Method for use at a heart valve
A method includes advancing apparatus including a core toward a patient's heart valve. The core tapers in a distal direction toward the smallest perimeter of the core. The apparatus includes a first ventricular arm, which is articulatable with respect to a first atrial arm at a first articulation site, and a second ventricular arm, which is articulatable with respect to a second atrial arm at a second articulation site. The articulation sites are adjacent to the smallest perimeter. The tapering of the core defines a minimum nonzero angle of the atrial arms with respect to a central longitudinal axis of the core. The method also includes clamping the first and second leaflets between the respective atrial arms and the respective ventricular arms. Other embodiments are also described.
1. A method, comprising:
advancing, toward a native heart valve of a heart of a patient, apparatus comprising:
(a) a core
(1) having a central longitudinal axis,
(2) having a first portion having a first perimeter in a first transverse plane to the central longitudinal axis,
(3) having a second portion having a second perimeter in a second transverse plane to the central longitudinal axis that is distal to the first transverse plane, the second perimeter being a smallest perimeter of the core, and
(4) tapering in a distal direction from the first portion to the second portion of the core;
(b) first and second ventricular arms; and
(c) first and second atrial arms, wherein:
the first ventricular arm is articulatable with respect to the first atrial arm at a first articulation site,
the second ventricular arm is articulatable with respect to the second atrial arm at a second articulation site,
the first and second articulation sites are adjacent to the smallest perimeter of the core, and
the tapering of the core defines a minimum nonzero angle of the first and second atrial arms with respect to the central longitudinal axis; and
subsequently to the advancing, clamping (i) a first native leaflet of the native heart valve between the first atrial arm and the first ventricular arm and (ii) a second native leaflet of the native heart valve between the second atrial arm and the second ventricular arm.
2. The method according to claim 1 , wherein:
the core is shaped so as to define a conduit therethrough, and
the method further comprises controlling the first and second ventricular arms using an elongate controller that is slidably disposed within the conduit.
3. The method according to claim 1 , wherein the step of clamping comprises forming the first and second native leaflets into a generally lemniscate arrangement.
4. The method according to claim 1 , wherein the tapering of the core is such that: (i) the first articulation site is disposed closer to the central longitudinal axis of the core than a terminal end of the first atrial arm is to the central longitudinal axis of the core, and (ii) the second articulation site is disposed closer to the central longitudinal axis of the core than a terminal end of the second atrial arm is to the central longitudinal axis of the core.
5. The method according to claim 1 , wherein the first atrial arm, the first ventricular arm, the second atrial arm, and the second ventricular arm are configured to allow the first and second native leaflets to function following the clamping, and wherein the step of clamping is performed in a manner that allows the first and second native leaflets to function following the clamping.
6. The method according to claim 1 , wherein the step of clamping does not eliminate native blood flow regulation functionality of the native heart valve.
7. The method according to claim 1 , further comprising, (i) subsequently to the advancing and (ii) prior to the step of clamping, moving the first and second ventricular arms with respect to the central longitudinal axis.
8. The method according to claim 7 , wherein moving the first and second ventricular arms comprises:
articulating the first ventricular arm with respect to the first atrial arm; and
articulating the second ventricular arm with respect to the second atrial arm.
9. The method according to claim 7 , wherein moving the first and second ventricular arms comprises moving the first and second ventricular arms while the first and second atrial arms are held in place.
10. The method according to claim 7 , wherein moving the first and second ventricular arms comprises operating the first and second ventricular arms simultaneously.
11. The method according to claim 7 , wherein moving the first and second ventricular arms comprises:
applying a distally-directed pulling force to the first ventricular arm from below the first ventricular arm; and
applying a distally-directed pulling force to the second ventricular arm from below the second ventricular arm.
12. The method according to claim 7 , further comprising, (i) subsequently to the moving of the first and second ventricular arms and (ii) prior to the step of clamping, positioning the core between first and second native leaflets of the native heart valve such that:
the first atrial arm faces an atrial surface of the first native leaflet,
the first ventricular arm faces a ventricular surface of the first native leaflet,
the second atrial arm faces an atrial surface of the second native leaflet, and
the second ventricular arm-faces a ventricular surface of the second native leaflet.
13. The method according to claim 12 , wherein positioning the core between the first and second native leaflets comprises positioning the core such that:
a proximal end portion of the core is disposed at an atrial side of the native heart valve, and
a distal end portion of the core is disposed at a ventricular side of the native heart valve.
14. The method according to claim 7 , wherein moving the first and second ventricular arms with respect to the central longitudinal axis comprises moving the first and second ventricular arms with respect to the central longitudinal axis while the first and second ventricular arms, the first and second atrial arms, and a distal end of the core are disposed in an atrium of the heart.
15. The method according to claim 14 , further comprising, subsequently to the moving:
advancing at least the first and second ventricular arms and the distal end of the core below respective ventricular surfaces of the first and second native leaflets; and
raising the first and second ventricular arms toward the central longitudinal axis.
16. The method according to claim 7 , wherein the apparatus comprises a ventricular section that is distal to the second portion of the core, and wherein moving the first and second ventricular arms comprises moving the first and second ventricular arms via the ventricular section.
17. The method according to claim 16 , wherein:
the core is shaped so as to define a conduit therethrough, and
the method further comprises controlling the first and second ventricular arms using an elongate controller that is slidably disposed within the conduit and passes through an opening in the ventricular section.
18. The method according to claim 16 , wherein the ventricular section is wider than the second portion of the core.