Prosthetic venous valves

• US 7,744,642 B2
• Filed: 11/18/2005
• Issued: 06/29/2010
• Est. Priority Date: 11/19/2004
• Status: Active Grant

• Current Assignee: Biomedical Research Associates Incorporated, University of Akron
• Original Assignee: Biomedical Research Associates Incorporated, University of Akron
• Inventors: Evancho-Chapman, M. Michelle, Lopina, Stephanie T., Oberdier, Matthew T., Rittgers, Stanley E., Schmidt, Steven P.
• Primary Examiner(s): Willse; David H
• Assistant Examiner(s): WOLF, MEGAN YARNALL
• Application Number:
  US11/282,515
• Publication Number:
  US 20060111773A1
• Time in Patent Office: 1,684 Days
• Field of Search: 623 124- 126, 623 212- 219, 623/2.1, 623 22- 233, 623/217
• US Class Current: 623/1.24
• CPC Class Codes: A61F 2/2409 Support rings therefor, e.g. for connecting valves to tissue annuloplasty rings A61F2/2442
• CPC Class Codes: A61F 2/2412 with soft flexible valve members, e.g. tissue valves shaped like natural valves check valves with flexible valve members in general F16K15/14
• CPC Class Codes: A61F 2/2418 Scaffolds therefor, e.g. support stents
• CPC Class Codes: A61F 2/2475 Venous valves
• CPC Class Codes: A61F 2220/0008 Fixation appliances for connecting prostheses to the body
• CPC Class Codes: A61F 2220/005 using adhesives
• CPC Class Codes: A61F 2230/0008 elliptical or oval
• CPC Class Codes: A61F 2230/001 Figure-8-shaped, e.g. hourglass-shaped
• CPC Class Codes: B33Y 80/00 Products made by additive manufacturing

Abstract

A prosthetic venous valve includes a frame and leaflets. The frame includes: (i) a generally hollow base disposed at a blood inflow end; (ii) a plurality of struts connected with the base and extending generally parallel to a direction of forward flow of blood from the generally hollow base to a blood outflow end; and (iii) inwardly oriented flanges disposed at the blood outflow ends of the struts. The leaflets are disposed in gaps between the struts and are supported by the frame. The leaflets are arranged to close into the vein lumen to substantially seal against backflow of blood from the blood outflow end to the blood inflow end. The inwardly oriented flanges of the struts enhance the sealing.

Claims

1. A prosthetic venous valve comprising:

a frame sized and configured to be implanted in a vein to replace a venous valve and including (i) a generally hollow base disposed at a blood inflow end, (ii) a plurality of struts connected with the base and extending generally parallel to a direction of forward flow of blood from the generally hollow base to a blood outflow end, and (iii) inwardly oriented flanges disposed at the blood outflow ends of the struts, the inwardly oriented flanges extending inwardly toward the center of the vein lumen; and

leaflets disposed in gaps between the struts and supported by the frame, the leaflets having free edges arranged to close into the vein lumen and meet to substantially seal against backflow of blood from the blood outflow end to the blood inflow end, the inwardly oriented flanges of the struts having curved surfaces configured to mate with proximate portions of the free edges of the leaflets to ensure sealing of the valve in the closed position substantially without buckling or pleating of the free edges of the leaflets;

wherein the curved surfaces of the inwardly oriented flanges of the struts include at least one of (i) curved surface portions having a constant radius of curvature and (ii) a semicircular portion continuing into a quarter-circular portion.

2. The prosthetic venous valve as set forth in claim 1, wherein the leaflets have curved free edges at the blood outflow end that are shaped relatively higher distal from the struts and relatively lower proximate to the struts to contact the curved surfaces of the inwardly oriented flanges and to contact each other along a cross-sectional plane in the closed position.

3. The prosthetic venous valve as set forth in claim 1, wherein at least a portion of the frame is partially hollowed out to define a cavity containing at least one drug, the cavity having orifices that are small compared with the cavity and that include rate-limiting plugs of a material through which the drug diffuses at a known rate to provide release of the drug from the cavity at a controlled rate.

4. The prosthetic venous valve as set forth in claim 3, wherein the drug comprises an anti-thrombotic or anti-proliferative agent.

5. The prosthetic venous valve as set forth in claim 3, wherein the orifices including rate limiting plugs are disposed on the struts to release the drug from the cavity locally near the struts.

6. The prosthetic venous valve as set forth in claim 1, wherein the leaflets comprise a generally tubular leaflets member that is tapered such that a cross-sectional dimension of the generally tubular leaflets members at the blood outflow end in the open position is smaller than or about 85% of a corresponding cross-sectional dimension of the generally tubular leaflets members at the blood inflow end.

7. The prosthetic venous valve as set forth in claim 6, wherein the tapering of the generally tubular leaflets member comprises:

a narrowing of a diameter of the generally tubular leaflets member from the blood inflow end to the blood outflow end such that the diameter at the blood outflow end is between about 70% and 85% of the diameter at the blood inflow end.

8. The prosthetic venous valve as set forth in claim 1, wherein each leaflet in the open position has a monotonically increasing longitudinal extent along a path starting at one of the two supporting neighboring struts and ending midway between the two supporting neighboring struts.

9. The prosthetic venous valve as set forth in claim 1, wherein the plurality of struts consists of two struts, and the plurality of leaflets consists of two leaflets.

10. The prosthetic venous valve as set forth in claim 9, wherein the two leaflets have free edges shaped to meet in a straight line along a diameter between the two struts in the closed position.

11. The prosthetic venous valve as set forth in claim 1, wherein the leaflets are wrapped around the outside of the plurality of struts.

12. The prosthetic venous valve as set forth in claim 1, wherein the leaflets are flexible leaflets.

13. A prosthetic venous valve comprising:

a frame sized and configured to be implanted in a vein to replace a venous valve and including (i) a generally hollow base disposed at a blood inflow end, (ii) a plurality of struts connected with the base and extending generally parallel to a direction of forward flow of blood from the generally hollow base to a blood outflow end, and (iii) inwardly oriented flanges disposed at the blood outflow ends of the struts, the inwardly oriented flanges extending inwardly toward the center of the vein lumen; and

leaflets disposed in gaps between the struts and supported by the frame, the leaflets having free edges arranged to close into the vein lumen and meet to substantially seal against backflow of blood from the blood outflow end to the blood inflow end, the inwardly oriented flanges of the struts having curved surfaces configured to mate with proximate portions of the free edges of the leaflets to ensure sealing of the valve in the closed position substantially without buckling or pleating of the free edges of the leaflets;

wherein the curved surfaces of the inwardly oriented flanges of the struts include curved surface portions having a constant radius of curvature.

14. The prosthetic venous valve as set forth in claim 13, wherein the leaflets are wrapped around the outside of the plurality of struts.

15. The prosthetic venous valve as set forth in claim 13, wherein the leaflets are flexible leaflets.

16. A prosthetic venous valve comprising:

a frame sized and configured to be implanted in a vein to replace a venous valve and including (i) a generally hollow base disposed at a blood inflow end, (ii) a plurality of struts connected with the base and extending generally parallel to a direction of forward flow of blood from the generally hollow base to a blood outflow end, and (iii) inwardly oriented flanges disposed at the blood outflow ends of the struts, the inwardly oriented flanges extending inwardly toward the center of the vein lumen; and

leaflets disposed in gaps between the struts and supported by the frame, the leaflets having free edges arranged to close into the vein lumen and meet to substantially seal against backflow of blood from the blood outflow end to the blood inflow end, the inwardly oriented flanges of the struts having curved surfaces configured to mate with proximate portions of the free edges of the leaflets to ensure sealing of the valve in the closed position substantially without buckling or pleating of the free edges of the leaflets;

wherein the curved surfaces of the inwardly oriented flanges of the struts include a semicircular portion continuing into a quarter-circular portion.