Implantable device and delivery system for reshaping a heart valve annulus
Systems, devices and methods related to various heart valve implants and for delivery of those implants are described. The implants may be used to re-size a native valve annulus or to replace a native heart valve. The implants include a re-sizable frame having angled struts. The implant is secured to tissue with anchors that can rotate without axial advancement to engage tissue while drawing the implant closer to the tissue. Collars are used to decrease the angle between struts of a frame to contract the implant. The implants can include a rotatable shaft, such as a threaded shaft, located internally to an axially translatable collar. Rotation of the shaft transmits force to the collar to cause the collar to translate axially, closing the angle of adjacent struts and decreasing the width of the implant and thus of the annulus. The implants can be delivered, secured and contracted via a catheter. The implants are repositionable and retrievable via catheter.
1. An implant for reshaping a mitral valve annulus, the implant comprising:
a tubular frame having a proximal end, a distal end and a central lumen extending therethrough;
the frame having a first pair of adjacent struts joined at a proximal apex;
a shaft carried by the proximal apex and having an outer thread, the shaft configured to rotate about a rotation axis;
a collar carried by the frame and at least partially surrounding the first pair of adjacent struts, the collar having an inner thread engaged with the outer thread of the shaft, wherein rotation of the shaft about the rotation axis causes the collar to advance along the first pair of adjacent struts to change an angle between the first pair of adjacent struts, and
an anchor carried by the frame and axially moveable between a first position and a second position, wherein in the first position the anchor advances axially relative to the frame in response to rotation of the anchor in a first direction, and in the second position the anchor is freely rotatable in the first direction without causing axial advance relative to the frame.
2. The implant of claim 1 , wherein rotation of the shaft about the rotation axis in a first direction causes the collar to advance along the first pair of adjacent struts toward the distal end to decrease the angle between the first pair of adjacent struts, thereby contracting the implant.
3. The implant of claim 2 , wherein rotation of the shaft about the rotation axis in a second direction that is opposite the first direction causes the collar to advance along the first pair of adjacent struts toward the proximal end to allow an increase in the angle between the first pair of adjacent struts, thereby allowing the implant to expand.
4. The implant of claim 1 , the frame further comprising a first support and a second support extending from the proximal apex toward the proximal end of the frame and at least partially defining a window configured to at least partially retain the shaft therein.
5. The implant of claim 1 , further comprising a coupling attached to a proximal end of the shaft, the coupling configured to be rotated by a driver to rotate the shaft.
6. The implant of claim 1 , wherein the tubular frame defines a central longitudinal axis, and the pair of adjacent struts are configured to incline radially outward relative to the central longitudinal axis.
7. The implant of claim 6 , wherein the adjacent pair of struts are configured to incline radially outward relative to the central longitudinal axis in response to decreasing the angle between the first pair of adjacent struts.
8. The implant of claim 1 , wherein a distal end of the shaft is positioned proximally to the proximal apex.
9. The implant of claim 8 , the frame comprising a second pair of adjacent struts joined at a distal apex, wherein the anchor is coupled with the distal apex.
10. The implant of claim 8 , wherein the anchor is a helical anchor.
11. The implant of claim 1 , the frame comprising a second pair of adjacent struts joined at a distal apex, wherein the distal apex includes an anchor housing configured to rotatably receive the anchor therethrough.
12. The implant of claim 11 , the housing having an opening extending axially therethrough, and the anchor is configured to engage tissue of the heart valve annulus in the second position by rotating within the housing while maintaining an axial position relative to the housing.
13. The implant of claim 12 , the opening having a proximal engagement structure and a distal chamber, wherein a maximum width of the distal chamber is greater than a minimum width of the proximal engagement structure.
14. The implant of claim 1 , further comprising:
a plurality of the first pair of adjacent struts, each pair joined at a respective proximal apex;
a plurality of the shafts each carried by the respective proximal apex;
a plurality of the collars each configured to engage a respective shaft; and
a plurality of the anchors each carried by the frame.
15. The implant of claim 14 , wherein there are eight pairs of adjacent struts, eight proximal apices, eight shafts, eight collars, and eight anchors.
16. An implant for reshaping a mitral valve annulus, the implant comprising:
a tubular frame having a first pair of adjacent struts joined at a proximal apex;
a rotatable shaft located at the proximal apex;
a collar at least partially surrounding the first pair of adjacent struts and the shaft, wherein rotation of the rotatable shaft causes the collar to advance along the first pair of adjacent struts to decrease an angle between the first pair of adjacent struts, thereby contracting the implant, and
an anchor carried by the frame and axially moveable between a first position and a second position, wherein in the first position the anchor advances axially relative to the frame in response to rotation of the anchor in a first direction, and in the second position the anchor is freely rotatable in the first direction without causing axial advance relative to the frame.
17. The implant of claim 16 , wherein a distal end of the shaft is positioned proximally to the proximal apex.
18. The implant of claim 16 , further comprising a window at the proximal apex that axially restrains the rotatable shaft.
19. The implant of claim 16 , further comprising:
the collar having an inner thread; and
the shaft having an outer thread configured to engage with the inner thread of the collar to advance the collar along the first pair of adjacent struts.
20. The implant of claim 16 , wherein the anchor is a helical anchor.