Prosthetic heart valve with reduced native annulus

Abstract

A prosthetic heart valve configured to expand within a native valve annulus, engage surrounding tissue, and contract the tissue inwardly to enhance contact between the tissue and the valve. The heart valve can have a structural valve stent having an outer constriction structure with a tissue engaging member. The collapsible structure may be intrinsic or extrinsic. An intrinsic form includes a plurality of arms arranged to contract inwardly toward a central valve portion, or a fabric structure having a tissue anchor and surrounding an inner valve member can be tightened to pull the tissue inwardly.

Description

[0001] Cross-reference to priority application

[0002] This application claims the benefit of U.S. Provisional Application No. 63 / 352,777, filed on June 16, 2022, the entire contents of which are hereby incorporated by reference. Technical Field

[0003] The present application generally relates to expandable prosthetic heart valves, such as replacement mitral or tricuspid heart valves, that better secure to and reshape the valve annulus. Background Art

[0004] In vertebrates, the heart is a hollow muscular organ with four pumping chambers: left and right atria and left and right ventricles, each with its own one-way valve. The natural heart valves are identified as the aortic, mitral, tricuspid, and pulmonary valves, each with flexible leaflets that engage each other to prevent reverse flow.

[0005] Prostheses exist to correct problems associated with damaged heart valves. For example, mechanical and tissue-based heart valve prostheses can be used to replace damaged native heart valves. Recently, a lot of effort has been devoted to developing replacement heart valves, particularly tissue-based replacement heart valves, which can be delivered with less trauma to the patient than by open heart surgery. Replacement valves are designed to be delivered by minimally invasive surgery and even percutaneous surgery. Such replacement valves typically include a tissue-based valve body that is connected to an expandable frame that is then delivered by a catheter or other such access tube.

[0006] Expandable valves sometimes do not seal as well against the native annulus as a surgical valve that is sutured in place, resulting in paravalvular leaks. Additionally, expandable valves often push radially outward against the surrounding annulus, which can exacerbate underlying disease and reshape the heart in an undesirable manner. Further, replacement valves can sometimes contact surrounding tissue (e.g., the ventricular wall) and have adverse effects. Therefore, there is a need for expandable heart valves that can pull surrounding tissue inward to form a better seal, reshape the heart in a more favorable manner, and avoid contact with the heart wall. Summary of the invention

[0007] Expandable prosthetic heart valves, such as replacement mitral or tricuspid heart valves, are disclosed herein that better secure to the valve annulus and, in some cases, reshape the valve annulus. The expandable prosthetic heart valve may have a structure that anchors to the surrounding annular tissue and pulls the tissue inward, typically reshaping the annulus and potentially the ventricle beneath the annulus. Advantages of these features include minimizing the device profile required to treat very large annuli, providing an adaptable platform to treat a range of annuli with one or very few valve sizes, and depending on the anchoring mechanism, the procedure may be guided largely via fluoroscopy.

[0008] An example of a prosthetic heart valve assembly is for replacing a natural mitral valve or tricuspid valve. The prosthetic heart valve assembly includes a self-expandable stent having a body having an inlet end portion and an outlet end portion. The stent may be made of a shape memory material (such as nitinol). The valve portion is positioned within a channel of the body for allowing blood to flow through the channel in only one direction, thereby replacing the function of a natural valve. At least one anchor and preferably a plurality of anchors are provided along the outer surface of the prosthetic heart valve assembly for engaging surrounding tissue. The prosthetic heart valve assembly is suitable for reducing the diameter of the natural valve ring by pulling the surrounding tissue inward. Reducing the diameter of the valve ring can provide many advantages, such as treating underlying diseases (e.g., performing annuloplasty), reducing the device profile in the body, and creating a better seal around the outside of the device.

[0009] The prosthetic heart valve assembly may include an annular flange extending radially outward from the body (such as from the inlet end portion). One or more tissue engagement anchors may be disposed on the annular flange, such as along the lower surface or on the periphery. The anchor may include a barb, a spiral screw, or any other suitable tissue engagement mechanism. The annular flange may be capable of transforming from a large diameter to a small diameter for contracting the annulus of a natural valve. In one embodiment, the annular flange may include a plurality of radially extending arms, each of which is configured to be reduced in length for pulling tissue inward, thereby contracting the annulus of a natural valve. The reduction in the length of the arm may be achieved by using a bioresorbable material that initially maintains the arm in an extended state and is reabsorbed in vivo to allow the arm to be transformed into a shortened state.

[0010] In a prosthetic heart valve assembly having an annular flange, a tightening mechanism may be connected to each of the anchors. The tightening mechanism may be adapted to pull the anchors radially inwardly for contracting the annulus of the native valve.

[0011] In a prosthetic heart valve assembly having an annular flange, the anchor may be deployed separately from the heart valve such that the anchor is not integrated into the heart valve.

[0012] In a prosthetic heart valve assembly having an annular flange, the annular flange may be coupled to the body and configured to decrease in diameter during radial expansion of the body.

[0013] In a prosthetic heart valve assembly having an annular flange, the annular flange may include a plurality of helically arranged arms having ends when expanded that collectively define a diameter D 1 The circle of rotation of the valve portion about its axis draws the arms inwardly so that the ends together define a collapsed diameter D 2 .

[0014] The prosthetic heart valve assembly may also include one or more ventricular anchors extending from the body (such as from the outlet end portion). The ventricular anchors may be shaped to capture the natural valve leaflets between the ventricular anchors and the body of the stent. Alternatively, the ventricular anchors may be shaped to be placed within the natural valve leaflets and may have an outer surface for engaging surrounding tissue. In a preferred embodiment, the ventricular anchors transform (i.e., flip) from a generally straight shape to a curved shape when deployed.

[0015] Another example of a prosthetic heart valve assembly includes: a stent having a body; a valve portion positioned within a channel of the body; and a plurality of anchors disposed along an outer surface of the stent for engaging surrounding tissue. The stent may be made of a shape memory material such as nitinol. The stent may be adapted to be radially over-expanded by an expansion mechanism to a diameter greater than its shape setting diameter to ensure that the anchors securely engage and / or penetrate the surrounding tissue. The expansion mechanism is then removed to allow the stent to return to its shape setting diameter. As the stent returns to its shape setting diameter (i.e., decreases in diameter), it pulls the surrounding tissue inward.

[0016] The expansion mechanism may be a balloon or any other suitable mechanism for temporarily expanding the stent. The stent may include an annular flange extending radially outward from the body, wherein the anchor is disposed along a surface of the annular flange. Alternatively, the stent may include at least one ventricular anchor extending from the body. The ventricular anchor is desirably shaped to capture natural valve leaflets between the ventricular anchor and the body of the stent. Further, the stent may include an annular flange extending radially outward from an inlet end portion of the body and at least one ventricular anchor, the at least one ventricular anchor being used to capture natural valve leaflets between the ventricular anchor and the body of the stent. A fabric seal may cover at least a portion of the stent.

[0017] Another prosthetic heart valve assembly can be constructed to replace a natural mitral valve or tricuspid valve. The prosthetic heart valve assembly includes a self-expandable valve stent made of a shape memory material and covered with fabric, the valve stent having a tubular valve portion and a peripheral flange, the tubular valve portion having an inlet end portion and an outlet end portion, the peripheral flange being formed by an array of struts or arms extending radially outward from the inlet end portion and connected to the inlet end portion when expanded, the array having an inherent radial contraction mechanism and a tissue engaging member. The valve portion is positioned within a channel of the body, wherein the valve portion includes a plurality of leaflets made of pericardium, wherein the valve portion allows blood to flow through the channel in one direction to replace the function of a natural valve. The prosthetic heart valve assembly is adapted to anchor the tissue engaging member to tissue surrounding the valve annulus to shrink the valve annulus when deployed, thereby radially contracting the valve annulus of the natural valve.

[0018] The array may include flap-like struts coupled to the valve portion such that expansion of the valve portion causes radial contraction of the struts. Alternatively, the array may include struts configured to curl outwardly toward the valve portion and then inwardly when an external constraint around the valve is removed from the inflow end, the struts having barbs on the outer ends defining tissue engaging members.

[0019] The array may include a plurality of radially extending arms, each of which has a contraction mechanism for reducing the length of the built-in arm. The contraction mechanism may include an extension structure that is biased to a contracted length and is held extended by a bioresorbable suture. The contraction mechanism may alternatively include an extension structure that is biased to a contracted length and is held extended by a reinforcing wire. Only some of the radially extending arms have tissue engaging members on the some of the radially extending arms, and the radially extending arms may have different lengths.

[0020] In yet another embodiment, the array may include a plurality of helically arranged arms having ends when expanded that collectively define a diameter D 1 The circle of rotation of the valve portion about its axis draws the arms inwardly so that the ends together define a collapsed diameter D 2 .

[0021] In another variation, the valve stent may have an outer anchoring stent and an inner valve stent, and the array includes a plurality of radial arms extending from a strut connected only at the lower end of the anchoring stent, wherein after the barbs are anchored at the ends of the radial arms, rotation of the anchoring stent causes the struts to rotate into a spiral shape and pull the ends inward, and the inner valve stent then expands within the outer anchoring stent.

[0022] Another example of a prosthetic heart valve assembly for replacing a natural mitral valve or tricuspid valve includes a self-expandable valve stent made of a shape memory material and covered with fabric, wherein the valve stent has a tubular valve portion having an inlet end portion and an outlet end portion. An arm array extends radially outward from the outlet end portion of the valve portion and is connected to the outlet end portion, and can be configured to bend toward the inlet end portion (e.g., 180°). The array has an inherent radial contraction mechanism and a tissue engagement member. The valve portion is positioned in a channel of the main body, wherein the valve portion includes a plurality of leaflets made of pericardium, wherein the valve portion allows blood to flow through the channel in one direction to replace the function of a natural valve. The prosthetic heart valve assembly is suitable for anchoring the tissue engagement member to the natural valve leaflets to pull the leaflets toward the tubular valve portion when deployed.

[0023] In another example, the intrinsic radial contraction mechanism may include a reinforcing tube mounted around a lower U-bend on each of the arms, the reinforcing tube having a radius of curvature larger than the U-bend to force the arms to an outward position, and the reinforcing tube being bioresorbable after a period of time in vivo to allow the arms to return to a radially inward shape.

[0024] In another example, the intrinsic radial contraction mechanism may include one or more reinforcement plugs mounted within a recessed portion on the inner radius of each of the arms, which retain the arms in an outward position and are bioresorbable after a period of time in vivo to allow the arms to return to a radially inward shape.

[0025] A system for contracting an implantable prosthetic heart valve, the implantable prosthetic heart valve being configured for implantation at a native mitral or tricuspid valve annulus, the system comprising: a heart valve having a self-expandable valve stent covered with fabric, the valve stent having a tubular valve portion and a valve member in which a valve leaflet is mounted, the valve further having a peripheral flange when expanded, the peripheral flange comprising a substantially annular array of fabric-covered struts or arms extending radially outward from and connected to an inflow end of the valve portion, the array having a tissue engaging member configured to grasp and anchor to tissue surrounding the valve annulus. An external radial contraction mechanism is provided for pulling tissue surrounding the valve annulus inward after deployment of the tissue engaging member. The external radial contraction mechanism may include a flexible band having a length sufficient to extend from outside the body and being threaded to connect and slide through each of the tissue engaging members in the tissue engaging members, wherein tension on the band contracts the array and pulls tissue surrounding the valve annulus inward.

[0026] The tissue engaging member may include a valve anchor that is separate from the peripheral flange and deployed through the peripheral flange once the heart valve is seated at the valve annulus.

[0027] The array may include a plurality of radially extending arms, and the tissue engaging members may include anchoring barbs secured to outer ends of at least some of the arms.

[0028] Another system for collapsing an implantable prosthetic heart valve, which is constructed for implantation at the annulus of a native mitral or tricuspid valve, the other system comprising: a heart valve having a self-expandable valve stent covered with fabric, the valve stent having a tubular valve portion and a valve member in which leaflets are mounted, the valve further having a peripheral flange when expanded, the peripheral flange comprising a generally annular array of fabric-covered struts or arms extending radially outward from an inflow end of the valve portion and connected to the inflow end, the array having a tissue engaging member constructed to grasp and anchor to tissue surrounding the valve annulus, and wherein the peripheral flange is radially separated with free ends exposed on the inflow side of the peripheral flange. An external radial contraction mechanism is provided for pulling tissue around the valve annulus inward after deployment of the tissue engaging member, the external radial contraction mechanism comprising a pair of flexible tethers having a length sufficient to extend from outside the body and being threaded to connect and slide through a pair of radially spaced anchors, the pair of radially spaced anchors being embedded in the valve annulus tissue through a peripheral flange and extending circumferentially along the peripheral flange to attach to the free end of the peripheral flange, wherein tension on the tethers contracts the peripheral flange and pulls tissue around the valve annulus inward.

[0029] Another system for contracting an implantable prosthetic heart valve configured for implantation at a native mitral or tricuspid valve annulus includes a heart valve having a fabric-covered self-expandable valve support having a tubular valve portion and a valve member having leaflets mounted therein, the valve further having a peripheral flange when expanded, the peripheral flange comprising a substantially annular array of fabric-covered struts or arms extending radially outward from and connected to an inflow end of the valve portion. At least one tissue anchor is separate from the prosthetic heart valve and configured to be embedded in tissue surrounding the valve annulus. An external radial contraction mechanism is configured to pull tissue surrounding the valve annulus inward after deployment of the tissue anchor, the external radial contraction mechanism comprising a plurality of flexible tethers having a length sufficient to extend from outside the body, extend through the peripheral flange, and extend radially outward to be secured to the tissue anchor, wherein tension contraction on the tethers pulls tissue surrounding the tissue anchor and the peripheral flange inward.

[0030] A collapsible prosthetic heart valve for implantation at a native mitral or tricuspid valve annulus, the collapsible prosthetic heart valve comprising: a self-expandable valve stent covered with fabric, the valve stent having a tubular valve portion and a valve member in which leaflets are mounted, the valve further having a fabric-covered arm array extending radially outward from and connected to the outflow end of the valve portion and bending 180° toward the inflow end, the array having a tissue-engaging member configured to grasp and anchor the leaflets attached to the valve annulus. An external radial contraction mechanism configured to pull the leaflets attached to the valve annulus inward after the tissue-engaging member is deployed, the external radial contraction mechanism comprising a flexible band having a length sufficient to extend from outside the body and being threaded to connect and slide through and completely surround the fabric covering the array, wherein tension on the band contracts the fabric-covered array and pulls the leaflets inward.

[0031] Another collapsible prosthetic heart valve for implantation at the annulus of a native mitral or tricuspid valve, the collapsible prosthetic heart valve comprising: a self-expandable valve stent covered with fabric, the valve stent having a tubular valve portion and a valve member in which leaflets are mounted, the valve further having a fabric-covered outer tube, the fabric-covered outer tube being radially spaced outward from the valve portion and connected to the valve portion by an upper flexible skirt and a lower flexible skirt, the outer tube having a tissue-engaging member configured to grasp and anchor the leaflets attached to the valve annulus. An external radial contraction mechanism configured to pull the leaflets attached to the valve annulus inward after the tissue-engaging member is deployed, the external radial contraction mechanism comprising a flexible band having a length sufficient to extend from outside the body and being threaded to connect and slide through and completely around the fabric covering the outer tube, wherein tension on the band contracts the fabric-covered outer tube and pulls the leaflets inward.

[0032] A method for contracting a prosthetic heart valve implanted in a natural mitral or tricuspid valve annulus, the method comprising the following steps: providing a heart valve having a self-expandable valve stent covered with fabric, the self-expandable valve stent having a tubular valve portion and a valve member in which a leaflet is mounted, the valve portion having a relaxed expanded size, the valve further having a peripheral flange, the peripheral flange comprising a substantially annular array of fabric-covered struts or arms extending radially outward from an inflow end of the valve portion and connected to the inflow end, the array having a tissue engaging member, the tissue engaging member being constructed to grasp and anchor to tissue around the valve annulus. Curling the heart valve around a balloon and constraining it in a contracted state within an access sheath. Advancing the heart valve in a contracted state within the access sheath toward the valve annulus. Expelling the heart valve from the access sheath, preferably within the valve annulus. Inflating the balloon beyond the expanded size of the valve portion of the valve stent, thereby anchoring or embedding the tissue engaging member into tissue around the valve annulus. The balloon is then deflated to allow the valve portion to collapse and pull the peripheral flange inward.

[0033] Another method of collapsing a prosthetic heart valve implanted at a native mitral or tricuspid valve annulus includes providing a self-expandable valve stent covered with fabric, the valve stent having a tubular valve portion and a valve member in which leaflets are mounted, the valve portion having a relaxed expanded size, the valve further having a fabric-covered arm array extending radially outward from and connected to the outflow end of the valve portion and bending toward the inflow end, the array having a tissue-engaging member configured to grasp and anchor to the leaflets attached to the valve annulus. The heart valve is prepared for implantation by curling the heart valve around a balloon and constraining the heart valve in a collapsed state within an access sheath. The heart valve in a collapsed state within the access sheath is advanced to the valve annulus. Within the valve annulus, the heart valve is released from the access sheath and the balloon is inflated to over-expand the valve portion of the valve support (i.e., beyond its shape setting diameter), thereby anchoring the tissue engaging members into the valve leaflets. The balloon is then deflated to allow the valve portion to contract to its expanded size and pull the array inward.

[0034] A further understanding of the nature and advantages of the present invention will become apparent by reference to the remaining portions of the specification and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The features and advantages of the present invention will be appreciated as they become better understood with reference to the specification, claims and accompanying drawings, in which:

[0036] Figure 1A is a cross-sectional view of a human heart in the systolic phase. Figure 1Bis the same view of a heart showing an enlarged (dilated) left ventricle, commonly referred to as dilated cardiomyopathy (DCM), but Figure 1C is the same view of the heart showing an enlarged right ventricle (often leading to functional tricuspid regurgitation);

[0037] Figure 2A is a partial cross-sectional view through the left side of the heart showing the mitral valve and annulus above the left ventricular structures, and Figure 2B is a plan view of the mitral valve, showing the commonly known nomenclature of the annulus and leaflets;

[0038] Figure 3A It is the process of implanting the expandable prosthetic heart valve of the present application and before the final step of deployment. Figure 2A The partial cross-sectional view in FIG. Figure 3B is the same view after the final step of radial contraction anchoring to the outer skirt of the mitral annulus;

[0039] FIG. 4A to FIG. 4C yes Figure 3A and Figure 3B Perspective and orthogonal views of an exemplary valve stent for a prosthetic heart valve shown without an outer fabric covering and valve leaflets; Perspective and orthogonal views of an exemplary valve stent for a prosthetic heart valve shown without an outer fabric covering and valve leaflets;

[0040] Figure 5 yes FIG. 4A to FIG. 4C A flat view of the valve stent;

[0041] FIG. 6A to FIG. 6C are sequential views showing only the valve stent being ejected from the access tube to illustrate the deployment steps thereof;

[0042] Figure 7 is a perspective view of an alternative expandable prosthetic heart valve of the present application having an upper peripheral flange and showing a plurality of anchors prior to deployment through the flange;

[0043] Fig. 8A is a cross-sectional view through the left ventricle showing the final steps of deployment within the mitral annulus prior to deployment Figure 7 expandable prosthetic heart valve, and Figure 8B is the same view after the final step of radially contracting the peripheral flange anchored to the mitral annulus;

[0044] Fig.9A is a perspective view of a further expandable prosthetic heart valve having an upper peripheral flange and showing a plurality of anchors deployed therein, and Fig. 9B The final step of circumferentially tightening the peripheral flange to cause it to contract radially is shown;

[0045] Fig. 10Ais a front view of an alternative heart valve stent of the present application having a tubular valve portion and an upper peripheral flange with anchoring barbs, and Fig. 10B One example of an anchoring barb is shown;

[0046] Fig. 10C is with Fig. 10A A front view of a valve stent similar to the valve stent in FIG. 1 , the valve stent having a body and an upper peripheral flange and a ventricular anchor extending from a lower end of the body, and Fig. 10D A valve stent implanted at the mitral valve annulus is shown;

[0047] Fig.11A and Fig. 11B are two views illustrating steps of deploying the valve stent of FIG. 10 , wherein expansion of the central portion of the valve stent results in radial contraction of the upper peripheral flange;

[0048] FIG. 12A to FIG. 12C are sequential views showing further valve stents being ejected from the access tube to illustrate the steps of their deployment;

[0049] Fig.13A and Fig. 13B are top plan and side views of an exemplary expanded prosthetic heart valve of the present application;

[0050] Fig. 13C yes Fig.13A An enlarged portion of the embodiment of the invention illustrates a particular configuration of its retracted arms, and Fig.13D is an enlarged portion thereof, illustrating the contraction mechanism;

[0051] Fig.14 is a top plan view of an upper peripheral flange of an exemplary bracket of the present application, and Fig.14A and Fig. 14B shows the actuation of one of its radial arms before and after radial contraction;

[0052] Fig. 14C Collapsible radial arms with reinforcing members formed as bioresorbable rods or bars are shown;

[0053] Fig.15A is similar in structure to Fig.13A A top plan view of an exemplary prosthetic heart valve having a Fig.14 The stent frame peripheral flange in the similar stent frame peripheral flange, while Fig. 15B is a view of a heart valve after radial contraction of the peripheral flange;

[0054] Fig.16A and Fig. 16B is a top plan view of another exemplary valve support having a radially constricted peripheral flange with a series of outer flaps;

[0055] Fig.17A and Fig. 17B is a top plan view of another exemplary valve stent having a radially constricted peripheral flange with a series of spiral radial arms;

[0056] 18A to 18C is a schematic elevational view of a two-part expandable prosthetic heart valve stent assembly of the present application, showing several steps of its deployment;

[0057] Fig.19 is a front view of another valve support of the present application having radially retractable arms around the upper periphery, and Fig.19A An example of retracting one of the arms using a ratchet mechanism is shown;

[0058] Fig. 20A and Fig. 20B are perspective views of an outer fabric structure of an expandable prosthetic heart valve of the present application that can be used to collapse both in an initial deployment configuration and in a collapsed configuration, respectively;

[0059] Fig.21 A prosthetic heart valve is installed in Fig. 20A a perspective view of an assembly of an outer fabric structure;

[0060] Fig.22A and Fig. 22B yes Fig.21 A top plan view of the assembly before and after radial contraction of the outer fabric structure;

[0061] Fig.23A is a front view of another valve stent with radially retractable arms of the present application, Fig. 23B is an enlarged view of the retraction mechanism, and Fig.23C and Fig.23D is a schematic diagram illustrating its operation;

[0062] Fig.24 is a front view of another valve stent of the present application having outer arms offset radially inwards;

[0063] Fig.25A and Fig.25B yes Fig.24 Views of one of the arms of a valve stent before and after release of a temporary measure holding the arm outward;

[0064] Fig.26A and Fig.26B yes Fig.24 Views of one of the arms of a valve stent in FIG. 1 before and after release of another temporary measure holding the arm outward;

[0065] Fig. 27is a front view of another valve stent of the present application having an outer arm with an active tissue anchor, and Fig.27A is an enlarged view of one of the active tissue anchors;

[0066] FIG. 28A to FIG. 28C is a top plan view of one of the active tissue anchors showing several stages of deployment;

[0067] Fig.29 is a partial cross-sectional view through the left side of the heart showing the mitral valve and annulus with tissue anchors pre-installed therein and an expanded prosthetic heart valve advanced along a suture array down to the annulus;

[0068] Fig.30 The expanded prosthetic valve is shown advanced almost down to the annulus, causing the pre-installed tissue anchors to be pulled inward;

[0069] Fig.31A and Fig.31B illustrates engagement between a flat clip on a peripheral flange of a heart valve and one of the tissue anchors;

[0070] Fig.32A The valve stent is shown held in an expanded state by a delivery balloon adjacent to the target annulus, and Fig.32B The implanted position of the valve stent within the annulus is shown, with the balloon removed to allow the annulus to collapse;

[0071] Fig.33A Another type of valve stent is shown maintained in an expanded state by a delivery balloon adjacent to the target annulus, while Fig.33B The implanted position of the valve stent within the annulus is shown, with the balloon removed to allow the annulus to collapse;

[0072] Fig.34 is a perspective view of a further heart valve stent having a tubular valve portion and an upper peripheral flange formed by radially extending arms with anchoring barbs at their ends, and Fig.35 is a partial enlarged view of a segment of a valve stent with anchoring arms;

[0073] FIG. 36A to FIG. 36C The use of a tubular sheath for delivery and implantation of Fig.34 The order of the stented heart valve;

[0074] Fig.37A and Fig.37B An example of a suture activated by tension Fig.34 A configuration of the anchoring barbs of the stent;

[0075] Fig.38 and Fig.39Illustrated Fig.34 Two alternative configurations of the anchoring barbs of the stent;

[0076] Fig.40 is with Fig.34 A perspective view of a heart valve stent similar to the heart valve stent in but having anchoring barbs on only some of the radially extending arms, while Fig.40A is an enlarged view of an alternative type of anchor barb; and

[0077] Fig.41 is with Fig.34 A perspective view of another heart valve stent similar to the heart valve stent in FIG. 1 but having radially extending arms of different lengths, and Fig.41A is an enlarged view of another type of anchor barb. DETAILED DESCRIPTION

[0078] Valve replacement in the mitral or tricuspid annulus is the primary focus of this application, but certain features of the delivery systems described herein may also be used for other valve implantation locations, so unless expressly limited, the claims should not be limited to mitral or tricuspid valve replacement. A replacement heart valve may be delivered to the patient's heart mitral annulus or other heart valve location in a variety of ways, such as by open surgery, minimally invasive surgery, and percutaneous or transcatheter delivery through the patient's vasculature. Exemplary transfemoral approaches can be found in U.S. Patents Nos. 10,004,599 and 10,813,757, the entire contents of which are hereby incorporated by reference. This application contemplates all techniques for valve delivery.

[0079] Figure 1A is a cross-sectional view of a human heart in the systolic phase. The right ventricle RV and the left ventricle LV are separated from the right atrium RA and the left atrium LA by the tricuspid valve TV and the mitral valve MV (i.e., the atrioventricular valves), respectively. In addition, the aortic valve AV separates the left ventricle LV from the ascending aorta (not labeled) and the pulmonary valve PV separates the right ventricle from the pulmonary artery (also not labeled). Each of these valves has flexible leaflets that extend inwardly through and across corresponding orifices that meet or "join" in the fluid flow to form a one-way fluid blocking surface. The right atrium RA receives deoxygenated blood from the venous system through the superior vena cava SVC and the inferior vena cava IVC, which enter the right atrium from above and the inferior vena cava IVC from below. The coronary sinus CS is a collection of veins that join together to form a large vessel that collects deoxygenated blood from the heart muscle (myocardium) and delivers it to the right atrium RA.

[0080] During the diastolic phase or relaxation of the heart, venous blood collected in the right atrium RA is pulled across the tricuspid valve TV by the expansion of the right ventricle RV, and similarly, oxygenated blood is pulled across the mitral valve MV by the expansion of the left ventricle LV. Figure 1A As seen, the heart muscle squeezes both the right ventricle RV and the left ventricle LV, which forces venous blood through the pulmonary valve PV and the pulmonary artery into the lungs and forces arterial blood through the aortic valve AV, the ascending aorta, and throughout the body. During this high pressure phase, the leaflets of the tricuspid valve TV and the mitral valve MV close to prevent blood from flowing back into the respective right atrium RA and left atrium LA.

[0081] Figure 1B and Figure 1A Same view, but showing a heart with an enlarged (dilated) left ventricle LV, commonly referred to as dilated cardiomyopathy (DCM). Such a condition tends to pull apart the leaflets of the mitral valve MV, preventing it from closing properly, often resulting in mitral regurgitation, manifested as a jet of blood escaping through the apparently closed MV. The regurgitation reduces the pressure generated in the left ventricle LV, and therefore reduces the pressure gradient across the aortic valve AV, which reduces the amount of blood pumped through the body.

[0082] In a similar way, Figure 1C is the same view of the heart showing right ventricle RV enlargement, a condition caused by various factors. The tricuspid valve TV annulus dilates outward toward the RV anterior and posterior free walls, which can lead to functional tricuspid regurgitation, as shown. The reduced pumping output to the lungs through the pulmonary valve PV reduces the overall efficiency of the oxygenation process, leading to a variety of cascading health problems.

[0083] The present application provides a number of solutions to the problems caused by dilated cardiomyopathy (DCM) or functional tricuspid regurgitation. Generally speaking, implanting a replacement expandable prosthetic heart valve within an enlarged annulus may result in a secondary problem of paravalvular leakage due to the widened annulus. First, commercial expandable prosthetic heart valves have a cylindrical exterior that does not closely match the non-circular peripheral shape of the mitral or tricuspid annulus. Second, the stent frame of the expandable prosthetic heart valve is either self-expanding or balloon-expandable. Although balloon-expandable stent frames apply more outward force to the annulus, both types of stent frames cannot avoid potential leakage around their exteriors.

[0084] The present application contemplates an expandable prosthetic heart valve that grasps the surrounding annular tissue and pulls it radially inward against the outside of the valve. This not only helps to reduce paravalvular leakage, but may also help remodel the annulus and subvalvular structures over time. For example, an expandable heart valve of the type described herein implanted in the tricuspid annulus pulls the annulus radially inward, which also pulls the adjacent wall of the right ventricle RV inward. It is believed that over time, the improved blood flow and radial contraction of the tricuspid annulus help remodel the right ventricle RV and reduce its expansion. Another potential benefit of the expandable heart valve described herein is the ability to minimize the device profile required to treat very large annuli. That is, instead of selecting an oversized heart valve, a valve of the appropriate size is used and then the annulus is pulled around the valve. In addition, the contractile heart valve described herein provides an adaptable valve platform in which a small number of valves of different sizes can be used to treat a wide range of annular sizes. The maximum size of current prosthetic heart valves is 19mm to 31mm or 33mm, with an increment of 2mm. The contractile heart valves disclosed herein can be provided in sizes of 19 mm for annuli between 19 mm and 21 mm, 23 mm for annuli between 23 mm and 25 mm, and so on, thereby reducing the inventory of valve sizes required. Finally, the various heart valves described herein can be implanted with the aid of fluoroscopy, as can current expandable heart valves.

[0085] Figure 2A is a partial cross-sectional view through the left side of the heart showing the mitral valve and annulus above the left ventricular structures, and Figure 2B is a plan view of the mitral valve showing the well-known nomenclature of the annulus and leaflets. The mitral valve MV primarily comprises a pair of coapted leaflets (anterior leaflet AL and posterior leaflet PL) secured around their outer edges to the fibrous mitral annulus MA. The inner edges of the anterior leaflet AL and posterior leaflet PL are connected to chord-like chordae tendineae CT extending downward into the left ventricle LV and are tied to the papillary muscles PM extending upward from the muscular myocardium M defining the left ventricular cavity. As the main outlet pumping chamber of the heart, the myocardium M contracts during the systolic phase, which reduces tension in the chordae tendineae CT and allows the leaflets AL, PL to come together or coapt.

[0086] like Figure 2BAs seen, the peripheral mitral valve annulus MA is generally described as D-shaped, with one side adjacent to the anterior leaflet AL being slightly straight and the side adjacent to the posterior leaflet PL being more rounded or convex. The leaflets are shaped so that the coaptation line resembles a smile that is generally parallel to the posterior side of the mitral valve annulus MA. Compared to the posterior leaflet PL, the anterior leaflet AL spans a smaller portion of the periphery surrounding the mitral valve annulus MA, but the anterior leaflet AL has a single cusp whose convex free edge extends further into the orifice defined by the mitral valve annulus MA. Typically, the anterior leaflet AL has three marked areas or cusps A1, A2, A3 around its periphery. On the other hand, the posterior leaflet PL is generally divided into three cusps P1, P2, P3 around its periphery by folds and has a generally concave free edge. Two commissures (the anterior commissure AC and the posterior commissure PC) generally define the intersection of the coaptation line between the two leaflets AL, PL and the mitral valve annulus MA. The tricuspid valve TV is not described in detail, but is generally described as an irregular oval shape. The tricuspid annulus has three dissimilar leaflets that extend inwardly for coaptation.

[0087] It should be understood that any of the heart valve stents disclosed herein can be shaped to conform to the following: Figure 2B That is, all stents are shown as having a tubular body that contains and supports the valve leaflets. The body can be D-shaped instead of FIG. 3A to FIG. 3B and Figure 4C The circular plan view is seen with the side adjacent to the anterior leaflet AL implanted being slightly straight, and the side adjacent to the posterior leaflet PL implanted being more rounded or convex.

[0088] Several of the contraction heart valve embodiments described herein are shown to be implanted in the mitral valve MV, but it should be understood that the same valve can also be used at the tricuspid valve TV. In fact, all of the heart valve embodiments described herein can be used interchangeably at any of the atrioventricular valves.

[0089] Figure 3A is after implantation of the expandable prosthetic heart valve 20 of the present application but before the final step of deployment Figure 2A A similar partial cross-sectional view of the mitral valve annulus MA and the left ventricle LV. A similar partial cross-sectional view of the mitral valve annulus MA and the left ventricle LV. Figure 3B is the same view after the final step of radially contracting the outer skirt anchored to the mitral annulus. FIG. 4A to FIG. 4C , which shows an exemplary valve stent without a fabric covering and valve leaflets.

[0090] The prosthetic heart valve 20 includes an inner expandable valve member 22 that supports flexible leaflets 24 therein. Typically, there are three leaflets 24 having peripheral cusp edges sutured to the surrounding structure with the free edges engaging one another in a flow orifice through the valve member 22. Because this is a replacement mitral valve, the sutured cusp edges 25 of the leaflets 24 are shown, with blood only being allowed to flow downward from the left atrium to the left ventricle LV through the valve member 22. A similar arrangement is envisioned for the same prosthetic heart valve 20 implanted at the tricuspid annulus TA with blood flow unidirectionally downward into the right ventricle RV.

[0091] A peripheral skirt 26 circumferentially surrounds the inner valve component 22, and a contraction suture 27 extends around the top edge of the skirt. The valve component 22 and skirt 26 include a fabric covering 28 sutured to a structural stent frame 30. The upper edge of the inner valve component 22 has a plurality of evenly spaced eyelets 32 formed by the stent frame 30. The eyelets 32 can be used to facilitate delivery of the expandable valve 20. For example, sutures or wires can be passed through the eyelets 32 to control advancement and radial expansion / contraction of the valve.

[0092] Reference now FIG. 4A to FIG. 4C , the stent frame 30 includes a generally tubular inner portion 34 that defines the shape of the inner valve member 22. The eyelet 32 ​​is shown at the top of a plurality of converging struts 36 that define the inner portion 34. In the illustrated embodiment, the struts 36 are formed in a generally serpentine pattern in the axial direction and are fixed to each other at the nodes to form a unit or opening therebetween. The structure can be contracted to a minimum for delivery and then expanded into the shape shown. It should be understood that the specific configuration of the struts 36 can be modified as known in the art. For example, another common pattern of the struts 36 defines a series of connected diamond shapes that form units of similar shapes therebetween.

[0093] The plurality of outer arms 38 include a generally arcuate post 40 joined to the tubular inner portion 34 at a lower bend 42. Each of the arms 38 has one or more outwardly projecting barbs for anchoring into the surrounding tissue. In the illustrated embodiment, there are three barbs 44a, 44b, 44c extending outwardly from each of the posts 40. The first barb 44a is angled downwardly, while the other two barbs 44b, 44c are angled upwardly. Although the entire stent frame 30 will be covered with a biocompatible fabric, the barbs 44a, 44b, 44c protrude outwardly through the biocompatible fabric so that when the prosthetic valve 20 is expanded, the barbs are embedded in the surrounding annular tissue. As will be described below, a variety of different types of barbs are contemplated and are generally interchangeable. The cloth-covered arms 38 define the peripheral skirt 26.

[0094] In the illustrated embodiment, Figure 4C A top view of the floor plan and Figure 5 As can be seen from the flat view of the 3D image, there are 12 outer arms 38 evenly spaced around the tubular inner portion 34. A 180° bend 42 connects each of the arms 38 to a pair of converging struts 36 at the lower end of the inner portion 34. The serpentine struts 36 extend upwardly and connect with two adjacent struts, thereby ultimately converging with one of the adjacent struts to define an eyelet 32. Thus, there are 12 eyelets 32. Of course, the number of outer arms 38 and the strut configuration of the tubular inner portion 34 can vary, with a practical minimum of 6 and a practical maximum of 18.

[0095] The material of the stent frame 30 enables it to be compressed down to a low profile for passing through a delivery tube or access tube, while also being able to expand to a shape as shown, which can be as large as 33 mm in diameter for the tubular inner portion 34. For a self-expanding stent frame 30, the material is desirably a superelastic metal such as Nitinol. For a balloon expandable stent frame 30, the material is desirably a stainless steel or cobalt-chromium alloy such as Elgiloy. The struts 36 and posts 40 are shown as having a square or rectangular cross-section, reflecting the common manufacturing technique of laser cutting the stent frame from an initial tubular blank. Of course, round wire may alternatively be used to form the stent frame 30.

[0096] Return to reference Figure 3A and Figure 3B as well as FIG. 6A to FIG. 6C , implantation and deployment of the prosthetic heart valve 20 will be described. FIG. 6A to FIG. 6C is a sequential view showing the self-expanding valve stent 30 being discharged from the access tube 50 to illustrate its deployment steps. The valve stent 30 is shown without a cloth covering and without any valve leaflets or other soft structures. The valve stent 30 defines the shape of the entire heart valve 20, therefore. Initially, the pusher 52 pushes the valve stent 30 (i.e., the heart valve 20) from the distal end of the access tube 50. The posts 40 defining the arms 38 are initially held by the access tube 50 in a linear, distally facing orientation. When the arms 40 emerge from within the access tube 50, the arms curl 180° in the proximal direction due to their inherent spring bias. Once again, the self-expanding stent frame 30 is desirably formed of nitinol, which can be easily shaped to assume a final configuration.

[0097] As pusher two continues to expel the valve stent 30, the tubular inner portion 34 is eventually released and expands to its final diameter. Figure 6CThe valve support 30 is shown expanded to its maximum diameter. The outer arms 38 forming the fabric-covered peripheral skirt 26 first contact the natural valve leaflets, and the barbs 44 embed themselves in the tissue. The tether or wire 54 is shown extending from the valve support 30 back into the access tube 50. Such tethers or wires can be used to manipulate the valve to a third position. For example, the wire can be passed through the eyelet 32 ​​at the proximal end of the tubular inner portion 34 and initially kept taut, thereby preventing the tubular inner portion from expanding once it is discharged from the tube 50. Then, the tether or wire 54 can be slowly released to allow expansion of the inner portion 34. Conversely, if the positioning of the heart valve 20 is incorrect, the tether or wire 54 can be retracted into the access tube 50 to contract the valve support 32, thereby allowing the position to be adjusted.

[0098] Now return to reference Figure 3B , the peripheral skirt 26 is shown as being radially contracted. This can be achieved by extending a contracting suture or band 27 around the top edge of the skirt 26. For example, a tunnel or pocket of fabric can be formed around the periphery of the top edge of the skirt 26, through which the suture or band 27 is passed. By pulling the band 27, the top edge of the skirt 26 is pulled inwardly closer to the inner valve component 22. By means of the barbs 44, the surrounding tissue including the valve ring and leaflets is also pulled inwardly.

[0099] The process of tightening the surrounding tissue in this manner can be completed after closing the access incision and under fluoroscopy. The suture or band 27 can be extended outside the body through the sealed incision (i.e., with a purse-string suture), typically through an elongated flexible tubular sheath (not shown). The contraction suture or band 27 is an example of an external actuator that can be used to reduce the overall diameter of the heart valve 20 after implantation, which simultaneously pulls the annulus inwardly due to the anchoring barbs 44. It will become apparent that such an external contraction mechanism is in contrast to the intrinsic contraction mechanism disclosed elsewhere herein.

[0100] Reference now Figure 7 , shows an alternative expandable prosthetic heart valve 60 of the present application, which has a generally cylindrical valve member 62 with an upper peripheral flange 64. The valve member 62 and the peripheral flange 64 can be defined by a valve stent 66 covered with a biocompatible fabric 68. In the illustrated embodiment, the valve stent 66 has a plurality of connecting struts to define the cylindrical valve member 62 and radial arms extending outward at the proximal end of the valve member to define the peripheral flange 64. As described elsewhere, the valve stent 66 can be formed by a single self-expanding nitinol stent, or can be balloon expandable as desired. As previously described, the flexible leaflets 70 are sutured to the interior of the valve member 62 and define a one-way flow blocking surface. To reiterate, the prosthetic heart valve 60 is constructed to be implanted at one of the atrioventricular valves.

[0101] A plurality of individual valve anchors 72 are shown as being broken down above the prosthetic heart valve 60 before being deployed through the peripheral flange 64. In this case, the valve anchors 72 are not integrated into the heart valve 60, but are deployed separately to eventually form part of a fixed implant. In the illustrated embodiment, each of the anchors 72 has an upper head 73 and a lower helical tissue anchor 74. It should be understood that the specific configuration of the tissue anchor 74 may not be helical, such as straight or curved barbs, etc. A lasso or band 76 is passed through the head 73 of each of the anchors 72. The free end 78 of the band preferably extends proximally outside the body after passing through one of the anchors 72. Pulling the free end 78 reduces the circumference of the band 76.

[0102] Fig. 8A is a cross-sectional view through the left ventricle showing the final steps of deployment within the mitral annulus prior to deployment Figure 7 60. The valve support 66 has been expanded so that the valve member 62 is in contact with the leaflets of the mitral valve. The anchors 72 have been deployed around the peripheral support 64 so that they are embedded in the mitral valve annulus MA. The free end 78 of the band 76 is usually passed out of the body through a tubular sheath (not shown). Figure 8B The same view after the final step of radially contracting the peripheral flange 64 anchored to the mitral valve annulus MA by pulling the free end 78 of the band 76. This pulls the anchor 72 inwardly, which in turn pulls the surrounding tissue leaflets and annulus into better contact with the exterior of the valve member 62. Again, for greater clarity, Fig. 8A and Figure 8B Only the valve support 66 is shown, but it should be understood that the fabric covering 68 and leaflets are part of the finished valve 60. Here again, the band 76 acts as an extrinsic contraction mechanism that is actuated from outside the body or at least is not intrinsic to or carried by the heart valve itself.

[0103] Fig.9A The valve portion 82 and the upper peripheral flange 84 are Figure 7 The valve shown is similar to a perspective view of a further expandable prosthetic heart valve 80. The valve 80 may again be formed from a structural valve support 86 covered with a fabric 88.

[0104] A plurality of anchors 90 are shown deployed around the peripheral stent 84. The anchors 90 may be as described above, such that only the head is shown with a corkscrew or other tissue piercing member (not shown) inserted through the flange 84 into the annular tissue. Two of the anchors 92 are radially spaced apart from one another at locations around the peripheral stent 84, and each anchor has a tether 94 extending therethrough. The tether 94 passes through the anchors 92 and extends circumferentially through the peripheral flange 84 or extends over the top of the peripheral flange to connect to a free edge 96 of the peripheral flange. The peripheral flange 84 is discontinuous at the free edge 96 so that it has a variable circumferential profile. Fig. 9B The final step of circumferentially tightening peripheral flange 84 to cause its radial contraction is shown by pulling tethers 94. Free edge 96 is pulled toward anchor 92, which tightens peripheral flange 84. By virtue of the reduction in the circumferential perimeter of flange 84, surrounding tissue is pulled inwardly toward valve member 82.

[0105] Fig. 10A 1 is a front view of an alternative heart valve stent 100 having a tubular valve portion 102 and an upper peripheral flange 104 with anchoring barbs 106. As seen, anchoring barbs 106 extending radially outward from the valve portion 102 may also be provided. In this embodiment, the pillars of the valve stent 100 are formed into a diamond shape, wherein the barbs 106 are defined by sharp points. As seen elsewhere in this application, the stent 100 is shown without an outer fabric covering and valve leaflets. The assembled heart valve may be formed by a single expandable superelastic stent 100 covered with fabric, and the flexible valve leaflets are supported in the valve portion 102 to enable one-way blood to pass through the valve (downward for the mitral valve).

[0106] Fig. 10B One example of an anchoring barb 106 is shown. The barb 106 may include a shaft extending perpendicularly or at an angle from a particular body structure (flange, body, etc.) with a small hook 107 or other such device near the end to help prevent the barb from being pulled out of the tissue. There may be multiple such hooks 107.

[0107] Fig. 10CA similar valve stent 100' is shown, which includes a body 102' and an upper peripheral flange 104' extending radially outward from an upper end 105' of the body 102'. In this embodiment, the upper peripheral flange 104' extends substantially perpendicular to the stent opening defined by the upper end 105'. A ventricular anchor 106' is curled downward from a lower end 108' of the stent body 102' and then curled back upward approximately 180°. The ventricular anchor 106' is shaped to capture the native valve leaflets between the ventricular anchor and the body 102' of the stent. In combination with or in lieu of the retraction barbs on the upper peripheral flange 104', the ventricular anchor 106' may be constructed to retract after implantation, such as by providing a band around its periphery, such as in Figure 7 To the embodiment of Fig. 8. The disc-shaped upper peripheral flange 104' can be positioned flat across the top surface of the mitral annulus MA and provide increased surface area contact for tissue ingrowth.

[0108] The body 102' may have an outwardly facing barb 106, Fig. 10A In addition, inwardly directed barbs 106a may be provided along each of the ventricular anchors 106', wherein the barbs are aligned with the reference Fig. 10B The barbs are similar to those shown and described.

[0109] Fig. 10D A valve stent 100' is shown implanted at the mitral valve annulus MA. Ventricular anchors 106' are deployed to the outside of the mitral valve leaflets and are configured to collapse inwardly, as shown. This helps to secure the valve with stent 100' within the annulus.

[0110] Fig.11A and Fig. 11B is an example of Fig. 10A Two views of deployment steps of a valve stent 100" similar to the valve stent in FIG, wherein expansion of the central valve portion 102" causes radial contraction of the upper peripheral flange 104". That is, radial expansion of the valve portion 102" causes circumferential expansion of the petal-like struts 108a of the peripheral flange 104" (as seen at 108b), which causes their outer ends to radially contract from an initial diameter seen at 109. Because the barbs on the struts 108a are embedded in the surrounding annular tissue, this pulls the tissue toward the valve. This is an example of an intrinsic contraction mechanism because radial contraction of the valve and surrounding annulus is caused by structure carried by or intrinsic to the heart valve, rather than requiring an external contractor.

[0111] FIG. 12A to FIG. 12C1 is a sequence view showing further valve stent 110 being ejected from access tube 112 to illustrate the deployment steps thereof. As previously described, pusher 114 may be used to advance valve stent 110 from within tube 112, possibly in combination with retraction of the tube, such as Fig. 12B Initially, the tubular valve portion 160 is retained within the access tube 112 while the peripheral flange 118 is radially expanded to a first diameter D 1 Upon further exiting from the tube 112, the peripheral flange 118 rolls back on the entry tube 112 and in the process the radially outer end contracts inwardly to a value less than D 1 The second diameter D 2 10, the ends of the peripheral flange 118 have barbs that embed into the annular tissue so that this reduction in diameter pulls the tissue inward around the sequentially expanded valve portion 116. Again, this is an intrinsic contraction mechanism because the radial force is generated by the change in shape of the valve support 110 itself.

[0112] Fig.13A and Fig. 13B 1 are top plan and side views of an exemplary expandable prosthetic heart valve 120 defining a tubular valve portion 122 having a peripheral stent 124. As described elsewhere, valve 120 may be defined by an expandable valve stent 126 covered with fabric 127 via a plurality of connecting sutures or stitches 128. Fig.13A The radial arms 130 of the valve support 126 are shown extending outwardly from the inlet (proximal) end of the valve portion 122 and defining the peripheral flange 124 together with the fabric skirt 131. One or more tissue anchors 132 can be fixed to each radial arm 130, or the outer end can be reinforced to receive a separately deployed anchor, such as the above referenced Figure 7 130 ; however, anchors may be included along the length of each arm 130, such as illustrated by anchor 133 in one arm. Anchors 132, 133 may be as described elsewhere in this application. This particular configuration of the heart valve 120 may be viewed as a model for many of the embodiments described herein, wherein the fabric-covered peripheral flange at the proximal end of the fabric-covered valve member provides tissue contraction structures in the form of various contraction arms connected by fabric. Although the flange is illustrated as having a particular shape, it should be understood that the flange may have different shapes and preferably conforms to the shape of the surrounding tissue, such as along the top of the annulus.

[0113] Fig. 13C yes Fig.13A1, showing details of a particular embodiment of the peripheral flange 124 and the retraction arm 130. Each of the arms 130 includes a series of elongated diamond-shaped struts 134 connected in series and extending from the inner valve portion 122 to each anchor 132. The diamond-shaped struts 134 form an extension spring that is biased to a retracted length and maintained extended. That is, a filament or suture 135 is coiled along and through the diamond-shaped struts 134. The struts 134 are held in tension by the sutures 135 so that when the heart valve 120 is implanted at the annulus using the anchors 132, the struts expand radially.

[0114] Fig.13D 1 is an enlarged portion thereof, showing the contraction mechanism in each arm 130. That is, the suture 135 is biodegradable in the body after a period of time. The upper portion shows the dissolved suture 135, while some of the suture remains close to the inner valve portion 122. The struts 136 in the portion without the coiled suture 135 have collapsed, so that the diamond-shaped opening is now much smaller due to the elasticity of the struts. The inward radial arrows indicate the overall contraction of the arm 130, which pulls the anchor 132 inward, thereby tightening the surrounding annular tissue toward the inner valve portion 122. The degradation rate of the suture 135 can be adjusted so that the inward tightening occurs quickly (such as within a few days) to more slowly (such as within a month or two months), depending on the needs. Here, we see a slightly different intrinsic contraction mechanism again, in which the radial force is generated by the disintegration of the suture 135 and the reduction in the length of the contraction arm 130.

[0115] Fig.14 1 is a top plan view of an upper peripheral flange of an exemplary valve support 150 of the present application, which is defined by a plurality of radial arms 152 having anchors 154 on their outer ends. Fig.14A and Fig. 14BAs best seen in , actuation of one radial arm before and after radial contraction includes removing the reinforcing wire or member 156, causing the arm 152 to collapse. More specifically, the arm 152 is desirably shape-set into a radially contracted shape and maintained in its linear configuration by the reinforcing member 156. The shape-set arm 152 forms an extension spring that is biased to a contracted length and maintained extended by the reinforcing member 156. The reinforcing member 156 can be a generally flexible wire having sufficient column stiffness to resist collapse of the arm 152. The reinforcing member 156 desirably extends along the arm 152 and passes through a hole formed in the anchor 154. Each of the reinforcing members 156 releases each of the arms 152 to collapse. It should be understood that the valve is first expanded and the anchor 154 is embedded in the tissue before all of the reinforcing members 156 are pulled out, at which time the arm 152 and the peripheral flange defined thereby collapse radially. This is a hybrid form of the contraction mechanism that requires the removal of an external element, namely the reinforcing member 156, but then generates radial contraction by a reduction in the length of the radial arms 152 that are intrinsic to the heart valve. Thus, the hybrid contraction mechanism requires an external "trigger" action, but the source of the contraction force is part of the heart valve or is carried by the heart valve and remains implanted. In contrast, if the radial arms 152 were constructed to be bioresorbable, the contraction mechanism would be entirely intrinsic to the heart valve.

[0116] Fig. 14C Another internal example of the same contraction mechanism is shown, where the reinforcing member 156' is a rod or bar carried by the stent 150 and is configured to dissolve after a period of time. For example, the reinforcing member 156' may be resorbed within a few minutes after exposure to blood, which provides sufficient time to firmly embed the tissue anchor before the radial arms 152 collapse and the flanges pull the surrounding tissue inward.

[0117] Fig.15A is similar in structure to Fig.13A A top plan view of an exemplary prosthetic heart valve 160 having a central valve component 162 and a peripheral flange 164. The inner stent frame has a Fig.14 That is, flange 164 has arms 166 that terminate in outer anchors 168. Arms 166 are radially collapsible, and anchors 168 have barbs or may be secured to the annular tissue with separate anchors. When desired, arms 166 may be provided as Fig. 15B As shown, the arms 166 collapse, thereby causing the peripheral flange 164 to contract radially. The anchors 168 pull the surrounding tissue inward against the central tubular valve member 162, thereby ensuring a tighter fit. As described herein, arms 166 such as shown can be configured to collapse in a variety of ways, and similarly, Fig.15AThe fabric covered valve structure shown can be adapted in a variety of ways. The radial arms 166 can provide an intrinsic retraction mechanism, or can be a hybrid extrinsic / intrinsic type if external release wires or sutures are used.

[0118] For the fully intrinsic example, Fig.16A and Fig. 16B 1 is a top plan view of another exemplary valve stent 170 having a central valve portion 172 and a radially contracting peripheral flange with a series of outer petals 174. Anchor members or eyelets 176 are provided on the outer ends of the petals 174 as shown, and the stent structure is covered with fabric as explained herein. After expansion at the implantation site, as shown in FIG. Fig.16A As shown, the peripheral flange has a diameter D defined by a circle of revolution 178 of the anchor 176. 1 The barbs on the anchor 176 or separate barbs passing through the anchor 176 are then deployed into the annular tissue. Fig. 16B The valve support 170 is shown after radial contraction. The flap 174 is preferably superelastic and expands circumferentially when the central valve portion 172 expands radially. This contracts the outer end of the flap 174 to have a diameter D 2 circle of rotation, thereby pulling the surrounding tissue inward.

[0119] Fig.17A and Fig. 17B 1 is a top plan view of another exemplary valve stent 180 having a central valve portion 182 and a radially contracting peripheral flange defined by a series of helically arranged arms 184. The stent 180 may also have an outer expansion and a flange positioned to surround the valve leaflets. Fig. 10C The ventricular anchor 106' is shown with two or more ventricular anchors or arms 183 that are very similar to the ventricular anchor 106'. The arms 183 are curled downward from the lower or outflow end of the stent body and then curled back upward about 180 degrees. Similarly, the outer ends of the arms 184 have anchors or eyelets 186 that define a diameter D when expanded together. 1 After the valve expands and secures the anchor or eyelet 186 to the surrounding tissue, the central valve portion 182 rotates about its own axis to pull the anchor or eyelet 186 inward. That is, as the valve portion 182 rotates, the inner end of the arm 184 pulls the outer end to the contracted diameter D 2 The rotation of the valve portion 182 must be initiated from the outside, but the radial contraction of the heart valve is generated by an intrinsic mechanism. Thus, this is a hybrid form of contraction mechanism.

[0120] In a slightly different configuration, 18A to 18C1 is a schematic elevational view of a two-part expandable prosthetic heart valve stent assembly 190 showing several steps of its deployment. Assembly 190 includes an inner cylindrical valve member 192 that eventually expands outward into contact with a surrounding anchoring stent 194. Stent 194 has a plurality of struts 196 with radial arms 198 embedded therein. Although not shown, arms 198 each have a barb at their distal end.

[0121] Initially, the anchoring stent 194 is advanced through the access tube into an implantation position within one of the atrioventricular valves. Expansion of the anchoring stent 194 is accomplished while the radial arms 198 are embedded in the surrounding tissue. The inner valve component 192 is positioned within the anchoring stent 194 but remains unexpanded. Subsequently, as Fig.18B As indicated, the anchor stent 194 is rotated about its axis, causing the struts 196 connected at the lower end of the anchor stent to rotate into a spiral shape. Because the outer arms 198 are anchored to the tissue, this tends to pull the tissue inward. Finally, the inner valve member 192 expands, as shown in FIG. Fig.18C Because the anchoring stent 194 has been pulled into the surrounding tissue, the fit of the valve component 192 is improved. Again, this is a hybrid contraction mechanism that requires external input to rotate the anchoring stent 194, but the final radial contraction is generated by an intrinsic mechanism built into the heart valve.

[0122] Fig.19 2 is a front view of another valve stent 200 having a central valve portion 201 with an upper eyelet 202. Radially retractable arms 203 distributed around the upper periphery and passing through the eyelet 202 form a peripheral flange. Although only two arms 203 are shown, the stent 200 may have 6 or up to 18 such arms. Each arm 203 is connected to an external actuation tether 204, which is configured to pull the arm radially inward, and the barbs 206 on the outer ends of the arms are embedded in the annular tissue. Fig.19A The use of a ratchet mechanism 208 to retract one of the arms inwardly to prevent outward movement is illustrated. The tethers 204 can be pulled simultaneously to contract the peripheral flange formed by the gathering arms 203, thereby contracting the annulus around the central valve portion 201.

[0123] Fig. 20A and Fig. 20B 2 are perspective views of an outer fabric structure 210 that can be used to collapse an expandable prosthetic heart valve in both an initial deployed configuration and a collapsed configuration, respectively. The fabric structure 210 includes a generally tubular outer wall 212 having an upper flexible skirt 214 secured thereto by sutures 216. Although not shown, the fabric structure 210 may include an inner superelastic skeleton that defines its overall cylindrical shape but is susceptible to collapse both upon delivery and subsequently during collapse of the structure.

[0124] The outer wall 212 has a series of axial or vertical struts 220 on its exterior, each of which has one or more outwardly projecting barbs 222. The struts 220 span an annular horizontal joint in the wall 212 that forms a circular recess 224 for a pair of flexible tightening elements 226. The tightening elements 226 pass through a tubular sheath 228 and diverge around the circular length of the wall 212 before entering the recess 224. Thus, pulling the tightening elements 226 from an external position enables the tubular wall 212 to contract, as shown in FIG. Fig. 20B What I see.

[0125] Fig.21 A prosthetic heart valve 230 is installed therein. Fig. 20A 210. The heart valve 230 may be similar to those described above, with the flexible leaflets 232 sewn within a tubular fabric covered valve support 234. The inner circular orifice of the flexible skirt 214 may be secured to the top edge of the heart valve 230 via sutures 236.

[0126] Fig.22A and Fig. 22B yes Fig.21 210 before and after radial contraction of the outer fabric structure 210. More specifically, after the assembly is delivered into position within the target annulus, both the fabric structure 210 and the heart valve 230 are expanded. Thus, the barbs on the outer wall 212 of the fabric structure 210 engage the annular tissue. Before or after closing the surgical site, the tightening element 226 is pulled to reduce the size of the fabric structure 210, such as Fig. 22B This pulls the surrounding annulus inwardly toward the cylindrical heart valve 230, thereby improving the contact between the surrounding annulus and the cylindrical heart valve. This is another extrinsic contraction mechanism.

[0127] Fig.23A 2 is a front view of another valve support 240 having a tubular valve portion 242 and a plurality of outer radially retractable arms 244. Each of the arms 244 is coupled to and cantilevered from the lower end of the valve portion 242 and has a barb 246 on the distal end of the arm. Fig. 23B , depicting a retraction mechanism for each of the arms 244. That is, each arm 244 is secured to an axial post 248 secured at the lower end of the valve portion 242 by, for example, a bracket 250. A collar 252 is arranged to travel vertically upward along the post 248 when pulled by an external tether 254. The collar 252 is constrained to move upward by a series of ratchet teeth 256 disposed on the axial post 248.

[0128] Fig.23C and Fig.23D2 is a schematic diagram illustrating the operation of retracting arms 244. Specifically, pulling upward on outer tether 254 lifts collar 252 along each of posts 248. Because arms 244 are biased in a gentle outward arc, collar 252 cams each of the arms radially inward. Separation occurs after the heart valve is expanded within the annulus, allowing barbs 246 on each of arms 244 to engage surrounding tissue. Under fluoroscopy, the desired amount of retraction of the surrounding tissue can be determined. Again, this enhances engagement between the surrounding tissue and the prosthetic heart valve.

[0129] Fig.24 2 is a front view of yet another valve support 260 having a central tubular valve portion 262 connected to a plurality of outer (generally axially oriented) arms 264 via a lower U-shaped bend 266. Each of the arms 264 has an outer barb 268 thereon and is slightly biased inwardly toward the valve portion 262. That is, each of the arms 264 has an inward bias that creates a slightly inward angle θ relative to the vertical. The angle θ may be between 5-20°.

[0130] Fig.25A and Fig.25B 2 is a view of one of the arms 264 of the valve support 260 before and after the temporary measures holding the arm outward are removed. More specifically, each of the arms 264 initially has a reinforcing tube 270 mounted thereon, preferably at the lower U-shaped bend 266. The reinforcing tube 270 has a larger radius of curvature than the U-shaped bend 266 to force the arm 264 into a more vertical orientation. Each of the tubes 270 is bioresorbable after a period of time in the body, and then, as Fig.25B As can be seen, the arms 264 return to their initial inward angles. In one embodiment, the reinforcing tube 270 returns to its original shape after a period of one week to one month in the body, which serves to pull the surrounding tissue inwardly by means of the engagement of the barbs 268. This is completely intrinsic to the heart valve.

[0131] Fig.26A and Fig.26B 2 is a view of one of the arms 264 before and after another temporary measure to hold the arm outward is removed. In this form, a plurality of fixed reinforcement plugs 272 are initially positioned within a recess 274 on the inside of the arm 264. The reinforcement plugs 272 are also bioresorbable so that after they dissolve, the arm 264 is once again biased inwardly to a relaxed orientation. Those skilled in the art will appreciate that there are various ways to produce such a delayed inward movement of the arm 264.

[0132] Fig. 272 is a front view of yet another valve stent 280 having an inner tubular valve portion 282 connected to a plurality of axially oriented outer arms 284 by a lower U-shaped bend 286. Each of the arms 284 has an active tissue anchor 288 at its distal end. By "active" tissue anchor in this sense is meant a tissue anchor that can be manipulated to grasp tissue, as with a barbed type anchor, simply pressed against the tissue to engage.

[0133] Fig.27A FIG. 2 is an enlarged view of one of the active tissue anchors 288 that is primarily comprised of a generally rectangular frame 290 having relatively protruding levers 292 at each end. The rectangular frame 290 defines a central opening into which a plurality of teeth 294 protrude. The tissue anchor 288 may be made of a superelastic material and have a flat relaxed configuration, such as Fig.28C As seen from the top view.

[0134] It should be noted that the orientation of the clamping anchor 288 can be different with the hinge / flex levers 292 on the top and bottom, where the teeth 294 are oriented inward from the left and right sides as shown, or perpendicular with the hinge / flex levers 292 on the left and right sides, and the teeth 294 are oriented inward from the top and bottom sides. In addition, the location where either of the levers 292 is attached to the frame can be relocated to a low strain area so as to not interfere with the hinge / flex side of the anchor 288. That is, instead of positioning the lower hinge / flex lever 292 at the connection with the U-bend 286, the anchor 288 can be oriented horizontally to decouple the flexing of the lever from the flexing of the U-bend 286.

[0135] FIG. 28A to FIG. 28C 2 is a top plan view of one of the active tissue anchors 288, showing several stages of deployment. Initially, the external tensioning member 296 is used to hold the tissue anchor 288 in a tensioned configuration, such as Fig.28A That is, the tensioning member 296 comprises a flexible filament or suture thread that passes through an orifice in each of the outwardly protruding levers 292. By pulling the levers 292 using the outer sheath 298, the frame 290 bends itself backwards, causing the teeth 294 to protrude radially outward. Once the heart valve is introduced into the annulus and expanded, the outwardly protruding teeth 294 pierce the surrounding tissue. Subsequently, the tensioning member 296 is relaxed, as shown in FIG. Fig.28B As can be seen, this allows the frame 292 to both spring back toward its flat, relaxed configuration, which in turn causes the teeth 294 to pivot inwardly toward each other. This action causes the tissue to be firmly grasped between the jaws, much like a bear trap.

[0136] For example, active tissue anchors 288 can be used in place of barbs with any of the various valve stent embodiments described herein. After grasping tissue with active tissue anchors 288, a tightening mechanism is deployed to pull the tissue inward toward the central valve portion 282. The tightening mechanism can be any of the tightening mechanisms described herein.

[0137] The present application presents a plurality of expandable prosthetic heart valves, which are constructed to contract the target annulus at the time of implantation or after implantation to enhance engagement with the target annulus. A plurality of embodiments envision that once the valve is implanted, the components of the heart valve are manipulated from outside the body. The technology involves winding sutures or other such control elements from the target annulus through a sealing incision to the outside of the body. In the same manner, a guide suture pre-installed around the target annulus can be used to control and / or manipulate the heart valve when the heart valve is advanced to the annulus. An additional technique used in conjunction with a surgical heart valve implanted in open heart surgery more commonly involves pre-installing tissue anchors around the annulus, and then landing the expandable heart valve along an array of sutures connected to the tissue anchors. By placing tissue anchors around the outside of the annulus, and then advancing a smaller size heart valve downward along an array of sutures, the annulus can be contracted while the heart valve is being delivered, without any further manipulation.

[0138] For example, Fig.29 is a partial cross-sectional view through the left side of the heart showing the mitral valve and annulus with a pre-installed tissue anchor 320 therein. An expanded prosthetic heart valve 322 is shown being advanced down the annulus along an array of guide sutures 324. The heart valve 322 is shown having a configuration very similar to several of the configurations described above, with an inner generally tubular valve portion 330 and a peripheral flange 332 extending radially outward from its proximal end. As previously described, the valve portion 330 and the peripheral flange 332 are desirably formed from a single expandable superelastic stent 334 covered with fabric 336. Flexible valve leaflets 338 are supported within the valve portion 330 to enable one-way blood flow through the valve 322 (downward for the mitral valve).

[0139] Although not shown, the heart valve 322 is to be implanted on a beating heart and is therefore first delivered via an access tube or sheath in a collapsed configuration to a location adjacent to the target annulus. For example, the heart valve 322 is delivered collapsed through a tube to the left atrium above the mitral annulus and then ejected from the tube to expand to its larger shape, such as Fig.29 In the same manner, a tricuspid heart valve 322 will be delivered to the right atrium above the tricuspid annulus and expanded. A guide suture 324 is passed through the peripheral flange 332 of the valve 322 and desirably pre-installed and delivered with the valve, with the free end remaining outside the body for manipulation.

[0140] The tissue anchors 320 can take a variety of forms, including those having a helical lower anchoring portion attached to an upper head. Each anchor 320 has a small ring or hook 340 thereon through which a guide suture 324 is looped. That is, each of the tissue anchors 320 is remotely implanted with a loop of the guide suture 324 either pre-attached or subsequently passed through the hook 340. The tissue anchors 320 are spaced around the annulus so as to define a circumference that is greater than the outer circumference of the peripheral flange 332 of the heart valve 322. As the heart valve 322 is advanced downwardly along the array of sutures 324, the difference in diameter between the peripheral flange 332 and the circumference described by the tissue anchors 320 causes an inward contraction of the annulus, as shown in FIG. Fig.30 Seen. Fig.29 In the embodiment, only four coupled tissue anchors 320 and guide sutures 324 are shown evenly spaced at 90° around the annulus. However, eight or more anchors 320 and sutures 324 (most preferably 12, spaced 30° circumferentially) may be used to achieve a more uniform contraction of the annulus.

[0141] Each pair of lengths of guide suture 324 passes through the peripheral flange 332 before being looped through the hook 340 of one of the tissue anchors 320. The guide suture 324 can pass through a suture clip 342 attached to the peripheral flange 332, as will be described in more detail below. Alternatively, the guide suture 324 can pass through a reinforced area of ​​the peripheral flange 332 and then be used to secure the peripheral flange to the corresponding tissue anchor 320 by tying a knot or the like. For example, the heart valve 322 can be advanced downward until the peripheral flange 332 contacts the target annulus, wherein the tissue anchor 320 is pulled inward and located below the flange. As known, a knot pusher can then be used to secure the paired lengths of guide suture 324 on the top side of the peripheral flange 332. However, to facilitate the implantation process, the suture clip 342 is preferably incorporated into the peripheral flange 332.

[0142] Fig.30The prosthetic heart valve 322 is shown advanced almost down to the annulus, causing the pre-installed tissue anchor 320 to be pulled radially inward. At a certain point, the position of the heart valve 322 within the annulus enables the valve leaflets 338 to begin to operate and take over the task of regulating blood flow through the annulus from the natural leaflets. At this point, the surgeon can use fluoroscopy, echocardiography or other such visualization techniques to assess the effectiveness of the newly implanted heart valve. The degree of contraction of the surrounding annulus can vary, so that the tissue anchor 320 can maintain a certain degree of separation from the peripheral flange 332, or completely tighten against the peripheral flange to achieve maximum contraction, which can also be seen using fluoroscopy, etc. For example, the tissue anchor 320 can be radiopaque, wherein the radiopaque element is also sutured into the peripheral flange 332 to compare relative sizes. As mentioned above, the suture clip 342 can be used to fix the guide suture 324 at different stages of annular contraction. However, as described below, the suture clip 342 can also be used to connect directly to the tissue anchor 320.

[0143] For the retraction mechanism, refer to Figure 29 to Figure 30 The described system can be operated as an extrinsic mechanism or an intrinsic mechanism. That is, if the guide suture 324 remains connected after the valve becomes functional, and while the surgeon assesses the efficacy of the valve implant, further tensioning or loosening of the suture 324 is clearly an external actuator, and the system is extrinsic. However, if the valve is simply dropped down into position and the guide suture 324 is cut and tied, the resulting annular retraction is accomplished using a structure carried by or coupled to the heart valve, which is intrinsic to the heart valve.

[0144] Fig.31A and Fig.31B Engagement between a flat suture clip 342 on the peripheral flange 332 of the heart valve 322 and one of the tissue anchors 320 is shown. Pulling the guide suture 324 ultimately causes the hook 340 on the tissue anchor 320 to be pulled upward through the aperture 344 on the suture clip 342. One strand of each guide suture 324 can then simply be pulled out to disengage the hook 340 of the anchor 320 and removed from the body.

[0145] The clip 342 may be formed of a superelastic or other elastic metal material so that the aperture 344 flexes upward to allow one-way passage of the guide suture 324 and the hook 340, but elastically closes to clamp the guide suture 324 or the hook 340 and prevent reverse movement. A particular suture clip 342 is a suture clip as disclosed in U.S. Pat. No. 9,592,048 assigned to Edwards LifeSciences, Inc., Irvine, CA, the contents of which are hereby expressly incorporated herein. However, a variety of suture clips are known, and thus the clip 342 may be configured differently.

[0146] Another technique for collapsing the annulus after implantation involves the use of a balloon that pre-expands the prosthetic heart valve before anchoring at the annulus, followed by removal of the balloon to allow the valve to collapse through its inherent elasticity, thereby pulling the annulus inward. Fig.32A The delivery balloon 422 is shown to be maintained in an expanded state. Fig. 10A The entire implantation procedure is maintained via the vasculature while the heart is beating, so expansion of the balloon 422 occurs only when the valve with the valve support 420 is adjacent to the target annulus (in this case, the mitral annulus MA). The valve support 420 has a tubular valve portion 424 and an upper peripheral flange 426. The assembled heart valve can be formed by a single expandable superelastic support 420 covered with fabric, and the flexible valve leaflets are supported within the valve portion 424 to enable unidirectional blood to pass through the valve (downward for the mitral valve).

[0147] The balloon 422 expands the valve portion to a diameter that is approximately the same size as the native valve, which can be expanded according to a specific morphology. The surgeon advances the valve with the valve support 420 into the annulus via a guide wire 428 so that the tubular valve portion 424 fits tightly within the annulus and the peripheral flange 426 engages the annulus on the atrial side. The peripheral flange 426 may have a tissue anchor (such as barb 430 as shown) that pierces the atrial side of the annulus. Alternatively, once the peripheral flange 426 is placed against the annulus, a separate tissue anchor may be deployed around the peripheral flange.

[0148] Then, if Fig.32B As can be seen, the balloon 422 is deflated and removed from the implantation site. This allows the valve support 420 to assume a less relaxed shape, which pulls the valve annulus inward due to the anchors 430 on the peripheral flange 426. It should also be understood that the ventricular anchors (such as in Fig. 10D As seen in and as described below FIG. 33A to FIG. 33BThe anchors 106' described may also be part of the valve support 420 to also pull the leaflets inward, but a secondary positioning step is required. Although the balloon 442 is used to first expand and then allow contraction of the valve, contraction of the annulus is accomplished only by structures carried by or coupled to the valve, so the contraction mechanism is intrinsic to the valve.

[0149] Fig.33A The delivery balloon 442 is maintained in an expanded state and advanced toward the mitral valve annulus MA. Fig. 10C Another type of heart valve stent 440 is similar to the stent 100 ′. The entire implantation procedure is maintained via the vascular system while the heart is beating, so the expansion of the balloon 442 occurs only when the heart valve with the stent 440 is adjacent to the target valve annulus.

[0150] The valve stent 440 has a tubular valve portion 444 without an upper peripheral flange but with a ventricular anchor 446 that is curled downward from the lower end of the stent body 444 and curled back upward by about 180°. The ventricular anchor 446 can be configured to be retracted after implantation, such as by providing a band around its periphery, such as in Figure 7 8. The balloon 442 expands the valve portion to a diameter approximately the same as the size of the native valve, which can be expanded according to a specific morphology. The surgeon advances the valve with the valve support 440 into the annulus over the guide wire 448, so that the tubular valve portion 444 fits tightly in the annulus, and the ventricular anchor 446 is deployed to the outside of the mitral valve leaflets and is configured to collapse inwardly, as shown.

[0151] Then, if Fig.33B As seen, the balloon 442 is deflated and removed from the implant site. This enables the valve support 440 to assume a smaller relaxed shape, which pulls the annulus inwardly due to the ventricular anchors 446 surrounding the leaflets, as indicated by the movement arrows. Again, this is an intrinsic contraction mechanism.

[0152] Fig.34 4 is a perspective view of a further heart valve stent 460 having a tubular valve portion 462 illustrated as being formed of struts in a diamond pattern for contraction / expansion. The struts in the valve portion 462 converge at the inflow (upper) end at a junction 464 from which extend radially extending arms 466 terminated with anchoring barbs 468. The arms 466 radiate outward in a circular pattern to form an upper peripheral flange, and in the illustrated embodiment there are six arms, but there may be as few as four and more than six arms. In the assembled valve, the arms 466 are covered by a circular fabric panel that is aligned with the Fig.13A The 131 places seen in are very similar.

[0153] Fig.35 4 is a partial enlarged view of a section of a valve stent 460 with anchoring arms 466. The struts 470 in the valve portion 462 are shown in an extended and radially contracted delivery state, and the anchoring arms 466 are aligned and extended linearly. As will be described, the superelastic stent 460 is maintained in a linearly contracted state during transvascular delivery through an access tube or catheter. Once the valve reaches the implantation site, the surrounding constraints are removed, allowing the valve portion 462 to radially expand into a tube, and the anchoring arms 466 are bent radially outward to Fig.34 Approximately vertical orientation as seen.

[0154] FIG. 36A to FIG. 36C Delivery and implantation of a Fig.34 The sequence of the heart valve of the stent 460. The sheath 472 may have a tapered nose cone 474 that, as will be seen, can be disengaged from the proximal segment of the sheath, and the sheath is generally flexible to follow a guide wire 476 pre-installed at the implantation site. A traction suture or tether 478 passed through the sheath 472 from outside the body may be attached to the proximal end of the stent 460 (in this case the anchor barbs 468).

[0155] Initially in Fig.36A In the embodiment of the present invention, the heart valve is collapsed and retained within a tubular sheath 472, at least partially within a conical nose cone 474. The nose cone 474 is brought into the target valve annulus by advancing the sheath 472 over a guide wire 476.

[0156] Fig.36B The nose cone 474 is shown detached from the larger sheath 472 and advanced further past the target annulus. This first releases the constraints on the anchoring arms 466, allowing them to bend perpendicular to the tubular valve portion 462. As will be shown, the anchoring barbs 468 are configured to embed into the tissue of the surrounding annulus, which can be facilitated by using the inner shaft of the delivery system (not shown) to move the nose cone 474 further distally. Fig.34 As can be seen, arm 466 has a serpentine configuration that is initially linearly stretchable but contracts when released from delivery sheath 472. This pulls the surrounding annulus inwardly, as indicated by the radial arrows. Of course, any of the various contraction mechanisms described herein may be used with arm 466, such as, for example, the embodiments described with reference to FIGS. 13 to 16 , or other embodiments described herein.

[0157] Fig.36CA fully released stent 460 is shown with the tubular valve portion 462 radially expanded within the native valve leaflets and the proximal flange defined by radial arms 466 anchored in the surrounding tissue. The radial contraction from the arms 466 pulls the annulus inward against the valve portion 462, thereby improving anchoring and reducing paravalvular leakage around the valve. The traction suture 478 is shown released or loosened, which triggers better anchoring of the barbs 468, as described below.

[0158] The use of an externally controlled suture 478 in active barbs 468 means that the configuration is a hybrid contraction mechanism, but the radial contraction force is intrinsic and generated only by arms 466. If barbs 488 were instead passive and simply embedded in tissue or automatically activated once implanted, the entire contraction mechanism would be considered intrinsic.

[0159] Fig.37A and Fig.37B One configuration of anchoring barbs 468 of a stent 460 activated by a suture 478 in a tensioned state is illustrated. Each anchoring barb 468 includes a plate-like member 480 oriented to bear against tissue surrounding a target valve. A flexible portion 482 bends out of the plane of the plate-like member 480 from a similar incision 484. The flexible portion 482 includes a thin, curved finger 486 that cantilevers out from within the incision 484 and terminates in a barbed or forked end 488. In this embodiment, the suture 478 is passed through an external through hole in the plate-like member 480 and looped through a hole formed in the flexible portion 482. Maintaining tension on the suture 478 causes the flexible portion 482 to bend out of the incision 484. Once the tension in the suture 478 is released, the flexible portion 482 is allowed to flex back into the incision 484, as shown. Fig.37B The tension can be released by simply allowing one strand of the looped suture 478 to release, so that the entire suture can then be removed from the stent 460 by pulling on the other strand. When the flexible portion 482 flexes back to its relaxed position, the barbed or forked ends 488 are more deeply embedded in the annular tissue, thereby better anchoring the valve stent 460.

[0160] Fig.38 and Fig.39 Illustrated Fig.34 Two alternative configurations of the anchoring barbs of the stent. Fig.38 In the embodiment, the tensioning suture 478 is replaced by a rigid strut 490 having a forked end that engages the flexible portion 482. For example, the forked end may be coupled to a bending finger 486. In this embodiment, the flexible portion 482 is held in its bent position by the pushing force from the rigid strut 490, but is allowed to flex back toward the incision 484 when the strut 490 is removed. Fig.39A piece of bioresorbable material 492 is shown filling the cutout 484, which forces the flexible portion 482 to remain bent. After a period of time, such as perhaps 15 minutes, after implantation in the body, the bioresorbable material 492 dissolves, which allows the flexible portion 482 to return to its relaxed shape within the cutout 484. Fig.39 The embodiment of is an example of a completely internal retraction mechanism.

[0161] Fig.40 is with Fig.34 A perspective view of a heart valve stent 500 similar to the heart valve stent in , but having anchoring barbs only on some of the radially extending arms. Once again, the stent 500 has a tubular valve portion 502 defining a central axis, and a valve member having leaflets (not shown) is mounted within the tubular valve portion. When the stent is expanded, a plurality of arms 504 extend radially outward from the inflow end of the valve portion 502. Six arms 504 are shown, but only every other arm has an anchoring barb 506 on its outer end. As mentioned above, there may be as few as 4 and more than 6 arms 504, and the anchoring barbs 506 may be distributed differently, such as on every three arms. However, preferably, the anchoring barbs 506 are evenly distributed circumferentially around the peripheral flange defined by the arms 504.

[0162] Fig.40A yes Fig.34 and an enlarged view of an alternative type of anchoring barb 510 shown elsewhere. The anchoring barb 510 has the same Fig. 27 28 . The barbs 510 include a generally rectangular frame member 512 having openings in a plurality of inwardly directed teeth 514. Relatively protruding levers 516 at both ends of the frame 512 can be bent toward each other using the tensioning sutures 520 to flex the frame 512 and open the jaws defined by the teeth 514. Once the tension in the sutures 520 is released, the jaws flex again and close as described above. Again, this is a hybrid contraction mechanism in which an external suture 520 is used to actuate the barbs 510, but the contraction force is intrinsic to the valve structure.

[0163] Fig.41 is with Fig.34 A perspective view of yet another heart valve stent 530 similar to the heart valve stent in FIG. 5 but having radially extending arms of different lengths. A tubular valve portion 532 is connected to a plurality of radially extending arms at an upper end; a long arm 534 extends outwardly to a circumference 536, while a short arm 538 extends outwardly to a smaller circumference 540. Each of the arms 534, 538 terminates in an anchoring barb 542, but as described above, some of the arms may be devoid of anchoring barbs. Again, the number of arms may vary, and the pattern of short and long arms may also differ from the alternating pattern shown.

[0164] Fig.41A 5 is an enlarged view of another type of anchoring barb 550. A generally circular or oval frame 552 defines an opening 554 within which a plurality of teeth 558 extend. Oppositely protruding levers 556 provide through holes for tensioning sutures 560. By pulling on the sutures 560, the levers 526 bend the frame 552 open so that the teeth 558 protrude in a common direction. Once the tension in the sutures 560 is released, the teeth 558 come together again.

[0165] The various structures disclosed herein offer tremendous potential benefits. For example, shrinking the annulus (rather than pushing it outward to anchor) will better treat the underlying disease by reshaping the heart to its original shape. In addition, pulling on the annulus makes the frame less likely to contact the ventricular wall because the resulting shrunken diameter is smaller. The shrinkage also creates a tighter seal, which naturally reduces paravalvular (PV) leaks. In addition, firmly grasping or anchoring the inner valve frame to the annulus can eliminate the need for an outer frame used in some current solutions. Finally, shrinking the annulus surrounding the valve means that the valve is smaller overall compared to an outward expanding valve, which reduces the delivery profile, thereby having certain advantages in terms of reducing invasive delivery.

[0166] While the foregoing is a complete description of the preferred embodiments of the invention, various alternatives, modifications and equivalents may be used. In addition, it is apparent that certain other modifications may be practiced within the scope of the appended claims.

Claims

1. A prosthetic heart valve assembly for replacing a natural mitral valve or tricuspid valve, the prosthetic heart valve assembly comprising: a self-expandable stent having a body with an inlet end portion and an outlet end portion, the stent being made of a shape memory material; a valve portion positioned within a passage of the body, wherein the valve portion includes a plurality of leaflets made of pericardium, wherein the valve portion allows blood to flow through the passage in one direction to replace the function of a native valve; and a plurality of anchors disposed along an outer surface of the heart valve for engaging surrounding tissue; The prosthetic heart valve component is adapted to radially constrict the annulus of the native valve when deployed.

2. A prosthetic heart valve assembly as described in claim 1, wherein the stent further includes an annular flange extending radially outward from the inlet end portion of the body, and wherein the anchor is disposed along a surface of the annular flange.

3. A prosthetic heart valve assembly as described in claim 2, wherein the annular flange is capable of transforming from a large diameter to a small diameter for constricting the annulus of the native valve.

4. A prosthetic heart valve assembly as described in claim 3, wherein the annular flange includes a plurality of radial arms, wherein each arm is configured to decrease in length to constrict the annulus of the native valve.

5. The prosthetic heart valve assembly of claim 4, wherein each radial arm comprises a bioresorbable material that initially maintains the arm in an elongated state and that resorbs in vivo to allow the arm to transition to a shortened state.

6. The prosthetic heart valve assembly of claim 2, wherein the anchor comprises a barb.

7. The prosthetic heart valve assembly of claim 2, wherein the anchor comprises a helical screw.

8. The prosthetic heart valve assembly of claim 1, further comprising at least two ventricular anchors extending from the outlet end portion of the body.

9. The prosthetic heart valve assembly of claim 8, wherein the ventricular anchors are each shaped to capture native valve leaflets between the ventricular anchor and the body of the stent.

10. The prosthetic heart valve assembly of claim 8, wherein the ventricular anchor has an outer surface for engaging surrounding tissue.

11. The prosthetic heart valve assembly of claim 2, wherein a tightening mechanism is connected to each of the anchors, and wherein the tightening mechanism is adapted to pull the anchors radially inward for constricting the annulus of the native valve.

12. The prosthetic heart valve assembly of claim 2, wherein the anchor is not integrated into the heart valve and is deployed separately from the heart valve.

13. The prosthetic heart valve assembly of claim 2, wherein the annular flange is coupled to the body and is configured to decrease in diameter during radial expansion of the body.

14. A prosthetic heart valve assembly as described in claim 2, wherein the annular flange includes a plurality of spirally arranged arms, which have ends when expanded, and the ends collectively define a circle of rotation having a diameter D1, and wherein rotation of the valve portion about its axis pulls the arms inward so that the ends collectively define a contracted diameter D2.

15. A prosthetic heart valve assembly for replacing a natural mitral valve or tricuspid valve, the prosthetic heart valve assembly comprising: a self-expandable stent having a body with an inlet end portion and an outlet end portion, the stent being made of a shape memory material; a valve portion positioned within the passageway of the body, wherein the valve portion includes a plurality of leaflets made from pericardium, wherein the valve portion allows blood to flow through the passageway in one direction to replace the function of a native valve; as well as a plurality of anchors disposed along an outer surface of the stent for engaging surrounding tissue; The stent is adapted to be radially overexpanded by an expansion mechanism to a diameter greater than a shape-setting diameter for engaging surrounding tissue, and then to allow the stent to return to the shape-setting diameter upon removal of the expansion mechanism.

16. The prosthetic heart valve assembly of claim 15, wherein the expansion mechanism is a balloon.

17. The prosthetic heart valve assembly of claim 16, wherein the stent further comprises an annular flange extending radially outward from the inlet end portion of the body, and wherein the anchor is disposed along a surface of the annular flange.

18. The prosthetic heart valve assembly of claim 16, wherein the stent further comprises at least one ventricular anchor extending from the outlet end portion of the body.

19. The prosthetic heart valve assembly of claim 16, wherein the ventricular anchor is shaped to capture native valve leaflets between the ventricular anchor and the body of the stent.

20. A prosthetic heart valve assembly as described in claim 16, wherein the stent further includes an annular flange extending radially outward from the inlet end portion of the body and at least one ventricular anchor, wherein the at least one ventricular anchor is used to capture the natural valve leaflets between the ventricular anchor and the body of the stent.

21. The prosthetic heart valve assembly of claim 20, further comprising a fabric seal covering at least a portion of the stent.

22. A prosthetic heart valve assembly for replacing a natural mitral valve or tricuspid valve, the prosthetic heart valve assembly comprising: A self-expandable valve stent made of a shape memory material and covered with fabric, the valve stent having a tubular valve portion and a peripheral flange, the tubular valve portion having an inlet end portion and an outlet end portion, the peripheral flange being formed when expanded by an array of struts or arms extending radially outward from and connected to the inlet end portion, the array having an inherent radial contraction mechanism and a tissue engaging member; as well as a valve portion positioned within a passage of the subject, wherein the valve portion includes a plurality of leaflets made from pericardium, wherein the valve portion allows blood to flow through the passage in one direction to replace the function of a native valve; The prosthetic heart valve assembly is adapted to anchor the tissue engaging member to tissue surrounding the valve annulus to reduce the annulus upon deployment, thereby radially constricting the annulus of the native valve.

23. The prosthetic heart valve assembly of claim 22, wherein the array includes valve-like struts coupled to the valve portion such that expansion of the valve portion causes the struts to radially contract.

24. A prosthetic heart valve assembly as described in claim 22, wherein the array includes struts that are constructed to curl outwardly toward the valve portion and then curl inwardly when the external constraint surrounding the valve is removed from the inflow end, and the struts have barbs on the outer ends that define the tissue engaging members.

25. The prosthetic heart valve assembly of claim 22, wherein the array comprises a plurality of radially extending arms, each of the plurality of radially extending arms having a retraction mechanism for reducing the length of the embedded arm.

26. The prosthetic heart valve assembly of claim 25, wherein the retraction mechanism comprises an extension structure that is biased to a retracted length and is held extended by a bioresorbable suture.

27. The prosthetic heart valve assembly of claim 25, wherein the retraction mechanism comprises an extension structure that is biased to a retracted length and held extended by a reinforcing wire.

28. The prosthetic heart valve assembly of claim 25, wherein only some of the radially-extending arms have tissue engaging members thereon.

29. The prosthetic heart valve assembly of claim 25, wherein the radially extending arms have different lengths.

30. A prosthetic heart valve assembly as described in claim 22, wherein the array includes a plurality of helically arranged arms having ends when expanded, the ends collectively defining a circle of rotation having a diameter D1, and wherein rotation of the valve portion about its axis pulls the arms inwardly so that the ends collectively define a contracted diameter D2.

31. A prosthetic heart valve assembly as described in claim 22, wherein the valve stent has an outer anchoring stent and an inner valve stent, and the array includes a plurality of radial arms extending from a strut connected only at the lower end of the anchoring stent, wherein after the barbs are anchored at the ends of the radial arms, rotation of the anchoring stent causes the struts to rotate into a spiral shape and pull the ends inward, and then the inner valve stent expands within the outer anchoring stent.

32. A prosthetic heart valve assembly for replacing a natural mitral valve or tricuspid valve, the prosthetic heart valve assembly comprising: A self-expandable valve stent, the self-expandable valve stent being made of a shape memory material and covered with a fabric, the valve stent having a tubular valve portion and an arm array, the tubular valve portion having an inlet end portion and an outlet end portion, the arm array extending radially outward from the outlet end portion of the valve portion and connected to the outlet end portion and bending 180° toward the inlet end portion, the array having an inherent radial contraction mechanism and a tissue engaging member; as well as a valve portion positioned within a passage of the subject, wherein the valve portion includes a plurality of leaflets made from pericardium, wherein the valve portion allows blood to flow through the passage in one direction to replace the function of a native valve; The prosthetic heart valve component is adapted to anchor the tissue engaging member to native valve leaflets so as to draw the leaflets toward the tubular valve portion when deployed.

33. A prosthetic heart valve assembly as described in claim 32, wherein the intrinsic radial contraction mechanism includes a reinforcement tube mounted around a lower U-shaped bend on each of the arms, the reinforcement tube having a radius of curvature larger than the U-shaped bend to force the arms to an outward position, and the reinforcement tube is bioresorbable after a period of time in the body to allow the arms to return to a radially inward shape.

34. A prosthetic heart valve assembly as described in claim 32, wherein the intrinsic radial contraction mechanism includes one or more reinforcement plugs, which are mounted and positioned in a recessed portion on the inner radius of each of the arms, the reinforcement plugs maintain the arms in an outward position, and the reinforcement plugs are bioresorbable after a period of time in the body to allow the arms to return to a radially inward shape.

35. A system for collapsing an implantable prosthetic heart valve configured for implantation at a native mitral or tricuspid valve annulus, the system comprising: A heart valve having a fabric-covered self-expandable valve support having a tubular valve portion and a valve member having leaflets mounted therein, the valve further having a peripheral flange when expanded, the peripheral flange comprising a generally annular array of fabric-covered struts or arms extending radially outward from and connected to an inflow end of the valve portion, the array having tissue engaging members configured to grasp and anchor to tissue surrounding the valve annulus; as well as An external radial contraction mechanism is constructed to pull the tissue around the valve annulus inward after the tissue engaging members are deployed, and the external radial contraction mechanism includes a flexible band having a length sufficient to extend from outside the body and being threaded to connect and slide through each of the tissue engaging members, wherein tension on the band contracts the array and pulls the tissue around the valve annulus inward.

36. A system as described in claim 35, wherein the tissue engaging member includes a valve anchor that is separate from the peripheral flange and is deployed through the peripheral flange once the heart valve is positioned at the valve annulus.

37. The system of claim 35 wherein the array comprises a plurality of radially extending arms and the tissue engaging members comprise anchoring barbs secured to outer ends of at least some of the arms.

38. A system for collapsing an implantable prosthetic heart valve configured for implantation at a native mitral or tricuspid valve annulus, the system comprising: A heart valve having a fabric-covered self-expandable valve support having a tubular valve portion and a valve member having leaflets mounted therein, the valve further having a peripheral flange when expanded, the peripheral flange comprising a generally annular array of fabric-covered struts or arms extending radially outward from and connected to an inflow end of the valve portion, the array having tissue engaging members configured to grasp and anchor to tissue surrounding the valve annulus; and wherein the peripheral flanges are radially separated with free ends exposed on the inflow side of the peripheral flange; and An external radial contraction mechanism, which is constructed to pull the tissue around the valve ring inward after the tissue engaging member is deployed, and the external radial contraction mechanism includes a pair of flexible tethers, which have a length sufficient to extend from outside the body and are threaded to connect and slide through a pair of radially spaced anchors, which are embedded in the valve ring tissue through the peripheral flange and extend circumferentially along the peripheral flange to be attached to the free end of the peripheral flange, wherein the tension on the tethers contracts the peripheral flange and pulls the tissue around the valve ring inward.

39. A system for collapsing an implantable prosthetic heart valve configured for implantation at a native mitral or tricuspid valve annulus, the system comprising: A heart valve having a fabric-covered self-expandable valve support having a tubular valve portion and a valve member having leaflets mounted therein, the valve further having a peripheral flange when expanded, the peripheral flange comprising a generally annular array of fabric-covered struts or arms extending radially outwardly from and connected to an inflow end of the valve portion, a plurality of tissue anchors separate from the heart valve and configured to embed within tissue surrounding the valve annulus; and An external radial contraction mechanism is constructed to pull the tissue around the valve ring inward after the tissue anchor is deployed, and the external radial contraction mechanism includes a plurality of flexible tethers having a length sufficient to extend from outside the body, extend through the peripheral flange and extend radially outward to be fastened to the tissue anchor, wherein tension on the tethers contracts to pull the tissue anchor and the tissue around the peripheral flange inward.

40. A collapsible prosthetic heart valve for implantation at a native mitral or tricuspid valve annulus, the collapsible prosthetic heart valve comprising: A self-expandable valve stent covered with fabric, the valve stent having a tubular valve portion and a valve member having leaflets mounted therein, the valve further having a fabric-covered arm array extending radially outward from an outflow end of the valve portion and connected to the outflow end and bending 180° toward an inflow end, the array having tissue engaging members configured to grasp and anchor to leaflets attached to the valve annulus; as well as An external radial contraction mechanism, which is constructed to pull the leaflets attached to the valve annulus inwardly after the tissue engaging member is deployed, and the external radial contraction mechanism includes a flexible band having a length sufficient to extend from outside the body and being threaded to connect and slide through and completely surround the fabric covering the array, wherein tension on the band contracts the fabric-covered array and pulls the leaflets inwardly.

41. A collapsible prosthetic heart valve for implantation at a native mitral or tricuspid valve annulus, the collapsible prosthetic heart valve comprising: A self-expandable valve stent covered with fabric, the valve stent having a tubular valve portion and a valve member having leaflets mounted therein, the valve further having a fabric-covered outer tube spaced radially outwardly from the valve portion and connected to the valve portion by an upper flexible skirt and a lower flexible skirt, the outer tube having a tissue engaging member configured to grasp and anchor to the leaflets attached to the valve annulus; as well as An external radial contraction mechanism, which is constructed to pull the leaflets attached to the valve annulus inward after the tissue engaging member is deployed, and the external radial contraction mechanism includes a flexible band having a length sufficient to extend from outside the body and being threaded to connect and slide through and completely surround the fabric covering the outer tube, wherein tension on the band contracts the fabric-covered outer tube and pulls the leaflets inward.

42. A method of collapsing a prosthetic heart valve implanted at a native mitral or tricuspid valve annulus, the method comprising: A heart valve is provided, the heart valve having a fabric-covered self-expandable valve support, the valve support having a tubular valve portion and a valve member having leaflets mounted therein, the valve portion having a relaxed expanded size, the valve further having a peripheral flange when expanded, the peripheral flange comprising a generally annular array of fabric-covered struts or arms extending radially outward from and connected to an inflow end of the valve portion, the array having tissue engaging members configured to grasp and anchor to tissue surrounding the valve annulus; preparing the heart valve for implantation by crimping the heart valve around a balloon and constraining the heart valve in a contracted state within an access sheath; advancing the heart valve in the contracted state in the access sheath to the valve annulus; expelling the heart valve from the access sheath within the valve annulus; inflating the balloon beyond the expanded size of the valve portion of the valve stent; anchoring the tissue engaging member into tissue surrounding the valve annulus; as well as The balloon is deflated to allow the valve portion to collapse to its expanded size and draw the peripheral flange inwardly.

43. A method of collapsing a prosthetic heart valve implanted at a native mitral or tricuspid valve annulus, the method comprising: A self-expandable valve stent is provided, the self-expandable valve stent is covered with fabric, the valve stent has a tubular valve portion and a valve member in which a leaflet is installed, the valve portion has a relaxed expanded size, the valve further has a fabric-covered arm array, the fabric-covered arm array extends radially outward from an outflow end of the valve portion and is connected to the outflow end and is bent 180° toward and towards the inflow end, the array has a tissue engaging member, the tissue engaging member is configured to grasp and anchor to the leaflet attached to the valve annulus; preparing the heart valve for implantation by crimping the heart valve around a balloon and constraining the heart valve in a contracted state within an access sheath; advancing the heart valve in the contracted state in the access sheath to the valve annulus; expelling the heart valve from the access sheath within the valve annulus; inflating the balloon beyond the expanded size of the valve portion of the valve stent; anchoring the tissue engaging member into the leaflet; as well as The balloon is deflated to allow the valve portion to collapse to its expanded size and draw the array inward.

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