STENT FOR VALVE REPLACEMENT

• US 20120035702A1
• Filed: 04/23/2010
• Published: 02/09/2012
• Est. Priority Date: 04/24/2009
• Status: Abandoned Application

• Current Assignee: United States Secretary of Health and Human Services is the head of the United States Department of Health and Human Services
• Original Assignee: United States Secretary of Health and Human Services is the head of the United States Department of Health and Human Services
• Inventors: Mazilu, Dumitru, Horvath, Keith, Li, Ming
• Application Number:
  US13/265,315
• Publication Number:
  US 20120035702A1
• Time in Patent Office: Days
• US Class Current: 623/1.11
• CPC Class Codes: A61F 2/2418 Scaffolds therefor, e.g. support stents
• CPC Class Codes: A61F 2/2433 using balloon catheter
• CPC Class Codes: A61F 2/2436 Deployment by retracting a sheath
• CPC Class Codes: A61F 2220/0008 Fixation appliances for connecting prostheses to the body
• CPC Class Codes: A61F 2230/0054 V-shaped

Abstract

An expandable stent (12) for use in the implantation of a valve prosthesis (11) using a delivery system (10) is disclosed. The self-expandable stent (12) includes a tubular lattice structure (13) defined by longitudinally aligned rods (16) connected to V- shaped struts (17) for forming a plurality of interconnected chevron-shaped six-sided polygons (24) that define a distal end zone (21) and a middle zone (20) of the tubular lattice structure (13). A flare (27) or bend may be defined along opposite ends of each rod (16) to properly seat and prevent undue torsion of the stent (12) and valve prosthesis (11) during deployment and placement of the stent (12) within the lumen.

Claims

1. A stent (12A) comprising:

a tubular lattice structure (13) having a radial direction and a longitudinal direction, the tubular lattice structure (13) comprising;

a middle zone (20) in communication with a distal end zone (21), the middle zone (20) and distal end zone (21) including a plurality of rods (16) positioned substantially in the longitudinal direction of the tubular lattice structure (13) and interconnected by a plurality of struts (17) that collectively define a plurality of six-sided polygons (18).

2. The stent (12A) of claim 1, wherein each of the plurality of struts (17) defines an apex (17A) that is oriented towards the proximal end zone (19).

3. The stent (12) of claim 1, wherein the tubular lattice structure (13) further comprises a proximal end zone (19) in communication with the middle end zone (13), wherein the proximal end zone (19) includes a plurality of interconnected four-sided polygons (18).

4. The stent of (12A) claim 1, wherein the tubular lattice structure (13) is collapsible and expandable.

5. The stent (12A) of claim 4, wherein the tubular lattice structure (13) assumes a collapsed form from a fully expanded form when being placed in a constrained position and from the collapsed form to an expanded form after deployment.

6. The stent (12A) of claim 5, wherein the tubular lattice structure (13) has substantially the same longitudinal length in the collapsed form and in the expanded form.

7. The stent (12A) of claim 1, wherein the tubular lattice structure (13) is formed from at least one shape memory alloy.

8. The stent (12A) of claim 1, wherein the stent further comprises at least one marker affixed to the tubular lattice structure (13).

9. The stent (12A) of claim 1, wherein the tubular lattice structure (13) further comprises a grasping member (34) connected to at least one of the plurality of rods (16).

10. The stent (12A) of claim 1, wherein each of the plurality of rods (16) defines a first end (32) and a second end with each of the first and second ends defining a flare.

11. The stent (12A) of claim 10, wherein the first end (33) of each of the plurality of rods (16) is connected to one of the four-sided polygons (18) of the proximal end zone (19) and the second end (33) of each of the plurality of rods (16) forms a part of the distal end zone (21).

12. The stent (12A) of claim 1, further comprising a prosthesis (11) disposed inside the tubular lattice structure (13) of the stent (12).

13. The stent (12) of claim 1, wherein the stent (12) further comprises a protective insulated coating.

14. The stent (12A) of claim 12, where the prosthesis (11) includes a plurality of commissures (30), and wherein the prosthesis (11) is disposed and oriented inside the tubular lattice structure (13) such that each respective plurality of commissures (30) are aligned with at least one of the plurality of rods (16).

15. The stent (12A) of claim 1, wherein the tubular lattice structure (13) is formed from a group consisting of at least stainless steel, platinum/iridium, and magnesium.

16. A delivery system (10) comprising:

a hollow outer sheath (28) defining an opening (31);

a stent (12A) disposed adjacent the opening (31) of the hollow catheter sheath (28) and in a collapsed form, the stent (12A) including a tubular lattice structure (13) having a radial direction and a longitudinal direction, the tubular lattice structure (13) comprising;

a middle zone (20) in communication with a distal end zone (21), the middle zone (20) and distal end zone (21) including a plurality of rods (16) positioned substantially in the longitudinal direction of the tubular lattice structure (13) and interconnected by a plurality of struts (17) that collectively define a plurality of six-sided polygons; and

a valve prosthesis (11) disposed inside the tubular lattice structure (13) of the stent (12A).

17. The delivery system (10) of claim 16, wherein the tubular lattice structure (13) further comprises:

a proximal end zone (19) in communication with the middle end zone (13), wherein the proximal end zone (19) includes a plurality of interconnected four-sided polygons (18).

18. The delivery system (10) of claim 16, further comprising a marker (25, 29) affixed to the tubular lattice structure (13) for providing a visual indicator as to the location of the stent (12A).

19. The delivery system (10) of claim 18, wherein the marker (25, 29) is a passive marker (25).

20. The delivery system (10) of claim 18, wherein the marker (25, 29) is an active marker (29).

21. The delivery system (10) of claim 17, wherein the hollow outer sheath (28) is retractable for deploying the stent (12A).

22. A method for delivering and repositioning a stent (12A) in a lumen comprising:

providing a stent (12A) including a tubular lattice structure (13) having a radial direction and a longitudinal direction, the tubular lattice structure (13) comprising;

a middle zone (20) in communication with a distal end zone (21), the middle zone (20) and distal end zone (21) including a plurality of rods (16) positioned substantially in the longitudinal direction of the tubular lattice structure (13) and interconnected by a plurality of struts (17) that collectively define a plurality of six-sided polygon (18) in a delivery system (10), the delivery system (10) having a hollow, retractable hollow outer sheath (28) defining an opening (31) with the stent (12A) disposed therein adjacent the opening (31);

constraining the stent (12A) in a collapsed form within a delivery system (10) including a hollow outer sheath (28) adapted to receive the stent (12A) therein in the collapsed form;

delivering the stent (12A) percutaneously to a location in a lumen that requires repair or replacement;

retracting the outer sheath (28) of the deployment system (10) relative to the stent (12A) and permitting the stent (12A) to expand from the collapsed form to an expanded form in the location; and

monitoring an orientation and the location of the stent (12A) in the lumen.

23. The method of claim 22, wherein the stent (12A) includes a marker (25, 29) and further comprising:

repositioning the stent (12) using the marker (25, 29) to visually indicate the position of the stent (12) within the lumen.

24. The method of claim 22, wherein the tubular lattice structure (13) further comprises:

a proximal end zone (19) in communication with the middle end zone (20), wherein the proximal end zone (19) includes a plurality of interconnected four-sided polygons (18).

25. The method of claim 22, wherein one or more grasping members (34) are affixed to the tubular lattice structure (13) for manipulation by the delivery system (10).