Implantable Medical Device

• US 20110040369A1
• Filed: 08/03/2010
• Published: 02/17/2011
• Est. Priority Date: 08/11/2009
• Status: Abandoned Application

• Current Assignee: Cook Medical Incorporated (Cook Group Incorporated)
• Original Assignee: Cook Incorporated (Cook Group Incorporated), William Cook Europe ApS (Cook Group Incorporated)
• Inventors: Ohlenschlager, Bent, Jensen, Kim Moegelvang, Petersen, Jesper Schade, Rasmussen, Erik
• Application Number:
  US12/849,470
• Publication Number:
  US 20110040369A1
• Time in Patent Office: Days
• US Class Current: 623/1.13
• CPC Class Codes: A61F 2/07 Stent-grafts
• CPC Class Codes: A61F 2/844 folded prior to deployment
• 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 2/89 the wire-like elements comprising two or more adjacent rings flexibly connected by separate members
• CPC Class Codes: A61F 2/90 characterised by a net-like or mesh-like structure
• CPC Class Codes: A61F 2002/075 the stent being loosely attached to the graft material, e.g. by stitching
• CPC Class Codes: A61F 2002/8483 Barbs
• CPC Class Codes: A61F 2210/0014 using shape memory or superelastic materials, e.g. nitinol
• CPC Class Codes: A61F 2220/0058 soldered or brazed or welded
• CPC Class Codes: A61F 2220/0075 sutured, ligatured or stitched, retained or tied with a rope, string, thread, wire or cable
• CPC Class Codes: A61F 2310/00023 Titanium or titanium-based alloys, e.g. Ti-Ni alloys

Abstract

A stent graft (10) includes a tubular graft element (12) to which there are attached a plurality of stent rings (14). The stent rings (14) are formed of a plurality of stent struts (16) arranged in a zig-zag arrangement with alternating peaks (18) and valleys (20). The end-most stent (22) is located at the proximal end (24) of the graft tube (12). Between adjacent peaks (18) of the end-most stent (22), there is provided a series of bridging elements (28). These are preferably formed of Nitinol wire and to be substantially more flexible than the stent struts (14). The bridging elements (28) extend in the region of graft material between adjacent stent peaks (18) and are attached to the graft material, for example by suturing. The bridging elements (28) are substantially more flexible than the stent ring (22) and therefore impart little opening force on the graft material in comparison to the force produced by the stent ring (22). However, the bridging elements (28) impart enough force on the flaps (26) of graft material between the peaks (18) of the stent ring (28) keep these flaps (26) open, that is against the vessel wall. The bridging elements (28) can provide integral barbs (30).

Claims

1. An implantable medical device including:

a tubular graft member;

at least one stent provided on the graft member proximate an end thereof, wherein the stent is formed of a plurality of struts coupled together at their ends in the form of a stent ring having peaks and valleys, the struts of the stent being formed of a flexible material to allow the stent to be compressed and to expand, wherein the struts have a first flexibility; and

a plurality of bridging elements located between adjacent peaks formed by the struts of said stent, said bridging elements being coupled to the struts and extending towards and proximate said end of said graft element;

said bridging elements having a second flexibility, wherein second flexibility is greater than said first flexibility;

wherein said bridging elements produce in use an expansion force urging graft material of said graft element in a graft opening direction, wherein the opening force produced by said bridging elements is less than an opening force produced by said stent ring.

2. An implantable medical device according to claim 1, wherein said bridging elements are located within the extent of the graft member.

3. An implantable medical device according to claim 1, wherein the opening force produced by said bridging elements is between 10% to 75% of the opening force produced by said stent ring.

4. An implantable medical device according to claim 1, wherein the opening force produced by said bridging elements is in the region of 50% of the opening force produced by the stent ring.

5. An implantable medical device according to claim 1, wherein said bridging elements have a transverse cross-sectional area of 10% to 75% of the cross-sectional area of the associated stent struts.

6. An implantable medical device according to claim 1, wherein said bridging elements have a transverse cross-sectional area of around 10% -75% of the thickness of the struts forming said stent ring.

7. An implantable medical device according to claim 1, wherein said bridging elements are formed from a length of wire.

8. An implantable medical device according to claim 7, wherein said bridging elements are coupled to said stent by wrapping said wire around said stent struts.

9. An implantable medical device according to claim 8, wherein said bridging elements are wrapped around adjacent struts of said stent ring.

10. An implantable medical device according to claim 1, wherein said bridging elements are provided with at least one barb element.

11. An implantable medical device according to claim 10, where each bridging element includes two barb structures.

12. An implantable medical device as specified in claim 7, wherein said bridging elements are coupled to said graft member by at least one suture.

13. An implantable medical device according to claim 1, wherein said bridging elements are formed from shape memory material.

14. An implantable medical device according to claim 13, wherein said bridging elements are formed from Nitinol.

15. An implantable medical device according to claim 2, wherein said bridging elements have a transverse cross-sectional area of around 10%-75% of the thickness of the struts forming said stent ring.

16. An implantable medical device according to claim 3, wherein said bridging elements have a transverse cross-sectional area of around 10%-75% of the thickness of the struts forming said stent ring.

17. An implantable medical device according to claim 4, wherein said bridging elements have a transverse cross-sectional area of around 10%-75% of the thickness of the struts forming said stent ring.

18. An implantable medical device according to claim 5, wherein said bridging elements have a transverse cross-sectional area of around 10%-75% of the thickness of the struts forming said stent ring.