IMPLANT FOR IMPROVING COAPTATION OF AN ATRIOVENTRICULAR VALVE

Abstract

The invention relates to an implant for improving coaptation of an atrioventricular valve in a heart, the atrioventricular valve having a native first leaflet, a native second leaflet and optionally an annulus adjacent a wall of an atrium of the heart, the implant comprising a support structure configured to be arranged on and fixed to the annulus or to at least one of the first and second native leaflets, the implant further comprising retention means fixed to the support structure so as to prevent prolapse of the at least one native leaflet, whereby the support structure comprises a resting element that is configured to rest against the wall of the atrium adjacent the valve.

Claims

1. An implant for improving coaptation of an atrioventricular valve in a heart, the atrioventricular valve having a native first leaflet, a native second leaflet and an annulus adjacent a wall of an atrium of the heart, the implant comprising a support structure configured to be arranged on and fixed to the annulus or to at least one of the first and second native leaflets, wherein the support structure comprises an upper support element to be arranged on a superior surface of the annulus or of the at least one of the first and second native leaflets and a lower support element to be arranged on an inferior surface of the annulus or of the at least one of the first and second native leaflets, the upper and the lower support elements each comprising connection means cooperating which each other for interconnecting the upper and the lower support elements while clamping a section of the annulus or of the at least one of the first and second native leaflets between the upper support element and the lower support element, the implant further comprising retention means fixed to the support structure so as to prevent prolapse of the at least one native leaflet, characterized in that the support structure comprises a resting element that is configured to rest against the wall of the atrium adjacent the atrioventricular valve, wherein the lower support element carries a holding element for holding the retention means.

2. The implant of claim 1, wherein at least one of the connection means comprises a penetrating section configured to penetrate the annulus or the at least one of the first and second native leaflets for being connected with the other connection means.

3. The implant of claim 1, wherein the resting element has a wing-like structure and is made of wire made of a shape-memory alloy.

4. The implant of claim 1, wherein the resting element is arranged in a plane that encloses an angle of 90-135° with a plane of the upper support element.

5. The implant of claim 1, wherein the support structure, the resting element and the retention means are deployable from a first position, in which the support structure and the retention means are folded for being arranged within a tubular housing of a delivery device, into a second position, in which the support structure, the resting element and the retention means are deployed.

6. The implant of claim 1, wherein the holding element comprises at least one holding arm, the region of which that is distal from the lower support element comprises a number of fixing means for fixing the retention means.

7. The implant of claim 1, wherein the retention means, on one end thereof, are connected to the upper support element or the resting element and, on the other end thereof, are connected to the holding element.

8. The implant of claim 1, wherein the retention means comprises one of: a flexible net, a plurality of flexible wires or yarns, a fabric, and a flat sheet.

9. The implant of claim 8, wherein the retention means comprises the plurality of flexible wires or yams, wherein the plurality of flexible wires or yarns comprises a first group of wires or yarns and a second group of wires or yarns, wherein the wires or yarns of the first group are crossing the wires or yarns of the second group.

10. The implant of claim 1, wherein the retention means are fixed on circular type fixing means arranged on the upper support element or the resting element having a wing-like structure and on the holding element, respectively.

11. The implant of claim 1, wherein the atrioventricular valve is a mitral valve and the at least one native leaflet is a posterior or an anterior leaflet of the mitral valve.

12. The implant of claim 6, wherein the support structure, the resting element, the holding element and the circular type fixing means are made of a shape-memory alloy.

13. The implant of claim 3, wherein the resting element having the wing-like structure comprises a plurality of wires extending over the length of the resting element and arranged in a spaced relationship to each other.

14. A system for deploying, comprising a deployment instrument with a tubular housing and the implant according to claim 1, wherein the tubular housing comprises two half-shells, a first half-shell housing the upper support element and the resting element, and a second half-shell housing the lower support element.

15. The system of claim 14, wherein the first and the second half-shells are arranged at a distal end of the deployment instrument.

16. The system of claim 14, wherein the first and the second half-shells are arranged to swing open in order to allow the implant to be deployed.

17. The system of claim 14, wherein the deployment instrument further comprises grasping means, which are arranged at a distal end of the deployment instrument and a proximal end of the first and second half-shells.

18. The system of claim 17, wherein the grasping means comprise an upper grasper and a lower grasper, which are arranged to move towards each other in order to grab the corresponding native first or second leaflet between them.

19. The system of claim 17, wherein the first and the second half-shells are arranged at a distal end of a first steerable part of the deployment instrument and the grasping means are arranged at a distal end of a second steerable part of the deployment instrument in order to be movable independently from each other.

Description

[0054] FIG. 1 is a schematic illustration of a human heart with the implant according to a first embodiment of the invention fixed to the mitral valve.

[0055] FIG. 2 is a perspective view of the implant according to a first embodiment of the invention.

[0056] FIG. 3 is a front view of the implant of FIG. 2.

[0057] FIG. 4 is a side view of the implant of FIG. 2.

[0058] FIG. 5 is a top view of the implant of FIG. 2.

[0059] FIG. 6 shows an upper part of the implant of FIG. 2 in a folded state.

[0060] FIG. 7 shows a lower part of the implant of FIG. 2 in a folded state.

[0061] FIG. 8 is a side view of the implant according to a second embodiment of the invention.

[0062] FIG. 9 is a perspective view of the implant of FIG. 8.

[0063] FIG. 10 shows the connection means optionally used in the implant of FIG. 2-10,

[0064] FIG. 11 shows the implant of FIG. 2 when fixed to a leaflet of a mitral valve.

[0065] FIG. 12a to 12f are schematic illustrations of the consecutive steps of deploying and fixing the implant to the mitral valve.

[0066] FIG. 13 shows step FIG. 12d with an alternative embodiment of the grasping elements.

[0067] FIG. 1 shows a schematic illustration of a human heart 1 comprising the right ventricle 2, the right atrium 3, the left ventricle 4 and the left atrium 5. The septum 6 divides the heart 1 in a right and a left section. The mitral valve 7 allows the blood to flow from the left atrium 5 into the left ventricle 4. The tricuspid valve 8 is located between the right atrium 3 and the right ventricle 2. The ascending aorta 9 originates at the orifice of the aortic valve 10. The mitral valve 7 comprises an anterior leaflet and a posterior leaflet that are anchored within the left ventricular cavity by chordae tendineae 11, which prevent the valve 7 from prolapsing into the left atrium 5. Furthermore, FIG. 1 shows the implant 12 according to a first embodiment of the invention as being fixed to the posterior leaflet of mitral valve 7, whereby the resting element 13 of the implant 12 rests against the wall of the left atrium 5. The retention means 14 of the implant 12 extend into the left ventricle 4 and cooperate with the posterior leaflet of mitral valve 7 thereby preventing its prolapse.

[0068] FIG. 2 is a perspective view of the implant according to a first embodiment of the invention. The implant for improving coaptation of the mitral valve is denoted by 12. The implant 12 comprises a support structure 15, retention means (not shown), which are fixed to the support structure 15, and a resting element 13. The support structure 15 comprises an upper support element 16 and a lower support element 17. The lower support element 17 carries a holding element 18 for holding the retention means 14 on one end thereof, whereby the retention means 14, on the other end thereof, are connected to the resting element 13. The retention means 14 comprise two groups of yarns crossing each other, which are fixed to circular type fixing means 19,20 arranged on the resting element 13 and on the holding element 18, respectively.

[0069] When being implanted to the posterior leaflet 33 of the mitral valve 7 of a human heart 1 the upper support element 16 is arranged on the superior surface of the posterior leaflet 33 of the mitral valve 7 and the lower support element 17 is arranged on the inferior surface of the posterior leaflet 33 of the mitral valve 7, whereby the upper support element 16 and the lower support element 17 cooperate which each other and thereby clamp the posterior leaflet in between and the implant 12 is hence fixed to the posterior leaflet 33. When being implanted the resting element 13 rests against the wall of the left atrium 5 adjacent the posterior leaflet 33 of the mitral valve 7 and the retention means 14, which are fixed to the support structure 15 of the implant 12, extend to the left ventricle 4 and thereby prevent prolapse of the posterior leaflet 33 of the mitral valve 7.

[0070] FIG. 3 is a front view of the implant 12 of FIG. 2, FIG. 4 is a side view and FIG. 5 is a top view of the implant 12 of

[0071] FIG. 2, whereby the same reference numerals as used in FIG. 2 are used for denoting the individual components of the implant 12.

[0072] For being delivered to the heart percutaneously, the implant 12 is folded in order to be housed in an elongate tubular housing of delivery device. FIG. 6 shows the upper part of the implant, comprising the upper support element 15 and the resting element, in its folded state. FIG. 7 shows the lower part of the implant 12, comprising lower support element 17 and the holding element 18, in its folded state.

[0073] FIG. 8 and 9 illustrate a second embodiment of the implant 12, which essentially corresponds to the first embodiment, but the holding element 18 of which is divided in two parts 180 and 181 that are detachable. The two parts 180 and 181 can be connected with each other with a screw connection consisting of a screw element 182 and a screw nut element 183. During production of the implant, the part 180 is detached from the part 181 so as to allow the implant 12 to be mounted on a stitching machine, that is used to manufacture the retention means 14 as an embroidery directly onto the implant 12.

[0074] Further, in FIG. 8 and 9 the implant 12 is shown with the lower support element 17 detached from the upper support element 16 so that the connection means for connecting the two support elements with each other are partly visible. In particular, the upper support element 16 comprises a penetration needle 160 that penetrates the leaflet 33 of the mitral valve when the upper support element 16 and the lower support element 17 are clamped together for being interconnected.

[0075] FIG. 10 shows the connection means of the support elements 16 and 17 in more detail. In particular, the upper support element 16, on its side facing the leaflet, carries a compressible layer or ring 161, which can be made of, e.g., PTFE. The lower support element 17, on its side facing the leaflet, carries a compressible layer or ring 171, which can be made of, e.g., PTFE. Thereby necrosis and/or apoptosis of the tissue between the upper and the lower support element may be avoided.

[0076] FIG. 11 schematically illustrates the implant 12 when being implanted. As can be seen, the retention means 14 is fixed to the holding arms 18 of the lower support element 17 and on the upper support element 16 and, between these fixing points, provides a structure that retains the leaflet 33 of the mitral valve 7 so as to prevent a prolapse. In order to prevent the implant 12 from excessively swinging into the left atrium 5 as a result of the dynamic pressure changes prevailing within the ventricle, the resting element 13 is arranged to rest against the wall 36 of the left atrium 5 adjacent the posterior leaflet 33.

[0077] FIG. 12a to 12f are schematic illustrations of the consecutive steps of deploying and fixing the implant to the heart tissue.

[0078] In order to advance the implant 12 to the mitral valve 7, the implant is in the first implanting step as depicted in FIG. 12a arranged in a tubular housing 21, which comprises a first half-shell 22 and a second half-shell 23, whereby the first half-shell 22 houses the upper part of the implant 12, i.e. the upper support element 16 and the resting element 13, and the second half-shell 23 houses the lower part of the implant 12, i.e. the lower support element 17 and the holding element 18 (cf. FIG. 12b). The first and the second half-shells 22,23 are arranged at the distal end of a first steerable part 36 of a deployment instrument 24, which is surrounded by a catheter-like tube 25 that may be advanced transapically, transaortically or transatrially into the heart. The deployment instrument 24 is further equipped with grasping means 26, which are arranged at the distal end of a second steerable part 37 of the deployment instrument 24. The grasping means 26 comprise an upper grasper 27 and a lower grasper 28, which are connected by a hinge.

[0079] As can be taken from FIG. 12b actuation means (not shown), which are arranged on the proximal end of the deployment instrument 24, induce the upper and the lower shells 22,23 of the tubular housing 21 to swing open and to unfold the upper and the lower graspers 27,28 of the grasping means 26 so as to unfold the retention means 14, which connect the upper part of the implant to the lower part of the implant.

[0080] In a first step the grasping means 26 are arranged such that the posterior leaflet 33 of mitral valve 7, on which the implant is to be fixed, is enclosed by the upper graspers 27 on its superior surface and the lower graspers 28 on its inferior surface, thereby holding the posterior leaflet 33 in place. To arrange the leaflet 33 in the desired position prior to fixing of the implant, i.e. between the upper shell 22 and the lower shell 23, the leaflet 33, which is grabbed between the upper and the lower graspers is pulled towards the distal end of the deployment instrument 24 according to arrow 29 by moving the second steerable part 37 of the deployment instrument 24 according to arrow 38. In a further step the first steerable part 36 of the deployment instrument 24 is actuated, whereby the first and the second half shell 22,23 move towards the posterior leaflet 33 according to arrows 30 and 31 and grab the same in between (cf. FIG. 12c and 12d). When the first and the second half shells 22,23 fully enclose the posterior leaflet 33 of the mitral valve 7, the upper and the lower support structure 16,17 of the implant 12 penetrates the leaflet 33, whereby the upper and the lower support element (not shown) of the implant interconnect.

[0081] In a next step (cf. FIG. 12e) the first and the second half shell 22,23 of the tubular housing 21 are opened thereby moving away from the posterior leaflet 33 and releasing the implant, which unfolds upon release and hence achieves its final state of implantation. After successful implantation of the implant 12 the deployment instrument 24 is retracted from the implantation site, whereby half shells 22 and 23 are shut and the deployment instrument 24 is moved backwards according to arrow 32 in order to be withdrawn from the heart (cf. FIG. 12f).

[0082] FIG. 13 shows an alternative embodiment of the delivery device, wherein the grasping means are replaced by clamping elements 34 and 35 that are pivotally connected to the upper and the lower shells 22,23 and are used to clamp the leaflet 33 between them to hold it in a suitable position, while the upper and the lower shells 22,23 are placed to position the lower and the upper supporting elements of the implant as close as possible to the annulus.