Endovascular graft and process for bridging a defect in a main vessel near one of more branch vessels

• US 6,395,018 B1
• Filed: 02/09/1998
• Issued: 05/28/2002
• Est. Priority Date: 02/09/1998
• Status: Expired due to Term

• Current Assignee: Envatech, LLC
• Original Assignee: Wilfrido R. Castaneda
• Inventors: Castaneda, Wilfrido R.
• Primary Examiner(s): Milano, Michael J.
• Application Number:
  US09/020,869
• Time in Patent Office: 1,569 Days
• Field of Search: 623/1.11,1.13,1.16,1.19,1.21,1.23,1.34,1.35
• US Class Current: 623/1.13
• CPC Class Codes: A61F 2/07 Stent-grafts
• CPC Class Codes: A61F 2/90 characterised by a net-like or mesh-like structure
• CPC Class Codes: A61F 2002/061 provided with means for allowing access to secondary lumens
• CPC Class Codes: A61F 2002/065 Y-shaped blood vessels
• CPC Class Codes: A61F 2002/075 the stent being loosely attached to the graft material, e.g. by stitching
• CPC Class Codes: A61F 2240/002 Designing or making customized prostheses

Abstract

An endovascular graft for bridging a defect in a main vessel near one or more branch vessels is provided. A graft, consistent with one embodiment of the invention, includes a tubular member which defines one or more apertures and is adapted for expansion against inner wall of a main vessel above one or more branch vessels. Each aperture defined by the tubular member is alignable with at least one of the one or more branch vessels and may have an area which is as large as or larger than the opening of the respective branch vessel(s) when the tubular member is expanded against the inner wall of the main vessel. Embodiments of the invention are particularly suited for bridging abdominal aortic aneurysms having short or no proximal necks, a significant factor limiting the use of conventional grafts for bridging abdominal aortic aneurysms.

Claims

1. A stent-graft for bridging an aneurysm in an aorta, the aneurysm being at least partially disposed between two renal arteries and two iliac arteries, comprising:

a graft material defining two renal apertures each oriented to align with one of the two renal arteries when the stent-graft is in an expanded state; and

a stent system for supporting the graft material in a contracted state wherein each renal aperture is contracted and the expanded state wherein each renal aperture is expanded;

wherein the stent system, when in the expanded state, is adapted to press against a portion of the aortic wall above the first renal artery and against a portion of the aortic wall above the second renal artery;

wherein the graft material defines a mesenteric aperture oriented to align with a superior mesenteric artery when the stent-graft is in an expanded state.

2. The stent-graft of claim 1, wherein the stent system supports the mesenteric aperture and when in the expanded state, is adapted to press against a portion of the aortic wall above the superior mesenteric artery.

3. The stent-graft of claim 2, wherein the graft material defines a celiac aperture oriented to align with a celiac axis artery when the stent-graft is in the expanded state.

4. The stent-graft of claim 3, wherein the stent system supports the celiac aperture and when in the expanded state, is adapted to press against a portion of the inner wall of the aorta above the celiac axis artery.

5. A process of bridging a defect disposed in a main vessel near one or more branch vessels, comprising:

using three dimensional imaging, positioning, within the main vessel, a contracted graft having a sidewall defining one or more apertures;

using three dimensional imaging, aligning the graft within the main vessel such that each aperture aligns with at least a respective one of the branch vessels; and

expanding the graft to an expanded state wherein the one or more apertures are aligned with the one or more branch vessels and the graft presses against a wall of the main vessel.

6. The process of claim 5, wherein aligning the graft includes partially expanding the graft and rotating the graft while partially expanded about its longitudinal axis to align the one or more apertures in the sidewall of the graft with the one or more branch vessels.

7. The process of claim 5, wherein the main vessel is an aorta and the defect is an aneurysm.

8. A process of bridging a defect disposed in a main vessel near one or more branch vessels, comprising:

inserting, within the main vessel, a graft in a contracted state, the graft defining one or more apertures;

aligning the graft within the main vessel such that each aperture aligns with at least a respective one of the branch vessels; and

expanding the graft to an expanded state wherein the one or more apertures are aligned with the one or more branch vessels and the graft presses against a wall of the main vessel;

wherein aligning the graft includes partially expanding the graft and aligning the graft while partially expanded;

wherein partially expanding the graft includes maintaining the graft in at least a partial martensite phase while forcibly expanding the graft.

9. The process of claim 8, wherein aligning includes using three-dimensional imaging.

10. The process of claim 8, wherein aligning the graft includes partially expanding the graft and rotating the graft, while partially expanded, about its longitudinal axis to align the one or more apertures of the graft with the one or more branch vessels, the apertures being defined in a sidewall of the graft.

11. A process of bridging a defect disposed in a main vessel near one or more branch vessels, comprising:

inserting, within the main vessel, a graft in a contracted state, the graft defining one or more apertures;

aligning the graft within the main vessel such that each aperture aligns with at least a respective one of the branch vessels; and

expanding the graft to an expanded state wherein the one or more apertures are aligned with the one or more branch vessels and the graft presses against a wall of the main vessel;

wherein aligning the graft includes partially expanding the graft and aligning the graft while partially expanded;

wherein partially expanding the graft includes heating the stent to a temperature between an austenite start temperature and an austenite finish temperature of the graft.

12. The process of claim 11, wherein aligning includes using three-dimensional imaging.

13. The process of claim 11, wherein aligning the graft includes partially expanding the graft and rotating the graft, while partially expanded, about its longitudinal axis to align the one or more apertures of the graft with the one or more branch vessels, the apertures being defined in a sidewall the graft.

14. A stent-graft for bridging an aneurysm in an aorta, the aneurysm being at least partially disposed between two renal arteries and two iliac arteries, comprising:

a graft material defining at least one renal aperture oriented to align with one of the two renal arteries when the stent-graft is in an expanded state; and

a stent system for supporting the graft material in a contracted state wherein each renal aperture is contracted and the expanded state wherein each renal aperture is expanded;

further including a radiopaque marker surrounding the perimeter of a respective renal aperture.

15. A stent-graft for bridging an aneurysm in an aorta, the aneurysm being at least partially disposed between two renal arteries and two iliac arteries, comprising:

a graft material defining at least one renal aperture oriented to align with one of the two renal arteries when the stent-graft is in an expanded state; and

a stent system for supporting the graft material in a contracted state wherein each renal aperture is contracted and the expanded state wherein each renal aperture is expanded;

wherein each renal aperture is larger than the orifice of the respective renal artery.

16. A graft for bridging an aneurysm at least partially disposed in an aorta between two renal arteries and two iliac arteries, comprising:

graft material adapted to extend from above at least one of the two renal arteries to a region below the aneurysm without substantially extending into the either of the two renal arteries; and

at least one renal aperture defined by the graft material for aligning with a respective one of the two renal arteries; and

a stent system attached to the graft material;

wherein the graft material is adapted to expand from a contracted state wherein the at least one renal aperture is contracted and an expanded state wherein the at least one renal aperture is expanded and the graft material presses against a wall of the aorta;

wherein the at least one renal aperture, defines an opening larger than an orifice of the respective renal artery so as not to obstruct the respective renal artery when the graft material is in the expanded state.

17. The graft of claim 16, wherein the graft material defines a unitary tubular member adapted to extend from above at least one of the two renal arteries to the region below the aneurysm without substantially extending into the either of the two renal arteries.

18. The graft of claim 16, wherein the stent system further defines at least one aperture aligned with the at least one renal aperture defined by the graft material.

19. A stent-graft for bridging an aortic aneurysm at least partially disposed between two renal arteries and two iliac arteries, comprising:

a stent system; and

a unitary piece of graft material attached to the stent system and adapted to extend from above at least one of the two renal arteries to a location near the distal end of the aneurysm, the graft material defining at least one renal aperture for aligning with a respective one of the two renal arteries;

wherein the at least one renal aperture is contracted when the graft material is in a contracted state and wherein the at least one renal aperture is expanded when the graft material is an expanded state;

wherein the at least one renal aperture in the expanded state defines an opening larger than an orifice of the respective one of the two renal arteries.

20. The stent-graft of claim 19, wherein the at least one renal aperture includes a single renal aperture and the unitary piece of graft material includes a first end adapted to be located between the two renal arteries and a second end adapted to be located near the distal end of the aneurysm.

21. The stent-graft of claim 19, wherein the at least one renal aperture includes two renal apertures and the unitary piece of graft material is adapted to extend from a location above the two renal arteries to the location near the distal region of the aneurysm.

22. The stent-graft of claim 19, wherein the stent system includes at least one supporting portion attached to the graft material surrounding the perimeter of the at least one renal aperture.

23. The graft of claim 19, wherein the unitary piece of graft material is adapted to extend from above at least one of the two renal arteries to the location near the distal end of the aneurysm without substantially extending into the either of the two renal arteries.