Repositionable endoluminal support structure and its applications
An endoluminal support structure includes strut members interconnected by swivel joints to form a series of linked scissor mechanisms. The structure can be remotely actuated to compress or expand its shape by adjusting the scissor joints within a range of motion. In particular, the support structure can be repositioned within the body lumen or retrieved from the lumen. The support structure can be employed to introduce and support a prosthetic valve within a body lumen.
1. A medical device configured for passage through a biological lumen of a patient, comprising:
a plurality of strut members, comprising:
discrete elongated inner strut members; and
discrete elongated outer strut members interlinked to the plurality of elongated inner strut members by a plurality of swivel joints to form a shaped structure comprising a compressed orientation and an expanded orientation;
wherein each inner strut member is interlinked with at least three outer strut members and none of the inner strut members are interlinked to another inner strut member; and
wherein each outer strut member is interlinked with at least three inner strut members and none of the outer strut members is interlinked to another outer strut member, and wherein at each swivel joint, the inner strut members are located closer to a central axis of the apparatus than the outer strut members.
2. The apparatus of claim 1 , further comprising an actuation mechanism to urge the swivel joints within a range of motion.
3. The apparatus of claim 1 , wherein a swivel joint forms a scissor mechanism with an inner strut member and an outer strut member.
4. The apparatus of claim 3 , wherein the inner strut members and the outer strut members are arranged as a series of linked scissor mechanisms.
5. The apparatus of claim 1 , further comprising a prosthetic valve coupled to the shaped structure.
6. The apparatus of claim 5 , wherein the prosthetic valve comprises:
a first structural member coupled to the plurality of strut members;
a second structural member rotatable relative to the first structural member; and
a plurality of pliable valve members connecting the first structural member with the second structural member such that rotation of the second structural member relative to the first structural member urges the valve members between an open and a closed state.
7. The apparatus of claim 6 , wherein the rotation of the second structural member is responsive to the natural flow of a biological fluid.
8. The apparatus of claim 5 , wherein the prosthetic valve includes a plurality of pliable valve leaflets having commissures at the intersection of two strut members.
9. The apparatus of claim 8 , wherein the prosthetic valve includes a skirt material coupled to the strut members.
10. The apparatus of claim 1 , wherein the shaped structure is one of a cylindrical, a conical, or an hourglass shape.
11. A medical stent, comprising:
a plurality of elongated strut members, including inner strut members and outer strut members; and
articulations connecting the inner strut members and the outer strut members such that:
each inner strut member comprises articulations with three outer strut members;
none of the inner strut members comprises articulations with another inner strut member;
each outer strut member comprises articulations with three inner strut members; and
none of the outer strut members comprises articulations with another outer strut member, and wherein at each articulation, when the stent is at a maximally expanded orientation, the inner strut members are located closer to a central axis of the stent than the outer strut members.
12. The stent of claim 11 , wherein the articulation form scissor mechanisms with the inner strut members and the outer strut members.
13. The stent of claim 12 , wherein at least one articulation bisects an inner strut member and an outer strut member.
14. The stent of claim 12 , wherein the plurality of strut members are arranged as a series of linked scissor mechanisms.
15. The stent of claim 11 , wherein at least one articulation interconnects a first end of an inner strut member with a first end of an outer strut member.
16. The stent of claim 11 , further comprising an adjustment mechanism to exerting a force to urge the plurality of strut members about the articulations within a range of motion.
17. The stent of claim 11 , wherein the inner and outer strut members are non-linear.
18. The stent of claim 11 , further comprising a prosthetic valve coupled to the plurality of strut members.
19. The stent of claim 18 , wherein the prosthetic valve comprises:
a first structural member coupled to the plurality of strut members;
a second structural member rotatable relative to the first structural member; and
a plurality of pliable valve members connecting the first structural member with the second structural member such that rotation of the second structural member relative to the first structural member urges the valve members between an open and a closed state.
20. The stent of claim 19 , wherein the rotation of the second structural member is responsive to the natural flow of a biological fluid.
21. The stent of claim 18 , wherein the prosthetic valve includes a plurality of pliable valve leaflets having commissures at the intersection of two strut members.
22. The stent of claim 21 , wherein the prosthetic valve includes a skirt material coupled to the plurality of strut members.
23. The stent of claim 11 , wherein the plurality of strut members are arranged to form one of a cylindrical, a conical, or an hourglass shape.
24. The stent of claim 16 , wherein the adjustment mechanism is a screw mechanism.
25. The stent of claim 24 , wherein the screw mechanism is permanently attached to the plurality of strut members.
26. The stent of claim 11 , wherein the stent is coupled to a catheter.