Patent Description:
One of the two atrio-ventricular valves in the heart is the mitral valve, which is located on the left side of the heart and which forms or defines a valve annulus and valve leaflets. The mitral valve is located between the left atrium and the left ventricle, and serves to direct oxygenated blood from the lungs through the left side of the heart and into the aorta for distribution to the body. As with other valves of the heart, the mitral valve is a passive structure in that it does not itself expend any energy and does not perform any active contractile function.

The mitral valve includes two moveable leaflets that open and close in response to differential pressures on either side of the valve. Ideally, the leaflets move apart from each other when the valve is in an open position, and meet or "coapt" when the valve is in a closed position. However, problems can develop with valves, which can generally be classified as either stenosis, in which a valve does not open properly, or insufficiency (also called regurgitation), in which a valve does not close properly. Stenosis and insufficiency may occur concomitantly in the same valve. The effects of valvular dysfunction vary, with mitral regurgitation or backflow typically having relatively severe physiological consequences to the patient. Regurgitation, along with other abnormalities of the mitral valve, can increase the workload placed on the heart. The severity of this increased stress on the heart and the patient, and the heart's ability to adapt to it, determine the treatment options that are available for a particular patient. In some cases, medication can be sufficient to treat the patient, which is the preferred option when it is viable; however, in many cases, defective valves have to be repaired or completely replaced in order for the patient to live a normal life.

One situation where repair of a mitral valve is often viable is when the defects present in the valve are associated with dilation of the valve annulus, which not only prevents competence of the valve but also results in distortion of the normal shape of the valve orifice. Remodeling of the annulus is central to these types of reconstructive procedures on the mitral valve. When a mitral valve is repaired, the result is generally a reduction in the size of the posterior segment of the mitral valve annulus. As a part of the mitral valve repair, the involved segment of the annulus is diminished (i.e., constricted) so that the leaflets may coapt correctly on closing, and/or the annulus is stabilized to prevent postoperative dilatation from occurring. Either result is frequently achieved by the implantation of a prosthetic ring or band in the supra annular position. The purpose of the ring or band is to restrict, remodel and/or support the annulus to correct and/or prevent valvular insufficiency. Such repairs of the valve, when technically possible, can produce relatively good long-term results.

However, valve repair is sometimes either impossible or undesirable or has failed, such as in cases where dilation of the valve annulus is not the problem, leaving valve replacement as the preferred option for improving operation of the mitral valve. In cases where the mitral valve is replaced, the two general categories of valves that are available for implantation are mechanical valves and bioprosthetic or tissue valves. Mechanical valves have been used for many years and encompass a wide variety of designs that accommodate the blood flow requirements of the particular location where they will be implanted. Although the materials and design features of these valves are continuously being improved, they do increase the risk of clotting in the blood stream, which can lead to a heart attack or stroke. Thus, mechanical valve recipients must take anti-coagulant drugs for life to prevent the formation of thrombus. On the other hand, the use of tissue valves provide the advantage of not requiring anti-coagulant drugs, although they do not typically last as long as a mechanical valve. Traditionally, either type of valve has been implanted using a surgical procedure that involves opening the patient's chest to access the mitral valve through the left atrium, and sewing the new valve in position. This procedure is very invasive, carries risks of infection and other complications, and requires a lengthy period of recovery for the patient.

To simplify surgical procedures and reduce patient trauma, there has been a recent increased interest in minimally invasive and percutaneous replacement of cardiac valves. Replacement of a heart valve in this way typically does not involve actual physical removal of the diseased or injured heart valve. Rather, a replacement valve is delivered in a compressed condition to the valve site, where it is expanded to its operational state. One example of such a valve replacement system includes inserting a replacement pulmonary valve into a balloon catheter and delivering it percutaneously via the vascular system to the location of a failed pulmonary valve. There, the replacement valve is expanded by a balloon to compress the native valve leaflets against the right ventricular outflow tract, thereby anchoring and scaling the replacement valve. In the context of percutaneous, pulmonary valve replacement, <CIT> and <CIT>, et al. , describe a valved segment of bovine jugular vein, mounted within an expandable stent, for use as a replacement pulmonary valve. As described in the articles: "<NPL> and "<NPL>, the replacement pulmonary valve may be implanted to replace native pulmonary valves or prosthetic pulmonary valves located in valved conduits. Other implantables and implant delivery devices also are disclosed in published <CIT> and <CIT>.

Due to the different physical characteristics of the mitral valve as compared to the pulmonary valve, percutaneous implantation of a valve in the mitral position has its own unique requirements for valve replacement. There is a continued desire to be able to be able to improve mitral valve replacement devices and procedures to accommodate the physical structure of the heart without causing undue stress during operation of the heart, such as providing devices and methods for replacing the mitral valve percutaneously.

The claimed subject-matter is defined in independent claim <NUM>.

Aspects, embodiments and examples of the present disclosure which are not encompassed by the appended claims are not part of the claimed subject-matter and are provided for illustrative purposes. For example, <FIG> show embodiments which do not have all features of the claimed subject-matter.

One embodiment includes a compressible and expandable stent for implantation into a body lumen, such as for replacement of one of the atrioventricular valves. The stent comprises a frame having a central annular region, atrial flares extending from one side of the annular region, and ventricular flares extending from one portion of the opposite side of the annular region. Advantageously, the flares and other features of the stent frames of the present disclosure can be used to create stented valves that can accommodate large orifices and orifices having unusual shapes. With regard to placement within the relatively large mitral orifice, the stented valves can be implanted in such a way that no migration of the valve occurs and so that the left ventricular outflow tract is not obstructed. The valve can be either a pericardial constructor can use an animal valve. The delivery system used for such a stent assembly can consist of a catheter with a sheath at the distal end to maintain the stent assembly in a compressed state for delivery. Further disclosed but not claimed is a method of positioning a valve into a body lumen, such as one of the atrio ventricular valve openings of the heart. The method comprises the steps of compressing a stent frame of a stented valve, wherein the stent frame includes a central annular region, atrial flares, and ventricular flares. The stented valve is then delivered to the annulus of the desired valve area of the patient, which delivery may be performed transapically, for example, In one method, the valve is accessed through the bottom of the valve.

When the valve is in position, the atrial region or portion of the stent is released, and then the delivery system is used to pull the stent valve back against the annulus to engage the atrial portion of the stent with the annulus. The ventricular portion of the stent is then released from the delivery system and the delivery system can be retracted from the patient.

The present invention will be further explained with reference to the appended Figures, wherein like structure is referred to by like numerals throughout the several views, and wherein:.

Referring now to the Figures, wherein the components are labeled with like numerals throughout the several Figures, and initially to <FIG>, one disclosed but not claimed exemplary stent frame is illustrated. Although the stents, such as stent frame <NUM>, are primarily described herein as being used for mitral valve replacement, it is understood that many of the features of these stents can also be used for valves in other areas of the heart. For example, the stents of the invention may be used in the replacement of the tricuspid valve, where the configuration of such a stent may be identical or slightly different than described herein for replacement of the mitral valve due to the different anatomy in that area of the heart. In any case, the stents of the invention desirably restore normal functioning of a cardiac valve, and are intended for percutaneous implantation to take advantage of the benefits of this type of surgery. However, the stents described herein may instead be implanted using surgical techniques that include minimally invasive methods or more traditional open-heart surgical methods.

Exemplary stent frames are shown and described relative to the figures, such as stent frame <NUM>. These stent frames may be fabricated of platinum, stainless steel, Nitinol, or other biocompatible metals or combinations of metals. The stent frames may alternatively be fabricated using wire stock, or the stent frames may be produced by machining or laser cutting the stent from a metal tube, as is commonly employed in the manufacturing of stents. The number of wires, the positioning of such wires, and various other features of the stent can vary considerably from that shown in the figures, while remaining within the scope of the invention.

In any case, the stent frames are preferably compressible to a relatively small diameter for insertion into a patient, but are also at least slightly expandable from this compressed condition to a larger diameter when in a desired position in the patient. It is further preferable that the process of compressing the stents does not permanently deform the stents in such a way that expansion thereof would be difficult or impossible. That is, each stent should be capable of maintaining a desired structural integrity after being compressed and expanded. In one preferred embodiment of the invention, the wires that make up each of the stent frames can be formed from a shape memory material, such as a nickel titanium alloy (e.g., Nitinol). With this material, the stent frame can be self-expandable from a contracted state to an expanded state, such as by the application of heat, energy, or the like, or by the removal of external forces (e.g., compressive forces). The stent frame should be able to be repeatedly compressed and expanded without damaging the structure of the stent frame. In addition, the stent frame may be laser cut from a single piece of material, as described above, or may be assembled from multiple components or wires. For these types of stent structures, one example of a delivery system that can be used includes a catheter with a retractable sheath that covers the stent and its associated valve structure until it is to be deployed, at which point the sheath can be retracted to allow the stent frame to expand. Further details of such a delivery process with stent frames of the present invention are discussed in further detail below.

The stent frames will preferably be used as a part of a stented valve assembly that includes a valve material attached within the inner area of the stent frame to form leaflets. These stented valve assemblies may use a preserved native porcine aortic valve or other vessels or donor species. In order to provide additional valve strength in the relatively highpressure conditions that exist in the mitral valve area of the heart, and/or to provide greater flexibility in designing a valve with a particular size and/or shape, pericardial valves may alternatively be assembled in a tricuspid or bicuspid leaflet configuration.

Referring again to <FIG>, stent frame <NUM> generally includes an annular portion <NUM>, an atrial portion <NUM> extending from one end of the annular portion <NUM>, and a ventricular portion <NUM> extending from the opposite end of the annular portion <NUM>. Annular portion <NUM> includes a wire structure that is shaped in a generally sinusoidal configuration around its perimeter. More particularly, annular portion <NUM> includes two extending posts <NUM> on generally opposite sides of its perimeter, and a sinusoidal pattern having a generally constant height between each of the extending posts <NUM>. This annular portion <NUM> is shown as being formed by a single wire, although it is contemplated that a number of different wires or stent frame components may be assembled to make up this annular portion <NUM>. It is further contemplated that the entire stent frame <NUM> is cut from a single sheet of material such that annular portion <NUM> is part of an integral structure that does not include individual components. The extending posts <NUM> are shown as having a greater height than the portion of the annular portion <NUM> between the posts <NUM>, where the relative size difference between these parts of the annular portion <NUM> can be the same or substantially different than shown. In any case, the height of each of the extending posts <NUM> is designed to provide an attachment area for the leaflet of a valve that will be attached within the stent frame <NUM>. Thus, this example of the stent frame <NUM> that has two extending posts <NUM> is designed to accommodate a bi-leaflet valve; however, it is contemplated that the annular portion <NUM> instead can comprise three extending posts <NUM> to accommodate attachment of a tri-leaflet valve.

It is further contemplated that the stent frame can alternatively or additionally include one or more extending posts that extend in the opposite direction than discussed above relative to the extending posts <NUM>. These extending posts can extend toward the atrial portion of the stent rather than the ventricular portion of the stent.

Atrial portion <NUM> includes a wire structure that is shaped to provide a series of flanges <NUM> that extend radially outward at an angle around the periphery of one end of the annular portion <NUM>. This atrial portion <NUM> is shown as being formed by a single wire, although it is contemplated that multiple wires or stent frame components may be assembled to make up this atrial portion <NUM>, or that the entire stent frame <NUM> is cut from a single sheet of material such no individual wires are used in the construction thereof. As shown, all of the flanges <NUM> are generally the same size and shape and extend at generally the same angle from the annular portion <NUM>, although it is contemplated that the flanges <NUM> are configured differently from each other. The flanges are provided for engagement with one side of the annulus in which the stent frame <NUM> will be implanted, thus, the flanges <NUM> can be provided with a number of different configurations to meet the particular requirements of the locations in which the stent frame may be implanted. For example, the atrial portion <NUM> may have more or less flanges <NUM> than shown, the flanges <NUM> can extend at a greater or smaller angle than shown relative to the generally cylindrical shape of the annular portion <NUM>, the flanges <NUM> can be longer or shorter than shown, and the like.

Ventricular portion <NUM> includes a wire that is arranged to provide a first portion <NUM> that extends in generally the same longitudinal or axial direction as the annular portion <NUM> along a portion of its periphery, and at least one flange <NUM> that extends radially outward at an angle relative to the annular portion <NUM>. This ventricular portion <NUM> is shown as being formed by a single wire, although it is contemplated that multiple wires or stent frame components may be assembled to make up this ventricular portion <NUM>, or that the entire stent frame <NUM> is cut from a single sheet of material such no individual wires are used in the construction thereof. As shown, the first portion <NUM> of the ventricular portion <NUM> is a series of sinusoidal peaks and valleys that are generally the same size and shape as each other, although it is contemplated that they are configured differently from each other. This first portion <NUM> generally follows the outer periphery of the annular portion <NUM> in the axial direction of the stent frame (i.e., there is little to no flare of this portion <NUM> relative to the annular portion <NUM>), where the "peaks" of the wires of portion <NUM> meet the "valleys" of the annular portion <NUM>, such as at an intersection point <NUM>, for example. Such intersection points can occur around the periphery of the stent frame <NUM>. It is further contemplated that the portion <NUM> can be flared at least slightly relative to the annular portion <NUM> in order to engage with the aortic leaflet (i.e., the aortic portion of the ventricular flare) without substantially blocking the left ventricular outflow tract.

The ventricular portion <NUM> further includes at least one flange <NUM> that extends or flares outwardly from the annular portion <NUM> on one side of the stent frame <NUM>. Each flange <NUM> is provided for particular engagement with an annulus in which the stent frame will be implanted, such as the posterior side of a mitral annulus. In this example, the portion <NUM> of the ventricular portion <NUM> does not flare outwardly on the anterior side so that it will not obstruct the left ventricular outflow tract when implanted in the mitral position. Because the flanges <NUM> are provided for engagement with one side of the annulus in which the stent frame <NUM> will be implanted, the flanges <NUM> can be provided with a number of different configurations to meet the particular requirements of the location in which the stent frame may be implanted. In particular, the ventricular portion <NUM> may have more or less flanges <NUM> than shown, the flanges <NUM> can extend at a greater or smaller angle than shown relative to the periphery of the annular portion <NUM>, the flanges <NUM> can be longer or shorter than shown, and the like.

As discussed above, the stent frame <NUM> may comprise a single piece construction, such as a structure that is cut from a single piece of material, or may instead include a series of wires or wire segments that are attached to each other around the periphery of the stent frame <NUM>. In either case, the wire portions of the annular portion <NUM>, the atrial portion <NUM>, and the ventricular portion <NUM> may have the same thickness or different thicknesses from each other. In one example the annular portion <NUM> comprises relatively thick wire portions, while the atrial portion <NUM> and ventricular portion <NUM> comprise relatively thin wire portions. In such an embodiment, the thickness of the wires that make up the atrial portion <NUM> and ventricular portion <NUM> may be the same or different from each other.

<FIG> illustrate a stent assembly <NUM> not showing all features of the claimed subject-matter. Stent assembly <NUM> includes a stent frame <NUM> and a covering material <NUM>. Stent frame <NUM> generally includes a central annular portion <NUM>, an atrial portion <NUM> extending from one end of the annular portion <NUM>, and a ventricular portion <NUM> extending from the opposite end of the annular portion <NUM>. Annular portion <NUM> is similar to the annular portion described above relative to <FIG>, except that the annular portion <NUM> has a wire arrangement that includes two members <NUM> on generally opposite sides of the annular portion <NUM> that are somewhat wider than the extending posts <NUM> of stent frame <NUM>. These members <NUM> have a height that is greater than that of the remainder of the annular portion <NUM>. The wire between each of the members <NUM> around the periphery of the annular portion <NUM> is arranged in a generally sinusoidal pattern. The atrial portion <NUM> includes a wire that is arranged to provide a series of flanges <NUM> that extend radially outward at an angle from one end of the annular portion <NUM>. All of the flanges <NUM> are generally the same size and shape and extend at generally the same angle from the annular portion <NUM>, although it is contemplated that the flanges <NUM> are configured differently from each other. Ventricular portion <NUM> includes a wire that is shaped to provide a first portion <NUM> that extends in generally the same longitudinal or axial direction as the annular portion <NUM> along a portion of its periphery, and at least one flange <NUM> that extends radially outward at an angle relative to the annular portion <NUM>. First portion <NUM> may alternatively be flared at least slightly relative to the annular portion <NUM> in order to engage with the aortic leaflet, without substantially blocking the left ventricular outflow tract. First portion <NUM> is arranged as a series of sinusoidal peaks and valleys that are generally the same size and shape as each other, although it is contemplated that they are different from each other.

The stent frame <NUM> may include a number of wires or wire portions that are attached to each other generally as shown in the illustrated configuration, where one arrangement could include separate wires for each of the annular portion <NUM>, the atrial portion <NUM>, and the ventricular portion <NUM>. Alternatively, the entire stent frame <NUM> may be cut from a single sheet of material such that the stent frame <NUM> is an integral structure that does not include individual components. The relative sizes and number of wire peaks, valleys, and flanges illustrated for each of the portions of the stent frame <NUM> are exemplary, and the construction can instead include different sizes, numbers, and configurations of these components. In addition, this stent frame <NUM> can include any of the variations discussed above relative to stent frame <NUM>, including a variation that includes three extend ing members <NUM> to accommodate the attachment of a tri-leaflet valve within the frame instead of the bi-leaflet attachment arrangement shown.

Stent assembly <NUM> further includes a covering material <NUM> that is attached to at least some of the wires of the stent frame <NUM>, and may be attached to all of the wires or wire portions of stent frame <NUM>, if desired. The covering material can be cut before or after attachment to the stent frame <NUM> to allow for a valve structure (not shown) to be attached to the stent frame <NUM> within the central area of the annular portion <NUM>. The covering material <NUM> can be a knit or woven polyester, such as a polyester or PTFE knit, which can be utilized when it is desired to provide a medium for tissue ingrowth and the ability for the fabric to stretch to conform to a curved surface. Polyester velour fabrics may alternatively be used, such as when it is desired to provide a medium for tissue ingrowth on one side and a smooth surface on the other side. These and other appropriate cardiovascular fabrics are commercially available from Bard Peripheral Vascular, Inc. of Tempe, Arizona, for example. The covering material may be attached to its respective stent frame by sewing, adhesives, or other attachment methods.

<FIG> illustrate a stent frame <NUM> not showing all features of the claimed subject-matter. The stent frame <NUM> generally includes a central annular portion <NUM>, an atrial portion <NUM> extending from one end of the annular portion <NUM>, and a ventricular portion <NUM> extending from the opposite end of the annular portion <NUM>. Annular portion <NUM> is similar to the annular portion described above relative to <FIG> in that it includes a wire portion that is shaped to provide two extending posts <NUM> on generally opposite sides of the annular portion <NUM>, and a generally sinusoidal pattern between each of its extending posts <NUM>. In this embodiment, the annular portion <NUM> further includes V-shaped support members <NUM> that are arranged with the base of each "V" of the V-shaped members <NUM> generally coinciding with the base of an extending post <NUM>. These V-shaped members <NUM> have a similar configuration to the extending members <NUM> of stent frame <NUM> in that the stent frame <NUM> includes a combination of extending posts <NUM> along with V-shaped members <NUM>. These V-shaped members <NUM> can be used to provide additional structural integrity to the stent frame <NUM>.

The atrial portion <NUM> includes a series of flanges <NUM> that extend radially outward at an angle from one end of the annular portion <NUM>. All of the flanges <NUM> are shown as being generally the same size and shape and extend at generally the same angle from the annular portion <NUM>, although it is contemplated that at least some of the flanges <NUM> are configured differently from each other. Ventricular portion <NUM> includes a wire that is arranged to provide a first portion <NUM> that extends in generally the same longitudinal or axial direction as the annular portion <NUM> along a portion of its periphery, and at least one flange <NUM> that extends radially outward at an angle relative to the annular portion <NUM>. First portion <NUM> may be flared at least slightly relative to the annular portion <NUM> in order to engage with the aortic leaflet without substantially blocking the left ventricular outflow tract. First portion <NUM> is arranged as a series of sinusoidal peaks and valleys that are generally the same size and shape as each other, although it is contemplated that they are differently sized and/or shaped from each other.

The stent frame <NUM> may include a number of wires or wire portions that are attached to each other generally as shown in the illustrated configuration, where one arrangement could include separate wires for each of the annular portion <NUM>, the atrial portion <NUM>, and the ventricular portion <NUM>. In one example, the V-shaped members <NUM> are crimped to other wires of the stent frame <NUM>. Alternatively, the entire stent frame <NUM> may be cut from a single sheet of material such that the stent frame <NUM> is an integral structure that does not include individual components. The relative sizes and number of wire peaks, valleys, and flanges illustrated for each of the portions of the stent frame <NUM> are exemplary, and the construction can instead include different sizes, numbers, and configurations of these components. In addition, this stent frame <NUM> can include any of the variations discussed above relative to the stent frames described herein, including a variation that includes three extending posts <NUM> to accommodate the attachment of a tri-leaflet valve within the frame instead of the bi-leaflet attachment arrangement shown.

<FIG> illustrate a stent assembly <NUM> not showing all features of the claimed subject-matter. The stent assembly <NUM> comprises a stent frame <NUM> that is generally similar to the stent frame <NUM> described above relative to <FIG>, and further including a covering material <NUM>. As with the covering material <NUM> described above, covering material <NUM> can similarly include materials that facilitate at least some tissue ingrowth. The covering material <NUM> can be cut between extending posts <NUM> of stent frame <NUM>, such as generally along cut line <NUM>, to allow for attachment of a valve (not shown) that will be positioned within the interior area of the stent frame <NUM>. This stent frame and assembly, along with many other stents of the invention, may be provided with portions that are made of self-expandable materials and other portions that are made of balloon-expandable materials. With particular reference to <FIG>, for example, the atrial and ventricular portions may be made of a self-expanding material, while the central annular portion may be made of a balloon-expandable material to allow for high radial force at the annulus.

<FIG> illustrate a stent frame <NUM> not showing all features of the claimed subject-matter. The stent frame <NUM> generally includes an annular portion <NUM>, an atrial portion <NUM> extending from one end of the annular portion <NUM>, and a ventricular portion <NUM> extending from the opposite end of the annular portion <NUM>. Annular portion <NUM> includes wire or wire portions that cross each other around the periphery of the stent frame <NUM> in a series of X-shaped structures. The stent frame <NUM> includes one or more wires shaped to provide a series of flanges <NUM> that extend radially outward at an angle from one end of the annular portion <NUM>. All of the flanges <NUM> are shown as having generally the same size and shape and as extending at the same angle from the annular portion <NUM>, although it is contemplated that the flanges <NUM> are configured differently from each other. At least some of the flanges <NUM> also include one or more barbs or extensions <NUM>, where this illustrated example includes two barbs <NUM> near the distal tip of each of the flanges <NUM>. Each of the barbs <NUM> preferably extends from its respective flange <NUM> in such a way so that when the stent frame <NUM> is positioned relative to the annulus of a valve in which it will be implanted, the barbs <NUM> will be engageable with the tissue to which they are adjacent. Thus, as is best illustrated in <FIG>, barbs <NUM> extend downwardly or toward the annular portion <NUM> of the stent frame <NUM> so that they can engage with the structure of the heart when implanted. It is understood that the barbs <NUM> can have a different size, shape, orientation, positioning, etc. than shown, and that the each of the flanges <NUM> can include more or less than the two barbs <NUM> shown. Further, it is contemplated that only some of the flanges <NUM> include such barbs <NUM>.

The ventricular portion <NUM> includes a wire that is shaped to provide two extending posts <NUM> on generally opposite sides of the stent frame <NUM>, at least one flange portion <NUM> extending radially outward from annular portion <NUM> on one side of the stent frame <NUM> between extending posts <NUM>, and a sinusoidal wire pattern on the other side of the stent frame <NUM> between extending posts <NUM>. At least some of the flanges <NUM> also include at least one barb <NUM>, where this illustrated example includes two barbs <NUM> near the distal tip of each of the flanges <NUM>. Each of the barbs <NUM> preferably extends from its respective flange <NUM> in such a way that when the stent frame <NUM> is positioned relative to the annulus of a valve in which it will be implanted, the barbs <NUM> will be engageable with the tissue to which they are adjacent. Thus, as is best illustrated in <FIG>, barbs <NUM> extend upwardly or toward the annular portion <NUM> of the stent frame <NUM>. As with the barbs <NUM> described above, barbs <NUM> can have a different size, shape, orientation, positioning, etc. than shown, and each of the flanges <NUM> can include more or less than the two barbs <NUM> shown. Further, it is contemplated that only some of the flanges <NUM> include barbs <NUM>.

<FIG> illustrates an exemplary pattern <NUM> for a stent frame of the type illustrated above relative to <FIG>. This stent frame pattern <NUM> includes a diamond-shaped pattern that can be cut from a single sheet of material. The stent frame pattern <NUM> can be formed into a tubular shape to make a stent frame. As shown, this example includes a number of barbs <NUM> extending from distal ends of the pattern.

<FIG> illustrates a stent assembly <NUM> not showing all features of the claimed subject-matter. Stent assembly <NUM> includes a stent frame <NUM> and a covering material <NUM>. As shown, the covering material <NUM> is stitched to the stent frame <NUM> along many of the wires of this assembly that are visible. This stent frame <NUM> includes two extending posts <NUM> positioned generally across from each other, which are provided as the commissure posts to which the leaflets of a valve assembly will be attached to provide a bi-leaflet valve.

<FIG> schematically illustrates a portion of a heart <NUM>, with an exemplary stent assembly <NUM>. In particular, heart <NUM> includes a left atrium <NUM>, a left ventricle <NUM>, a mitral valve <NUM> and an aortic valve <NUM>. The broken lines of mitral valve <NUM> illustrate its native leaflets as they would generally be configured prior to implantation of stent assembly <NUM>. In particular, mitral valve <NUM> includes a first leaflet <NUM> on the anterior side of the valve, and a second leaflet <NUM> on the posterior side of the valve. When the native mitral valve <NUM> is operating properly, the native leaflets <NUM>, <NUM> will generally function in such a way that blood flows toward the left ventricle <NUM> when the leaflets <NUM>, <NUM> are in an open position, and so that blood is prevented from moving toward the left atrium <NUM> when the leaflets <NUM>, <NUM> are in a closed position. However, stent assembly <NUM> can be positioned in the area of mitral valve <NUM> when it is not functioning properly (to replace the mitral valve) in accordance with the invention, thereby pushing the leaflets <NUM>, <NUM> out of the mitral valve space, such as are shown as displaced leaflets <NUM> and <NUM>, respectively.

As shown, stent assembly <NUM> includes an annular portion <NUM>, an atrial portion <NUM> including flares extending from one side of the annular portion <NUM> and toward the left atrium <NUM>, and a ventricular portion <NUM> including flares extending from the posterior side of the annular portion <NUM> and toward the left ventricle <NUM>. In order to not block the flow of blood through the aortic valve <NUM>, the ventricular portion <NUM> of the stent assembly <NUM> that is closest to the aortic valve <NUM> does not have flares or has flares that have a minimal height. In this way, the stent assembly <NUM> will not push the leaflet <NUM> to a position in which it will interfere with blood flow through the aortic valve <NUM> and/or interfere with the actual movement or functioning of the leaflets of the aortic valve <NUM>. However, annular portion <NUM> preferably has a sufficient length to provide a suitable area of contact with the annulus of the mitral valve to help to maintain it in its desired position.

As stated above, the stent assemblies can also be implanted for replacement of the tricuspid valve. In particular, if the stent assemblies of the invention are positioned within the annulus of a triscuspid valve, the atrial flares would be removed or made in such as way that they do not contact the apex of the triangle of Koch in order to not disturb the conduction system (i.e., the AV node and bundle of His). In addition, the ventricular flares would not contact the septal portion of the ventricle in order to not disturb the conduction system, wherein these flares can thus be similar to those described above relative to stent assemblies for the mitral area. In addition, the ventricular flares in this embodiment can generally resemble the posterior flares in an inferior and anterior direction (e.g., approximately <NUM>/<NUM> of the flares).

Stent frames of the type described above can be assembled into a stented valve assembly in accordance with the methods described herein, although such valves are not shown in the Figures. One exemplary method for assembling a stented valve generally first includes preparation of a porcine aortic valve, then a subsequent mounting or attachment of the prepared porcine valve to the stent frame using a variety of mounting or attachment techniques. Bi-leaflet, tri-leaflet, and other variations of valve assemblies can be attached within the stent frames described herein.

The various flange portions described above relative to the atrial portions and ventricular portions of the stent frames are generally shown as being V-shaped or U-shaped. However, the flange portions may instead be semicircular, rectangular, oblong, or the like, and may be considerably smaller or larger than shown. In yet another variation, a different flange structure that is more continuous around the periphery of the annular portion of the stent frame can be used (i.e., the flange structure does not comprise a series of adjacent flanges but instead comprises more of a continuous flared structure at one or both ends of the stent frame). In any case, the flange portion(s) are preferably configured to be a shape and size that can provide an anchoring function for the stent assembly when it is positioned to replace a valve. For example, if stent assembly were positioned within the mitral valve annulus any flange portions that extend from the stent assembly on the atrial side can provide interference with the walls of the left atrium, thereby inhibiting motion of the stent assembly.

The atrial flares or flange portions can also incorporate features that enable the stent to be sewn in place as part of an atrial incision closure using various means, such as clips, sutures, and the like. In addition, if the atrial flares or flange portions of a stent progress further upward toward the top of the atrium, the result can provide enhanced stabilization of the prosthesis. One example of a configuration of a stent frame <NUM> that provides such a stabilization feature is illustrated in <FIG>. This and other stent frames comprising stabilization features can engage the native anatomy of the atrium for stable position and fixation of a replacement valve. This concept can be applicable to transcatheter or minimally invasive replacement of an insufficient or stenotic mitral or tricuspid valve. Such stent frames generally include a stent inflow aspect member or members that extend beyond the native valve annulus to match the curvature of the atrium. These members can have a variety of shapes and configurations, but generally all function to prevent antegrade and/or retrograde migration of the valve assembly. The degree of protrusion into the atrium can vary, but can advantageously extend past the inflection point of the radius of curvature. The members can also extend all the way to the top of the atrium, if desired. The members can be discrete or joined at the top of the atrium to generally match the shape of the anatomy. Various covering materials can be used to cover or partially cover the stabilization portion of the stent frame, including materials such as fabric, polymer, tissue, or other biocompatible materials. The material can further be chosen to enhance in-growth and/or to reduce abrasion and trauma, if desired.

In the exemplary embodiment of <FIG>, a stent frame <NUM> is shown as positioned relative to the annulus <NUM> of a native valve, and a hoop or series of hoops <NUM> (indicated by the broken line in atrium <NUM>) extends from a top end of the stent frame <NUM> into the atrium <NUM>, which provides additional stabilization of the stent and can help to minimize stent migration. Referring still to <FIG>, a schematic view of a portion of a heart is shown, including the left ventricle <NUM><NUM>, atrium <NUM><NUM>, papillary muscles <NUM>, and the annulus <NUM> of the native valve. A valve comprising a stent frame <NUM> of the invention is shown as positioned so that its annulus <NUM> is at least slightly higher than the annulus <NUM> of the native valve. Two exemplary leaflets <NUM> are shown as extending from the frame <NUM> at the position of its annulus <NUM>. This positioning of the stent frame <NUM> can reduce its protrusion into the left ventricle <NUM>, which can thereby minimize contact and rubbing of the stent frame <NUM> on the wall of the left ventricle <NUM> and papillary muscles <NUM>. The position of the stent frame <NUM> can also reduce the potential for erosion, arrhythmias and ischemia.

<FIG> illustrate another embodiment of a stent frame <NUM> providing the features described above for positioning and fixation relative to a native valve annulus. <FIG> shows this stent frame <NUM> positioned relative to an atrium <NUM> and ventricle <NUM>. Stent frame <NUM> includes an annular portion <NUM>, an atrial portion <NUM>, a ventricular portion <NUM>, and a securing portion <NUM> extending from the atrial portion <NUM>. Securing structure <NUM> generally includes a series of wires arranged in petals or another configuration that extends from the peaks of the wires of the atrial portion <NUM>. The petals are attached at their distal ends to a disc <NUM> or other structure that maintains the wires in a dome-type shape, as shown. The ventricular portion <NUM> can include any of the features described above relative to the ventricular end of the stent frames, wherein this particular embodiment shows a ventricular portion having flares that extend outwardly relative to a central longitudinal axis of the stent frame <NUM>. The annular portion <NUM> further includes two extending posts <NUM> that are at least somewhat taller or longer than the height of the structure of the annular portion between the extending posts.

<FIG> illustrate another embodiment of a stent frame <NUM> that also includes an atrial portion <NUM> comprising a series of flares that are curved at least slightly toward a central longitudinal axis of the stent frame. The frame <NUM> further includes at least two support wires <NUM> that form an additional securing structure of this embodiment. As shown, this exemplary embodiment illustrates two wires <NUM>, each of which extends between two atrial flares on opposite sides of the frame, thereby helping to maintain the flares in this configuration and providing a dome-shaped support structure. However, it is contemplated that the stent frame <NUM> instead includes more or less than two wires. Further, it is contemplated that wires extend from only some of the flares of the atrial portion <NUM>, as shown, or that all of the flares of the atrial portion <NUM> arc connected to another flare with a support wire <NUM>. In yet another embodiment, which is illustrated in <FIG>, a stent frame <NUM> includes an atrial portion <NUM> having multiple flares that are curved somewhat toward a central longitudinal axis of the stent frame <NUM>. However, this exemplary embodiment does not also include any additional connecting wires between the flares.

<FIG> illustrate yet another embodiment of a stent frame <NUM> that includes an atrial portion comprising flares <NUM> and a series of wires <NUM> extending from the flares <NUM> toward a central longitudinal axis of the stent frame. The wires <NUM> are arranged as petals or another configuration that extends from the peaks of the wires of the atrial portion. The wires <NUM> are attached at their distal ends to a structure <NUM> that maintains the wires in a dome-type shape, as shown. The ventricular portion of the stent frame <NUM> can include any of the features described above relative to the ventricular end of the stent frames, wherein this particular embodiment shows a ventricular portion having flares that extend outwardly relative to a central longitudinal axis of the stent frame. The annular portion further includes two extending posts <NUM> that are at least somewhat taller or longer than the height of the structure of the annular portion between the extending posts.

Any of the stent assemblies described herein relative may include a gasket or other member around its exterior to provide for sealing against para valvular leakage and to facilitate pannus in-growth for stabilization of the stent. Such a gasket or other member may alternatively or additionally be positioned on the interior portion of the stent or on the underside of a cuff provided on the stent.

In addition, it is contemplated that the ventricular flares associated with the stented valves of the invention can house biologics to target infarcts (stem cells, genes, proteins, etc.), which are often located posterior-inferiorly in patients with ischemic mitral regurgitation. The areas of a the stented valves of the invention used for anchoring could also be seeded with cells or biologics to promote ingrowth for quick incorporation into the surrounding tissue. This could aid in eliminating paravalvular leakage and in eliminating migration or embolization of the prosthesis. In one example for a mitral valve replacement, the atrial and annular portions can include pro-ingrowth biologies and the ventricular portion can include therapeutic biologics and/or pro-ingrowth biologics.

The stent assemblies of the present invention may be positioned within the desired area of the heart via entry in a number of different ways. In one example, the stent assembly may be inserted transatrially, where entry may be done either percutaneously or in a minimally invasive technique on a beating heart in which access is through the side of the heart, or even through a standard open heart valve replacement procedure using heart-lung bypass and sternotomy where the described device would be used as an alternative to the standard replacement. In another example, the stent assembly may be inserted transapically, where entry again may be done either percutaneously or in a minimally invasive technique on a beating heart in which access is through the side of the heart. In yet another example, the stent assembly may be inserted transeptally, where entry can be done percutaneously.

Claim 1:
A stent frame (<NUM>, <NUM>) for a prosthetic heart valve, comprising:
an annular portion (<NUM>) comprising first and second ends, a central longitudinal axis, and a generally sinusoidal structure of peaks and valleys;
an atrial portion (<NUM>, <NUM>) extending from the first end of the annular portion (<NUM>) and comprising a generally sinusoidal structure of peaks and valleys, wherein each of the valleys of the atrial portion (<NUM>, <NUM>) extends from a peak of the annular portion (<NUM>);
a ventricular portion (<NUM>) extending from the second end of the annular portion (<NUM>);
and a securing structure (<NUM>, <NUM>) extending from the atrial portion (<NUM>, <NUM>), wherein the securing structure (<NUM>) comprises a dome-shaped structure of wires that extend from the atrial portion (<NUM>) toward the central longitudinal axis,