Cardiac leaflet coapters
A coaptation-assist device is provided for treating a native atrioventricular valve. The coaptation-assist device includes a ventricular anchor and a neo-leaflet. The ventricular anchor includes a subannular anchor and a ventricular wall anchor. The subannular anchor is configured to be anchored in position in a subannular space of a target native leaflet of the native atrioventricular valve. The ventricular wall anchor includes one or more anchor-loop wire loops, which are configured to be anchored in position against a ventricular wall outside the subannular space. The neo-leaflet is supported by the ventricular anchor and is configured to at least partially replace function of the target native leaflet by providing a surface of coaptation for one or more opposing native leaflets that oppose the target native leaflet, when the ventricular anchor is positioned in the ventricle. Other embodiments are also described.
1 . A coaptation-assist device for treating a native atrioventricular valve of a subject, the coaptation-assist device comprising:
a ventricular anchor, which is configured to be positioned in a ventricle, and which comprises:
a subannular anchor, which is configured to be anchored in position in a subannular space of a target native leaflet of the native atrioventricular valve; and
a ventricular wall anchor, which comprises one or more anchor-loop wire loops, which are configured to be anchored in position against a ventricular wall outside the subannular space; and
a neo-leaflet, which is supported by the ventricular anchor and is configured to at least partially replace function of the target native leaflet by providing a surface of coaptation for one or more opposing native leaflets that oppose the target native leaflet, when the ventricular anchor is positioned in the ventricle.
2 . The coaptation-assist device according to claim 1 , wherein the one or more anchor-loop wire loops comprise exactly one anchor-loop wire loop.
3 . The coaptation-assist device according to claim 2 , wherein the anchor-loop wire loop, when unconstrained, includes a distal-most portion that is curved away from a best-fit plane defined by lateral portions of the anchor-loop wire loop.
4 . The coaptation-assist device according to claim 2 , wherein the anchor-loop wire loop includes a distal-most portion that is configured to curve away from the ventricular wall when the anchor-loop wire loop is positioned in ventricle.
5 . The coaptation-assist device according to claim 1 , wherein the one or more anchor-loop wire loops comprise a plurality of linked anchor-loop wire loops.
6 . The coaptation-assist device according to claim 1 , wherein the one or more anchor-loop wire loops are shaped so as to define a plurality of loop-lobes.
7 . The coaptation-assist device according to claim 6 , wherein the plurality of loop-lobes comprises three loop-lobes.
8 . The coaptation-assist device according to claim 1 , wherein the ventricular anchor is configured to remain anchored in position by force applied by the one or more anchor-loop wire loops to surrounding anatomy.
9 . The coaptation-assist device according to claim 8 , wherein the ventricular anchor is configured to remain anchored in position by radially-outwardly-directed force applied by the one or more anchor-loop wire loops to the surrounding anatomy.
10 . The coaptation-assist device according to claim 1 , wherein the ventricular anchor is configured to be atraumatic so as not to penetrate tissue of surrounding anatomy.
11 . The coaptation-assist device according to claim 1 , wherein the coaptation-assist device does not comprise any elements that are configured to penetrate tissue.
12 . The coaptation-assist device according to claim 1 , wherein the one or more anchor-loop wire loops are configured to be anchored in position against the ventricular wall outside the subannular space, including a ventricular apical area, when the one or more anchor-loop wire loops are positioned in the ventricle.
13 . The coaptation-assist device according to claim 1 , wherein the one or more anchor-loop wire loops are configured to be anchored in position against the ventricular wall outside the subannular space, and one or more ventricular papillary muscles of a ventricular apical area, when the one or more anchor-loop wire loops are positioned in the ventricle.
14 . The coaptation-assist device according to claim 1 , wherein the neo-leaflet is configured such that the coaptation surface is generally static throughout a cardiac cycle of the subject upon implantation of the coaptation-assist device in a heart of the subject.
15 . The coaptation-assist device according to claim 1 , wherein the neo-leaflet is configured such that the coaptation surface moves toward and away from the one or more opposing native leaflets during a cardiac cycle of the subject upon implantation of the coaptation-assist device in a heart of the subject.
16 . The coaptation-assist device according to claim 1 , further comprising a native-leaflet grasper, which is configured to grasp atrial and ventricular surfaces of the target native leaflet, in order to support the neo-leaflet, and to orient the neo-leaflet with respect to the native atrioventricular valve.
17 . The coaptation-assist device according to claim 16 , comprising a wire that is shaped so as to at least partially define the ventricular anchor and the native-leaflet grasper.
18 . The coaptation-assist device according to claim 16 , wherein the native-leaflet grasper is shaped so as to define first and second portions that are configured to grasp the atrial and the ventricular surfaces of the target native leaflet by sandwiching at least a portion of the atrial and the ventricular surfaces of the target native leaflet between the first and the second portions of the native-leaflet grasper.
19 . The coaptation-assist device according to claim 18 , wherein the first and the second portions are configured to fold toward each other so as to grasp the atrial and the ventricular surfaces of the target native leaflet by sandwiching the at least a portion of the atrial and the ventricular surfaces of the target native leaflet between the first and the second portions of the native-leaflet grasper.
20 . The coaptation-assist device according to claim 19 ,
wherein the native-leaflet grasper is shaped so as to further define a third portion at a fold between the first and the second portions of the native-leaflet grasper, and
wherein the third portion of the native-leaflet grasper is configured to extend around the free edge of the target native leaflet when the first and the second portions of the native-leaflet grasper sandwich the at least a portion of the atrial and the ventricular surfaces of the target native leaflet.
21 . The coaptation-assist device according to claim 16 , wherein the native-leaflet grasper comprises one or more supra-annular supports, which are configured to press against an atrial surface of the target native leaflet when the one or more anchor-loop wire loops are positioned in the ventricle.
22 . The coaptation-assist device according to claim 1 , wherein the native atrioventricular valve is a tricuspid valve, and wherein the neo-leaflet is configured to at least partially replace function of the target native leaflet by providing a surface of coaptation for the one or more opposing native leaflets of the tricuspid valve, when the one or more anchor-loop wire loops are positioned in the ventricle.
23 . The coaptation-assist device according to claim 1 , wherein the native atrioventricular valve is a mitral valve, and wherein the neo-leaflet is configured to at least partially replace function of the target native leaflet by providing a surface of coaptation for the opposing native leaflet of the mitral valve, when the one or more anchor-loop wire loops are positioned in the ventricle.
24 . The coaptation-assist device according to claim 1 , wherein the coaptation-assist device is configured such that the coaptation surface of the neo-leaflet crosses from an atrial side to a ventricular side of a native valvular plane, when the one or more anchor-loop wire loops are positioned in the ventricle.
25 . The coaptation-assist device according to claim 1 , wherein the ventricular wall anchor further comprises an anchor-loop cover attached to the one or more anchor-loop wire loops.
26 . The coaptation-assist device according to claim 25 , wherein the anchor-loop cover comprises one or more thin sheets of material that extend across a space at least partially surrounded by the one or more anchor-loop wire loops.
27 . The coaptation-assist device according to claim 25 , wherein the anchor-loop cover comprises a coating on the one or more anchor-loop wire loops.
28 . The coaptation-assist device according to claim 1 , wherein the neo-leaflet comprises:
a neo-leaflet wire loop that defines at least a portion of a border of the neo-leaflet; and
a neo-leaflet cover, which is attached to the neo-leaflet wire loop and provides the surface of coaptation.
29 . The coaptation-assist device according to claim 28 , wherein the coaptation-assist device is configured such that when unconstrained, an angle is defined between (a) an anchor-loop best-fit plane defined by the one or more anchor-loop wire loops and (b) a neo-leaflet best-fit plane defined by the neo-leaflet wire loop, the angle between 60 and 100 degrees.
30 . The coaptation-assist device according to claim 1 , further comprising a pouch, which is configured to inflate by blood flow during a cardiac cycle of a heart of the subject, so as to push the coaptation-assist device against one or more of: a ventricular surface of the target native leaflet and an annulus of the native atrioventricular valve, thereby stabilizing the coaptation-assist device with respect to the native atrioventricular valve.
31 . The coaptation-assist device according to claim 30 ,
wherein the coaptation-assist device further comprises a native-leaflet grasper, which is configured to grasp atrial and ventricular surfaces of the target native leaflet, in order to support the neo-leaflet, and to orient the neo-leaflet with respect to the native atrioventricular valve, and
wherein the pouch is defined by the native-leaflet grasper.
32 . The coaptation-assist device according to claim 1 , wherein the neo-leaflet is configured such that, upon implantation of the coaptation-assist device in a heart of the subject, the coaptation surface is generally static throughout a cardiac cycle of the subject and the coaptation is provided by motion of the one or more opposing native leaflets against the generally static coaptation surface provided by the neo-leaflet.
33 . The coaptation-assist device according to claim 32 , further comprising a native-leaflet grasper, which is configured to grasp atrial and ventricular surfaces of the target native leaflet, in order to support the neo-leaflet, and to orient the neo-leaflet with respect to the native atrioventricular valve.
34 . A method for treating a native atrioventricular valve of a subject, the method comprising:
positioning a ventricular anchor of a coaptation-assist device in a ventricle, such that (a) a subannular anchor of the ventricular anchor is anchored in position in a subannular space of a target native leaflet of the native atrioventricular valve, and (b) one or more anchor-loop wire loops of a ventricular wall anchor of the ventricular anchor are anchored in position against a ventricular wall outside the subannular space; and
positioning a neo-leaflet of the coaptation-assist device such that the neo-leaflet is supported by the ventricular anchor and at least partially replaces function of the target native leaflet by providing a surface of coaptation for one or more opposing native leaflets that oppose the target native leaflet.
35 . The method according to claim 34 , wherein positioning the neo-leaflet comprises positioning the neo-leaflet such that, upon implantation of the coaptation-assist device in a heart of the subject, the coaptation surface is generally static throughout a cardiac cycle of the subject and the coaptation is provided by motion of the one or more opposing native leaflets against the generally static coaptation surface provided by the neo-leaflet.
36 . The method according to claim 35 , further comprising positioning a native-leaflet grasper of the coaptation-assist device to grasp atrial and ventricular surfaces of the target native leaflet, in order to support the neo-leaflet, and to orient the neo-leaflet with respect to the native atrioventricular valve.
37 . The method according to claim 34 , further comprising positioning a native-leaflet grasper of the coaptation-assist device to grasp atrial and ventricular surfaces of the target native leaflet, in order to support the neo-leaflet, and to orient the neo-leaflet with respect to the native atrioventricular valve.