Adjustable endolumenal implant for reshaping the mitral valve annulus
Excessive dilation of the annulus of a mitral valve may lead to regurgitation of blood during ventricular contraction. This regurgitation may lead to a reduction in cardiac output. Disclosed are systems and methods relating to an implant configured for reshaping a mitral valve. The implant comprises a plurality of struts with anchors for tissue engagement. The implant is compressible to a first, reduced diameter for transluminal navigation and delivery to the left atrium of a heart. The implant may then expand to a second, enlarged diameter to embed its anchors to the tissue surrounding and/or including the mitral valve. The implant may then contract to a third, intermediate diameter, pulling the tissue radially inwardly, thereby reducing the mitral valve and lessening any of the associated symptoms including mitral regurgitation.
1. An implant for reshaping a heart valve annulus, comprising:
a tubular body having a proximal end, a distal end, a central lumen and a longitudinal axis extending therethrough, the tubular body dimensioned for positioning within an atrium and attachment to tissue surrounding the heart valve;
the tubular body comprising at least a first pair of adjacent struts joined at a proximally facing apex, and at least a second pair of adjacent struts joined at a distally facing apex;
a plurality of distally facing anchors on the distal end of the tubular body, the anchors configured to embed into tissue surrounding the heart valve;
a moveable restraint carried by the tubular body and configured to at least partially surround the first pair of adjacent struts, wherein the moveable restraint is axially movable relative to the proximally facing apex along the first pair of adjacent struts toward the distal end to decrease an angle between the first pair of adjacent struts; and
a rotatable threaded member secured with the proximally facing apex, the rotatable threaded member extending through the moveable restraint, wherein rotation of the rotatable threaded member causes the moveable restraint to move axially along the first pair of adjacent struts.
2. The implant of claim 1 , wherein the moveable restraint is moved along the pair of adjacent struts by sliding of the moveable restraint in response to rotation of the rotatable threaded member.
3. The implant of claim 1 , wherein the plurality of anchors are helical-shaped anchors rotatably carried by the implant body, and wherein rotation of the anchors causes the anchors to extend distally relative to the tubular body to embed into the tissue surrounding the heart valve.
4. The implant of claim 1 , further comprising a delivery mechanism comprising a rotational driver having a hook at a distal end and configured to transmit rotational motion to the rotatable threaded member to cause the moveable restraint to move axially along the first pair of adjacent struts.
5. The implant of claim 1 , wherein the moveable restraint comprises an internally threaded member.
6. The implant of claim 1 , wherein the rotatable threaded member is secured with the proximally facing apex via a retainer.
7. The implant of claim 1 , wherein the moveable restraint further comprises a locking ring.
8. The implant of claim 1 , wherein the moveable restraint comprises a nut.
9. The implant of claim 1 , wherein the moveable restraint comprises a clip.
10. The implant of claim 1 , wherein the moveable restraint is configured to reversibly adjust the tubular body radially within a working range.
11. The implant of claim 1 , wherein the plurality of anchors comprises eight anchors.
12. The implant of claim 1 , wherein the plurality of anchors each have a helical shape that engages the tissue by rotation of each anchor.
13. The implant of claim 1 , wherein the plurality of anchors are configured to embed into tissue surrounding the heart valve by extending the anchors distally relative to the implant body.
14. The implant of claim 1 , wherein the anchors are retractable.
15. The implant of claim 1 , further comprising:
a plurality of pairs of adjacent struts with each pair having an angle therebetween; and
a plurality of the moveable restraints, with each moveable restraint at least partially surrounding a respective pair of the plurality of pairs of adjacent struts, wherein each moveable restraint can be moved along the respective pair of adjacent struts to change the angle between the respective pair of adjacent struts, thereby causing the tubular body to change in diameter.
16. The implant of claim 1 , wherein the tubular body is further configured to operably couple to a replacement prosthetic heart valve.