Patent Description:
This document relates to prosthetic heart valves, such as prosthetic mitral valves that can be implanted using transcatheter techniques. This document also relates to systems and methods for implanting a two-part prosthetic heart valve that is arranged in a nested configuration during the transcatheter delivery and deployment processes. The invention relates to a transcatheter mitral valve replacement system for a heart as defined in claim <NUM>. Particular embodiments are defined in dependent claims <NUM> - <NUM>.

The long-term clinical effect of valve regurgitation is recognized as a significant contributor to cardiovascular related morbidity and mortality. Thus, for many therapies intended to treat the mitral valve, one primary goal is to significantly reduce or eliminate regurgitation. By eliminating the regurgitation at the mitral valve, the destructive volume overload effects on the left ventricle can be attenuated. The volume overload of mitral regurgitation (MR) relates to the excessive kinetic energy required during isotonic contraction to generate overall stroke volume in an attempt to maintain forward stroke volume and cardiac output. It also relates to the pressure potential energy dissipation of the leaking valve during the most energy-consuming portion of the cardiac cycle, isovolumetric contraction. Additionally, therapies for MR reduction can have the effect of reducing the elevated pressures in the left atrium and pulmonary vasculature reducing pulmonary edema (congestion) and shortness of breath symptomatology. Such therapies for MR reduction may also have a positive effect on the filling profile of the left ventricle (LV) and the restrictive LV physiology that can result with MR. These pathophysiologic issues indicate the potential benefits of MR therapy, but also indicate the complexity of the system and the need for a therapy to focus beyond the MR level or grade.

In some percutaneous access procedures in which a medical device is introduced through a patient's skin and into a patient's blood vessel, such an access can be used to introduce devices into the patient without the use of large cut downs, which can be painful and in some cases can hemorrhage or become infected. A percutaneous access generally employs only a small hole through the skin, which subsequently seals relatively easily, and heals quickly in comparison to a surgical cut down.

<CIT> discloses a two-part prosthetic mitral valve delivered by a catheter having an outer sheath.

This document describes prosthetic heart valves, such as prosthetic mitral valves, that interface and anchor in cooperation with the anatomical structures of a native mitral valve. In addition, this document describes systems and methods for implanting a two-part prosthetic heart valve in which two expandable components are arranged in a nested configuration during both the transcatheter delivery process and the deployment process within the heart.

The invention is directed to a transcatheter mitral valve replacement system for a heart. The transcatheter mitral valve replacement system includes a delivery sheath having a distal end portion insertable into a left atrium, a delivery catheter slidably disposed within the delivery sheath, and a two-part prosthetic mitral valve coupled to the delivery catheter by one or more control wires. The two-part prosthetic mitral valve is configured to be disposed within the delivery sheath in a radially compressed condition and to radially self-expand when the two-part prosthetic mitral valve is outside of the delivery sheath and is unconstrained by the one or more control wires. The two-part prosthetic mitral valve includes a valve assembly including an expandable valve frame and a tri-leaflet occluder and an anchor assembly separately expandable from the valve assembly and defining an interior space within which the valve assembly is nested while the two-part prosthetic mitral valve is within the delivery sheath for simultaneous deployment from the delivery sheath. The system also includes a pusher catheter slidably disposed within the deliver catheter and releasably coupled to the anchor assembly. The one or more control wires may include: a first control wire coupled to a proximal end portion of the anchor assembly; a second control wire coupled to a mid-body portion of the anchor assembly; a third control wire coupled to a proximal end portion of the valve assembly; and a fourth control wire coupled to a distal end portion of the valve assembly. The one or more control wires may include: a first control wire coupled to a proximal end portion of the anchor assembly; a second control wire coupled to a proximal end portion of the valve assembly; and a third control wire coupled to a distal end portion of the valve assembly. The one or more control wires may include: a first control wire coupled to a proximal end portion of the anchor assembly and to a proximal end portion of the valve assembly; a second control wire coupled to a mid-body portion of the anchor assembly; and a third control wire coupled to a distal end portion of the valve assembly. The one or more control wires may include: a first control wire coupled to a proximal end portion of the anchor assembly and to a proximal end portion of the valve assembly; and a second control wire coupled to a distal end portion of the valve assembly. A mid-body portion of the valve assembly may have a D-shaped cross-sectional shape. The anchor assembly may include four feet configured to reside within a sub-annular gutter of a native mitral valve when the two-part prosthetic mitral valve is implanted within the heart. The anchor assembly may include supra-annular features including an undulating supra-annular ring that defines an end of the interior space and atrial holding features configured to contact supra-annular tissue surfaces above an annulus of the mitral valve. The system may also include a deployment control system coupled to proximal ends of the delivery sheath and the delivery catheter. The deployment control system may include mechanisms for adjusting tension applied to the one or more control wires.

Not forming part of the invention, this disclosure is directed to a method for deploying a transcatheter prosthetic mitral valve system within a native mitral valve of a patient. The method may include: navigating a delivery sheath within the vasculature of the patient such that a distal end portion of the delivery sheath is positioned within a left atrium of the patient. The delivery sheath contains a two-part prosthetic mitral valve in a radially compressed condition and comprising: a valve assembly including an expandable valve frame and a tri-leaflet occluder; and an anchor assembly including an expandable anchor frame separate from the expandable valve frame of the valve assembly and defining an interior space within which the valve assembly is disposed while the two-part prosthetic mitral valve is within the delivery sheath. The method may also include expressing, in the left atrium, the two-part prosthetic mitral valve. A delivery catheter is releasably engaged with the two-part prosthetic mitral valve using one or more control wires. The valve assembly remains disposed within the interior space defined by the anchor assembly during and after the expressing. The method may also include engaging the anchor assembly with the native mitral valve. The anchor assembly is in a radially expanded condition while engaged with the native mitral valve. The method may also include, after the engaging the anchor assembly in in the radially expanded condition, expanding the valve assembly within the interior space to couple the valve assembly to the anchor assembly.

Such a method for deploying a transcatheter prosthetic mitral valve system within a native mitral valve of a patient may optionally include one or more of the following features. The expanding the valve assembly may include relieving tension of the one or more control wires to allow the valve assembly to self-expand. The engaging the anchor assembly with the native mitral valve may include relieving tension of the one or more control wires to allow the anchor assembly to self-expand and positioning four feet of the anchor assembly within a sub-annular gutter of the native mitral valve. The engaging the anchor assembly with the native mitral valve may also include positioning atrial holding features of the anchor assembly adjacent to supra-annular tissue surfaces above an annulus of the mitral valve.

Not forming part of the invention, this disclosure is directed to a two-part prosthetic heart valve having two separately expandable components arranged in a nested configuration for transcatheter delivery to a heart. The two-part prosthetic heart valve includes an anchor assembly including an expandable anchor frame defining an interior space and defining a plurality of sub-annular anchor feet. The anchor assembly is expandable from a compressed anchor delivery configuration to an expanded anchor deployment configuration in which the sub-annular anchor feet are sized and shaped to engage along an underside of a mitral valve annulus. The two-part prosthetic heart valve also includes a valve assembly including an expandable valve frame that is separately expandable from the expandable anchor frame. The valve assembly is nested within the interior space of the expandable anchor frame while the anchor assembly is in the compressed anchor delivery configuration. The expandable valve frame defines a central orifice and a leaflet occluder positioned within the central orifice. The valve assembly is expandable from a compressed valve delivery configuration to an expanded valve deployment configuration after the anchor assembly is in the expanded anchor deployment configuration.

Such a two-part prosthetic heart valve may optionally include one or more of the following optional features. The plurality of sub-annular anchor feet of the anchor assembly may include four anchor feet configured to reside within a sub-annular gutter of a native mitral valve when the anchor assembly is in the expanded anchor deployment configuration. The anchor assembly may include a supra-annular element including an undulating supra-annular ring that defines an uppermost end of the interior space and atrial holding elements configured to contact supra-annular tissue above the mitral valve annulus.

Not forming part of the invention, this disclosure is directed to a method of deploying a two-part prosthetic heart valve having two separately expandable components arranged in a nested configuration during transcatheter delivery to a heart. The method includes delivering a valve assembly having an expandable valve frame to the heart while nested within a separately expandable anchor frame of an anchor assembly in a compressed anchor delivery configuration, and contemporaneously deploying the valve assembly and the anchor assembly into the heart while the valve assembly is nested within the anchor assembly.

Such a method of deploying a two-part prosthetic heart valve having two separately expandable components arranged in a nested configuration during transcatheter delivery to a heart may optionally include one or more of the following features. The method may also include expanding the anchor assembly from the compressed anchor delivery configuration to an expanded anchor deployment configuration in which sub-annular anchor feet of the anchor assembly engage along an underside of a mitral valve annulus. The method may also include, after expanding the anchor assembly to the expanded anchor deployment configuration, expanding the valve assembly from a compressed valve configuration to an expanded valve deployment configuration in which the valve assembly mechanically mates to an interior region of the anchor assembly.

Some or all of the embodiments described herein may provide one or more of the following advantages. First, using the devices, systems, and methods described herein, various medical conditions, such as heart valve conditions, can be treated in a minimally invasive fashion. Such minimally invasive techniques can tend to reduce recovery times, patient discomfort, and treatment costs.

Second, the devices, systems, and methods described herein facilitate the implantation of a two-part prosthetic heart valve in which two expandable components are arranged in a nested configuration during the transcatheter delivery and deployment processes. Accordingly, the time to complete the procedure is advantageously minimalized. This can result in reduced time in the operating room, lessened patient risks, and lower procedural costs.

Third, the transcatheter prosthetic heart valve and deployment systems described herein are configured to facilitate accurate control of the prosthetic valve components during the delivery and deployment process. In some embodiments, one or more control wires are coupled to end portions or middle portions of the prosthetic valve components in a manner that allows for isolated, accurate movements of each degree of freedom associated with the catheters and prosthetic valve components. Accordingly, relatively complex catheter and/or valve component movements are facilitated in an accurately controllable and user-convenient manner. In result, transcatheter implant procedures can be performed with enhanced patient safety and treatment efficacy using the devices, systems, and methods described herein.

Fourth, some embodiments of the prosthetic mitral valve and deployment systems described herein can be used in a completely percutaneous/transcatheter mitral replacement procedure that is streamlined, safe, reliable, and repeatable by surgeons and/or interventional cardiologists of a variety of different skill levels.

Fourth, in particular embodiments, the two-part prosthetic mitral valve can optionally include two different expandable components (e.g., an anchor assembly and a valve assembly) that are delivered to the implantation site in a nested arrangement. For example, the first component (e.g., the anchor assembly including a first expandable frame) can be configured to engage with the heart tissue that is at or proximate to the annulus of the native mitral valve, and the second component (e.g., the valve assembly including a second expandable frame) can be configured to provide a seal interface with native valve leaflets of the mitral valve.

Fifth, using the systems and methods for implanting a two-part prosthetic heart valve that is arranged in a nested configuration during the transcatheter delivery and deployment processes, patients can be treated while guarding the patients' hemodynamic stability during the implantation process. Such devices and techniques can tend to reduce the need for ancillary interventions, such as the need for installing a balloon pump and the like.

This document describes prosthetic heart valves, such as prosthetic mitral valves, that interface and anchor in cooperation with the anatomical structures of a native mitral valve. In addition, this document describes systems and methods for implanting a two-part prosthetic heart valve in which two expandable components are arranged in a nested configuration during the transcatheter delivery and deployment processes.

Referring to <FIG>, in some therapeutic medical procedures a two-part prosthetic mitral valve <NUM> can be deployed in a patient <NUM> using a transcatheter delivery system <NUM>. In some implementations, the prosthetic mitral valve <NUM> is percutaneously deployed via a femoral or iliac vein through a groin opening/incision <NUM> in the patient <NUM> in a minimally invasive fashion. In particular implementations, a deployment control system <NUM> is used to initiate and/or control the movements of various components of the transcatheter delivery system <NUM>, and of the prosthetic mitral valve <NUM>, as described further below.

The two-part prosthetic mitral valve <NUM> can be delivered to and implanted in the heart <NUM> using a percutaneous, or minimally invasive, technique via the venous or arterial system (without open-chest or open-heart surgery). In some implementations, the transcatheter delivery system <NUM> and prosthetic mitral valve <NUM> are used in conjunction with one or more imaging modalities such as x-ray fluoroscopy, echocardiography, magnetic resonance imaging, computed tomography (CT), and the like. Accordingly, various components of the transcatheter delivery system <NUM> and/or the prosthetic mitral valve <NUM> can include one or more features to enhance their visibilities under imaging modalities, such as radio-opaque markers.

Early steps of the process for deploying the two-part prosthetic mitral valve <NUM> includes the placement of a guidewire <NUM> (refer to <FIG>) within the vasculature and heart <NUM> of the patient <NUM>. In the depicted implementation, the guidewire <NUM> is installed into the heart <NUM> prior to the other components of the delivery system <NUM>. In some embodiments, the guidewire <NUM> has a diameter of about <NUM> inches (about <NUM>). In some embodiments, the guidewire <NUM> has a diameter in a range of about <NUM> inches to about <NUM> inches (about <NUM> to about <NUM>). In some embodiments, the guidewire <NUM> has a diameter smaller than <NUM> inches (about <NUM>) or larger than <NUM> inches (about <NUM>). In some embodiments, the guidewire <NUM> is made of materials such as, but not limited to, nitinol, stainless steel, high-tensile-strength stainless steel, and the like, and combinations thereof. The guidewire <NUM> may include various tip designs (e.g., J-tip, straight tip, etc.), tapers, coatings, covers, radiopaque (RO) markers, and other features. In some embodiments, the guidewire <NUM> has one or more portions with differing lateral stiffnesses, column strengths, lubricity, and/or other physical properties in comparison to other portions of the guidewire <NUM>.

In some implementations, the guidewire <NUM> is percutaneously inserted into a femoral vein of the patient <NUM>. The guidewire <NUM> is routed to the inferior vena cava and into the right atrium. After creating an opening in the atrial septum (e.g., a trans-septal puncture of the fossa ovalis or other portion of the atrial septum), the guidewire <NUM> is routed into the left atrium <NUM>. Lastly, the guidewire <NUM> is routed through the mitral valve <NUM> and into the left ventricle <NUM>. This is preferably performed without entangling the guidewire <NUM> with the chordae tendineae <NUM> of the mitral valve <NUM>. In some implementations, the guidewire <NUM> can be installed into the heart <NUM> along other anatomical pathways. The guidewire <NUM> thereafter serves as a rail over which other components of the delivery system <NUM> are passed.

The transcatheter delivery system <NUM> facilitates implantation of the two-part prosthetic mitral valve <NUM> in the heart <NUM> while the heart <NUM> is beating. Using interventional cardiology techniques, the transcatheter prosthetic heart valve delivery system <NUM> can be navigated through the venous vasculature of the patient <NUM>, and through the atrial septum (e.g., a trans-septal puncture of the fossa ovalis or other portion of the atrial septum), to obtain access to the left atrium <NUM> of the patient's heart <NUM>. <FIG> shows the two-part prosthetic mitral valve <NUM> fully deployed within the native mitral valve such that the prosthetic mitral valve <NUM> is performing the mitral valve function.

In the depicted embodiment, the example two-part prosthetic mitral valve <NUM> includes an anchor assembly <NUM> (including a first expandable frame structure) and a separate valve assembly <NUM> (including a second expandable frame structure). The valve assembly <NUM> is sized and shaped to releasably mount to the framework of the anchor assembly <NUM>.

In the depicted embodiment, the anchor assembly <NUM> includes four anchor feet: a lateral anterior foot 220a, a lateral posterior foot 220b, a medial posterior foot 220c, and a medial anterior foot 220d. In some embodiments, fewer or more anchor feet may be included (e.g., two, three, five, six, or more than six). In some embodiments, the anchor feet 220a, 220b, 220c, and 220d are portions of the anchor assembly <NUM> that are configured for contact with a sub-annular gutter <NUM> of the native mitral valve <NUM>, without penetrating tissue of the native mitral valve <NUM>. Accordingly, the anchor feet 220a, 220b, 220c, and 220d have atraumatic surfaces that are generally comparable to feet. However, in some embodiments one or more of the anchor feet 220a, 220b, 220c, and 220d are configured to penetrate tissue and may have anchor features such as barbs, coils, hooks, and the like.

It should be understood that the depicted anchor assembly <NUM> is merely one non-limiting example of the anchor assemblies included within the scope of this disclosure.

In some embodiments, the anchor assembly <NUM> includes supra-annular structures and sub-annular structures. For example, in some embodiments the sub-annular structures of the anchor assembly <NUM> can include the aforementioned anchor feet 220a, 220b, 220c, and 220d, a systolic anterior motion (SAM) containment member <NUM>, and a hub <NUM>. The SAM containment member <NUM> is designed to inhibit the incursion of an anterior leaflet of the native mitral valve into the LVOT during systole, which might otherwise cause LVOT obstruction or the creation of high LVOT pressure gradients. In some embodiments, the hub <NUM> functions as a connection structure for the delivery system <NUM>. In addition, the hub <NUM> can function as a stabilizing structural component from which a lateral anterior sub-annular support arm 230a and a medial anterior sub-annular support arm 230d extend to the anchor feet 220a and 220d respectively. In some embodiments, a lateral posterior sub-annular support arm 230b extends from the lateral anterior sub-annular support arm 230a to the lateral posterior foot 220b. In some embodiments, a medial posterior sub-annular support arm 230c extends from the medial anterior sub-annular support arm 230d to the medial posterior foot 220c.

In the depicted embodiment, the supra-annular structures of the anchor assembly <NUM> include: a lateral anterior atrial holding feature 240a, a posterior atrial holding feature 240b, and a medial anterior atrial holding feature 240c; a lateral anterior anchor arch 250a, a posterior anchor arch 250b, and a medial anterior anchor arch 250c. The lateral anterior anchor arch 250a, the posterior anchor arch 250b, and the medial anterior anchor arch 250c are joined with each other to form an undulating supra-annular ring <NUM> that acts as a supra-annular structural element for the anchor assembly <NUM>. The supra-annular ring <NUM> also defines an opening to a space within the interior of the anchor assembly <NUM> that is configured to receive and engage with the valve assembly <NUM>. The atrial holding features 240a, 240b, and 240c are configured to contact the shelf-like supra-annular tissue surface above the mitral valve annulus, and to thereby stabilize the anchor assembly <NUM> in supra-annular areas and to provide migration resistance in the direction towards the left ventricle <NUM>.

The valve assembly <NUM> includes a proximal end portion <NUM> and a distal end portion <NUM>. When the valve assembly <NUM> is implanted in a native mitral valve, the proximal end portion <NUM> is located supra-annular (in the left atrium <NUM>) and the distal end portion <NUM> is located sub-annular (in the left ventricle <NUM>). The proximal end portion <NUM> defines the generally circular entrance orifice of the valve assembly <NUM>. At least three prosthetic valve leaflets (not visible) are located within the valve assembly <NUM>.

It should be understood that the depicted valve assembly <NUM> is merely one non-limiting example of the valve assemblies included within the scope of this disclosure.

In the depicted embodiment, the valve assembly <NUM> generally flares outward along a distal direction. Said differently, the distal end portion <NUM> is flared outward in comparison to the proximal end portion <NUM>. Accordingly, the proximal end portion <NUM> defines a smaller outer profile in comparison to the distal end portion <NUM>. However, some regions of the distal end portion <NUM> bow inwardly. Such inward bowing can serve to mitigate LVOT obstructions and enhance sealing in some cases.

In some embodiments, the periphery of the distal end portion <NUM> is generally D-shaped in cross-section. The D-shaped periphery of the distal end portion <NUM> provides the valve assembly <NUM> with an advantageous outer profile for interfacing and sealing with the native mitral valve. For example, in some implementations sealing is attained by coaptation between the D-shaped periphery of the distal end portion <NUM> and the leaflets of the native mitral valve.

In the depicted embodiment, the proximal end portion <NUM> of the valve assembly <NUM> includes three atrial leaflet arches 310a, 310b, and 310c that together define an undulating ring at the proximal end portion <NUM>. Each of the leaflet arches 310a, 310b, and 310c includes an apex having one or more holes 312a, 312b, and 312c respectively. In some embodiments, the holes 312a, 312b, and 312c are used for coupling the proximal end of the valve assembly <NUM> to a delivery catheter using a proximal control wire. In some embodiments, one or more of the holes 312a, 312b, and 312c are used for containing radiopaque material.

In some embodiments, such as the depicted embodiment, valve assembly <NUM> includes three leaflets (not visible) that perform the occluding function of the prosthetic mitral valve <NUM>. The cusps of the three leaflets are fixed to the three atrial leaflet arches 310a, 310b, and 310c, and to three commissural posts (not visible) that each extend distally from the intersections of the three leaflet arches 310a, 310b, and 310c. In some embodiments, the three commissural posts are disposed at about <NUM>° apart from each other. The commissural posts each have a series of holes that can be used for attachment of the prosthetic valve leaflets, such as by suturing. The three leaflet arches 310a, 310b, and 310c and the three commissural posts are areas on the valve assembly <NUM> to which the three prosthetic valve leaflets become attached to comprise a tri-leaflet occluder. As such, the valve assembly <NUM> provides a proven and advantageous frame configuration for the tri-leaflet occluder. When implanted in the native mitral valve <NUM>, the tri-leaflet occluder of the valve assembly <NUM> provides open flow during diastole and occlusion of flow during systole. The free edges of the three leaflets can seal by coaptation with each other during systole and open during diastole.

The three leaflets can be comprised of natural or synthetic materials. For example, the three leaflets can be comprised of any of the materials described below in reference to the coverings <NUM> and/or <NUM>, including the natural tissues such as, but not limited to, bovine, porcine, ovine, or equine pericardium. In some such embodiments, the tissues are chemically cross-linked using glutaraldehyde, formaldehyde, or triglycidyl amine solution, or other suitable crosslinking agents. In some embodiments, the leaflets have a thickness in a range of about <NUM>" to about <NUM>" (about <NUM> to about <NUM>), or about <NUM>" to about <NUM>" (about <NUM> to about <NUM>). In some embodiments, the leaflets have a thickness that is less than about <NUM>" (about <NUM>) or greater than about <NUM>" (about <NUM>).

In some embodiments, the occluding function of the prosthetic mitral valve <NUM> can be performed using configurations other than a tri-leaflet occluder. For example, bi-leaflet, quad-leaflet, or mechanical valve constructs can be used in some embodiments.

As shown in <FIG>, in some embodiments the anchor assembly <NUM> includes a covering material <NUM> disposed on one or more portions of the anchor assembly <NUM> and/or the valve assembly <NUM> includes a covering material <NUM> disposed on one or more portion of the valve assembly <NUM>. The covering materials <NUM>/<NUM> can provide various benefits. For example, in some implementations the covering materials <NUM>/<NUM> can facilitate tissue ingrowth and/or endothelialization, thereby enhancing the migration resistance of the anchor assembly <NUM> and/or valve assembly <NUM>, and preventing thrombus formation on blood contact elements. In another example, as described further below, the covering materials <NUM>/<NUM> can be used to facilitate coupling between the anchor assembly <NUM> and the valve assembly <NUM> that is received therein. The cover materials <NUM>/<NUM> also prevent or minimizes abrasion and/or fretting between the anchor assembly <NUM> and valve assembly <NUM> to enhance durability. The covering materials <NUM>/<NUM> are omitted in <FIG> to provide enhanced visualization of the interface between the anchor assembly <NUM> and valve assembly <NUM> with the native mitral valve <NUM>.

In some embodiments, the covering materials <NUM>/<NUM>, or portions thereof, comprises a fluoropolymer, such as an expanded polytetrafluoroethylene (ePTFE) polymer. In some embodiments, the covering materials <NUM>/<NUM>, or portions thereof, comprises a polyester, a silicone, a urethane, ELAST-EON™ (a silicone and urethane polymer), another biocompatible polymer, DACRON®, polyethylene terephthalate (PET), copolymers, or combinations and subcombinations thereof. In some embodiments, the covering materials <NUM>/<NUM>, or portions thereof, comprises a biological tissue. For example, in some embodiments the covering materials <NUM>/<NUM> can include natural tissues such as, but not limited to, bovine, porcine, ovine, or equine pericardium. In some such embodiments, the tissues are chemically treated using glutaraldehyde, formaldehyde, or triglycidylamine (TGA) solutions, or other suitable tissue crosslinking agents.

In some embodiments, the anchor assembly <NUM> can include features that are designed for mechanically mating with the valve assembly <NUM> that is received by the anchor assembly <NUM>. For example, the lateral anterior anchor arch 250a, the posterior anchor arch 250b, and the medial anterior anchor arch 250c can be shaped and arranged for coupling with the valve assembly <NUM>. In addition, in some embodiments the anchor arches 250a, 250b, and 250c can include one or more covering-material cut-outs 252a, 252b, and 252c respectively. In some embodiments, the valve assembly <NUM> can include a fabric portion 314a (and fabric portions 314b and 314b; not visible) that become physically disposed within the covering-material cut-outs 252a, 252b, and 252c when the valve assembly <NUM> is coupled with the anchor assembly <NUM>. Such an arrangement can serve to provide a robust coupling arrangement between the valve assembly <NUM> and the anchor assembly <NUM>.

In some embodiments, the expandable frame structure of the anchor assembly <NUM> and/or the expandable frame structure of the valve assembly <NUM> are formed from a single piece of precursor material (e.g., sheet or tube) that is cut and expanded (and then connected to the hub <NUM> in the case of the anchor assembly <NUM>). For example, some embodiments are fabricated from a tube that is laser-cut (or machined, chemically etched, water-jet cut, etc.) and then expanded and heat-set into its final expanded size and shape. In some embodiments, the expandable frame structure of the anchor assembly <NUM> is created compositely from multiple elongate members (e.g., wires or cut members) that are joined together with the hub <NUM> and each other to form the anchor assembly <NUM>.

The expandable frame structure of the anchor assembly <NUM> and/or the expandable frame structure of the valve assembly <NUM> can comprise various materials and combinations of materials. In some embodiments, nitinol (NiTi) is used as the material of the elongate members of the expandable frame structure of the anchor assembly <NUM> and/or the valve assembly <NUM>, but other materials such as stainless steel, L605 steel, polymers, MP35N steel, stainless steels, titanium, cobalt/chromium alloy, polymeric materials, Pyhnox, Elgiloy, or any other appropriate biocompatible material, and combinations thereof can be used. The super-elastic properties of NiTi make it a particularly good candidate material for the elongate members of the expandable frame structure of the anchor assembly <NUM> and/or the valve assembly <NUM> because, for example, NiTi can be heat-set into a desired shape. That is, NiTi can be heat-set so that the anchor assembly <NUM> and/or the valve assembly <NUM> tends to self-expand into a desired shape when the anchor assembly <NUM> and/or the valve assembly <NUM> is unconstrained, such as when the anchor assembly <NUM> and/or the valve assembly <NUM> is deployed out from the anchor delivery sheath <NUM>. An expandable frame structure of the anchor assembly <NUM> and/or the valve assembly <NUM> made of NiTi, for example, may have a spring nature that allows the anchor assembly <NUM> and/or the valve assembly <NUM> to be elastically collapsed or "crushed" to a low-profile delivery configuration and then to self-expand to the expanded configuration. The anchor assembly <NUM> and/or the valve assembly <NUM> may be generally conformable, fatigue resistant, and elastic to conform to the topography of the surrounding tissue when the anchor assembly <NUM> and/or the valve assembly <NUM> is deployed in the native mitral valve <NUM> of the patient <NUM>.

Still referring to <FIG>, the anchor feet 220a, 220b, 220c, and 220d are sized and shaped to engage the sub-annular gutter <NUM> of the mitral valve <NUM>. In some embodiments, the anterior feet 220a and 220d are spaced apart from each other by a distance in a range of about <NUM> to about <NUM>, or about <NUM> to about <NUM>, or about <NUM> to about <NUM>. In some embodiments, the posterior feet 220b and 220c are spaced apart from each other by a distance in a range of about <NUM> to about <NUM>, or about <NUM> to about <NUM>, or about <NUM> to about <NUM>.

In some embodiments, the anchor feet 220a, 220b, 220c, and 220d have a height ranging from about <NUM> to about <NUM>, or more than about <NUM>. In some embodiments, the anchor feet 220a, 220b, 220c, and 220d have a gutter engaging surface area (when fabric covered) ranging from about <NUM><NUM> to about <NUM><NUM>. In some embodiments, the anchor feet 220a, 220b, 220c, and 220d each have essentially the same gutter engaging surface area. In particular embodiments, one or more of the anchor feet 220a, 220b, 220c, and 220d has a different gutter engaging surface area than one or more of the other anchor feet 220a, 220b, 220c, and 220d. The anchor feet 220a, 220b, 220c, and 220d can have widths ranging within about <NUM> to about <NUM> or more, and lengths ranging within about <NUM> to about <NUM> or more. The anchor feet 220a, 220b, 220c, and 220d are sized and shaped so that the anchor assembly <NUM> does not significantly impair the natural function of mitral valve chordae tendineae <NUM>, the native mitral valve leaflets, and papillary muscles even after the anchor assembly <NUM> is anchored at the mitral valve site.

Referring to <FIG>, the two-part prosthetic mitral valve <NUM> can be schematically depicted (e.g., shown here in an exploded view corresponding to <FIG>) to make the transcatheter deployment technique described below easier to visualize and understand. As described above, the two-part prosthetic mitral valve <NUM> includes the anchor assembly <NUM> (including the hub <NUM>) and the valve assembly <NUM>. The valve assembly <NUM> is removably receivable within the interior space of the anchor assembly <NUM> as described above. In this figure (and in <FIG> and <FIG>), the anchor assembly <NUM> is schematically shown in solid lines, while the valve assembly <NUM> is schematically shown in dashed lines for illustrative purposes. Those different line types (solid lines and dashed lines) are being used solely to help the viewer clearly distinguish the anchor assembly <NUM> from the valve assembly <NUM>. The use of the solid lines and dashed lines in this figure (and in <FIG> and <FIG>) is provided for clarity of viewing of the two assemblies <NUM> and <NUM> in the nested arrangement, but the use of the dashed lines in this figure (and in <FIG> and <FIG>) does not necessarily mean the elements shown in dashed lines are hidden or concealed from view.

Referring to <FIG>, in some implementations the valve assembly <NUM> is positioned within the anchor assembly <NUM> during the transcatheter delivery and deployment processes. The two devices (e.g., the anchor assembly <NUM> and the valve assembly <NUM>) can be separate devices having different frame structures that are independently expandable from one another, but with one device laterally surrounding the other device so that when they are radially expanded in situ, the anchor assembly <NUM> and the valve assembly <NUM> will be mechanically mated together. As such, the two-part prosthetic heart valve <NUM> includes two expandable components that are arranged in a nested configuration during both the transcatheter delivery process and the deployment process within the heart.

In some implementations, a sheath <NUM> (which is a part of the transcatheter delivery system <NUM>) can be used to simultaneously deliver the anchor assembly <NUM> and the valve assembly <NUM> to the heart <NUM>. That is, the anchor assembly <NUM> and the valve assembly <NUM> can be elastically collapsed to reduced diameters and constrained within the confines of the low-profile sheath <NUM>. In that arrangement, the sheath <NUM> (containing the anchor assembly <NUM> and the valve assembly <NUM> in radially collapsed configurations) can be navigated through the patient's vasculature and heart to arrive at the target location (e.g., within the heart proximate to the patient's native mitral valve). There, the anchor assembly <NUM> and the valve assembly <NUM> can be expressed out of the sheath <NUM>. <FIG> depicts the anchor assembly <NUM> and the valve assembly <NUM> after having been expressed from the sheath <NUM>. As shown in this embodiment, the valve assembly <NUM> is nested within the anchor assembly <NUM>.

In some embodiments the sheath <NUM> has an outer diameter of about <NUM> Fr (about <NUM>), or about <NUM> Fr (about <NUM>). In some embodiments, the sheath <NUM> has an outer diameter in the range of about <NUM> Fr to about <NUM> Fr (about <NUM> to about <NUM>). In some embodiments, the sheath <NUM> has an outer diameter in the range of about <NUM> Fr to about <NUM> Fr (about <NUM> to about <NUM>).

The transcatheter delivery system <NUM> can also include a delivery catheter <NUM>. As described further below, the anchor assembly <NUM> and the valve assembly <NUM> can be attached to the delivery catheter <NUM> using one or more control wires. The delivery catheter <NUM> can thereby control the positioning of the anchor assembly <NUM> and the valve assembly <NUM> relative to the sheath <NUM>. For example, the delivery catheter <NUM> can be pushed distally while the sheath <NUM> is held stationary to make the anchor assembly <NUM> and the valve assembly <NUM> emerge from within the sheath <NUM>. Or, the sheath <NUM> can be pulled proximally while the delivery catheter <NUM> is held stationary to make the anchor assembly <NUM> and the valve assembly <NUM> emerge from within the sheath <NUM>.

The transcatheter delivery system <NUM> can also include an inner catheter <NUM> (also referred to herein as a "pusher catheter <NUM>"). In some implementations, the inner catheter <NUM> is releasably coupled with the hub <NUM> of the anchor assembly <NUM>. For example, a distal end portion of the inner catheter <NUM> can be threadedly coupled with the hub <NUM>. When the nested anchor assembly <NUM> and valve assembly <NUM> are expressed from the sheath <NUM>, the inner catheter <NUM> can be moved (e.g., pushed distally) or held stationary in concert with the delivery catheter <NUM>.

In some embodiments, components of the transcatheter delivery system <NUM> (such as the sheath <NUM>, the delivery catheter <NUM>, and/or the inner catheter <NUM>) can include one or more of the following features. In some embodiments, one or more portions of the components of the transcatheter delivery system <NUM> are steerable (also referred to herein as "deflectable"). Using such steering, the transcatheter delivery system <NUM> can be deflected to navigate the patient's anatomy and/or to be positioned in relation to the patient's anatomy as desired. For example, the sheath <NUM> can be angled within the right atrium <NUM> to navigate the sheath <NUM> from the inferior vena cava <NUM> to the atrial septum. Accordingly, in some embodiments the sheath <NUM> may include at least one deflectable zone. Using a device such as the deployment control system <NUM> (<FIG>) a clinician can controllably deflect the deflection zone of the sheath <NUM> (and/or other components of the transcatheter delivery system <NUM>) as desired. In some embodiments, one or more components of the transcatheter delivery system <NUM> can include one or more portions that have differing properties as compared to other portions of the component. For example, a component such as the sheath <NUM>, the delivery catheter <NUM>, and/or the inner catheter <NUM> may have a portion that has greater flexibility, stiffness, column strength, and/or the like as compared to other portions of that same component.

In some embodiments, the sheath <NUM>, the delivery catheter <NUM>, and/or the inner catheter <NUM> can comprise a tubular polymeric or metallic material. For example, in some embodiments the sheath <NUM>, the delivery catheter <NUM>, and/or the inner catheter <NUM> can be made from polymeric materials such as, but not limited to, polytetrafluoroethylene (PTFE), fluorinated ethylene propylene (FEP), HYTREL®, nylon, PICOFLEX®, PEBAX®, TECOFLEX®, and the like, and combinations thereof. In alternative embodiments, the sheath <NUM>, the delivery catheter <NUM>, and/or the inner catheter <NUM> can be made from metallic materials such as, but not limited to, nitinol, stainless steel, stainless steel alloys, titanium, titanium alloys, and the like, and combinations thereof. In some embodiments, the sheath <NUM>, the delivery catheter <NUM>, and/or the inner catheter <NUM> can be made from combinations of such polymeric and metallic materials (e.g., polymer layers with metal braid, coil reinforcement, stiffening members, and the like, and combinations thereof).

Referring to <FIG>, in some embodiments one or more control wires can be used to releasably couple the anchor assembly <NUM> and the valve assembly <NUM> to the delivery catheter <NUM>. Such control wires can also be used by a clinician to control the radial expansion of the anchor assembly <NUM> and the valve assembly <NUM>-in some optional implementations, to control the radial expansion of the anchor assembly <NUM> independently from the radial expansion of the valve assembly <NUM> during the deployment procedure. For example, when a control wire is slackened (tension is relaxed) the associated anchor assembly <NUM> or valve assembly <NUM> will be allowed to radially self-expand. Conversely, when a control wire is tensioned, the associated anchor assembly <NUM> or valve assembly <NUM> will be radially contracted, compressed, or constrained. The control wires may also be thought of as "lassos" because, like a lasso, the control wires function to circumferentially, radially, or diametrically control/constrain the anchor assembly <NUM> and the valve assembly <NUM>.

Control wires can be releasably coupled around one or more regions of the anchor assembly <NUM> and the valve assembly <NUM>. For example, control wires can be coupled to a proximal end region, one or more mid-body regions, and/or a distal end region of the anchor assembly <NUM> and/or the valve assembly <NUM>. In some cases, a single control wire can be coupled to both the anchor assembly <NUM> and the valve assembly <NUM>. In one such example, a single control wire can be coupled to the proximal end regions of both the anchor assembly <NUM> and the valve assembly <NUM>. Tensioning the single control wire that is coupled to the proximal end regions of both the anchor assembly <NUM> and the valve assembly <NUM> will cause the proximal end regions of both the anchor assembly <NUM> and the valve assembly <NUM> to be concurrently radially contracted and constrained. Releasing tension from the single control wire that is coupled to the proximal end regions of both the anchor assembly <NUM> and the valve assembly <NUM> will allow the proximal end regions of both the anchor assembly <NUM> and the valve assembly <NUM> to concurrently radially expand.

In some cases, a single control wire is coupled to only one of either the anchor assembly <NUM> or the valve assembly <NUM>. In some such cases, a first control wire can be coupled to one region of either the anchor assembly <NUM> or the valve assembly <NUM>, and a second control wire can be coupled to another region of same anchor assembly <NUM> or valve assembly <NUM>.

In the depicted embodiment, the anchor assembly <NUM> is configured to be releasably coupled with a proximal end region control wire at one or more anchor assembly proximal end coupling sites <NUM>. In addition, the anchor assembly <NUM> is configured to be releasably coupled with a mid-body region control wire at one or more anchor assembly mid-body coupling sites <NUM>.

In the depicted embodiment, the valve assembly <NUM> is configured to be releasably coupled with a proximal end region control wire at one or more valve assembly proximal end coupling sites <NUM>. In addition, the valve assembly <NUM> is configured to be releasably coupled with a distal end region control wire at one or more valve assembly distal end coupling sites <NUM>.

The control wire coupling sites (e.g., the anchor assembly proximal end coupling sites <NUM>, the anchor assembly mid-body coupling sites <NUM>, the valve assembly proximal end coupling sites <NUM>, and the valve assembly distal end coupling sites <NUM>) can be various types of structures to which a wire can be releasably coupled. For example, in some embodiments the control wire coupling sites can be a loop of suture material, two loops of suture material, or three or more loops of suture material. In some embodiments, the control wire coupling sites can be a structure defining an eyelet formed by, or attached to, the framework of the anchor assembly <NUM> and/or the valve assembly <NUM>. In some embodiments, the control wire coupling sites can be cells or struts of the framework of the anchor assembly <NUM> and/or the valve assembly <NUM>. Other types of suitable control wire coupling sites can also be used.

Referring to <FIG>, one or more control wires can releasably couple the valve assembly <NUM> to the delivery catheter <NUM> (for enhanced clarity, the control wires coupling the anchor assembly <NUM> to the delivery catheter <NUM> are not shown). In the depicted embodiment, the valve assembly <NUM> is coupled to the delivery catheter <NUM> by: (i) a valve assembly proximal end control wire <NUM> and (ii) a valve assembly distal end control wire <NUM>. The valve assembly proximal end control wire <NUM> can be releasably coupled with the valve assembly proximal end coupling sites <NUM>. The valve assembly distal end control wire <NUM> can be releasably coupled with the valve assembly distal end coupling sites <NUM>.

Referring to <FIG>, one or more control wires can releasably couple the anchor assembly <NUM> to the delivery catheter <NUM> (for enhanced clarity, the control wires coupling the valve assembly <NUM> to the delivery catheter <NUM> are not shown). In the depicted embodiment, the anchor assembly <NUM> is coupled to the delivery catheter <NUM> by: (i) an anchor assembly proximal end control wire <NUM> and (ii) an anchor assembly mid-body control wire <NUM>. The anchor assembly proximal end control wire <NUM> can be releasably coupled with the anchor assembly proximal end coupling sites <NUM>. The anchor assembly mid-body control wire <NUM> can be releasably coupled with the anchor assembly mid-body coupling sites <NUM>.

Referring to <FIG>, all four of the aforementioned control wires (the valve assembly proximal end control wire <NUM>, the valve assembly distal end control wire <NUM>, the anchor assembly proximal end control wire <NUM>, and the anchor assembly mid-body control wire <NUM>) are now depicted.

In some implementations, fewer than four control wires are included. For example, in some implementations the anchor assembly mid-body control wire <NUM> is not included (but the valve assembly proximal end control wire <NUM>, the valve assembly distal end control wire <NUM>, and the anchor assembly proximal end control wire <NUM>), for a total of three control wires. In another example, the proximal ends of the anchor assembly <NUM> and the valve assembly <NUM> can share a single control wire, and the valve assembly distal end control wire <NUM> can be also used, for a total of two control wires. In another example, the proximal ends of the anchor assembly <NUM> and the valve assembly <NUM> can share a single control wire, and the valve assembly distal end control wire <NUM> and the anchor assembly mid-body control wire <NUM> can be also used, for a total of three control wires.

In some implementations, a deployment control handle/system (such as the deployment frame system <NUM> of <FIG>) is used to control the movements of the control wires, and by extension, the movements of the corresponding anchor assembly <NUM> or valve assembly <NUM> to which the control wires are coupled. For example, the tension of the control wires can be increased or decreased to thereby allow radial self-expansion, or to thereby cause radial contraction/constriction, of the corresponding anchor assembly <NUM> or valve assembly <NUM>.

In some embodiments, the control wires extend through lumens defined in the wall of a catheter, such as the delivery catheter <NUM>. The control wires can extend from such lumens through luminal orifices at the end of the catheter, or at non-end luminal orifice locations along the catheter. For example, in the depicted embodiment, the valve assembly distal end control wire <NUM> extends from luminal orifices at the end of the delivery catheter <NUM>. However, the valve assembly proximal end control wire <NUM>, the anchor assembly proximal end control wire <NUM>, and the anchor assembly mid-body control wire <NUM> each extend from non-end luminal orifices located along the delivery catheter <NUM>.

In some embodiments, such as the depicted embodiment, individual control wires form a loop at the end of the catheter (e.g., the delivery catheter <NUM>). That is, the control wire exits from a first luminal orifice of the catheter, then loops through one or more attachment sites of the anchor assembly <NUM> and/or the valve assembly <NUM>, then reenters a second luminal orifice of the catheter. Portions of the control wire are slidably positioned within lumens within the wall of the catheter. The two terminal ends of the control wire can be positioned at the user control mechanism (e.g., the deployment frame system <NUM> of <FIG>). To remove a control wire from engagement with the anchor assembly <NUM> and/or the valve assembly <NUM>, a clinician can simply pull on one end of the control wire while allowing the second end of the control wire to freely pass into the catheter wall lumen. As the clinician continues to pull, the entire control wire can be removed from engagement with the anchor assembly <NUM> and/or the valve assembly <NUM>, and even from within the lumens of the catheter (if so desired).

While the depicted example includes four control wires (e.g., the valve assembly proximal end control wire <NUM>, the valve assembly distal end control wire <NUM>, the anchor assembly proximal end control wire <NUM>, and the anchor assembly mid-body control wire <NUM>) in some embodiments fewer than four or more than four control wires can be used in conjunction with the depicted nested arrangement of the anchor assembly <NUM> and valve assembly <NUM>. For example, in some embodiments exactly three control wires are included to couple the nested anchor assembly <NUM> and valve assembly <NUM> to the delivery catheter <NUM>. In a first example using three control wires, a first control wire can be releasably coupled with a proximal end region of the valve assembly <NUM>, a second control wire can be releasably coupled with a distal end region of the valve assembly <NUM>, and a third control wire can be releasably coupled with a proximal end region of the anchor assembly <NUM>. In such a case, the relative positioning of the inner catheter <NUM> (coupled to the hub <NUM>) compared to the delivery catheter <NUM> can be adjusted to provide some control of the expansion of the mid-body of the anchor assembly <NUM>. For example, extending the inner catheter <NUM> further distally in comparison to the delivery catheter <NUM> can cause a radial contraction of the mid-body region of the anchor assembly <NUM>. Conversely, pulling the inner catheter <NUM> further proximally in comparison to the delivery catheter <NUM> can cause or allow a radial expansion of the mid-body region of the anchor assembly <NUM>. In a second example using three control wires, a first control wire can be releasably coupled with a distal end region of the valve assembly <NUM>, a second control wire can be releasably coupled with a mid-body region of the anchor assembly <NUM>, and a third control wire can be releasably coupled with the proximal end regions of both of the anchor assembly <NUM> and the valve assembly <NUM>. That is, a single control wire can be releasably coupled with the proximal end region of the anchor assembly <NUM> and also with the proximal end region of the valve assembly <NUM>.

While the depicted example includes four control wires (e.g., the valve assembly proximal end control wire <NUM>, the valve assembly distal end control wire <NUM>, the anchor assembly proximal end control wire <NUM>, and the anchor assembly mid-body control wire <NUM>), in some embodiments, exactly two control wires are included to couple the nested anchor assembly <NUM> and valve assembly <NUM> to the delivery catheter <NUM>. In one such example, a first control wire can be releasably coupled with a distal end region of the valve assembly <NUM>, and a second control wire can be releasably coupled with the proximal end regions of both of the anchor assembly <NUM> and the valve assembly <NUM>. That is, a single control wire can be releasably coupled with the proximal end region of the anchor assembly <NUM> and also with the proximal end region of the valve assembly <NUM>.

<FIG> schematically depict an example serial process for deploying the anchor assembly <NUM> in a native heart valve <NUM> while the anchor assembly <NUM> and the valve assembly <NUM> (collectively the two-part prosthetic mitral valve <NUM>; <FIG> and <FIG>) are positioned relative to each other in the nested arrangement. <FIG> schematically depict an example serial process for deploying the valve assembly <NUM> in the native heart valve <NUM> while the anchor assembly <NUM> and the valve assembly <NUM> are positioned relative to each other in the nested arrangement. It should be understood that retrieval of the anchor assembly <NUM> and/or the valve assembly <NUM> can be readily performed at any time during the depicted sequential procedures as long as at least one of the control wires remain coupled to the valve assembly <NUM>.

As described elsewhere herein, while the depicted implementation includes four control wires, in some implementations a total of three control wires or a total of two control are included. For those implementations that include a single control wire that is shared by the proximal ends of the anchor assembly <NUM> and the valve assembly <NUM>, retrieval can be performed, for example, using the following procedure. The anchor assembly mid-body control wire <NUM> can be released and/or removed from engagement with the anchor assembly <NUM>. Then, the valve assembly distal end control wire <NUM> can be tensioned to collapse the distal end of the valve assembly <NUM>. Next, the single control wire that is shared by the proximal ends of the anchor assembly <NUM> and the valve assembly <NUM> can be tensioned to collapse the proximal end of the valve assembly <NUM> such that retrieval features (e.g., hooks, clips, slots, etc.) on the delivery catheter <NUM> become engaged with the framework of the valve assembly <NUM>. Then, the single control wire that is shared by the proximal ends of the anchor assembly <NUM> and the valve assembly <NUM> can be released/removed to decouple the collapsed valve assembly <NUM> from the anchor assembly <NUM> (while the proximal end of the valve assembly <NUM> remains engaged with the delivery catheter <NUM> by virtue of the proximally-located retrieval features and valve assembly distal end control wire <NUM>). Next, the valve assembly <NUM> can be retracted into sheath <NUM> (e.g., by pulling the delivery catheter <NUM> proximally in relation to the sheath <NUM>). The retrieval features on the delivery catheter <NUM> (with which the valve assembly <NUM> are engaged) and the tensioned valve assembly distal end control wire <NUM> facilitate the insertion of the valve assembly <NUM> (along with the delivery catheter <NUM>) into the sheath <NUM>. Finally, the anchor assembly <NUM> can be positioned within the sheath <NUM> by pulling the inner catheter <NUM> (to which the hub <NUM> is coupled) into the sheath <NUM>. The anchor assembly <NUM> may evert as it is pulled into the sheath <NUM>.

Referring to <FIG>, as described above the transcatheter delivery system <NUM> can be been used to intravascularly navigate the two-part prosthetic mitral valve <NUM> to the left atrium <NUM>. The anchor assembly <NUM> and the valve assembly <NUM> (positioned relative to each other in the nested arrangement as shown) can be simultaneously expressed from the sheath <NUM> while in the left atrium <NUM>. In some implementations, it is desirable to orient (e.g., laterally pivot, pan, steer, etc.) the nested anchor assembly <NUM> and valve assembly <NUM> within the atrium <NUM> so that their longitudinal axes are generally perpendicular to the native mitral valve <NUM>, and coaxial with the native mitral valve <NUM> (e.g., to center the nested anchor assembly <NUM> with the line of coaptation of the mitral valve <NUM>). Such orienting of the partially or fully expanded nested anchor assembly <NUM> and valve assembly <NUM> within the atrium <NUM> may be advantageous versus having to orient them while they are still constrained within the delivery sheath <NUM>, as the latter assembly can be a relatively large and stiff catheter assembly.

After the nested anchor assembly <NUM> and valve assembly <NUM> is expressed from the sheath <NUM> in the left atrium <NUM>, a clinician can relax some tension from the anchor assembly mid-body control wire <NUM> to allow the anchor assembly <NUM> to partially expand. For example, in some cases the mid-body region of the anchor assembly <NUM> may be allowed to expand about <NUM>% of its fully expanded radial size. Accordingly, the anchor feet 220a, 220b, 220c, and 220d (<FIG>) expand radially outward. Such expansion can be performed in preparation for seating the anchor feet 220a, 220b, 220c, and 220d within the sub-annular gutter <NUM> of the native mitral valve <NUM>. At this stage, the other control wires (e.g., the valve assembly proximal end control wire <NUM>, the valve assembly distal end control wire <NUM>, and the anchor assembly proximal end control wire <NUM>) can remain fully tensioned such that the proximal end region of the anchor assembly <NUM> and the entirety of the valve assembly <NUM> remain radially contracted.

With the mid-body region of the anchor assembly <NUM> partially expanded, the nested anchor assembly <NUM> and valve assembly <NUM> can be pushed distally as indicated by arrow <NUM>. The anchor feet 220a, 220b, 220c, and 220d may physically help to proper align the anchor assembly <NUM> to the native mitral valve <NUM> as the anchor assembly <NUM> is partially pushed through the annulus of the native mitral valve <NUM>. The distal portions of the nested anchor assembly <NUM> and valve assembly <NUM> will pass through the annulus of the mitral valve <NUM> and into the left ventricle <NUM> as shown. With the anchor assembly <NUM> partially radially contracted in a desired orientation, and appropriately aligned with the mitral valve <NUM>, the anchor assembly <NUM> can be safely passed through the native mitral valve <NUM> without damaging the native mitral valve <NUM> and/or entangling chordae tendineae of the mitral valve <NUM>.

Referring to <FIG>, further distal movement of the nested anchor assembly <NUM> and valve assembly <NUM> will cause the anchor feet 220a, 220b, 220c, and 220d (<FIG>) to pass through the annulus of the native mitral valve <NUM> and into the left ventricle <NUM>. Then, the clinician can fully relax (or nearly fully relax) the tension from the anchor assembly mid-body control wire <NUM> to allow the mid-body region of the anchor assembly <NUM> to fully expand (or nearly fully expand). Accordingly, the anchor feet 220a, 220b, 220c, and 220d can be then properly seated within the sub-annular gutter <NUM> of the native mitral valve <NUM>.

The regions at or near the high collagen annular trigones of the sub-annular gutter <NUM> can generally be relied upon to provide strong, stable anchoring locations. The muscle tissue in the regions at or near the trigones also provides a good tissue ingrowth substrate for added stability and migration resistance of the anchor assembly <NUM>. Therefore, the regions at or near the trigones define a left anterior anchor zone and a right anterior anchor zone. The left anterior anchor zone and the right anterior anchor zone provide advantageous target locations for placement of the lateral anterior foot 220a and the medial anterior foot 220d respectively. The left posterior anchor zone and the right anterior anchor zone of the sub-annular gutter <NUM> can receive the lateral posterior foot 220b and the medial posterior foot 220c respectively.

Referring to <FIG>, as a next step of the process for implanting the two-part prosthetic mitral valve <NUM> arranged in the nested configuration, the clinician can relax the anchor assembly proximal end control wire <NUM>. Doing so will allow the proximal end of the anchor assembly <NUM>, including the supra-annular structures of the anchor assembly <NUM>, to self-expand. For example (referring also to <FIG>), relaxing the tension on the anchor assembly proximal end control wire <NUM> will allow radial expansion of the atrial holding features 240a, 240b, and 240c. The atrial holding features 240a, 240b, and 240c are configured to contact the shelf-like supra-annular tissue surface above the annulus of the mitral valve <NUM>, and to thereby stabilize the anchor assembly <NUM> in supra-annular areas while providing resistance against migration in the direction towards the left ventricle <NUM>. Relaxing the tension on the anchor assembly proximal end control wire <NUM> will also allow radial expansion of the lateral anterior anchor arch 250a, the posterior anchor arch 250b, and the medial anterior anchor arch 250c. The lateral anterior anchor arch 250a, the posterior anchor arch 250b, and the medial anterior anchor arch 250c are joined with each other to form the undulating supra-annular ring <NUM> that acts as a supra-annular structural element for the anchor assembly <NUM>.

With the tensions from the anchor assembly proximal end control wire <NUM> and the anchor assembly mid-body control wire <NUM> removed, the anchor assembly <NUM> is fully expanded and engaged with the native mitral valve <NUM>. Thereafter, the clinician can remove the anchor assembly proximal end control wire <NUM> and the anchor assembly mid-body control wire <NUM> from engagement with the anchor assembly <NUM> if so desired. To do so, the clinician can simply pull on a first end of the control wire <NUM> and/or <NUM> while the second end of the control wire <NUM> and/or <NUM> is free to move.

Referring to <FIG>, after a sufficient amount of pulling the control wires <NUM> and/or <NUM> by the clinician, the control wire <NUM> and/or <NUM> will become disengaged from the anchor assembly <NUM> as shown. In result, the anchor assembly <NUM> is fully expanded and engaged with the anatomical structure of the native mitral valve <NUM>. At this stage, the inner catheter <NUM> can continue to be coupled with the hub <NUM> of the anchor assembly <NUM>. Therefore, retrieval of the anchor assembly <NUM> is still possible even though the control wires <NUM> and <NUM> have been removed from engagement with the anchor assembly <NUM>.

<FIG> illustrates the same arrangement as in <FIG>, but in a less schematic fashion. For example, the still radially-constrained valve assembly <NUM> is shown within the expanded anchor assembly <NUM> that is engaged with the native mitral valve <NUM>. This commissural cross-sectional view of the heart <NUM> is a cross-sectional view taken through the mitral valve <NUM> along a plane through the left atrium <NUM> and left ventricle <NUM> that is parallel to the line that intersects the two commissures of the mitral valve <NUM>. The view is slightly tilted so that better visualization of the two-part prosthetic mitral valve <NUM> is provided.

The supra-annular structures of the anchor assembly <NUM> are radially expanded (e.g., the atrial holding features 240a, 240b, and 240c, and the anchor arches 250a, 250b, and 250c). The atrial holding features 240a, 240b, and 240c are in contact with or adjacent to the shelf-like supra-annular tissue surface above the annulus of the mitral valve <NUM>. The lateral anterior anchor arch 250a, the posterior anchor arch 250b, and the medial anterior anchor arch 250c are expanded to form the undulating supra-annular ring <NUM> that acts as a supra-annular structural element for the anchor assembly <NUM>.

The sub-annular structures of the anchor assembly <NUM> are also radially expanded (e.g., the anchor feet 220a, 220b, 220c, and 220d). In this arrangement, the anchor feet 220a, 220b, 220c, and 220d are properly seated within the sub-annular gutter <NUM> of the native mitral valve <NUM>.

Referring to <FIG>, a schematic depiction of the two-part prosthetic mitral valve <NUM> arranged in the nested configuration can once again be used to describe the remaining steps of the deployment process. The anchor assembly <NUM> is already deployed at this stage (other than the continued releasable coupling of the inner catheter <NUM> to the hub <NUM> of the anchor assembly <NUM>).

To allow the valve assembly <NUM> to radially expand while being nested within the anchor assembly <NUM>, the tensions of the valve assembly proximal end control wire <NUM> and the valve assembly distal end control wire <NUM> can be relaxed. Relaxing tension from the valve assembly proximal end control wire <NUM> and the valve assembly distal end control wire <NUM> allow the valve assembly <NUM> to self-expand and to couple with the anchor assembly <NUM>.

In some cases, the tensions of the valve assembly proximal end control wire <NUM> and the valve assembly distal end control wire <NUM> can be relaxed simultaneously. In some cases, the tensions of the valve assembly proximal end control wire <NUM> and the valve assembly distal end control wire <NUM> can be relaxed serially (including any and all possible patterns of altemating, step-wise, and partial relaxations of the tensions).

When the valve assembly <NUM> and the anchor assembly <NUM> are coupled together, the valve assembly <NUM> is geometrically interlocked within the interior space of the anchor assembly <NUM> (e.g., in some embodiments by virtue of the tapered shape of the valve assembly <NUM> within the supra-annular ring and interior space of the anchor assembly <NUM>). In particular, in some embodiments the valve assembly <NUM> is contained within the interior space between the supra-annular ring <NUM> and the sub-annular support arms 230a, 230b, 230c, and 230d (refer to <FIG>).

Referring also to <FIG>, the next step of the process for deploying the two-part prosthetic mitral valve <NUM> arranged in the nested configuration can include removal of the valve assembly proximal end control wire <NUM> from engagement with the valve assembly proximal end coupling sites <NUM>, and removal of the valve assembly distal end control wire <NUM> from engagement with the valve assembly distal end coupling sites <NUM>. The removals of the valve assembly proximal end control wire <NUM> and the valve assembly distal end control wire <NUM> can be performed as described above in reference to the anchor assembly proximal end control wire <NUM> and the anchor assembly mid-body control wire <NUM>.

After the valve assembly <NUM> has been expanded into a coupled relationship with the anchor assembly <NUM>, the clinician can verify that the anchor assembly <NUM> and the valve assembly <NUM> are in the desired positions. Additionally, the clinician may verify other aspects such as, but not limited to, the hemodynamic performance and sealing of the anchor assembly <NUM> and the valve assembly <NUM>.

The anchor assembly <NUM> and the valve assembly <NUM> are deployed at this stage (other than the continued releasable coupling of the inner catheter <NUM> to the hub <NUM> of the anchor assembly <NUM>).

Referring also to <FIG>, the process of deploying the two-part prosthetic mitral valve <NUM> arranged in the nested configuration can be completed by disengaging the inner catheter <NUM> from the hub <NUM> of the anchor assembly <NUM>, and removing the delivery system <NUM> from the patient. The SAM containment member <NUM> (<FIG>) may also be deployed as a result of this step. The two-part prosthetic mitral valve <NUM> engaged with the native mitral valve <NUM> is thereafter able to take over the performance the native mitral valve function.

While the components of the delivery system <NUM> and the two-part prosthetic mitral valve <NUM> are depicted in particular relative orientations and arrangements, it should be understood that the depictions are non-limiting.

Claim 1:
A transcatheter mitral valve replacement system for a heart (<NUM>), comprising:
a delivery sheath (<NUM>) having a distal end portion insertable into a left atrium;
a delivery catheter (<NUM>) slidably disposed within the delivery sheath (<NUM>); and
a two-part prosthetic mitral valve (<NUM>) coupled to the delivery catheter (<NUM>) by one or more control wires, the two-part prosthetic mitral valve (<NUM>) configured to be disposed within the delivery sheath (<NUM>) in a radially compressed condition and to radially self-expand when the two-part prosthetic mitral valve (<NUM>) is outside of the delivery sheath (<NUM>) and is unconstrained by the one or more control wires, the two-part prosthetic mitral valve (<NUM>) comprising:
a valve assembly (<NUM>) including an expandable valve frame and a tri-leaflet occluder;
an anchor assembly (<NUM>) separately expandable from the valve assembly (<NUM>) and defining an interior space within which the valve assembly (<NUM>) is nested while the two-part prosthetic mitral valve (<NUM>) is within the delivery sheath (<NUM>) for simultaneous deployment from the delivery sheath (<NUM>); and
a pusher catheter (<NUM>) slidably disposed within the delivery catheter (<NUM>) and releasably coupled to the anchor assembly (<NUM>).