration of said thrombolytic agent from said prosthesis.

18. A method for enhancing the function of an AV fistula comprising:

selecting an endoluminal prosthesis comprising a coiled body, a graft material at least partly covering the coiled body and a thrombolytic agent carried by at least one of the coiled body and the graft material, so to create a coiled stent graft with generally helically-extending turns;

placing the stent graft within an AV fistula and an associated vein so the stent graft extends across the junction between the AV fistula and the vein, said thrombolytic agent helping to reduce any thrombosis associated with the stent graft;

the selecting and placing steps being carried out so that the turns of the stent graft at the junction are separated by a gap so to not block fluid flow along the vein.

19. A thrombolytic AV fistula assembly comprising:

an artificial AV fistula comprising a tubular body having a venous end and an arterial end;

a coiled stent graft comprising a coiled body, a graft material at least partially covering the coiled body, and a thrombolytic agent carried by at least one of the coiled body and the graft material;

the coiled stent graft having generally helically-extending turns, said turns having edges; and

the stent graft housable at least partially within the AV fistula at at least one of venous and arterial ends, said thrombolytic agent helping to reduce any thrombosis associated with the stent graft.

20. The assembly according to claim 19 wherein said edges of adjacent turns are adjacent to one another.

21. The assembly according to claim 19 wherein at least some of the turns are spaced-apart by gaps so that said spaced-apart turns do not overlap one another.

22. The assembly according to claim 21 wherein the gaps are generally equal in length.

23. The assembly according to claim 21 wherein the lengths of the gaps vary by more than 100%.

24. The assembly according to claim 19 wherein the coiled body comprises a framework of lateral rails and connectors.

25. The assembly according to claim 19 wherein the graft material is synthetic graft material.

26. The assembly according to claim 25 wherein the synthetic graft material is expanded PTFE.

27. The assembly according to claim 19 wherein the thrombolytic agent is on the surface of the graft material.

28. The assembly according to claim 19 wherein the thrombolytic agent is on the surface of the coiled body.

29. The assembly according to claim 19 wherein the thrombolytic agent is incorporated into the graft material to create a thrombolytic agent/graft material matrix.

30. The assembly according to claim 19 wherein the thrombolytic agent is:

on the surface of the graft material, on the surface of the coiled body, incorporated into the graft material to create a thrombolytic agent/graft material matrix, or an appropriate combination thereof.

31. The assembly according to claim 19 wherein the thrombolytic agent comprises at least one of tPA, Reteplase and Urokinase.

32. The assembly according to claim 19 further comprising a delay-release material associated with the thrombolytic agent to delay the release of the thrombolytic agent.

33. The assembly according to claim 32 wherein the delay-release material comprises a biodegradable, delay-release layer.

34. The assembly according to claim 19 wherein the thrombolytic agent is microencapsulated using a biodegradable encapsulation material so as to delay migration of said thrombolytic agent from said prosthesis.

35. A thrombolytic AV fistula assembly comprising:

an artificial AV fistula comprising a tubular body having a venous end and an arterial end;

a coiled stent graft comprising a coiled body, a graft material at least partially covering the coiled body, and a thrombolytic agent carried by at least one of the coiled body and the graft material, the turns of the coiled stent graft being generally helically-extending and spaced-apart by gaps;

the lengths of the gaps varying by more than 100%; and

the stent graft housable partially within the AV fistula and extending past at least one of the venous and arterial ends, said thrombolytic agent helping to reduce any thrombosis associated with the stent graft.