WO2012142189A1

WO2012142189A1 - Prostheses, systems and methods for percutaneous heart valve replacement

Info

Publication number: WO2012142189A1
Application number: PCT/US2012/033162
Authority: WO
Inventors: Tung Hoang NGO
Original assignee: Skardia, Llc
Priority date: 2011-04-11
Filing date: 2012-04-11
Publication date: 2012-10-18

Abstract

A prostheses for percutaneous heart valve replacement including a stent assembly selectively expandable to an operative position in which the stent assembly is positioned in compressive contact with at least a portion of an interior surface of the native valve annulus; a frame assembly, operatively coupled to a portion of the stent assembly, and that is selectively expandable and that defines a plurality of common upwardly extending commissural posts and a plurality of downwardly extending wing members that at least partially overlie a portion of an exterior surface of the stent assembly; and a biocompatible covering coupled to a portion of the frame assembly and extending to a peripheral edge of the wing members to thereby define a plurality of covered wing members, an upper portion of the biocompatible covering being coupled to a portion of the commissural posts to form an operative valve having a plurality of leaflets.

Description

PROSTHESES, SYSTEMS AND METHODS FOR PERCUTANEOUS HEART VALVE REPLACEMENT

BACKGROUND OF THE INVENTION

Field of the Invention

[0001] This invention relates generally to prostheses, systems and methods for percutaneous heart valve replacement.

Description of the Related Art

[0002] Aortic stenosis is one of the most common valvular disorders in aging populations. Open surgical aortic valve replacement (SAVR) is the conventional treatment modality used to improve valve function, symptoms and longevity of patients. However, as many as a third of all patients who suffer from aortic stenosis or other insufficiency are contraindicated for SAVR due to co-morbid conditions or other risk factors.

[0003] Percutaneous heart valve replacement (PHVR) is an emerging alternative to SAVR. Currently, PHVR is indicated only for patients exhibiting too great a risk to be considered viable candidates for SAVR. PHVR is performed via catheter-based or transcatheter techniques on a beating heart, eliminating the need for cardiopulmonary bypass and avoiding the more invasive open heart surgical techniques. In PHVR, a replacement heart valve is delivered via a catheter to and placed across the native aortic valve. Typical current commercial embodiments of percutaneous heart valve prostheses have a replacement valve supported by a metal stent structure. The metal stent structure is expanded to secure the entire prosthesis and push the calcified native valve aside, leaving the native valve leaflets exposed to the circulatory system.

[0004] PHVR using current commercial embodiments of percutaneous heart valve prostheses involve risks of serious adverse events such as peripheral vascular complications; prosthesis malfunction, misplacement or migration; injury to surrounding tissues and structures (e.g., the myocardium); significant arrhythmia; cerebrovascular events (e.g., embolism, stroke); myocardial infarction; and hemodynamic collapse. In some cases, these adverse events result in the need for further intervention, e.g., a pacemaker to overcome conduction blockage created by the prosthesis, or death. Thus, there is a need for improved percutaneous heart valve prostheses, systems and methods.

SUMMARY

[0005] A prostheses, apparatus, system and method for percutaneous heart valve replacement is disclosed herein. In one aspect, the apparatus can comprise a stent assembly, a coupled frame assembly, and a biocompatible covering. The stent assembly can be configured to be selectively expandable to an operative position, in which the stent assembly has an expanded outside diameter that can be is positioned in compressive contact with at least a portion of an interior surface of the native valve annulus.

[0006] In a further aspect, the frame assembly can be operatively coupled to a portion of the stent assembly. In one aspect, the frame assembly can be configured to be selectively expandable to an operative position, in which the frame assembly has an expanded outside diameter. In one aspect, the frame assembly can comprise a plurality of at least partially arcuate rib members that can be configured or otherwise positioned adjacent to each other such that the first end of one rib member is positioned adjacent to the second end of an adjacent rib member. In a further aspect, upper portions of the respective adjacent rib members can define a plurality of common upwardly expending commissural posts and lower portions of the respective rib members can define a plurality of downwardly extending wing members that at least partially overlies portions of an exterior surface of the stent assembly.

[0007] The biocompatible covering can be coupled to at least portions of the common commissural posts and can extend downwardly to a peripheral edge of the respective wing members to thereby define a plurality of coyered wing members. Portions of the an upper portion of the biocompatible covering is coupled or otherwise attached to a top portion of the commissural posts to form an operative valve having a plurality of leaflets that are configured to operatively open and close the opening defined at a distal end of the formed valve.

[0008] The system can further comprise a guidewire and an elongate assembly that is suitably configured to be disposed within a bodily lumen and to selectively deliver the prostheses and or apparatus into position within the subject. In one aspect, the elongate assembly can comprise a first shaft and a second shaft. In this aspect, the first shaft can define a central lumen for receiving the guidewire and the second shaft can define a central lumen for receiving the first shaft and both the stent assembly and the frame assembly in their respective delivery positions. In operation a portion of the first shaft is configured to be movably disposed within the central lumen of the second shaft. In another aspect, each of the respective first and second shafts can be configured to be selectively and independently bi- axially movable relative to and about the guidewire.

[0009] Additional advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The advantages of the invention will be realized and attained by means of the elements and combinations particularly pointed out in the appended claims. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments and together with the description, serve to explain the principles of the methods and systems:

[0011] Figure 1 is a schematic showing a cross-sectional view of an exemplary prothesis comprising a suprannular assembly and a stent assembly that are directly connected to one another, all in an operative configuration.

[0012] Figure 2 is a schematic showing a cross-sectional view of an exemplary prothesis (without the biocompatible covering) comprising a frame assembly and a stent assembly that are not directly connected to one another, all in an operative configuration.

[0013] Figure 3 is a schematic showing one example of a frame assembly and a stent assembly formed from one continuous piece of material.

[0014] Figure 4 is a schematic showing one example of a portion of an unextended prosthesis that has been formed by cutting one continuous piece of material.

[0015] Figure 5 is a schematic showing a deployed prosthesis that comprises a stent assembly, and a suprannular assembly.

[0016] Figure 6 is a schematic showing one example of a prosthesis having both a stent assembly and a distal anchor assembly configured as a stent.

[0017] Figure 7 is a schematic showing one example of a suprannular assembly and a distal anchor configured as extensions from the apex of the commissure posts. [0018] Figure 8 is a schematic showing one example of a trans femoral delivery system comprising an elongate assembly further comprising a guidewire, a first shaft, and a second shaft, where the delivery system is positioned and deploying the suprannular assembly immediately superior to the aortic valve, the second sheath having being retracted proximally relative to a delivery position.

[0019] Figure 9 is a schematic showing the transfemoral delivery system of Figure 10 where the suprannular assembly is in an operative position and stent assembly remains in a delivery position.

[0020] Figure 10 is a schematic showing the transfemoral delivery system of Figure 10 where both the suprannular assembly and stent assembly are in an operative position.

[0021] Figure 1 1 is a schematic showing the transfemoral delivery system of Figure 10 where both the suprannular assembly and stent assembly are in an operative position and the first and second shafts, atraumatic tip and guidewire are removed proximally from the patient.

[0022] Figure 12 is a schematic showing one example of a transapical delivery system comprising an elongate assembly that further comprises a first shaft, a pusher assembly, a second shaft and a prosthesis, all in a delivery position.

[0023] Figure 13 is a schematic showing the transapical delivery system of Figure 12, where the second shaft has been moved proximally relative to the first shaft to expose the frame assembly and allow it to deploy in an umbrella-like fashion to an operative position.

[0024] Figure 14 is a schematic showing the transapical delivery system of Figure 12, second shaft has been moved further proximally relative to the first shaft to expose the stent assembly and allow it to deploy while the pusher assembly still engages the prosthesis.

[0025] Figure 15 is a schematic showing the transapical delivery system of Figure 12, where both the frame assembly and stent assembly are retracted back into the delivery system.

[0026] Figure 16 is a schematic showing the transapical delivery system of Figure 12, where the frame assembly and stent assembly have both been released by the pusher assembly. [0027] Figure 17 is a schematic showing one example of a transapical delivery system comprising an elongate assembly that further comprises a first shaft, a pusher assembly, a distal sheath housing a suprannular assembly, and a proximal sheath housing the stent assembly, all in a delivery position.

[0028] Figure 18 is a schematic showing the transapical delivery system of Figure 17, where the distal sheath and first shaft have been advanced distally to allow the suprannular assembly to deploy in an umbrella-like fashion to an operative position.

[0029] Figure 19 is a schematic showing the transapical delivery system of Figure 17, where the proximal sheath has been moved proximally to allow the stent assembly to deploy to an operative position.

[0030] Figure 20 is a schematic showing the transapical delivery system of Figure 17, illustrating how the proximal sheath can be advanced distally to recapture the stent assembly and the frame assembly after deployment.

[0031] Figure 21 is a schematic showing the transapical delivery system of Figure 17, illustrating a deployed suprannular assembly and stent assembly being released from the pusher assembly.

DETAILED DESCRIPTION

[0032] Before the present methods and systems are disclosed and described, it is to be understood that the methods and systems are not limited to specific synthetic methods, specific components, or to particular compositions. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting.

[0033] As used in the specification and the appended claims, the singular forms "a," "an" and "the" include plural referents unless the context clearly dictates otherwise. Ranges may be expressed herein as from "about" one particular value, and/or to "about" another particular value. When such a range is expressed, another embodiment includes from the one particular value and/or to the other particular value. Similarly, when values are expressed as approximations, by use of the antecedent "about," it will be understood that the particular value forms another embodiment. It will be further understood that the endpoints of each of the ranges are significant both in relation to the other endpoint, and independently of the other endpoint. [0034] "Optional" or "optionally" means that the subsequently described event or circumstance may or may not occur, and that the description includes instances where said event or circumstance occurs and instances where it does not.

[0035] Throughout the description and claims of this specification, the word "comprise" and variations of the word, such as "comprising" and "comprises," means "including but not limited to," and is not intended to exclude, for example, other additives, components, integers or steps. "Exemplary" means "an example of and is not intended to convey an indication of a preferred or ideal embodiment. "Such as" is not used in a restrictive sense, but for explanatory purposes.

[0036] Disclosed are components that can be used to perform the disclosed methods and systems. These and other components are disclosed herein, and it is understood that when combinations, subsets, interactions, groups, etc. of these components are disclosed that while specific reference of each various individual and collective combinations and permutation of these may not be explicitly disclosed, each is specifically contemplated and described herein, for all methods and systems. This applies to all aspects of this application including, but not limited to, steps in disclosed methods. Thus, if there are a variety of additional steps that can be performed it is understood that each of these additional steps can be performed with any specific embodiment or combination of embodiments of the disclosed methods.

[0037] The present methods and systems may be understood more readily by reference to the following detailed description of preferred embodiments and the Examples included therein and to the Figures and their previous and following description.

[0038] Embodiments provided herein comprise prostheses, systems and methods for percutaneous heart valve replacement. The exemplary embodiments disclosed herein relate to prostheses, systems and methods for treating particular disorders such as aortic stenosis and insufficiency. However, it should be understood that describing use of the prostheses, systems and methods with respect to any particular disorder or disease is emblematic of other embodiments of the invention suited to other disorders or diseases, e.g., mitral stenosis, mistral regurgitation, tricuspid and pulmonic valve disorders, and venous insufficiency, and should not be construed as limiting the scope of this disclosure.

[0039] Referring generally to Figures 1 and 2, in one aspect, the prosthesis 100 comprises at least one of: a suprannular assembly 102 and a stent assembly 104. The suprannular assembly 102 further comprises a valve 106, a plurality of downwardly extending covered wing members 108, a frame assembly 110 and a first biocompatible covering 112. Figure 1 depicts the prosthesis 100 with a first biocompatible covering 112 and Figure 2 depicts the prosthesis 100 absent the biocompatible covering 112. In one aspect, the stent assembly 104, in an operative position, is positioned in compressive contact with at least a portion of the native valve annulus. In one exemplary aspect, in an operative position, the suprannular assembly 102 is located entirely on the outflow side of the diseased native valve, has a maximum diameter past which further expansion is resisted, and at least partially overlies an exterior surface of the stent assembly 104 located within the native annulus. It is contemplated that the stent assembly 104, can create compressive contact with the native valve annulus and, optionally, can create additional compressive contact with the peripheral edge of the wing members 108 of suprannular assembly 102, to secure the prosthesis 100 in place and to substantially seal the prosthesis 100 against paravalvular leakage. In another aspect, the stent assembly 104 and suprannular assembly 102 can be configured to further function to substantially encapsulate the native valve leaflets in order to minimize undesired embolic discharge into the bloodstream from the native valve leaflets.

[0040] In one aspect, the stent assembly 104 can be configured to be selectively movable about and between a delivery position, in which the stent assembly 104 has a reduced outside diameter, and an operative position, where the stent assembly 104 has an expanded outside diameter that is positioned in compressive contact with at least a portion of the annulus of the native valve. In this aspect, the stent assembly 104 can serve to enlarge the native valve annulus and also to push aside the native valve leaflets.

[0041] In one aspect, the frame assembly 110, and i ultimately the suprannular assembly 102, can be configured to be selectively movable between a delivery position, in which the frame assembly 110 has a reduced outside diameter, and a deployed position, where the frame assembly 110 has an expanded outside diameter. In one exemplary aspect shown in Figure 3, the frame assembly 110 can comprise a plurality of at least partially arcuate rib members 114 where each rib member has a first end and an opposed, spaced second end. In this aspect, each of the respective rib members 114 of the plurality of rib members 114 are positioned so that the first end of one rib member is positioned adjacent to the second end of the adjacent rib member. As shown in the figures, it is contemplated that the upper ends of the adjacent rib members 114 can be joined or otherwise positioned to form upwardly extending commissural posts 116. In one aspect, the downwardly extending wing members extend downwardly to that the peripheral e ge of the wing member can at least partially overlie the exterior surface of the stent assembly 104 when they are in their respective deployed positions. In one aspect, the frame assembly 110 can be configured such that the number of rib members 114 is selected to match the number of native valve leaflets and the rib members 114 can be further configured so that the common commissural posts 116 are positioned at approximately the same locatipn as the commissural regions of the native valve.

[0042] In a further aspect, the frame assembly 110 can be configured to accommodate the contours of the distal side of the native aortic valve and surrounding vasculature. In this aspect, the three rib members 114 are configured such that the common commissural posts 116 are positioned at approximately 120 degrees apart. This embodiment of the frame assembly 110 ultimately enables accurate and direct placement of the prosthesis 100 as well as minimizes potential for post-deployment paravalvular leakage.

[0043] In an additional aspect shown in at least Figures 1 and 3, a first biocompatible covering 112 can be coupled to the common commissural posts 116 and can extend downwardly toward the peripheral edge of the at least partially arcuate rib members 114 so that a plurality of spaced, covered wing members 108 is formed. In one aspect, the first biocompatible covering 112 can comprise an upper portion 118 and an adjoining a lower portion 120. In this aspect, the upper portion 118 of the first biocompatible covering 112 can be coupled to the top portions of the commissural posts 116 and can thereby form an operative valve 106 having a plurality of leaflets that operatively open and close a valve opening that is defined at the distal end of the formed operative valve 106. Further, in another aspect, the lower portion 120 of the first biocompatible covering 112 can extend downwardly to the peripheral edge of the wings from a lower terminal edge defined by the upper portion 118 and can form means for oreating a paravalvular seal and means for substantially encapsulating the native valve leaflets to minimize undesired embolic discharge into the bloodstream there from.

[0044] In one aspect depicted in Figure 5, the upper and lower portions of the first biocompatible covering 112 can be formed from the same material or from different materials. Optionally, the upper portion 118 of the biocompatible material can comprise porcine pericardial tissue, bovine pericardial tissue, equine pericardial tissue, genetically grown tissue, polytetraflouroethylene, polyethylene terephthalate, polyurethane,

polyurethane/silicon composites and other suitable materials known in the art. In another optional aspect, suitable materials for the lower portion J 20 of the first biocompatible covering 112 can comprise polytetraflouroethylene, polyethylene terephthalate, polyurethane, polyurethane/silicon composites, genetically grown tissue and other suitable biocompatible materials known in the art. In a further aspect, at least portions of both the upper and lower portions of the first biocompatible covering 112 can be formed from a woven material. It is optionally contemplated that both the upper and lower pprtions of the biocompatible material can be substantially continuously joined to ¾he frame assembly 110 and to each other by suturing or other methods known in the art. In an additional aspect, the first biocompatible covering 112 can further comprise additional material 122 at the proximal side of the base of each common commissural post, which additional material 122 can be folded or convoluted in position. In one aspect, the additional gathered material can be operable to further seal the prosthesis 100 against paravalvular leakage when the suprannular assembly 102 is positioned in the operative position.

[0045] In an optional aspect, a second biocompatible covering 124 can be coupled to at least a portion of the outside of the stent assembly 104 to form a lining operative to enhance the paravalvular seal.

[0046] In another aspect, the stent assembly 104 and at least a portion of the suprannular assembly 102 define an annulus. In this aspect, the upper portion 118 of the first

biocompatible covering 112 comprising the valve 106 is located substantially outside the annulus when both the suprannular assembly 102 and st nt assembly 104 are in either of their respective delivery or operative positions.†his allows the suprannular assembly 102 to achieve a reduced diameter in the delivery position than if the valve 106 were located inside the annulus.

[0047] In another aspect depicted in Figure 6, the prosthesis 100 can further comprise a distal anchor assembly 126 positioned dista| to and connected to the suprannular assembly 102. In this aspect, it is contemplated that the distal anchor assembly 126 can be configured to be selectively movable between a delivery position, in which the distal anchor assembly 126 has a reduced outside diameter, and an operative position, where the distal anchor assembly 126 has an expanded outside diameter that is positioned in contact with at least a portion of the downstream native vessel. In one exemplary aspect, the distal anchor assembly 126 can be configured to be a conventional stent-like structure that can be selectively positioned in compressive contact with the downstream native vessel. It is also contemplated that the distal anchor can further comprise a means for passively creating an interference fit between the distal end of the prosthesis 100 and the inner diameter of the downstream native vessel in order to resist further downstream migration in a narrowing native vessel of the suprannular assembly 102 or the entire prosthesis 100 once placed in an operative position. In one aspect, the means for passively creating the interference fit can comprise extension members 127 extending distally from the distal end of the commissural posts 116. The extension members 127 can, optionally, bias radially outward in the operative position. In various aspects, the extension members 127 can be formed from the same continuous piece of material as the frame assembly 110 or can be formed separately from and joined to the frame assembly 110 at the distal end of the commissural posts 116. In one aspect, the extension members 127 can comprise materials such as shape memory material,

polytetraflouroethylene, polyethylene terephthalate and pther suitable biocompatible materials known in the art. In another aspect, the extension members 128 can also comprise a mesh material. Optionally, the distal anchor assembly 1 6 can be configured to promote endothelialization and tissue ingrowth to further secure the prosthesis 100.

[0048] In one aspect, the frame assembly 110, the stent assembly 104 and the distal anchor assembly 126 can be at least partially formed from shape memory materials so that they are self-expanding from their respective delivery to operative positions. In one aspect, the shape memory material can be selected from the group comprising nitinol, cobalt- chromium, or a polymer. In an alternate aspect, the frame assembly 110, the stent assembly 104 and the distal anchor assembly 126 can be at least partially formed from materials configured to be balloon-expanded from their respective delivery positions to their respective operative positions, such materials being selected from the group comprising stainless steel and cobalt-chromium.

[0049] In a further aspect, both the frame assembly 110, stent assembly 104 and, optionally, distal anchor assembly 126 can further comprise radiopaque markers to facilitate fluoroscopic imaging and placement during delivery.

[0050] In one aspect, the stent assembly 104, the frame assembly 110, and, optionally, the distal anchor assembly 126 can be formed together or at least one of the stent assembly 104, suprannular assembly 102, or distal anchor assembly 126 can be configured to be joined during deployment of the prosthesis 100. As an example, in an embodiment in which the stent assembly 104 and the frame assembly 110 are formed together, the stent assembly 104 and the frame assembly 110 can be optionally be formed from at least one wire element; laser cut from a continuous tube or sheet of material; or fabricated according to other techniques known in the art of stent manufacturing.

[0051] In another example, the stent assembly 104 and the frame assembly 110 can be formed separately and are not directly physically attached during deployment of the prosthesis 100. In this embodiment, the opposing forces between the proximal end of the frame assembly 110 and the stent assembly 104 are suitable to secure the prosthesis 100 and also to substantially prevent paravalvular leakage.

Delivery System and Methods

[0052] Another aspect of the present invention are delivery systems and associated methods for securing the prosthesis 100 in a delivery position, delivering the prosthesis 100 to a delivery site, and deploying the prosthesis 100.

[0053] In one aspect, percutaneous prosthesis deployment is conventionally

accomplished using a catheter having a first shaft 132 defining a central lumen for receiving a guidewire 130, and a second shaft 134 defining a central lumen for receiving the first shaft 132, pusher assembly 136 and the prosthesis 100 in a delivery position. In this aspect, both of the respective first and second shafts, 132 and 134 respectively, are configured to be selectively and independently bi-axially movable relative to and about the guidewire 130. As one skilled in the art will appreciate, selective retraction of the second shaft 134 allows the suprannular assembly 102, stent assembly 104 and distal anchor assembly 126 to selectively open in a predetermined sequence. In any disclosed example, the second shaft 134 has an outside diameter of about 10 mm or less, more preferably of about 5 mm or less, and most preferably of about 3mm or less. The low profile of the second shaft 134 is enabled by the upper portion 118 of the first biocompatible covering 1 12 (i.e., the valve 106) being located substantially outside the annulus formed by at least a portion of the lower region of the prosthesis in a delivery position. At any point during the delivery and deployment process, the user can confirm the proper placement of the suprannular assembly 102 or stent assembly 104 using fluoroscopy (with or without additional radiopaque markers operative to assist a user in accurately placing the prosthesis 100), ultrasound, or other visualization methods.

[0054] One skilled in the art will appreciate that the particular characteristics of the delivery system 128 used to deploy the prosthesis 100 will depend on which native valve is selected as the delivery site. In one aspect, it is contemplated that the prothesis described herein can be utilized with any of the mitral valve, tricuspid valve, aortic valve, pulmonary valve and any peripheral venous valve such as those involved in varicose veins of the legs. With this understanding, examples of the delivery system 128 of the present invention are disclosed that are configured to employ a transfemoral or transapical approach to deliver the prosthesis 100 to an aortic valve. Modifications to these delivery systems to place the prosthesis 100 in any other valve via additional percutaneous methods, e.g., transaortic and subclavian approaches, are contemplated and implicit in this disclosure.

[0055] Figure 8 illustrates a delivery system 128 configured for transfemoral delivery of a prosthesis 100 to an aortic valve. In this exemplary aspect, the delivery system 128 comprises an elongate assembly further comprising a guidewire 130, a first shaft 132 defining a central lumen for receiving a guidewire 130, and a second shaft 134 defining a central lumen for receiving the first shaft 132 and the prosthesis 100 in a delivery position. Both the first and second shafts, 132 and 134 respectively, are configured to be selectively and independently bi-axially movable relative to and about both the guidewire 130 and each other. In one aspect, selective retraction of the second shaft 134 relative to the first shaft 132 allows the suprannular assembly 102, stent assembly 104 and, optionally, distal anchor assembly 126 to deploy selectively in a proper orientation and location and in a

predetermined sequence.

[0056] In one aspect depicted in Figure 8, the delivery system 128 can initially be advanced until the distal end of the implant is positioned superior to a native aortic valve. Subsequently, as depicted in Figures 8 and 9, the second sheath can be retracted to expose and facilitate deployment of the suprannular assembly 102 and, optionally, a distal anchor assembly 126. As depicted in Figure 10, Once the suprannular assembly 102 is positioned and deployed in an operative position, the second shaft 134 is further configured to move proximally to position and deploy the stent assembly 104 within the native valve annulus. Optionally, the stent assembly 104 can either be connected to the suprannular assembly 102 or not in this described exemplary embodiment. In one Aspect, the second shaft 134 can be operable to recapture the at least partially deployed stent assembly 104 and facilitate either repositioning or retrieval of the stent assembly 104 and, optionally, the deployed suprannular assembly 102, when the second shaft 134 is advanced distally relative to the first shaft 132. Then, as depicted in Figure 11, the delivery system 128 is removed from the body. In various aspects, the methods above disclose an entirely self-expanding prosthesis 100 but it is contemplated that any portion or the entire prosthesis 100 could be configured to be balloon- expanded according to conventional techniques in the art.

[0057] Referring to Figure 12, a first example of a delivery system 128 configured for transapical delivery of a prosthesis 100 to an aortic valve is illustrated. In this example, the delivery system 128 can comprises an elongate assembly that further comprises a guidewire 130, a first shaft 132, a second shaft 134, and a pusher assembly 136. In one aspect, the pusher assembly 136, in conjunction with the first and second shafts, 132 and 134 respectively, can be configured to be operable to facilitate a controlled and reversible release of the prosthesis 100 via manipulation by an end user at a point proximal to the entry point of the delivery system 128 into the patient's body. In one aspect, the first shaft 132 defines a central lumen for receiving a guidewire 130 and is configured to receive the suprannular assembly 102, stent assembly 104 and, optionally, a distal anchor assembly 126 in their respective delivery positions on an exterior surface. In a further aspect, the first shaft 132 can be connected to a luer at its proximal end to enable flushing and can have an atraumatic tip co-located with the distal end of the second shaft 134 in an initial delivery configuration. In an additional aspect, the pusher assembly 136 can define a central lumen for receiving the first shaft 132, a luer attached at its proximal end to enable flushing, and can have a plurality of outwardly-biased, hooked filaments configured to bias outward as the second shaft 134 slides proximally to expose the filaments. In this aspect, the hooked filaments can be configured to be operable to releasably secure the proximal apices of the stent assembly 104 during delivery and to enable retrieval and redeployment of at least portions of the prosthesis 100 post-deployment.

[0058] In a further aspect, the delivery system 128 can further comprise a second shaft 134 defining a central lumen for receiving first shaft 132, the pusher assembly 136, and the suprannular assembly 102, stent assembly 104 and, optionally, a distal anchor assembly 126 in their respective delivery positions. In this aspect, the second shaft 134 can be attached to a hemostasis housing that is configured to be selectively and independently bi-axially movable relative to and about the first shaft 132 and guidewire 130. It is contemplated that both the first and second shafts, 132 and 134 respectively^ as well as the pusher assembly 136 can be configured to be selectively and independently bi-axially movable relative to and about the guidewire 130. Additionally, at least a portion of the first shaft 132 can be configured to be movably disposed within the central lumen of the second shaft 134. [0059] In this example, the delivery system 128 is initially guided to the aortic valve and positioned just superior to the native valve. Subsequently as depicted in Figure 13„ the second shaft 134 is moved proximally relative to the first shaft 132, pusher assembly 136 and guidewire 130, thereby releasing the suprannular assembly 102 for positioning and final operational placement at the root of the native valve. In operation, the suprannular assembly 102 expands in an umbrella-like fashion and can be both longitudinally and rotationally positioned such that the commissural posts 116 are positioned in intimate contact with the native valve commissures and the covered wing members 108 are at least partially placed in compressive contact with the native valve leaflets or immediate surrounding tissue. In one aspect, the second shaft 134 is further configured to recapture the at least partially released suprannular assembly 102 and to facilitate either repositioning or retrieval of the suprannular assembly 102 when the second shaft 134 is advanced distally relative to the pusher assembly 136. As depicted in Figure 14, once the suprannular assembly 102 is positioned and deployed in an operative position, the second shaft 134 can be further configured to move proximally to position and deploy the stent assembly 104 within the native valve annulus. As depicted in Figure 15, the second shaft 134 pan be configured to be operable to recapture the at least partially deployed stent assembly 104 and to facilitate either repositioning or retrieval of the stent assembly 104 and, optionally, the deployed suprannular assembly 102, when the second shaft 134 is advanced distally relative to the first shaft 132.

[0060] In a further aspect, the pusher assembly 136 can comprises a set of arms that are operable to bias away from and release the prosthesis 100 when the first shaft 132 is moved proximally. In this aspect depicted in Figure 16, once the first shaft 132 is retracted and the pusher assembly 136 is operatively disengaged from the prosthesis 100, the stent assembly 104 can expand fully to create compressive contact with the native valve annulus, both enlarging the annulus and excluding the native valve leaflets from the blood flow by compressing them between the stent assembly 104 and the covered wing members 108, to substantially encapsulate the native valve leaflets and to minimize undesired embolic discharge into the bloodstreams from the native valve leaflets.

[0061] Figure 17 depicts an additional example of a delivery system 128 configured for transapical delivery of a prosthesis 100 to an aortic valve. In this aspect, the delivery system 128 can comprises the same elements as the prior example with the exception that the second shaft 134 further comprises a distal sheath 140 and a proximal sheath 140. It is contemplated that the distal sheath 140 can be configured to be operable to house and facilitate selective release of the suprannular assembly 102 and, optionally, the distal anchor assembly 126. In various aspects, the distal sheath 140 can be attached to the distal end of the first shaft 132 or, optionally, the atraumatic tip, and can move distally relative to both the second shaft 134 and pusher assembly 136 as the first shaft 132. Thus, the distal sheath 140 can selectively move distally to release the suprannular assembly 102 and selectively move proximally to recapture suprannular assembly 102. In one aspect, the proximal sheath 142 can be configured to house and facilitate selective release of the stent assembly 104 when the stent assembly 104 is moved proximally. In this aspect, the proximal end of the proximal sheath 142 attaches to a hemostasis housing that selectively and independently bi-axially movable relative to and about the guidewire 130.

[0062] In this aspect, the delivery system 128 can initially be guided to the aortic valve and the distal sheath 140 can be positioned proximate to or just superior to the native valve. In this aspect depicted in Figure 18, the distal sheath 140, along with the first shaft 132, can be subsequently advanced distally to expose the suprannular assembly 102, which allows the suprannular assembly 102 to expand in an umbrella-like fashion. In operation, the expanded suprannular assembly 102 can be selectively longitudinally and rotationally positioned such that the commissural posts 116 are positioned in intimate contact with the native valve commissures and the covered wing members 108 are at least partially placed in compressive contact with the native valve leaflets or immediate surrounding tissue. In one aspect, the distal sheath 140 can be further configured to recapture the at least partially released suprannular assembly 102 and facilitate either repositioning or retrieval of the suprannular assembly 102 when the second shaft 134 is advanced distally relative to the pusher assembly 136. As depicted in Figure 19, once the suprannular assembly 102 is positioned and deployed in an operative position, the proximal sheath 142 can be further configured to move proximally to position and deploy the stent assembly 104 within the native valve annulus. In a further aspect, the pusher assembly 136 can comprises a set of arms that are operable to bias away from and release the prosthesis 100 when the first shaft 132 is moved proximally. In this aspect depicted in Figure 21, once the first shaft 132 is retracted and the pusher assembly 136 is operatively disengaged from the prosthesis 100, the stent assembly 104 can expand fully to create compressive contact with the native valve annulus, both enlarging the annulus and excluding the native valve leaflets from the blood flow by compressing them between the stent assembly 104 and the covered wing members 108, to substantially encapsulate the native valve leaflets and to minimize undesired embolic discharge into the bloodstreams from the native valve leaflets.

[0063]

[0064] Optionally, one modification to the above exemplary delivery systems can be provided to accommodate another aspect of the prosthesis 100 where the suprannular assembly 102 and stent assembly 104 are not directly physically connected and are deployed separately. In this aspect, the pusher assembly 136 can be configured to be releaseably connected to the proximal portions of the suprannular assembly 102. In this aspect, the pusher assembly 136 is released once the stent is deployed and has created sufficient compressive contact with the peripheral edge of the wing members to secure the suprannular assembly 102 against further downstream movement. It is an optional feature of this or any other aspect that commissural post extension members 127 or a distal anchor can be employed to further secure the suprannular assembly 102 against migration either during or after deployment of the prosthesis 100. The stent assembly 104 expands fully to create compressive contact with the native valve annulus, both enlarging the annulus and excluding the native valve leaflets from the blood flow by compressing them between the stent assembly 104 and the covered wing members 108, to substantially encapsulate the native valve leaflets and to minimize undesired embolic discharge into the bloodstreams from the native valve leaflets.

[0065] It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope or spirit of the invention. Other aspects of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the invention being indicated by the following claims.

Claims

Claims:

1. An apparatus comprising: a stent assembly selectively movable between a delivery position, in which the stent assembly has a reduced outside diameter, and an operative position, in which the stent assembly has an expanded outside diameter that is positioned in compressive contact with at least a portion of an interior surface of the native valve annulus, wherein the stent assembly has a distal end; a frame assembly selectively movable between a delivery position, in which the frame assembly has a reduced outside diameter, and an operative position, in which the frame assembly has an expanded outside diameter, further comprising a plurality of at least partially arcuate rib members, each rib member having a first end and an opposed, spaced second end, wherein respective rib members of the plurality of rib members are positioned adjacent to each other such that the first end of one rib member is positioned adjacent to the second end of the adjacent rib member, wherein upper portions of the respective adjacent rib members define a plurality of common upwardly extending commissural posts; wherein a lower portion of each of the respective rib members define a downwardly extending wing member; wherein the wing members define a peripheral edge; wherein the frame assembly is operatively coupled to a portion of the stent assembly such that the common commissural posts extend distally of the distal end of the stent assembly and the respective downwardly extending wing members extend downwardly so that the peripheral edge of the wing members at least partially overlies an exterior surface of the stent assembly; a biocompatible covering coupled to the common commissural posts and extending to the peripheral edge of the wing members to thereby define a plurality of covered wing members; wherein an upper portion of the covering that is coupled to a top portion of the commissural posts forms an operative valve having a plurality of leaflets that are configured to operatively open and close the opening defined at a distal end of the formed valve.

2. The apparatus of claim 1, wherein the number of rib members is selected to be equal to the number of native valve leaflets and wherein the rib members are configured such that the common commissural posts are positioned at approximately the same position as the commissural regions of the native valve.

3. The apparatus of claim 2, wherein the plurality of rib members comprise three rib members configured such that the three common commissural posts are positioned approximately 120 degrees apart.

4. The apparatus of claim 3, wherein the native valve is an aortic, mitral, tricuspid or pulmonic valve.

5. The apparatus of claim 1, the upper portion of the biocompatible covering comprises a material selected from the group comprising porcine pericardial tissue, bovine pericardial tissue, equine pericardial tissue, genetically grown tissue, polytetraflouroethylene, polyethylene terephthalate, polyurethane and polyurethane/silicon composites.

6. The apparatus of claim 5, wherein the biocompatible covering further comprises a lower portion extending downwardly from a lower terminal edge of the upper portion of the biocompatible covering and is coupled to the peripheral edge of the respective wing members.

7. The apparatus of claim 6, wherein the lower portion of the biocompatible covering functions to substantially encapsulate the native valve leaflets in order to minimize undesired embolic discharge into the bloodstream therefrom.

8. The apparatus of Claim 6, wherein the upper and lower portions comprise different materials joined together substantially continuously.

9. The apparatus of claim 6, therein the lower portion of the biocompatible material is selected from a group comprising polytetraflouroethylene, polyethylene terephthalate, polyurethane, polyurethane/silicon composites and genetically grown tissue.

10. The apparatus of claim 6, therein the, upper and lower portions of the biocompatible material are formed from the same material.

11. The apparatus of claim 6, wherein the stent assembly, the lower portion of the biocompatible covering and the peripheral edge portions of the wing members of the frame assembly associated with the lower portion of the biocompatible covering comprise a lower region of the apparatus, wherein at least a portion of the ,lower region defines an annulus, and wherein the upper portion of the biocompatible covering is located substantially outside the annulus when the stent assembly and frame assembly are in the delivery and operative positions.

12. The apparatus of claim 1 , further comprising means for compressing at least a portion of the respective covered wing members against at least a portion of the distal surfaces of the native valve leaflets to substantially encapsulate each of the native valve leaflets and to minimize undesired embolic discharge into the bloodstreams from the encapsulated native valve leaflets.

13. The apparatus of claim 12, further comprising means for minimizing paravalvular leakage therebetween the peripheral edge of the wing members and the native valve annulus.

14. The apparatus of claim 13, wherein the biocompatible covering coupled to the common commissural posts and the peripheral edge of the wing members further comprises additional material at the proximal side of the base of each commissural post.

15. The apparatus of claim 12, wherein the frame assembly that is covered with the biocompatible covering forms a suprannular assembly.

16. The apparatus of claim 15, wherein the suprannular assembly is configured to have a maximum deployed diameter against which further expansion is resisted.

17. The apparatus of claim 12, wherein at least a portion of the stent assembly is configured to create compressive contact with the peripheral edge of the wing members.

18. The apparatus of claim 1, wherein the stent assembly is formed from a shape memory material.

19. The apparatus of claim 18, wherein the shape memory material selected from the group comprising nitinol, cobalt chromium and polymers.

20. The apparatus of claim 1, wherein the franie assembly is formed from a shape memory material.

21. The apparatus of claim 20, wherein the shape memory material is nitinol, cobalt chromium and polymers.

22. The apparatus of claim 1, wherein at least one of the frame assembly and the stent assembly is formed from one continuous piece of material.

23. The apparatus of claim 22, wherein both the stent assembly and frame assembly are formed from one continuous piece of material.

24. The apparatus of claim 1, wherein the frame assembly is configured to accommodate the contours of the distal side of the aortic valve and surrounding vasculature.

25. The apparatus of claim 1, wherein at least a portion of the frame and stent assembly further comprise radio opaque markers operative to assist in accurate placement of the apparatus.

26. The apparatus of claim 1, further comprising a distal anchor assembly selectively movable between a delivery position, in which the distal anchor assembly has a reduced outside diameter, and an operative position, in which the distal anchor assembly has an expanded outside diameter that is positioned in compressive contact with at least a portion of the downstream native vessel and that is coupled to at least a portion of the frame assembly.

27. The apparatus of claim 1, further comprising a means for passively creating an interference fit between the distal end of the apparatus and the inner diameter of the native vessel, comprising extension members extending distally from the distal end of the commissural posts configured to be selectively movable between a delivery position, in which the extension members have a reduced outside diameter, and an operative position where the extension members have an expanded outside diameter that is at least equal to the inside diameter of the native vessel.

28. The apparatus of claim 27, wherein the extension members and the frame assembly are formed from one continuous piece of material.

29. The apparatus of claim 27, wherein the extension members are formed separately from and are joined proximate the distal end of the commissural posts.

30. The apparatus of claim 27, where the extension members further comprise a material selected from at least one of the group comprising a shape memory material,

polytetraflouroethylene, and polyethylene terephthalate

31. The apparatus of claim 27, wherein the extension members further comprise a mesh material.

32. The apparatus of claim 27, wherein the extension members are further configured to bias radially outward in an operative configuration to resist any further distal movement of the apparatus when at least one of the stent assembly and frame assembly are in an operative position.

33. A system comprising: the apparatus of claim 15;

a guidewire;

an elongate assembly configured to be disposed within a bodily lumen, the elongate assembly including a first shaft and a second shaft, the first shaft defining central lumen for receiving the guidewire, the second shaft defining a central lumen for receiving the first shaft, the stent assembly in the delivery position and the suprannular assembly in the delivery position, a portion of the first shaft being movably disposed within the central lumen of the second shaft; wherein each of the respective first and second shafts are configured to be selectively and independently bi-axially movable relative to and about the guidewire.

34. The system of claim 33, wherein the second sheath has a diameter of about 10mm or less.

35. The system of claim 34, wherein the second sheath has a diameter of about 5mm or less.

36. The system of claim 35, wherein the second sheath has a diameter of about 3mm or less.

37. The system of claim 33, wherein the second sheath is configured to move proximally to release the suprannular assembly in a position immediately superior to a native valve.

38. The system of claim 37, wherein the second sheath is further configured to move distally to recapture the at least partially released frame assembly.

39. The system of claim 37, wherein the second sheath is configured to move proximally to release the stent assembly in the native valve annulus.

40. The system of claim 39, wherein the second sheath is configured to move distally to recapture the at least partially released stent assembly.

41. The system of claim 33, wherein the first shaft further comprises an atraumatic tip.

42. The system of claim 39, wherein the second shaft further comprises a proximal segment configured to be selectively and independently bi-axially movable relative to and about both the guidewire and first shaft and a distal segment configured to move in concert with at least the first shaft and is bi-axially movable relative to the proximal segment.

43. The system of claim 39, wherein the distal segment of the second shaft is configured to move distally relative to the proximal segment to selectively release the suprannular assembly.

42. The system of claim 41, wherein the distal segment is configured to move proximally to retrieve an at least partially exposed suprannular assembly.

43. The system of claim 39, wherein the proximal segment is configured to move proximally to selectively release the stent assembly.

44. The system of claim 43, wherein the proximal segment is configured to move distally to retrieve an at least partially exposed stent assembly.

45. The system of claim 33, wherein the system further comprises a pusher assembly further defining a central lumen for receiving the first shaft and the second shaft defining a lumen for receiving the pusher assembly.

46. They system of claim 45, wherein the pusher assembly further comprises a plurality of outwardly-biased, hooked filaments configured to bias outward as the second shaft slides proximally to expose the filaments that are operable to releasably secure the proximal apices of the stent assembly during delivery.

47. The system of claim 46, wherein the pusher assembly is further operable upon distal relative movement of the second shaft relative to the pusher to recapture at least one of the suprannular assembly or stent assembly during or after deployment.