Prosthetic mitral valve
A prosthetic mitral valve with a frame comprises at least one arm shaped to deploy among a region of chordae tendineae of the native mitral valve to deflect these chords in order to pull the native valve leaflets around the frame to avoid paravalvular leaks. The frame may be made from two parts that are connected by sutures. The prosthetic valve may be deployed by a catherer comprising a deployment clamp attached to the valve frame where the deployment clamp is actuable to induce rotation of the frame.
1. A method for use with a prosthetic valve that is configured to be deployed within a native atrio-ventricular valve of a heart of a mammalian subject, the native atrio-ventricular valve including a valve annulus, valve leaflets, chords, and papillary muscles, the method comprising:
placing a valve frame within the subject's heart, the valve frame including:
a valve frame body that is configured to support the prosthetic valve within the native atrio-ventricular valve, and that includes an atrial portion and a ventricular portion, and
at least one arm that is configured to extend from the ventricular portion of the valve frame;
subsequently, deploying the at least one arm among the chords of the native atrio-ventricular valve;
subsequently, rotating at least a portion of the valve frame, in a direction in which an interior of the arm faces, such as to cause the arm to (a) pull the native atrio-ventricular valve radially inward toward the valve frame, and (b) twist the native atrio-ventricular valve around the valve frame, by recruiting and deflecting at least a portion of the chords; and
subsequently, causing the frame body of the valve frame to radially expand, such as to trap the native valve leaflets in a partially closed and twisted configuration, to thereby at least partially seal a space between the native atrio-ventricular valve and the prosthetic valve.
2. The method according to claim 1 , wherein deploying the at least one arm among the chords of the native atrio-ventricular valve comprises deploying the at least one arm among the chords of the native atrio-ventricular valve such that the arm defines a curving inner surface that curves, as a radial distance of the arm from the ventricular portion increases, from a relatively more radial orientation of the curved surface to a relatively more circumferential orientation of the curved surface.
3. The method according to claim 1 , further comprising locking the deployed arm into position.
4. The method according to claim 1 , wherein deploying the at least one arm among the chords of the native atrio-ventricular valve comprises deploying the arm such that a chord receiving surface of the arm defines a slope that guides chords into a chord grasping region located between the arm and the ventricular portion, during the rotation of portion of the valve frame.
5. The method according to claim 1 , wherein causing the frame body of the valve frame to radially expand, such as to trap the native valve leaflets in the partially closed and twisted configuration comprises preventing blood flow between the native valve leaflets and the valve frame, at least in the direction passing from a ventricle to an atrium of the heart.
6. The method according to claim 1 , wherein deploying the at least one arm among the chords of the native atrio-ventricular valve comprises deploying the at least one arm among the chords of the native atrio-ventricular valve, even when the portion of the valve frame from which the at least one arm extends is in a radially-compressed state.
7. The method according to claim 1 , further comprising preventing the portion of the chords that are recruited by the arm from exiting the arm, using a protruding member shaped to protrude from the arm.
8. The method according to claim 1 , wherein the native atrio-ventricular valve includes a native mitral valve, and placing the valve frame within the patient's heart comprises placing within a left heart of the patient a valve frame that is configured to support the prosthetic valve within the native mitral valve.
9. The method according to claim 1 , wherein causing the frame body of the valve frame to radially expand, such as to trap the native valve leaflets in a partially closed and twisted configuration comprises using the at least one arm to trap the native valve leaflets in a partially closed and twisted configuration.
10. The method according to claim 1 , wherein causing the frame body of the valve frame to radially expand, such as to trap the native valve leaflets in a partially closed and twisted configuration comprises trapping the native valve leaflets between the atrial portion of the valve frame and the at least one arm.
11. The method according to claim 1 , wherein causing the frame body of the valve frame to radially expand, such as to trap the native valve leaflets in a partially closed and twisted configuration comprises causing a cylindrical portion of the valve frame that extends through an annular level of the native atrio-ventricular valve to radially expand toward the at least one arm, such as to trap the native valve leaflets between the cylindrical portion of the valve frame and the at least one arm.
12. The method according to claim 1 , wherein:
rotating at least the portion of the valve frame comprises twisting the leaflets of the native valve, such that the leaflets of the native valve are shaped into overlapping configurations with respect to each other, and
causing the frame body of the valve frame to radially expand, such as to trap the native valve leaflets in a partially closed and twisted configuration, to thereby at least partially seal the space between the native atrio-ventricular valve and the prosthetic valve comprises trapping the leaflets of the native valve in the overlapping configurations with respect to each other.
13. The method according to claim 12 , wherein twisting the leaflets of the native valve, such that the leaflets of the native valve are shaped into overlapping configurations with respect to each other comprises sealing commissures between the leaflets of the native atrio-ventricular valve by twisting the leaflets of the native valve into the overlapping configurations with respect to each other.
14. The method according to claim 1 , wherein deploying the at least one arm among the chords of the native atrio-ventricular valve comprises extending the arm radially to a distance sufficient to engage primary and secondary chords of the native atrio-ventricular valve.
15. The method according to claim 14 , wherein deploying the at least one arm among the chords of the native atrio-ventricular valve comprises extending the arm radially to a distance sufficient to further engage tertiary chords of the native atrio-ventricular valve.
16. Apparatus for use with a prosthetic valve that is configured to be deployed within a native atrio-ventricular valve of a heart of a mammalian subject, the native atrio-ventricular valve including a valve annulus, valve leaflets, chords, and papillary muscles, the apparatus comprising:
a valve frame configured to support the prosthetic valve within the native atrio-ventricular valve, the valve frame comprising:
a frame body comprising:
an atrial portion configured to be positioned such that, when the valve frame is deployed, at least a portion of the atrial portion is disposed on an atrial side of the native atrio-ventricular valve; and
a ventricular portion configured to be positioned such that, when the valve frame is deployed, at least a portion of the ventricular portion is disposed within a ventricle of the subject; and
at least one arm configured to extend from the ventricular portion of the frame body; and
a delivery device configured to:
deliver the valve frame to the native atrio-ventricular valve;
subsequently, deploy the at least one arm among the chords of the native atrio-ventricular valve;
subsequently, rotate at least a portion of the valve frame, in a direction in which an interior of the arm faces, such as to cause the arm to (a) pull the native atrio-ventricular valve radially inward toward the valve frame, and (b) twist the native atrio-ventricular valve around the valve frame, by recruiting and deflecting at least a portion of the chords; and
subsequently, cause the frame body of the valve frame to radially expand, such as to trap the native valve leaflets in a partially closed and twisted configuration between the arms and the frame body, to thereby at least partially seal a space between the native atrio-ventricular valve and the prosthetic valve.
17. The apparatus according to claim 16 , wherein:
the ventricular portion of the valve frame has radially-compressed and radially-expanded states; and
the at least one arm is configured to become deployed among the chords of native valve, even when the ventricular portion of the valve frame is in its radially-compressed state.
18. The apparatus according to claim 16 , wherein the valve frame comprises a protruding member shaped to protrude from the arm, and configured to bar the portion of the chords that are recruited by the arm from exiting the arm.
19. The apparatus according to claim 16 , wherein the native atrio-ventricular valve includes a mitral valve, and the valve frame is configured to support the prosthetic valve within the native mitral valve.
20. The apparatus according to claim 16 , wherein the valve frame is configured to trap the native valve leaflets in the partially closed and twisted configuration around the valve frame at least partially by the at least one arm trapping the chords in a twisted configuration around the valve frame.
21. The apparatus according to claim 16 , wherein the valve frame is configured to trap the native valve leaflets in the partially closed and twisted configuration around the valve frame by the atrial portion of the valve frame radially expanding against the at least one arm, such as to trap the native valve leaflets between the atrial portion of the valve frame and the at least one arm.
22. The apparatus according to claim 21 , wherein the atrial portion of the valve frame comprises a cylindrical portion that is configured to extend through an annular level of the native atrio-ventricular valve, and wherein the cylindrical portion of the atrial portion of the valve frame is configured to radially expand toward the at least one arm, such as to trap the native valve leaflets between the cylindrical portion of atrial portion of the valve frame and the at least one arm.
23. The apparatus according to claim 16 , wherein:
the arm is configured to twist the leaflets of the native valve, such that the leaflets of the native valve are shaped into overlapping configurations with respect to each other,
the valve frame is configured to seal the space between the native atrio-ventricular valve and the prosthetic valve by trapping the leaflets of the native valve in the overlapping configurations with respect to each other.
24. The apparatus according to claim 23 , wherein the arm is configured to seal commissures between the leaflets of the native atrio-ventricular valve by the twisting the leaflets of the native valve into the overlapping configurations with respect to each other.
25. The apparatus according to claim 16 , wherein the at least one arm is configured to deploy among the chords of the native atrio-ventricular valve to a distance sufficient to recruit and deflect at least primary and secondary chords of the native atrio-ventricular valve.
26. The apparatus according to claim 25 , wherein the at least one arm is configured to deploy among the chords of the native atrio-ventricular valve to a distance sufficient to further recruit and deflect tertiary chords of the native atrio-ventricular valve.