LEAFLET COAPTATION-ASSISTANCE DEVICES

Abstract

A leaflet coaptation-assist device (920, 1020, 1120) is provided for promoting valve coaptation of leaflets (22) of an atrioventricular valve, the leaflet coaptation-assist device (920, 1020, 1120) including a coaptation-assist surface (964, 1064, 1164) and one or more tissue anchors, which are configured to anchor the leaflet coaptation-assist device (920, 1020, 1120) in place within the heart, such that the coaptation-assist surface (964, 1064, 1164) is located at or below the leaflet hinge line and contacts an atrial side of the leaflets (22) during ventricular systole, thereby enhancing leaflet coaptation. In some configurations, the one or more tissue anchors include one or more ventricular loops (988, 1088, 1188), which are configured to couple the leaflet coaptation-assist device (920, 1020, 1120) to the ventricular wall by radial force and friction. Other embodiments are also described.

Claims

1. A leaflet coaptation-assist device for promoting valve coaptation of leaflets of an atrioventricular valve of a heart of a patient, the leaflet coaptation-assist device comprising: a coaptation-assist surface; and one or more tissue anchors, which are configured to anchor the leaflet coaptation-assist device in place within the heart of the patient, such that the coaptation-assist surface is located at or below the leaflet hinge line and contacts an atrial side of the leaflets during ventricular systole, thereby enhancing leaflet coaptation, the leaflets selected from the group consisting of: native leaflets and prosthetic leaflets, wherein the one or more tissue anchors comprise a non-tissue-piercing anchor, which comprises one or more ventricular loops, which are configured to couple the leaflet coaptation-assist device to a ventricular wall by radial force and friction.

2. The leaflet coaptation-assist device according to claim 1, wherein the one or more ventricular loops are configured to contact one or more of the atrioventricular leaflets at the commissural level and clip the one or more leaflets within the one or more ventricular loops to stabilize anchoring of the leaflet coaptation-assist device.

3. The leaflet coaptation-assist device according to claim 1, wherein the non-tissue-piercing anchor comprises a single ventricular loop.

4. The leaflet coaptation-assist device according to claim 1, wherein the non-tissue-piercing anchor comprises two or more ventricular loops.

5. The leaflet coaptation-assist device according to claim 4, wherein the two or more ventricular loops or cross one another.

6. The leaflet coaptation-assist device according to claim 4, wherein the two or more ventricular loops do not cross or touch one another.

7. The leaflet coaptation-assist device according to claim 1, wherein the one or more ventricular loops are configured to reach to a ventricular apical area.

8. The leaflet coaptation-assist device according to claim 1, wherein the atrioventricular valve is a mitral valve.

9. The leaflet coaptation-assist device according to claim 1, wherein the atrioventricular valve is a tricuspid valve.

10. The leaflet coaptation-assist device according to claim 1, wherein the one or more tissue anchors are configured to anchor the leaflet coaptation-assist device in place within the heart of the patient, such that the coaptation-assist surface is located at the leaflet hinge line and contacts the atrial side of the leaflets during ventricular systole, thereby blocking motion of the leaflets into an atrium and preventing leaflet prolapse.

11. The leaflet coaptation-assist device according to claim 1, wherein the one or more tissue anchors are configured to anchor the leaflet coaptation-assist device in place within the heart of the patient, such that the coaptation-assist surface is located below the leaflet hinge line such that the leaflets partially coapt with the coaptation-assist surface during ventricular systole.

12. The leaflet coaptation-assist device according to any one of claims 1-11, wherein the leaflet coaptation-assist device comprises a sheet having a lower surface that provides the coaptation-assist surface.

13. The leaflet coaptation-assist device according to claim 12, wherein the sheet has four sides.

14. The leaflet coaptation-assist device according to claim 13, wherein the sheet has a shape of a quadrilateral.

15. The leaflet coaptation-assist device according to claim 12, wherein the sheet is shaped so as to define three spokes extending radially outward from a central hub region.

16. The leaflet coaptation-assist device according to claim 15, wherein the three spokes are collectively shaped so as to define a deltoid curve.

17. The leaflet coaptation-assist device according to claim 13, wherein the sheet has two straight sides and two curved sides.

18. The leaflet coaptation-assist device according to claim 17, wherein the sheet has two straight shorter sides and two curved longer sides.

19. The leaflet coaptation-assist device according to claim 17, wherein the sheet has two straight longer sides and two curved shorter sides.

20. The leaflet coaptation-assist device according to claim 12, wherein the sheet has two longer sides and two shorter sides, and the shorter sides include respective stiffened portions.

21. The leaflet coaptation-assist device according to any one of claims 1-11, wherein the leaflet coaptation-assist device comprises a thick structure having a lower surface that provides the coaptation-assist surface.

22. The leaflet coaptation-assist device according to claim 21, wherein the thick structure comprises a solid foam.

23. The leaflet coaptation-assist device according to claim 21, wherein the thick structure comprises at least one balloon.

24. The leaflet coaptation-assist device according to claim 21, wherein the thick structure is curved on a ventricular side thereof.

25. The leaflet coaptation-assist device according to claim 24, wherein the thick structure is multi-curved on the ventricular side thereof.

26. The leaflet coaptation-assist device according to claim 21, wherein the thick structure is flat on an atrial side thereof.

27. The leaflet coaptation-assist device according to claim 21, wherein the thick structure has a greatest thickness in the atrial-ventricular direction of at least 3 mm.

28. The leaflet coaptation-assist device according to claim 27, wherein the thick structure has a greatest thickness in the atrial-ventricular direction of no more than 40 mm.

29. A leaflet coaptation-assist device for promoting valve coaptation of leaflets of a mitral valve of a heart of a patient, the leaflet coaptation-assist device comprising: a sheet having a lower surface that defines a coaptation-assist surface, and two longer sides and two shorter sides, the shorter sides including respective stiffened portions; and a plurality of tissue-piercing tissue anchors, which are configured to be coupled to a structure selected from the group consisting of: an annulus of the mitral valve and an annuloplasty ring implanted on the annulus of the mitral valve, so as to anchor the leaflet coaptation-assist device in place within the heart of the patient, such that the coaptation-assist surface is located at or below the leaflet hinge line and contacts an atrial side of the leaflets during systole, thereby enhancing leaflet coaptation, the leaflets selected from the group consisting of: native leaflets and prosthetic leaflets.

30. The leaflet coaptation-assist device according to claim 29, wherein the tissue anchors are configured to anchor the leaflet coaptation-assist device in place within the heart of the patient, such that the coaptation-assist surface is located at the leaflet hinge line and contacts the atrial side of the leaflets during systole, thereby blocking motion of the leaflets into an atrium and preventing leaflet prolapse.

31. The leaflet coaptation-assist device according to claim 29, wherein the tissue anchors are configured to anchor the leaflet coaptation-assist device in place within the heart of the patient, such that the coaptation-assist surface is located below the leaflet hinge line such that the leaflets partially coapt with the coaptation-assist surface during systole.

32. The leaflet coaptation-assist device according to claim 29, wherein each of the stiffened portions is formed by two layers of the sheet or by a folding of the sheet.

33. The leaflet coaptation-assist device according to claim 29, wherein the stiffened portions comprise respective stiffener elements.

34. The leaflet coaptation-assist device according to claim 29, wherein the tissue anchors are configured to anchor the leaflet coaptation-assist device to an annulus of the mitral valve.

35. The leaflet coaptation-assist device according to claim 29, wherein the tissue anchors are configured to anchor the leaflet coaptation-assist device to an annuloplasty ring implanted on an annulus of the mitral valve.

36. The leaflet coaptation-assist device according to claim 29, wherein the sheet has exactly four sides.

37. The leaflet coaptation-assist device according to claim 36, wherein the sheet has a shape of a quadrilateral.

38. The leaflet coaptation-assist device according to claim 36, wherein the sheet has two straight sides and two curved sides.

39. The leaflet coaptation-assist device according to claim 38, wherein the two shorter sides are straight and the two longer sides are curved.

40. The leaflet coaptation-assist device according to claim 38, wherein the two longer sides are straight and the shorter sides are curved.

41. The leaflet coaptation-assist device according to claim 29, wherein the tissue-piercing anchors comprise respective helical tissue-piercing coupling-elements.

42. The leaflet coaptation-assist device according to any one of claims 29-41, wherein the lower surface of the sheet has an elliptically convex curvature.

43. The leaflet coaptation-assist device according to claim 42, further comprising a curved stiffener that is coupled to the sheet and provides the elliptically convex curvature.

44. The leaflet coaptation-assist device according to any one of claims 29-41, wherein the lower surface of the sheet has a bi-lobal convex curvature having two rounded curvature shapes.

45. The leaflet coaptation-assist device according to claim 44, further comprising one or more curved stiffeners that are coupled to the sheet and provide the bi-lobal convex curvature.

46. The leaflet coaptation-assist device according to claim 43, wherein the curved stiffener comprises a material having a shape memory.

47. The leaflet coaptation-assist device according to any one of claims 29-41, wherein the tissue-piercing anchors are fixed to the coaptation-assist surface along the two shorter sides of the sheet.

48. The leaflet coaptation-assist device according to claim 47, wherein the tissue-piercing anchors are fixed to the coaptation-assist surface at or near respective centers of the two shorter sides of the sheet.

49. The leaflet coaptation-assist device according to claim 47, wherein the tissue-piercing anchors are fixed to the coaptation-assist surface at or near respective ends of the two shorter sides of the sheet.

50. The leaflet coaptation-assist device according to any one of claims 29-41, wherein the tissue-piercing anchors are separate and discrete from the leaflet coaptation-assist device, and are configured to be coupled to the leaflet coaptation-assist device and the structure in situ during an implantation procedure.

51. A leaflet coaptation-assist device for promoting valve coaptation of leaflets of a mitral valve of a heart of a patient, the leaflet coaptation-assist device comprising: a sheet having two longer sides and two shorter sides, and a lower surface that defines a coaptation-assist surface and has a convex curvature that is (a) elliptic or (b) bi-lobal having two rounded curvature shapes; and one or more tissue anchors, which are configured to anchor the leaflet coaptation-assist device in place within the heart of the patient, such that the coaptation-assist surface is located at or below the leaflet hinge line and contacts an atrial side of the leaflets during systole, thereby enhancing leaflet coaptation, the leaflets selected from the group consisting of: native leaflets and prosthetic leaflets.

52. The leaflet coaptation-assist device according to claim 51, wherein the one or more tissue anchors are configured to anchor the leaflet coaptation-assist device in place within the heart of the patient, such that the coaptation-assist surface is located at the leaflet hinge line and contacts the atrial side of the leaflets during systole, thereby blocking motion of the leaflets into an atrium and preventing leaflet prolapse.

53. The leaflet coaptation-assist device according to claim 51, wherein the one or more tissue anchors are configured to anchor the leaflet coaptation-assist device in place within the heart of the patient, such that the coaptation-assist surface is located below the leaflet hinge line such that the leaflets partially coapt with the coaptation-assist surface during systole.

54. The leaflet coaptation-assist device according to claim 51, wherein the convex curvature is elliptic.

55. The leaflet coaptation-assist device according to claim 51, wherein the convex curvature is bi-lobal.

56. The leaflet coaptation-assist device according to claim 51, wherein the one or more tissue anchors are configured to anchor the leaflet coaptation-assist device to an annulus of the mitral valve.

57. The leaflet coaptation-assist device according to claim 51, wherein the one or more tissue anchors are configured to anchor the leaflet coaptation-assist device to an annuloplasty ring implanted on an annulus of the mitral valve.

58. The leaflet coaptation-assist device according to any one of claims 51-57, further comprising a curved stiffener that is coupled to the sheet and provides the convex curvature.

59. The leaflet coaptation-assist device according to claim 58, wherein the curved stiffener comprises a material having a shape memory.

60. The leaflet coaptation-assist device according to any one of claims 51-57, wherein the shorter sides include respective stiffened portions.

61. The leaflet coaptation-assist device according to claim 60, wherein each of the stiffened portions is formed by two layers of the sheet or by a folding of the sheet.

62. The leaflet coaptation-assist device according to claim 60, wherein the stiffened portions comprise respective stiffener elements.

63. The leaflet coaptation-assist device according to any one of claims 51-57, wherein the sheet has exactly four sides.

64. The leaflet coaptation-assist device according to claim 63, wherein the sheet has a shape of a quadrilateral.

65. The leaflet coaptation-assist device according to claim 63, wherein the sheet has two straight sides and two curved sides.

66. The leaflet coaptation-assist device according to claim 65, wherein the two shorter sides are straight and the two longer sides are curved.

67. The leaflet coaptation-assist device according to claim 65, wherein the two longer sides are straight and the shorter sides are curved.

68. The leaflet coaptation-assist device according to any one of claims 51-57, wherein the one or more tissue anchors comprise a plurality of tissue-piercing anchors, which are configured to be coupled to a structure selected from the group consisting of: an annulus of the mitral valve and an annuloplasty ring implanted on the annulus of the mitral valve.

69. The leaflet coaptation-assist device according to claim 68, wherein the tissue-piercing anchors comprise respective helical tissue-piercing coupling-elements.

70. The leaflet coaptation-assist device according to claim 68, wherein the tissue-piercing anchors are fixed to the coaptation-assist surface along the two shorter sides of the sheet.

71. The leaflet coaptation-assist device according to claim 70, wherein the tissue-piercing anchors are fixed to the coaptation-assist surface at or near respective centers of the two shorter sides of the sheet.

72. The leaflet coaptation-assist device according to claim 70, wherein the tissue-piercing anchors are fixed to the coaptation-assist surface at or near respective ends of the two shorter sides of the sheet.

73. The leaflet coaptation-assist device according to claim 68, wherein the tissue-piercing anchors are separate and discrete from the leaflet coaptation-assist device, and are configured to be coupled to the leaflet coaptation-assist device and the structure in situ during an implantation procedure.

74. A leaflet coaptation-assist device for promoting valve coaptation of leaflets of an atrioventricular valve of a heart of a patient, the leaflet coaptation-assist device comprising: a thick structure having a lower surface that provides a coaptation-assist surface, wherein the thick structure is curved on a ventricular side thereof; and one or more tissue anchors, which are configured to anchor the leaflet coaptation-assist device in place within the heart of the patient, such that the coaptation-assist surface is located at or below the leaflet hinge line and contacts an atrial side of the leaflets during ventricular systole, thereby enhancing leaflet coaptation, the leaflets selected from the group consisting of: native leaflets and prosthetic leaflets.

75. The leaflet coaptation-assist device according to claim 74, wherein the thick structure comprises a solid foam.

76. The leaflet coaptation-assist device according to claim 74, wherein the thick structure comprises at least one balloon.

77. The leaflet coaptation-assist device according to claim 74, wherein the atrioventricular valve is a mitral valve.

78. The leaflet coaptation-assist device according to claim 74, wherein the atrioventricular valve is a tricuspid valve.

79. The leaflet coaptation-assist device according to claim 74, wherein the one or more tissue anchors are configured to anchor the leaflet coaptation-assist device in place within the heart of the patient, such that the coaptation-assist surface is located at the leaflet hinge line and contacts the atrial side of the leaflets during ventricular systole, thereby blocking motion of the leaflets into an atrium and preventing leaflet prolapse.

80. The leaflet coaptation-assist device according to claim 74, wherein the one or more tissue anchors are configured to anchor the leaflet coaptation-assist device in place within the heart of the patient, such that the coaptation-assist surface is located below the leaflet hinge line such that the leaflets partially coapt with the coaptation-assist surface during ventricular systole.

81. The leaflet coaptation-assist device according to claim 74, wherein the one or more tissue anchors are configured to anchor the leaflet coaptation-assist device to an annulus of the atrioventricular valve.

82. The leaflet coaptation-assist device according to claim 74, wherein the one or more tissue anchors are configured to anchor the leaflet coaptation-assist device to an annuloplasty ring implanted on an annulus of the atrioventricular valve.

83. The leaflet coaptation-assist device according to claim 74, wherein the one or more tissue anchors comprise a plurality of tissue-piercing anchors, which are configured to be coupled to a structure selected from the group consisting of: an annulus of the atrioventricular valve and an annuloplasty ring implanted on the annulus of the atrioventricular valve.

84. The leaflet coaptation-assist device according to claim 83, wherein the tissue-piercing anchors comprise respective helical tissue-piercing coupling-elements.

85. The leaflet coaptation-assist device according to claim 83, wherein the coaptation-assist surface has four sides, and wherein the tissue-piercing anchors are fixed to the coaptation-assist surface along two shorter sides of the coaptation-assist surface.

86. The leaflet coaptation-assist device according to claim 85, wherein the tissue-piercing anchors are fixed to the coaptation-assist surface at or near respective centers of the two shorter sides of the coaptation-assist surface.

87. The leaflet coaptation-assist device according to claim 85, wherein the tissue-piercing anchors are fixed to the coaptation-assist surface at or near respective ends of the two shorter sides of the coaptation-assist surface.

88. The leaflet coaptation-assist device according to claim 83, wherein the tissue-piercing anchors are separate and discrete from the leaflet coaptation-assist device, and are configured to be coupled to the leaflet coaptation-assist device and the structure in situ during an implantation procedure.

89. The leaflet coaptation-assist device according to claim 74, wherein the one or more tissue anchors comprise a non-tissue-piercing anchor, which is configured to couple the leaflet coaptation-assist device to a native cardiac structure.

90. The leaflet coaptation-assist device according to claim 89, wherein the non-tissue-piercing anchor comprises a stent, which is configured to couple the leaflet coaptation-assist device to atrial tissue by radial force and friction.

91. The leaflet coaptation-assist device according to claim 89, wherein the non-tissue-piercing anchor comprises one or more ventricular loops, which are configured to couple the leaflet coaptation-assist device to a ventricular wall by radial force and friction.

92. The leaflet coaptation-assist device according to claim 91, wherein the one or more ventricular loops are configured to contact one or more of the atrioventricular leaflets at the commissural level and clip the one or more leaflets within the one or more ventricular loops to stabilize anchoring of the leaflet coaptation-assist device.

93. The leaflet coaptation-assist device according to claim 74, wherein the thick structure has a greatest thickness in the atrial-ventricular direction of at least 3 mm.

94. The leaflet coaptation-assist device according to claim 93, wherein the thick structure has a greatest thickness in the atrial-ventricular direction of no more than 40 mm.

95. The leaflet coaptation-assist device according to any one of claims 74-94, wherein the thick structure is multi-curved on the ventricular side thereof.

96. The leaflet coaptation-assist device according to any one of claims 74-94, wherein the thick structure is flat on an atrial side thereof.

97. A leaflet coaptation-assist device for promoting valve coaptation of leaflets of a tricuspid valve of a heart of a patient, the leaflet coaptation-assist device comprising: a sheet, which is shaped so as to define three spokes extending radially outward from a central hub region, and which as a lower surface that defines a coaptation-assist surface; and one or more tissue anchors, which are configured to anchor the leaflet coaptation-assist device in place within the heart of the patient, such that the coaptation-assist surface is located at or below the leaflet hinge line and contacts an atrial side of the leaflets during ventricular systole, thereby enhancing leaflet coaptation, the leaflets selected from the group consisting of: native leaflets and prosthetic leaflets.

98. The leaflet coaptation-assist device according to claim 97, wherein the three spokes are collectively shaped so as to define a deltoid curve.

99. The leaflet coaptation-assist device according to claim 97, wherein radially-outward ends of the spokes include respective stiffened portions.

100. The leaflet coaptation-assist device according to any one of claims 97-99, wherein the one or more tissue anchors comprise a non-tissue-piercing anchor, which comprises one or more ventricular loops, which extend in a ventricular direction from the sheet to stabilize the leaflet coaptation-assist device within a ventricular chamber.

101. The leaflet coaptation-assist device according to any one of claims 97-99, wherein the one or more tissue anchors comprise a plurality of tissue-piercing anchors.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0045] FIGS. 1A-B are schematic illustrations of a leaflet coaptation-assist device, in accordance with an application of the present invention;

[0046] FIGS. 2A-C are schematic illustrations of another leaflet coaptation-assist device, in accordance with an application of the present invention;

[0047] FIG. 2D is a schematic illustration of the leaflet coaptation-assist device of FIGS. 2A-C implanted in a mitral valve, in accordance with an application of the present invention;

[0048] FIGS. 3A-D are schematic illustrations of still another leaflet coaptation-assist device, in accordance with an application of the present invention;

[0049] FIG. 3E is a schematic illustration of the leaflet coaptation-assist device of FIGS. 3A-D implanted in a mitral valve, in accordance with an application of the present invention;

[0050] FIG. 4 is a schematic illustration of yet another leaflet coaptation-assist device implanted in the mitral valve, in accordance with an application of the present invention;

[0051] FIGS. 5A-D are schematic illustrations of another leaflet coaptation-assist device, in accordance with an application of the present invention;

[0052] FIGS. 6A-B are schematic illustrations of still another leaflet coaptation-assist device, in accordance with an application of the present invention;

[0053] FIG. 6C is a schematic illustration of the leaflet coaptation-assist device of FIGS. 6A-B implanted in a mitral valve, in accordance with an application of the present invention;

[0054] FIG. 6D is a schematic illustration of a tissue anchor implanted in tissue of the native annulus, in accordance with an application of the present invention;

[0055] FIGS. 7A-C are schematic illustrations of still another leaflet coaptation-assist device, in accordance with an application of the present invention;

[0056] FIGS. 8 and 9 are schematic illustrations of additional leaflet coaptation-assist devices, in accordance with respective applications of the present invention;

[0057] FIGS. 10A-D are schematic illustrations of another leaflet coaptation-assist device, in accordance with an application of the present invention;

[0058] FIGS. 10E-G are schematic illustrations of the leaflet coaptation-assist device of FIGS. 10A-D implanted in a mitral valve, in accordance with an application of the present invention;

[0059] FIGS. 11A-E are schematic illustrations of still another leaflet coaptation-assist device, in accordance with an application of the present invention;

[0060] FIGS. 12A-D are schematic illustrations of yet another leaflet coaptation-assist device, in accordance with an application of the present invention;

[0061] FIGS. 13A-D are schematic illustrations of another leaflet coaptation-assist device, in accordance with an application of the present invention;

[0062] FIGS. 14A-F are schematic illustrations of still another leaflet coaptation-assist device, in accordance with an application of the present invention;

[0063] FIG. 14G is a schematic illustration of the leaflet coaptation-assist device of FIGS. 14A-F implanted in the mitral valve, in accordance with an application of the present invention;

[0064] FIGS. 15A-B are schematic illustrations of yet another leaflet coaptation-assist device, in accordance with an application of the present invention; and

[0065] FIG. 15C is a schematic illustration of the leaflet coaptation-assist device of FIGS. 15A-B implanted in a tricuspid valve, in accordance with an application of the present invention.

DETAILED DESCRIPTION OF APPLICATIONS

[0066] Embodiments of the present invention provide leaflet coaptation-assist devices and methods for promoting valve coaptation of leaflets of an atrioventricular valve of a heart of a patient. In general, these techniques enhance coaptation by placing a patch or barrier at or near the flexural level (i.e., the leaflet hinge line, demarcated by an annulus 10) of the atrioventricular valve. Typically, these techniques limit the natural leaflet movement to level at or less than the flexural level. These techniques may be used to improve coaptation of native leaflets or prosthetic leaflets of a prosthetic valve and/or reduce or prevent valve prolapse, thereby minimizing leakage.

[0067] For some applications, the leaflet coaptation-assist devices described herein are delivered in a percutaneous transcatheter delivery procedure, and are thus capable of assuming both compressed delivery and expanded operational configurations. Typically, for these applications, the leaflet coaptation-assist devices are configured to be self-expanding upon release from the delivery system at the target location. Alternatively, the leaflet coaptation-assist devices are delivered transapically, or during an open surgical procedure.

[0068] FIGS. 1A-B are schematic illustrations of a leaflet coaptation-assist device 20, in accordance with an application of the present invention. Leaflet coaptation-assist device 20 is configured to enhance leaflet coaptation of leaflets 22 (either native leaflets or prosthetic leaflets) of a mitral valve 24. Leaflets 22 include a posterior mitral leaflet 22A and an anterior mitral leaflet 22B. Mitral valve 24 is shown during diastole and systole in FIGS. 1A and 1B, respectively. In FIG. 1B, posterior mitral leaflet 22A is shown as prolapsing above anterior mitral leaflet 22B. Of course, as used herein, “systole” means “ventricular systole,” and “diastole” means “ventricular diastole,” in accordance with standard usage in the art and as evident from the drawings.

[0069] Leaflet coaptation-assist device 20 comprises: [0070] a sheet 30 (i.e., a broad, thin, generally planar piece of material) having two longer sides 32 and two shorter sides 34, and a lower surface that defines a coaptation-assist surface; and [0071] one or more tissue anchors 40, which are configured to anchor leaflet coaptation-assist device 20 in place within the heart, such that the two shorter sides 34 are disposed along two respective commissural areas 42A and 42B of annulus 10 of mitral valve 24 near respective commissures 44A and 44B of mitral valve 24, and the coaptation-assist surface is located at or below the leaflet hinge line and contacts respective atrial sides 46 of leaflets 22 during systole, such that both of leaflets 22 coapt with the coaptation-assist surface during systole.

[0072] For some applications, leaflet coaptation-assist device 20 is implanted such that, during systole, respective free edges 48 of leaflets 22 coapt with the coaptation-assist surface along entire lengths of free edges 48, such that the coaptation-assist surface entirely covers an orifice 50 of mitral valve 24.

[0073] Alternatively, for some applications, the leaflet coaptation-assist device is implanted such that, during systole, (a) a first free edge 48 of a first one of leaflets 22 coapts with the coaptation-assist surface along a majority of a first length of the first free edge 48, and (b) a second free edge 48 of a second one of leaflets 22 coapts with the coaptation-assist surface along a majority of a second length of the second free edge 48. Optionally, the leaflet coaptation-assist device is implanted such that, during systole, the first free edge 48 of the first one of leaflets 22 coapts with the coaptation-assist surface along an entirety of the first length of the first free edge 48 (and the second free edge 48 of the second one of leaflets 22 coapts with the coaptation-assist surface along a majority, but not an entirety, of the second length of the second free edge 48).

[0074] Leaflet coaptation-assist device 20 thus limits the movement of the native, and or other mitral assist device, to the level of placement of the device.

[0075] For example, for treating degenerative mitral valve regurgitation, leaflet coaptation-assist device 20 may block motion of leaflets 22 into the atrium and prevent leaflet prolapse; for such treatment, leaflet coaptation-assist device 20 is typically, although not necessarily, implanted at the leaflet hinge line. In addition, for example, for treating functional mitral valve regurgitation, leaflet coaptation-assist device 20 may provide a surface against which leaflets 22 partially coapt during systole so as to fill the area of non-coaptation between leaflets 22; for such treatment, leaflet coaptation-assist device 20 is typically, although not necessarily, implanted such that the coaptation surface thereof is below the leaflet hinge line, e.g., at least 2 mm, no more than 15 mm, and/or between 2 and 15 mm below the leaflet hinge line.

[0076] Optionally, sheet 30 has a thickness of less than 0.5 mm.

[0077] For some applications, sheet 30 is less flexible in two regions near the respective two shorter sides 34 than in a central region of the sheet.

[0078] In some applications of the present invention, a method is provided for promoting valve coaptation in a patient. The method comprises identifying incomplete coaptation of leaflets 22 of mitral valve 24, the leaflets 22 selected from the group consisting of: native leaflets and prosthetic leaflets. Leaflet coaptation-assist device 20 is implanted, the device including sheet 30 having the two longer sides 32 and the two shorter sides 34, such that the two shorter sides 34 are disposed along two respective commissural areas 42A and 42B of annulus 10 of mitral valve 24 near respective commissures 44A and 44B of mitral valve 24, and the coaptation-assist surface defined by the lower surface of sheet 30 is located at or below the leaflet hinge line and contacts respective atrial sides of leaflets 22 during systole, such that both of leaflets 22 coapt with the coaptation-assist surface during systole.

[0079] For some applications, sheet 30 has exactly four sides (as shown), e.g., has the shape of a quadrilateral (as shown), e.g., is rectangular (as shown) (rectangular sheet 30 does not appear entirely rectangle in FIGS. 1A-B because it has been deformed by attachment to the annulus). For some of these applications, tissue anchors 40 may be located at the four corners of sheet 30, such as shown. This enhances coaptation of the valve by forcing better coaptation and covering areas of poor coaptation.

[0080] Tissue anchors 40 may comprise screws, stents, stapes, sutures, loops, or any other suitable tissue anchors known in the art.

[0081] FIGS. 2-15C are schematic illustrations of leaflet coaptation-assist devices, in accordance with respective applications of the present in invention. Each of these leaflet coaptation-assist devices may be similar in some respects to leaflet coaptation-assist device 20, described hereinabove with reference to FIGS. 1A-B, and may implement any of the features thereof, mutatis mutandis. The features of the leaflet coaptation-assist devices illustrated in FIGS. 1A-B and 2-15C may be implemented in any combination. Although the leaflet coaptation-assist devices of FIGS. 1A-B and 2-14G are described and/or shown as treating the mitral valve, the leaflet coaptation-assist devices may also treat the tricuspid valve, the other atrioventricular valve, mutatis mutandis, as described hereinbelow, for example, with reference to FIGS. 15A-C.

[0082] Each of the leaflet coaptation-assist devices comprises a coaptation-assist surface, which may, for example, be provided by a lower surface of a sheet, such as shown in FIGS. 2A-D, 3A-E, 4, 5A-D, 10A-G, 11A-E, 12A-D, 13A-D, 14A-G, and 15A-C, or a lower surface of a curved thick structure, such as a balloon or solid foam, such as shown in FIGS. 6A-D, 7A-C, 8, and 9. For some applications, the sheets comprise one or more of the following materials: biological tissue (e.g., pericardium), silicone, PEEK, silk, perylene, polyethylene, polyester, PVDF membrane, foam (e.g., polyurethane foam), a plastic material, rubber, latex, ePTFE, polyethylene, PET, nylon, or a metal (e.g., braided wires or tiny plate of nitinol) covered or coated. For some applications, the thick structure is covered with one or more of the above-listed materials.

[0083] Typically, the material of sheet 30 is flexible (rather than rigid), and optionally is floppy, i.e., generally does not retain its shape when not constrained to do so. However, the stiffened portions described below (e.g., stiffened portions 160), if formed from the sheet, are typically rigid or bendable.

[0084] For some applications, sheets of the leaflet coaptation-assist devices of FIGS. 1A-B and 2-14G have four sides. For example, the sheets of the leaflet coaptation-assist devices may: [0085] have the shape of a quadrilateral (four straight sides), e.g., a rectangle, such as shown in FIGS. 1A-B, 2A-D, 10A-G, 11A-E, 12A-D, 13A-D, and 14A-G; [0086] have two straight sides and two curved sides (e.g., (a) two straight shorter sides and two curved longer sides, such as shown in FIGS. 3A-E and 5A-D, or (b) two straight longer sides and two curved shorter sides, such as shown in FIG. 4; [0087] have four curved sides (configuration not shown); or [0088] be shaped so as to define three spokes 1433 extending radially outward from a central hub region 1435, which may collectively have a deltoid curve shape (e.g., three straight short sides and three curved longer sides, such as shown in FIGS. 15A-C).

[0089] For other applications, the leaflet coaptation-assist devices have three sides or five or more sides (e.g., five to eight sides) (configurations not shown).

[0090] For some applications, the leaflet coaptation-assist devices of FIGS. 1A-B and 2-9 comprise a plurality of tissue-piercing anchors, which are optionally fixed to the sheet or thick structure, typically along shorter sides of the sheet or thick structure. The tissue-piercing anchors are configured to be coupled to the annulus of native valve or an annuloplasty ring (such as a rigid or semi-rigid ring, or a band) implanted around all or a portion of the native annulus, preferably at the leaflets commissural level. For example, the tissue-piercing anchors may comprise respective helical tissue-piercing coupling-elements, as shown.

[0091] For example, the tissue-piercing anchors may be fixed to the sheet: [0092] at or near the centers of the shorter sides of the sheet or leaflet coaptation-assist device, such as shown in FIGS. 2A-D, 6A-D, and 7A-C; [0093] at or near the ends of the shorter sides of the sheet, such as shown in FIGS. 1A-B, 3A-E, and 4, in which case the leaflet coaptation-assist device comprises at least four tissue-piercing anchors; and [0094] both at or near the centers of the shorter sides and at or near the ends of the shorter sides, such as shown in FIGS. 5A-D, in which case the leaflet coaptation-assist device comprises at least six tissue-piercing anchors.

[0095] Alternatively, in any of the configurations described hereinabove and hereinbelow, the tissue-piercing anchors are not fixed to the leaflet coaptation-assist device, but rather are separate and discrete from the leaflet coaptation-assist device, and are coupled to the sheet in situ during an implantation procedure.

[0096] Further alternatively, in some configurations, the leaflet coaptation-assist devices comprise a non-tissue-piercing anchor, such as described hereinbelow with reference to FIGS. 10A-G, 11A-E, 12A-D, 13A-D, 14A-G, and 15A-C.

[0097] FIGS. 2A-C are schematic illustrations of a leaflet coaptation-assist device 120, in accordance with an application of the present invention, and FIG. 2D is a schematic illustration of leaflet coaptation-assist device 120 implanted in mitral valve 24, in accordance with an application of the present invention. In this configuration, leaflet coaptation-assist device 120 comprises a sheet 130, a lower surface 162 of which provides a coaptation-assist surface 164.

[0098] For some applications, as illustrated, the two shorter sides 34 of sheet 130 include respective stiffened portions 160 (which are stiffer than the remainder of sheet 130), which may be formed by two layers of sheet 130, or a folding of sheet 130, and/or comprise stiffener elements, which stabilize the leaflet coaptation-assist device against the annular tissue or annuloplasty ring. The stiffener elements may comprise of a polymer, a superelastic material, or a combination of such materials. Optionally, the stiffener elements comprise stitching.

[0099] Stiffened portions 160 help maintain the shape of sheet 130 (e.g., the rectangular shape, as shown), and allow the optional use of only a single tissue anchor 40 at each shorter side 34 rather than two or more anchors 40 to maintain the shape of sheet 130.

[0100] For some applications, the two longer sides 32 of sheet 130 have a length of at least 2 cm, no more than 6 cm, and/or between 2 and 6 cm, and/or the two shorter sides 34 of sheet 130 have a length of at least 0.5 cm, no more than 3 cm, and/or between 0.5 and 3 cm. Alternatively or additionally, for some applications, a ratio of the length of the longer sides 32 to the length of the shorter sides 34 is at least 2:1, no more than 5:1, and/or between 2:1 and 5:1.

[0101] For some applications, tissue anchors 40 are coupled to sheet 130 via the respective stiffened portions 160, such as shown.

[0102] FIGS. 3A-D are schematic illustrations of a leaflet coaptation-assist device 220, in accordance with an application of the present invention, and FIG. 3E is a schematic illustration of leaflet coaptation-assist device 120 implanted in mitral valve 24, in accordance with an application of the present invention. In this configuration, leaflet coaptation-assist device 220 comprises a sheet 230 having a ventricular (lower) surface 262 that provides a coaptation-assist surface 264. Sheet 230 is elliptically curved with a curvature shape toward the ventricular (lower) surface; in other words, lower surface 262 of sheet 230 has an elliptically convex curvature. The curvature provides multiple planes of coaptation for leaflets 22, rather than a single plane along the implantation plane.

[0103] For example, the curved shape (elliptically convex curvature) may be provided by a curved stiffener 270 coupled to (e.g., embedded within) sheet 230. For example, curved stiffener 270 may comprise a material having a shape memory, such as a metal (e.g., Nitinol) or a polymer.

[0104] For some applications, leaflet coaptation-assist device 220 comprises two tissue-piercing anchors 40 at or near the ends of each shorter side 34 of sheet 230; alternatively, leaflet coaptation-assist device 220 comprises fewer or more tissue-piercing anchors 40, or no tissue-piercing anchors (for example, as described hereinbelow with reference to FIGS. 10A-G, 11A-E, 12A-D, 13A-D, 14A-G, and 15A-C, mutatis mutandis). Sheet 230 may have two straight shorter sides 34 and two curved longer sides 232 (such as shown); the excess material of the curvatures may help fully cover orifice 50 of mitral valve 24. Alternatively, sheet 230 may be rectangular (configuration not shown, but similar to the configuration shown in FIGS. 2A-D).

[0105] FIG. 4 is a schematic illustration of a leaflet coaptation-assist device 320 implanted in mitral valve 24, in accordance with an application of the present invention. In this configuration, leaflet coaptation-assist device 320 comprises a sheet 330 having curved shorter sides 334 and straight longer sides 332, and curved stiffened portions 360 corresponding the curvature of curved shorter sides 334. Stiffened portions 360 may implement any of the features of stiffened portions 160, described hereinabove with reference to FIGS. 2A-D, mutatis mutandis. Alternatively, longer sides 332 are also curved, like longer sides 232 described hereinabove with reference to FIGS. 3A-E.

[0106] Alternatively, in another configuration, shorter sides 334 are straight when in a relaxed, resting configuration, and are bendable by forces applied during implantation, in order to assume the curved configurations shown in FIG. 4.

[0107] Optionally, sheet 330 is elliptically curved, similar to elliptic curved sheet 230, described hereinabove with reference to FIGS. 3A-E.

[0108] FIGS. 5A-D are schematic illustrations of a leaflet coaptation-assist device 420, in accordance with an application of the present invention. In this configuration, leaflet coaptation-assist device 420 comprises a concave multi-curved sheet 430, with two rounded convex curvature shapes lateral to sheet 430, near shorter sides 34 of sheet 430. A ventricular (lower) surface 462 of sheet 430 provides a coaptation-assist surface 464. In other words, lower surface 462 of sheet 430 has a bi-lobal convex curvature having two rounded curvature shapes. The curvature provides multiple planes of coaptation for leaflets 22, rather than a single plane along the implantation plane.

[0109] The bi-lobal shape may be provided by one or more (e.g., one, two, or three) curved stiffeners 480A, 480B, and/or 482 coupled to (e.g., embedded within) sheet 430. For example, the curved stiffeners may comprise a material having a shape memory, such as a metal (e.g., Nitinol) or a polymer. For example, the one or more curved stiffeners may include two edge curved stiffeners 480A and 480B that run along longer sides 432 of sheet 430, and/or a center curved stiffener 482 that runs along a longer centerline of sheet 430, as shown.

[0110] For some applications, leaflet coaptation-assist device 420 comprises three tissue-piercing anchors 40, of which two are at or near the ends of each shorter side 34 of sheet 430 and one is at or near the center of each shorter side 34 of sheet 430; alternatively, leaflet coaptation-assist device 420 comprises fewer or more tissue-piercing anchors 40, or no tissue-piercing anchors (for example, as described hereinbelow with reference to FIGS. 10A-G, 11A-E, 12A-D, 13A-D, 14A-G, and 15A-C, mutatis mutandis).

[0111] FIGS. 6A-B are schematic illustrations of a leaflet coaptation-assist device 520, in accordance with an application of the present invention, and FIG. 6C is a schematic illustration of leaflet coaptation-assist device 520 implanted in mitral valve 24, in accordance with an application of the present invention. In this configuration, leaflet coaptation-assist device 520 comprises a thick structure 584 having a lower surface 562 that provides a coaptation-assist surface 564. In order to provide its thickness, thick structure 584 may comprise, for example, a solid foam or at least one balloon, which may be inflated with a liquid, such as water, saline, contrast media, glue, foam, and/or blood. As used in the present application, including the claims, the word “solid” in “solid foam” refers to the state of matter, rather than implying any level of rigidity of the foam. For some applications, the solid foam comprises a polymer, such as polyurethane or silicone.

[0112] For some applications, thick structure 584 is curved, such as multi-curved, on ventricular (lower) surface 562, such as with a bi-lobal shape 586 provided by the body of thick structure 584. The curvature provides multiple planes of coaptation for leaflets 22, rather than a single plane along the implantation plane.

[0113] Optionally, thick structure 584 is planar on the upper (atrial) side.

[0114] Optionally, thick structure 584 of leaflet coaptation-assist device 520 has a greatest thickness (typically near the two shorter edges (i.e., near the commissures)) in the atrial-ventricular direction of at least 2 mm (e.g., at least 3 mm), no more than 20 mm, and/or between 2 and 20 mm, e.g., between 3 and 20 mm, and/or a smallest thickness (typically near the center) in the atrial-ventricular direction of at least 1 mm, no more than 5 mm, and/or between 1 and 5 mm.

[0115] FIG. 6D is a schematic illustration of one of tissue anchors 40 implanted in tissue of the native annulus, in accordance with an application of the present invention.

[0116] FIGS. 7A-C are schematic illustrations of a leaflet coaptation-assist device 620, in accordance with an application of the present invention. In this configuration, leaflet coaptation-assist device 420 comprises a convex thick structure 684, with an atrial and ventricular curved shape provided by the body of thick structure 684. In order to provide its thickness, thick structure 684 may comprise, for example, a solid foam or at least one balloon, which may be inflated with a liquid, such as water, saline, contrast media, glue, foam, and/or blood. A ventricular (lower) surface 662 of thick structure 684 provides a coaptation-assist surface 664. The curvature provides multiple planes of coaptation for leaflets 22, rather than a single plane along the implantation plane. Leaflet coaptation-assist device 620 may have any of the features of leaflet coaptation-assist device 520, described hereinabove with reference to FIGS. 6A-D.

[0117] Optionally, thick structure 684 of leaflet coaptation-assist device 620 has a greatest thickness (typically near the center) in the atrial-ventricular direction of at least 6 mm, no more than 40 mm, and/or between 6 and 40 mm, and/or a smallest thickness (typically near the two shorter edges (i.e., near the commissures)) in the atrial-ventricular direction of at least 1 mm, no more than 5 mm, and/or between 1 and 5 mm.

[0118] FIGS. 8 and 9 are schematic illustrations of leaflet coaptation-assist devices 720 and 820, respectively, in accordance with respective applications of the present invention. Leaflet coaptation-assist device 720 and 820 comprise volume filling components. As shown in FIG. 8, the volume filling component of leaflet coaptation-assist device 720 comprises a spindle bead 772, and as shown in FIG. 9, the volume filling component of leaflet coaptation-assist device 720 comprises a spherical shaped bead 872. Such volume filling components are anchored on tethers 770 and 780, respectively, which may be coupled to tissue of the heart by anchoring techniques described herein.

[0119] For some applications, the volume filling components comprise elastomeric balloons, which are configured to be inflated in situ. For other applications, the volume filling components are self-swelling upon delivery.

[0120] Leaflet coaptation-assist device 720 may further comprise sheet 30 and/or tissue anchors 40, such as described hereinabove with reference to FIGS. 1A-B, mutatis mutandis. Leaflet coaptation-assist device 820 may further comprise tissue anchors 40, such as described hereinabove with reference to FIGS. 1A-B, mutatis mutandis.

[0121] FIGS. 10A-D are schematic illustrations of a leaflet coaptation-assist device 920, in accordance with an application of the present invention, and FIGS. 10E-G are schematic illustrations of leaflet coaptation-assist device 920 implanted in mitral valve 24, in accordance with an application of the present invention. In this configuration, leaflet coaptation-assist device 920 may comprise a sheet 930 (as shown), which may implement any of the sheet configurations described herein, or a thick structure (configuration not shown), which may implement any of the thick structure configurations described herein. In either case, a ventricular (lower) surface 962 of the sheet or thick structure provides a coaptation-assist surface 964.

[0122] In this configuration, leaflet coaptation-assist device 920 comprises a non-tissue-piercing anchor, which may comprise one or more (e.g., two or more) ventricular loops 988, which optionally comprises a superelastic material. The one or more ventricular loops 988 extend in a ventricular direction from sheet 930 or thick structure, crossing the native or prosthetic valve in the commissural area. For some applications, the one or more ventricular loops 988 are fixed to the shorter sides of sheet 930 or thick structure. For some applications, the one or more ventricular loops 988 stabilize the device by friction and radial force.

[0123] Optionally, in configurations in which leaflet coaptation-assist device 920 comprises two or more ventricular loops 988, the two or more ventricular loops 988 cross one other, with the crossing located within a ventricular chamber 26 upon implantation of leaflet coaptation-assist device 920, such as shown in FIGS. 10A-G.

[0124] FIGS. 10E-G show leaflet coaptation-assist device 920 implanted in mitral valve 24, with leaflets 22 below the coaptation-assist device, and with the one or more ventricular loops 988 extending within ventricular chamber 26, extending to a ventricular apical area 28.

[0125] FIGS. 11A-E are schematic illustrations of a leaflet coaptation-assist device 1020, in accordance with an application of the present invention. Other than as described below, leaflet coaptation-assist device 1020 is similar to leaflet coaptation-assist device 920, described hereinabove with reference to FIGS. 10A-G. A ventricular (lower) surface 1062 of a sheet 1030 or thick structure provides a coaptation-assist surface 1064. In this configuration, leaflet coaptation-assist device 1020 comprises a non-tissue-piercing anchor that comprises a single ventricular loop 1088, which is optionally fixed to both the shorter sides of sheet 1030 or the thick structure. For some applications, such as shown in FIG. 11D, ventricular loop 1088 is configured to come into contact with one of leaflets 22 at the commissural level and clip the leaflet within ventricular loop 1088 to stabilize the anchoring of leaflet coaptation-assist device 1020.

[0126] FIGS. 12A-D are schematic illustrations of a leaflet coaptation-assist device 1120, in accordance with an application of the present invention. Other than as described below, leaflet coaptation-assist device 1120 is similar to leaflet coaptation-assist device 920, described hereinabove with reference to FIGS. 10A-G. A ventricular (lower) surface 1162 of a sheet 1130 or thick structure provides a coaptation-assist surface 1164. In this configuration, leaflet coaptation-assist device 1120 comprises a non-tissue-piercing anchor that comprises two separate independent, non-crossing ventricular loops 1188A and 1188B, which do not touch one another, and which are typically configured to be positioned ventricularly below the commissural valve level. Typically, ventricular loops 1188A and 1188B are coupled to the shorter sides of sheet 1130 or the thick structure.

[0127] For some applications, such as shown in FIGS. 12C-D, ventricular loops 1188A and 1188B are configured to come into contact with both of leaflets 22 at the commissural level and clip leaflets 22 within the ventricular loops to stabilize the anchoring of leaflet coaptation-assist device 1120.

[0128] FIGS. 13A-D are schematic illustrations of a leaflet coaptation-assist device 1220, in accordance with an application of the present invention. In this configuration, leaflet coaptation-assist device 1220 may comprise a sheet 1230 (as shown), which may implement any of the sheet configurations described herein, or a thick structure (configuration not shown), which may implement any of the thick structure configurations described herein. In either case, a ventricular (lower) surface 1262 of sheet 1230 or the thick structure provides a coaptation-assist surface 1264. In this configuration, leaflet coaptation-assist device 1220 comprises a non-tissue-piercing anchor, which comprises a stent 1290, which is configured to be coupled to an atrial wall, so as to position leaflet coaptation-assist device 1220 at the annular level, at or below the leaflet hinge line of leaflets 22, optionally depending of the height of coupling of stent 1290 above the atrioventricular valve.

[0129] FIGS. 14A-F are schematic illustrations of a leaflet coaptation-assist device 1320, in accordance with an application of the present invention, and FIG. 14G is a schematic illustration of leaflet coaptation-assist device 1320 implanted in mitral valve 24, in accordance with an application of the present invention. Other than as described below, leaflet coaptation-assist device 1320 is similar to leaflet coaptation-assist device 1220, described hereinabove with reference to FIGS. 13A-D. A ventricular (lower) surface 1362 of a sheet 1330 or a thick structure provides a coaptation-assist surface 1364. In this configuration, leaflet coaptation-assist device 1320 is configured to position the sheet or thick structure below the annular level, so to favorite the below leaflet coaptation with coaptation-assist surface 1364. For example, a stent 1390 may comprise ventricular extensions 1391, which extend ventricularly to support sheet 1330 or the thick structure below the annular level.

[0130] FIGS. 15A-B are schematic illustrations of a leaflet coaptation-assist device 1420, in accordance with an application of the present invention, and FIG. 15C is a schematic illustration of leaflet coaptation-assist device 1420 implanted in a tricuspid valve 1425, in accordance with an application of the present invention. Leaflet coaptation-assist device 1420 is configured to treat tricuspid valve 1425 by promoting valve coaptation of the leaflets of tricuspid valve 1425. To this end, leaflet coaptation-assist device 1420 comprises a sheet 1430 that is shaped so as to define three spokes 1433 extending radially outward from a central hub region 1435. (It is to be understood that the word “spokes” does not imply that sheet 1430 further comprises a wheel at the outer ends of the spokes.) Alternatively, leaflet coaptation-assist device 1420 comprises a thick structure (configuration not shown), which may implement any of the thick structure configurations described herein in combination with the three-spoke shape. A ventricular (lower) surface 1462 of sheet 1430 or the thick structure provides a coaptation-assist surface 1464.

[0131] Typically, the three spokes 1433 are evenly distributed around the central hub region 1435, i.e., at an angle of 120 degrees with respect to one another. Optionally, sheet 1430 is rotationally symmetric, such as shown.

[0132] For some applications, the three spokes 1433 are collectively shaped so as to define a deltoid curve (e.g., three straight short sides and three curved longer sides).

[0133] For some applications, radially-outward ends of spokes 1433 include respective stiffened portions 1460, which may be formed as described hereinabove with reference to FIGS. 2A-D for stiffened portions 160.

[0134] Typically, the stiffened radial ends of sheet 1430 connect the sheet to the annular level.

[0135] For some applications, leaflet coaptation-assist device 1420 comprises a non-tissue-piercing anchor, which may comprise one or more (e.g., two or more) ventricular loops 1488, which optionally comprises a superelastic material. The one or more ventricular loops 1488 extend in a ventricular direction from sheet 1430 or the thick structure through the commissural spaces, and stabilize within a ventricular chamber 1492 and position the device at the leaflets coaptation level. Alternatively, for other applications, leaflet coaptation-assist device 1420 comprises tissue-piercing anchors, such as described hereinabove, or does not comprise any anchors.

[0136] In some applications of the present invention, a method is provided for promoting valve coaptation in a patient. The method comprises identifying incomplete coaptation of leaflets of tricuspid valve 1425, the leaflets selected from the group consisting of: native leaflets and prosthetic leaflets. Leaflet coaptation-assist device 1420 is implanted, the device including sheet 1430 shaped so as to define three spokes 1433 extending radially outward from central hub region 1435, such that coaptation-assist surface 1646 defined by lower surface 1642 of sheet 1430 is located at or below the leaflet hinge line and contacts an atrial side of the leaflets during systole, thereby enhancing leaflet coaptation.

[0137] Although the leaflet assist devices described herein are generally described in the context of an atrioventricular valve, they can be used to enhance the performance of any of the valves in the circulatory system, including a venous valve, e.g., a peripheral venous valve.

[0138] While preferred embodiments of the present invention have been shown and described herein, it will be obvious to those skilled in the art that such embodiments are provided by way of example only. Numerous variations, changes, and substitutions will now occur to those skilled in the art without departing from the invention. It should be understood that various alternatives to the embodiments of the invention described herein may be employed in practicing the invention. It is intended that the following claims define the scope of the invention and that methods and structures within the scope of these claims and their equivalents be covered thereby.

[0139] In an embodiment, techniques and apparatus described in one or more of the following applications, which are assigned to the assignee of the present application and are incorporated herein by reference, are combined with techniques and apparatus described herein: [0140] PCT Publication WO 2014/207575 to Schewel [0141] PCT Publication WO 2018/142217 to Kuck et al. [0142] PCT Publication WO 2020/148755 to Guidotti et al. [0143] U.S. Provisional Application 61/956,683, filed Jun. 14, 2013 [0144] U.S. Provisional Application 61/963,330, filed Dec. 2, 2013 [0145] U.S. Provisional Application 61/982,307, filed Apr. 21, 2014 [0146] U.S. Provisional Application 62/455,427, filed Feb. 6, 2017 [0147] U.S. Provisional Application 62/570,336, filed Oct. 10, 2017 [0148] U.S. Provisional Application 62/792,092, filed Jan. 14, 2019 [0149] U.S. Provisional Application 62/884,404, filed Aug. 8, 2019

[0150] It will be appreciated by persons skilled in the art that the present invention is not limited to what has been particularly shown and described hereinabove. Rather, the scope of the present invention includes both combinations and subcombinations of the various features described hereinabove, as well as variations and modifications thereof that are not in the prior art, which would occur to persons skilled in the art upon reading the foregoing description.