Prosthetic heart valves
Disclosed are techniques for construction of prosthetic heart valves, particularly techniques for attachment of scalloped edges of valvular leaflets to struts of mechanical frames using sutures and/or other materials as intermediate coupling members. In some embodiments, the scalloped edges of the leaflets are coupled to the segments of the struts of the frame via suture loops that are oriented transverse to the scalloped edges of the leaflets. In some embodiments, central portions of scallop line segments are attached to the scalloped edges of the leaflets and are not attached to the frame. In some embodiments, strut segments are tapered to limit translation of suture loops. In some embodiments, a cloth strip couples the scalloped edges of the leaflets to frame struts. In some embodiments, the scalloped edge is attached to adjacent segments of intersecting struts via sliding suture loops, where the adjacent segments join at a common pivot joint.
1 . A prosthetic heart valve comprising:
a radially expandable and collapsible annular frame comprising a plurality of intersecting struts coupled together at pivot joints, wherein radial expansion or contraction of the annular frame causes the intersecting struts to pivot relative to one another at the pivot joints; and
a valvular structure mounted within the frame that regulates blood flow through the prosthetic heart valve, the valvular structure comprising leaflets;
wherein the leaflets are coupled to the frame at lateral commissure ends of the leaflets and along scalloped edges of the leaflets that extend between the lateral commissure ends; and
wherein the scalloped edges of the leaflets are coupled to segments of the struts of the frame via suture loops, and the strut segments to which the suture loops are coupled are oriented transverse to the scalloped edges of the leaflets.
2 . The valve of claim 1 , wherein the coupling of the scalloped edges of the leaflets to strut segments that are oriented transverse to the scalloped edges allows movement of the scalloped edges relative to the strut segments via the suture loops sliding along the strut segments during radial expansion and compression of the frame.
3 . The valve of claim 1 , wherein during systole and diastole, anatomical forces acting on the leaflets at attachment points to the struts along the scalloped edges is substantially perpendicular to the suture loops, thereby inhibiting undesirable abrasion of the suture loops and the leaflets.
4 . The valve of claim 1 , wherein the scalloped edge of each leaflet is coupled via suture loops to segments of at least six different struts of the frame; and
wherein the at least six different struts comprises three parallel strut segments on one side of the scalloped edge and another three parallel strut segments on a second side of the scalloped edge.
5 . The valve of claim 1 , wherein the strut segments to which the suture loops are coupled are oriented substantially perpendicular to the scalloped edges of the leaflets.
6 . The valve of claim 1 , wherein each of the struts of the frame is pivotably coupled to three or more other struts of the frame at respective mechanical pivot joints, such that the struts can pivot relative to one another without deforming; and
wherein each strut comprises at least three strut segments, with each strut segment extending between two adjacent mechanical pivot joints.
7 . The valve of claim 1 , wherein the strut segments are tapered such that they reduce in width from an inflow end of the frame toward an outflow end of the frame;
wherein the leaflets are coupled to the tapered strut segments via suture loops that extend around the tapered strut segments, such that the suture loops are large enough to fit around narrower ends of the tapered strut segments and small enough to not fit around wider ends of the tapered strut segments; and
wherein the suture loops are configured to slide along the tapered strut segments from the narrower ends toward the wider ends and become frictionally self-locked at an intermediate location along the tapered strut segments where the suture loops are equal in circumference to the strut segments.
8 . A prosthetic heart valve comprising:
a radially expandable and collapsible annular frame comprising a plurality of intersecting struts coupled together at pivot joints, wherein radial expansion or contraction of the annular frame causes the intersecting struts to pivot relative to one another at the pivot joints; and
a valvular structure mounted within the frame that regulates blood flow through the prosthetic heart valve, the valvular structure comprising three leaflets; and
a scallop line infrastructure that comprises three scallop line elements, with each of the three scallop line elements being attached to a scalloped edge of a respective one of the three leaflets;
wherein each of the scallop line elements comprises two opposing end portions and a central portion between the two opposing end portions, wherein the end portions are attached to the frame along with lateral ends of the leaflets at commissures, and wherein the central portions of the scallop line elements are attached to the scalloped edges of the leaflets and are free of the frame;
wherein the scalloped edges of the leaflets are coupled to segments of the struts of the frame via suture loops, and the strut segments to which the suture loops are coupled are oriented transverse to the scalloped edges of the leaflets.
9 . The valve of claim 8 , wherein the scallop line elements are formed of a rigid material, selected from the group consisting of a metal and a metal alloy and are resiliently deformable to resist radially inward displacement of the scalloped edges of the leaflets.
10 . The valve of claim 8 , wherein the scallop line elements are formed of a soft material selected from the group consisting of a short skirt, cloth, and string.
11 . The valve of claim 8 , wherein the scallop line elements are flexible to allow the central portions of the scallop line elements to deform from a generally U shape to a generally V shape during radial compression of the frame while the end portions of the scallop line elements move toward each other.
12 . The valve of claim 8 , wherein each of the struts of the frame is pivotably coupled to three or more other struts of the frame at respective mechanical pivot joints, such that the struts can pivot relative to one another without deforming; and
wherein each strut comprises at least three strut segments, with each strut segment extending between two adjacent mechanical pivot joints.
13 . The valve of claim 8 , wherein the strut segments are tapered such that they reduce in width from an inflow end of the frame toward an outflow end of the frame;
wherein the leaflets are coupled to the tapered strut segments via suture loops that extend around the tapered strut segments, such that the suture loops are large enough to fit around narrower ends of the tapered strut segments and small enough to not fit around wider ends of the tapered strut segments; and
wherein the suture loops are configured to slide along the tapered strut segments from the narrower ends toward the wider ends and become frictionally self-locked at an intermediate location along the tapered strut segments where the suture loops are equal in circumference to the strut segments.
14 . The valve of claim 8 , wherein the central portions of the scallop line elements extend between two adjacent strut segments of two intersecting struts.
15 . A prosthetic heart valve comprising:
a radially expandable and collapsible annular frame comprising a plurality of intersecting struts coupled together at pivot joints, wherein radial expansion or contraction of the annular frame causes the intersecting struts to pivot relative to one another at the pivot joints, and wherein the struts of the frame comprise plural strut segments between the pivot joints; and
a valvular structure mounted within the frame that regulates blood flow through the prosthetic heart valve, the valvular structure comprising plural leaflets that each have commissure ends and scalloped edges extending between the commissure ends;
wherein each scalloped edge is coupled to adjacent segments of intersecting struts via sliding suture loops, the adjacent segments joining at a common pivot joint of the pivot joints, wherein the sliding suture loops are permitted to slide along the adjacent segments both toward and away from the common pivot joint.
16 . The valve of claim 15 , wherein during radial frame expansion, the sliding suture loops slide along the adjacent segments toward the common pivot joint.
17 . The valve of claim 15 , wherein during radial frame contraction, the sliding suture loops slide along the adjacent segments away from the common pivot joint.
18 . The valve of claim 15 , wherein each of the struts of the frame is pivotably coupled to three or more other struts of the frame at respective mechanical pivot joints, such that the struts can pivot relative to one another without deforming; and
wherein each strut comprises at least three strut segments, with each strut segment extending between two adjacent mechanical pivot joints.
19 . The valve of claim 15 , wherein the strut segments are tapered such that they reduce in width from an inflow end of the frame toward an outflow end of the frame;
wherein the leaflets are coupled to the tapered strut segments via suture loops that extend around the tapered strut segments, such that the suture loops are large enough to fit around narrower ends of the tapered strut segments and small enough to not fit around wider ends of the tapered strut segments; and
wherein the suture loops are configured to slide along the tapered strut segments from the narrower ends toward the wider ends and become frictionally self-locked at an intermediate location along the tapered strut segments where the suture loops are equal in circumference to the strut segments.
20 . The valve of claim 15 , further comprising a scallop line infrastructure that comprises three scallop line elements, with each of the three scallop line elements being attached to a scalloped edge of a respective one of the leaflets.