Medical device having magnetically expandable frame

• US 9,526,639 B2
• Filed: 05/11/2015
• Issued: 12/27/2016
• Est. Priority Date: 05/13/2014
• Status: Active Grant

• Current Assignee: Cook Medical Technologies, LLC (Cook Group Incorporated)
• Original Assignee: Cook Medical Technologies, LLC (Cook Group Incorporated)
• Inventors: Hansen, Palle M., Andersen, Torben P.
• Primary Examiner(s): DUKERT, BRIAN AINSLEY
• Application Number:
  US14/709,067
• Publication Number:
  US 20150328022A1
• Time in Patent Office: 596 Days
• US Class Current: 1/1
• CPC Class Codes: A61B 17/12022 Occluding by internal devices, e.g. balloons or releasable wires plugging an opening in the wall of an organ A61B17/0057; occluders for the cervical canal A61F6/146; vas deferens occluders A61F6/20
• CPC Class Codes: A61F 2/0105 Open ended, i.e. legs gathered only at one side
• CPC Class Codes: A61F 2/844 folded prior to deployment
• CPC Class Codes: A61F 2/90 characterised by a net-like or mesh-like structure
• CPC Class Codes: A61F 2/915 with bands having a meander structure, adjacent bands being connected to each other
• CPC Class Codes: A61F 2002/016 made from wire-like elements
• CPC Class Codes: A61F 2002/018 made from tubes or sheets of material, e.g. by etching or laser-cutting
• CPC Class Codes: A61F 2210/009 magnetic

Abstract

A stent, for example, is provided with a plurality of frame elements, which may have an undulating form. The stent is provided with a plurality of magnetic elements between adjacent stent elements. The magnetic elements on opposing circumferentially facing portions or sides of the strut elements have the same polarities so as to produce repulsive forces biasing the stent structure into a radially expanded configuration. The magnetic elements provide an alternative opening force on the stent, enabling the stent to be made of struts of thinner and weaker material or of a non-sprung material. The magnetic elements also provide a constant opening force in order to retain the stent reliably in position within a vessel. The stent could be made of a biodegradable material.

Claims

1. A medical device adapted to generate a magnetic repulsive force, the medical device comprising:

a support structure having a circumferential periphery extending in a circumferential direction, the support structure including a plurality of interconnected strut elements extending at least partially along a longitudinal axis, the longitudinal axis being normal to the circumferential direction, the strut elements being movable relative to one another in the circumferential direction; and

a plurality of magnetic elements, each magnetic element having a polar axis extending from a first pole to a second pole, the magnetic elements disposed on the strut elements such that the polar axis of each magnetic element follows the circumferential periphery of the support structure, wherein a circumferentially facing side of each strut element is provided with a first region of first magnetic polarity and an opposing circumferentially facing side of an adjacent strut element to the circumferentially facing side of each strut element is provided with a second region of first magnetic polarity so as to generate the magnetic repulsive force between adjacent strut elements, said magnetic repulsive force acting to bias the strut elements away from one another in the circumferential direction.

2. A medical device according to claim 1, wherein the medical device is implantable.

3. A medical device according to claim 2, wherein the medical device includes a stent.

4. A medical device according to claim 1, wherein the support structure is made from a polymer material.

5. A medical device according to claim 1, wherein the strut elements are interconnected at a plurality of connection points, and wherein the first magnetic polarity is provided on the circumferentially facing side of each strut element and the first magnetic polarity is provided on the opposing circumferentially facing side of an adjacent strut element along the longitudinal axis.

6. A medical device according to claim 1, wherein the magnetic elements are spheroids, rings, rods or rectangular cuboids.

7. A medical device according to claim 1, wherein the strut elements comprise the magnetic elements.

8. A medical device according to claim 1, wherein the magnetic elements are formed from paramagnetic material.

9. A medical device according to claim 1, wherein the magnetic elements are permanent magnets.

10. A medical device according to claim 1, wherein the strut elements are arranged in an alternating pattern of coupling to and separation of adjacent strut elements, defining a pair of elongate elements having a plurality of troughs and a plurality of apices.

11. A medical device according to claim 10, wherein the pair of elongate elements comprises a first element and a second element, the first element having a first strut end, the second element having a second strut end, the first strut end being connected to the second strut end.

12. A medical device according to claim 1, wherein the strut elements are arranged to form an array of rhombi.

13. A medical device according to claim 10, wherein the strut elements are interconnected at a plurality of connection points, wherein the magnetic elements are disposed at the connection points.

14. A medical device according to claim 12, wherein the magnetic elements comprise magnetic or paramagnetic material, the magnetic or paramagnetic material having a same magnetic polarity within a given rhombus of the array.

15. A medical device according to claim 1, further comprising a filter or occluding barrier disposed on the support structure.

16. A medical device according to claim 13 wherein the magnetic elements form the connection points.

17. A medical device according to claim 1 wherein the circumferentially facing side of each strut element comprises a third region of second magnetic polarity, the third region of second magnetic polarity being oppositely disposed from the first region of first magnetic polarity.

18. A medical device according to claim 17 wherein the first magnetic polarity is one of a north polarity and a south polarity.

19. A medical device according to claim 18 wherein the second magnetic polarity is the other of the north polarity and the south polarity.

20. A medical device according to claim 14 wherein the magnetic elements comprise a polymer coating.