Implantable medical device with optimized shape

• US 20050228472A1
• Filed: 04/06/2005
• Published: 10/13/2005
• Est. Priority Date: 04/08/2004
• Status: Active Grant

• Current Assignee: Cook Medical Incorporated (Cook Group Incorporated)
• Original Assignee: Cook Incorporated (Cook Group Incorporated)
• Inventors: Case, Brian C., Flagle, Jacob A.
• Granted Patent: US 7,637,937 B2
• Time in Patent Office: Days
• US Class Current: 623/1.100
• CPC Class Codes: A61F 2/2418 Scaffolds therefor, e.g. support stents
• CPC Class Codes: A61F 2/2475 Venous valves
• CPC Class Codes: A61F 2/90 characterised by a net-like or mesh-like structure
• CPC Class Codes: A61F 2002/30014 differing in elasticity, stiffness or compressibility
• CPC Class Codes: A61F 2002/3011 Cross-sections or two-dimensional shapes
• CPC Class Codes: A61F 2220/0016 with sharp anchoring protrusions, e.g. barbs, pins, spikes
• CPC Class Codes: A61F 2220/005 using adhesives
• CPC Class Codes: A61F 2220/0058 soldered or brazed or welded
• CPC Class Codes: A61F 2230/0002 Two-dimensional shapes, e.g. cross-sections
• CPC Class Codes: A61F 2230/0017 Angular shapes
• CPC Class Codes: A61F 2230/0054 V-shaped
• CPC Class Codes: A61F 2250/0018 differing in elasticity, stiffness or compressibility
• CPC Class Codes: A61F 2250/0036 differing in thickness

Abstract

Medical devices for implantation in a body vessel, and methods of using and making the same, are provided. Embodiments of the invention relate to medical devices comprising a frame having cross-section that can substantially conform to body vessel shapes that have elliptical or circular cross-sections, and dynamically respond to changes in the cross-section of a body vessel. Frames with directionally-dependent radial compressibility or expandability characteristics are also provided. Medical devices comprising a frame and one or more valve members adapted to regulate fluid flow in a body vessel, such as a vein, are also provided.

Claims

1. A medical device for implantation in a body vessel, comprising:

a frame having a longitudinal axis, and a first radial compressibility along a first radial direction that is less than a second radial compressibility along a second radial direction.

2. The medical device of claim 1, wherein

(a) the first radial direction is substantially perpendicular to the longitudinal axis;

and

(b) the second radial direction is substantially perpendicular to the longitudinal axis.

3. The medical device of claim 1, wherein the first radial direction is substantially perpendicular to the second radial direction.

4. The medical device of claim 1, wherein the medical device has a compressed configuration and an expanded configuration.

5. The medical device of claim 1, further comprising a means for regulating fluid flow through a body vessel.

6. The medical device of claim 1, wherein the frame comprises a cross-section having a first maximum radial distance along the first radial direction that is greater than a second maximum radial distance along the second radial direction.

7. The medical device of claim 1, wherein the medical device further comprises a means for orienting the medical device within a body vessel.

8. The medical device of claim 1, wherein the frame has a tubular configuration defining a lumen;

the frame being moveable between a compressed configuration defining a first lumen with a circular cross section, and an expanded configuration defining a second lumen with an elliptical cross section.

9. The medical device of claim 1, wherein the frame comprises an elliptical annular ring member comprising a plurality of struts.

10. The medical device of claim 9 wherein the frame comprises a first region joined to a second region,

(a) the first region having a first strut density per unit of circumferential distance, intersecting the first radial direction;

and

(b) a second region having a second strut density per unit of circumferential distance, intersecting the second radial direction, that is less than the first strut density.

11. The medical device of claim 9 wherein the frame comprises a first region joined to a second region;

(a) the first region having struts with a first strut cross-sectional area; and

(b) the second region having struts with a second strut cross-sectional area that is less than the first strut cross-sectional area.

17. The medical device of claim 1, where the frame comprises a material selected from the group consisting of:

a stainless steel, a NiTi alloy and a cobalt-chromium alloy.

18. The medical device for of claim 1, where the frame is expandable from a compressed configuration to an expanded configuration;

and where;

(a) the frame exerts a first radial expansion force along a first radial direction that is less than a second radial expansion force along a second radial direction during expansion,

(b) the first radial direction is substantially perpendicular to the longitudinal axis; and

(c) the second radial direction is substantially perpendicular to the longitudinal axis.

12. A medical device for implantation in a body vessel, comprising:

a frame having a longitudinal axis, and a first radial expandibility along a first radial direction, that is less than a second radial expandibility along a second radial direction, and

(a) the first radial direction is substantially perpendicular to the longitudinal axis; and

(b) the second radial direction is substantially perpendicular to the longitudinal axis.

13. The medical device of claim 12, wherein the medical device further comprises a means for regulating fluid flow through a body vessel.

14. The medical device of claim 12, wherein the medical device is moveable from a compressed configuration with a circular cross section to an expanded configuration with an elliptical cross section.

15. The medical device of claim 12, wherein the frame is further characterized by a first radial compressibility along the first radial direction, that is less than a second radial compressibility along the second radial direction, and where the first radial expandibility is substantially the same as the first radial compressibility;

and wherein the second radial expandibility is substantially the same as the second radial compressibility.

16. The medical device of claim 12, where the medical device frame has a first radial compressibility along a first radial direction that is less than a second radial compressibility along a second radial direction, and where the first radial direction is substantially perpendicular to the longitudinal axis;

and the second radial direction is substantially perpendicular to the longitudinal axis; and

where the medical further comprises a first valve member connected to the frame, the valve member comprising a valve member responsive to the flow of fluid through a body vessel, the valve member being adapted to permit fluid flow through said vessel in a first direction and substantially prevent fluid flow through said vessel in a second, opposite direction.

19. A method of making a medical device for implantation in a body vessel, comprising the step of attaching a first valve member to a frame,

(a) the valve member comprising a valve member responsive to the flow of fluid through the frame, the valve member permitting fluid flow through said vessel in a first direction and substantially preventing fluid flow through said vessel in a second, opposite direction;

and

(b) the frame having a longitudinal axis, and a first radial compressibility along a first radial direction, that is less than a second radial compressibility along a second radial direction, and

(c) the first radial direction is substantially perpendicular to the longitudinal axis; and

(d) the second radial direction is substantially perpendicular to the longitudinal axis.

20. A method of treating a subject, comprising the step of:

delivering the medical device to a point of treatment in a body vessel;

the medical device comprising;

(a) a frame having a longitudinal axis, and a first radial compressibility along a first radial direction that is less than a second radial compressibility along a second radial direction, and

(1) the first radial direction is substantially perpendicular to the longitudinal axis; and

(2) the second radial direction is substantially perpendicular to the longitudinal axis; and

(b) a first valve member attached to the frame, the valve member comprising a valve member responsive to the flow of fluid through the frame, the valve member being adapted to permit fluid flow through said vessel in a first direction and substantially prevent fluid flow through said vessel in a second, opposite direction.