STENT AND STENT GRAFT PROSTHESIS

• US 20140121761A1
• Filed: 06/01/2012
• Published: 05/01/2014
• Est. Priority Date: 06/03/2011
• Status: Active Grant

• Current Assignee: Vascutek Limited (Terumo Corporation)
• Original Assignee: Vascutek Limited (Terumo Corporation)
• Inventors: McDonald, Gary Peter, Nelis, Vincent
• Granted Patent: US 9,993,329 B2
• Time in Patent Office: Days
• US Class Current: 623/1.16
• CPC Class Codes: A61F 2/07 Stent-grafts
• CPC Class Codes: A61F 2/89 the wire-like elements comprising two or more adjacent rings flexibly connected by separate members
• CPC Class Codes: A61F 2002/075 the stent being loosely attached to the graft material, e.g. by stitching
• CPC Class Codes: A61F 2230/0095 Saddle-shaped

Abstract

There is provided a stent member a plurality of spaced stent elements for location on a tubular graft, wherein a first stent element is located in a first location on said graft, and wherein a second stent element is located in a second location or said graft, and wherein the second stent element comprises a saddle shaped stent. The first stent element includes a ring shaped (circular) stent. The second stent element includes at least one, preferably 2 to 5, saddle shaped stents. Optionally a third stent element comprising from 1 to 10 saddle shaped stents is also present. The stents are typically form a continuous loop of an elongate member of resilient material such as nitinol or PEEK. A stent graft comprising a tubular sleeve to which the stent member is attached is also described, as is the use of the prosthesis for treatment of vascular disorders such as aortic aneurysm.

Claims

1. A stent member comprising a plurality of spaced stent elements for location on a tubular graft, wherein a first stent element is located in a first location on said graft, and wherein a second stent element is located in a second location on said graft, and wherein the second stent element comprises a saddle shaped stent.

2. The stent member as claimed in claim 1 wherein the first location is at or close to one end of the tubular graft.

3. The stent member as claimed in claim 1 wherein the first stent element is ring shaped and has an inner circumference substantially identical to the outer circumference of the tubular graft.

4. The stent member as claimed in claim 1 further comprising a third stent element having at least one stent with a saddle shape different to that of each stent in the second stent element.

5. The stent member as claimed in claim 4 wherein the third stent element comprises a stent which has a saddle shape with a greater degree of axial displacement relative to the saddle shape of at least one stent of the second stent element.

6. The stent member as claimed in claim 1 wherein the first stent element comprises:

i) a terminal stent formed from a continuous loop of resilient material in a saddle-shape; and

ii) a second stent formed in a continuous loop and in circular form with an inner circumference substantially identical to the outer circumference of the graft sleeve.

7. The stent member as claimed in claim 6 wherein the second stent of the first stent element has a saddle height of from 4 to 8 mm.

8. The stent member as claimed in claim 1 wherein the second stent element comprises a saddle shaped stent having a first saddle height and a saddle shaped stent having a second saddle height which is different to the first saddle height.

9. The stent member as claimed in claim 8 wherein the first saddle height is from 4 to 8 mm and the second saddle height is from 8 to 15 mm.

10. The stent member as claimed in claim 4 wherein the saddle height of each saddle shaped stent of the third stent element is independently selected from 10 to 25 mm.

11. The stent member as claimed in claim 4, wherein any of the stents in the first stent element, second stent element and/or third stent element are formed from multiple windings of nitinol wire.

12. The stent member as claimed in claim 4, wherein any of the stents in the first stent element, second stent element and/or third stent element are formed from a resilient polymer.

13. The stent member as claimed in claim 12 wherein said resilient polymer is polyether ether ketone.

14. A stent graft prosthesis comprising a tubular graft sleeve and a stent member as claimed in claim 1.

15. A stent graft prosthesis, said prosthesis having a tubular graft, a first stent element attached to the tubular graft, a second stent element attached the tubular graft, and a third stent element attached the tubular graft, wherein:

the first stent element comprises a stent which is a substantially circular ring stent;

the second stent element comprises at least one ring stent which has an oversize of 2 to 25% and which is arranged in a saddle shape; and

the third stent element comprises at least one ring stent which has an oversize of 20 to 30% and which is arranged in a saddle shape.

16. The prosthesis as claimed in claim 15 wherein said second stent element comprises at least two ring stents each having an oversize of 2 to 25%.

17. The prosthesis as claimed in claim 16 wherein said second stent element comprises 3, 4 or 5 ring stents each having an oversize of 2 to 25%.

18. The prosthesis as claimed in claim 16 wherein each stent in the second stent element is attached to the graft so that the peaks and valleys are longitudinally aligned with the peaks and valleys of the other stents of the second stent element.

19. The prosthesis as claimed in claim 15, wherein the third stent element comprises at least four ring stents each having an oversize of 20 to 30%.

20. The prosthesis as claimed in claim 19 wherein said third stent element comprises 5 to 10 ring stents each having an oversize of 20 to 30%.

21. The prosthesis as claimed in claim 19 wherein each stent of the third stent element is attached to the graft so that the peaks and valley are longitudinally aligned with the peaks and valleys of the other stents of the third stent element.

22. The prosthesis as claimed in claim 15 further comprising a fourth stent element which comprises a circular ring stent.

23. The prosthesis as claimed in claim 22 wherein said fourth stent element further comprises a saddle shaped ring stent located adjacent the circular ring stent.

27. A method of treating an aneurysm of the aortic arch, said method comprising inserting a prosthesis as claimed in claim 15 such that the first stent element sealingly engages with the inner luminal wall of the aorta, the second stent element provides the flexibility able to accommodate the angulation associated with the descending thoracic arch, and the third stent element provides axial and torsional stiffness required to ensure the integrity of the graft within the aneurysm sac and/or within the longer straighter section of the descending aorta.

24. A stent graft prosthesis comprising:

i) a sleeve having a first end and a second end with a lumen extending therethrough;

ii) first, second and third stent elements attached to the sleeve a pre-selected distance apart;

wherein the first stent element comprises at least one ring stent having an inner circumference substantially identical to the outer circumference of the sleeve, wherein the second stent element comprises at least 2 saddle shaped stents wherein the saddle height is at least 5 mm, and wherein the third stent element comprises at least two saddle shaped stents wherein the saddle height is at least 10 mm.

25. The prosthesis as claimed in claim 24 wherein the pre-selected distance is the saddle height D.

30. A method of treating an aneurysm of the aortic arch, said method comprising inserting a prosthesis as claimed in claim 24 such that the first stent element sealingly engages with the inner luminal wall of the aorta, the second stent element provides the flexibility able to accommodate the angulation associated with the descending thoracic arch, and the third stent element provides axial and torsional stiffness required to ensure the integrity of the graft within the aneurysm sac and/or within the longer straighter section of the descending aorta.

26. An implantable prosthesis comprising:

i) a compliant and substantially fluid impervious tubular sleeve having a proximal end and a distal end with a conduit therethrough;

ii) a first stent element comprising at least one stent formed from multiple windings of wire of a shape memory material, attached to said sleeve at a first location thereon;

iii) a second stent element attached to said sleeve comprising at least two stents, each formed from multiple windings of wire of a shape memory material, each stent having a saddle shape configuration with two diametrically opposed peaks and two diametrically opposed valleys, the valleys being axially displaced relative to the peaks, wherein the peaks of each stent are aligned longitudinally; and

iv) a third stent element attached to said sleeve comprising at least two stents, each formed from multiple windings of wire of a shape memory material, each stent having a saddle shape configuration with two diametrically opposed peaks and two diametrically opposed valleys, the valleys being axially displaced relative to the peaks, wherein the peaks of each stent are aligned longitudinally, wherein each peak of each stent in the second stent element is longitudinally aligned with a peak of each stent in the third stent element, and wherein the axial displacement between the peaks and valleys of each stent in the third stent element is larger than the axial displacement between the peaks and valleys of each stent in the second stent element.

31. A method of treating an aneurysm of the aortic arch, said method comprising inserting a prosthesis as claimed in claim 26 such that the first stent element sealingly engages with the inner luminal wall of the aorta, the second stent element provides the flexibility able to accommodate the angulation associated with the descending thoracic arch, and the third stent element provides axial and torsional stiffness required to ensure the integrity of the graft within the aneurysm sac and/or within the longer straighter section of the descending aorta.

28. A method of treating a patient in need thereof, said method comprising implanting a prosthesis comprising a tubular graft, a first stent element attached to the tubular graft, a second stent element attached to the tubular graft and a third stent element attached to the tubular graft, wherein the first stent element comprises a substantially circular ring stent, the second stent element comprises at least one stent formed as a continuous loop and attached to the tubular graft in a saddle shape;

and the third stent element comprises at least one stent formed as a continuous loop and attached to the tubular graft in a saddle shape.

29. A method of manufacturing a prosthesis suitable for implantation into the body, said method comprising;

(i) providing a flexible tubular conduit;

(ii) providing a first stent element comprising a stent in the form of a continuous loop and attaching said stent to the conduit, so the stent describes a circumference of the tubular conduit;

(iii) providing a second stent element comprising a stent in the form of a continuous loop and attaching said stent to said tubular conduit so that the stent describes a first saddle shape having peaks and valleys;

(iv) providing a third stent element comprising a stent in the form of a continuous loop and attaching said stent to the tubular conduit such that the stent describes a second saddle shape having peaks and valleys aligned with the respective peaks and valley of the stent of the second stent element.