Patent Description:
The present disclosure generally relates to prosthetic valves for implantation in body channels. More particularly, the present disclose relates to sealing solutions for hybrid surgical prosthetic heart valves configured to be surgically implanted in less time than current valves.

Various surgical techniques may be used to repair a diseased or damaged valve. In a valve replacement operation, the damaged leaflets are excised and the annulus sculpted to receive a replacement valve. Due to aortic stenosis and other heart valve diseases, thousands of patients undergo surgery each year wherein the defective native heart valve is replaced by a prosthetic valve, either bioprosthetic or mechanical. The problem with surgical therapy is the significant insult it imposes on these chronically ill patients and consequent high morbidity and mortality rates.

When the valve is replaced, surgical implantation of the prosthetic valve typically requires an open-chest surgery during which the heart is stopped and patient placed on cardiopulmonary bypass (a so-called "heart-lung machine"). In one common surgical procedure, the diseased native valve leaflets are excised and a non-expandable prosthetic surgical valve is sutured to the surrounding tissue at the valve annulus. Because of the trauma associated with the procedure and the attendant duration of extracorporeal blood circulation, some patients do not survive the surgical procedure or die shortly thereafter. It is well known that the risk to the patient increases with the amount of time required on extracorporeal circulation. Due to these risks, a substantial number of patients with defective valves are deemed inoperable because their condition is too frail to withstand the procedure.

Because of the drawbacks associated with conventional open-heart surgery, percutaneous and minimally-invasive surgical approaches are garnering intense attention. In one technique, and expandable prosthetic valve is configured to be implanted in a much less invasive procedure by way of catheterization. Although these remote implantation techniques have shown great promise for treating certain patients, replacing a valve via surgical intervention is still the preferred treatment procedure.

Accordingly, there is a need for a prosthetic valve that can be surgically implanted in a body channel in a more efficient procedure so as to reduce the time required on extracorporeal circulation. One solution especially for aortic valve replacement is provided by the Edwards Intuity valve system available from Edwards Lifesciences of Irvine, CA. Aspects of the Edwards Intuity valve system are disclosed in <CIT> The Edwards Intuity valve is a hybrid of a generally non-expandable valve member and an expandable anchoring stent that helps secure the valve in place in a shorter amount of time. The implant process only requires three sutures which reduces the time-consuming process of tying knots. A delivery system advances the Edwards Intuity valve with the stent at the leading end until it is located within the left ventricle, at which point a balloon inflates to expand the stent against the ventricular wall. The long handle and delivery system design facilitate access through smaller incisions (mini-sternotomy or right anterior thoracotomy) to avoid conventional full sternotomies.

Despite significant progress in improving the outcomes of surgical heart valve replacements, blood leakage around implanted valves remains a primary concern.

<CIT> relates to a quick-connect heart valve prosthesis that can be quickly and easily implanted during a surgical procedure. The heart valve includes a substantially non-expandable, non-compressible prosthetic valve and a plastically-expandable stent frame, thereby enabling attachment to the annulus without sutures. The prosthetic valve may be a commercially available valve with a sewing ring and the stent frame attached thereto. The stent frame may expand from a conical deployment shape to a conical expanded shape, and may have a cloth covering its entirety as well as a plush sealing flange around its periphery to prevent paravalvular leakage.

<CIT> discloses another Edwards prosthetic heart valve. An implantable prosthetic valve is radially collapsible to a collapsed configuration and radially expandable to an expanded configuration. The prosthetic valve comprises an annular frame, a leaflet structure positioned within the frame and a plurality of outer skirts positioned around an outer surface of the frame, each outer skirt comprising an inflow edge secured to the frame and an outflow edge secured at intervals to the frame. The plurality of outer skirts may include a first outer skirt and a second outer skirt, wherein in the expanded configuration the first and second outer skirts include openings unsecured to the frame between the intervals. The inflow edge of the first annular outer skirt may be secured to the frame with sutures including radiopaque material. The first annular outer skirt may include radiopaque dye.

Various embodiments of the present application provide prosthetic valves for replacing a defective native valve in a human heart. Certain embodiments are particularly well adapted for use in a surgical procedure for quickly and easily replacing a heart valve while minimizing time using extracorporeal circulation (e.g., cardiopulmonary bypass pump).

Various embodiments of hybrid prosthetic heart valve for implant at a heart valve annulus are disclosed herein. The heart valves each comprise a valve member having a non-expandable, non-collapsible annular support structure defining a flow orifice and having an inflow end, the valve member having valve leaflets attached to the support structure and mounted to alternately open and close across the flow orifice and a compressible sealing ring encircling the inflow end of the annular support structure. An expandable stent secured to the inflow end of the annular support structure extends therefrom to an inflow edge, the stent comprising a generally tubular stent frame formed by struts, the stent frame being covered both inside and out by a thin fabric.

Each hybrid prosthetic heart valve also includes supplemental structure on the expandable stent for sealing against paravalvular leakage past the valve.

One such sealing solution includes a band of fabric circumscribing the stent outside of the thin fabric forming a series of pockets around the stent open to an inflow direction. The heart valve may further include a plush fabric cuff surrounding the thin fabric around the inflow edge of the expandable stent, wherein the band of fabric is located approximately midway along the expandable stent, spaced from both the plush fabric cuff and the inflow end of the annular support structure. Alternatively, the band of fabric extends between the plush fabric cuff and the compressible sealing ring and is attached at interrupted locations to the compressible sealing ring to form pockets between the interrupted locations. Still further, the band of fabric is located immediately above the plush fabric cuff, or the band of fabric is secured around the plush fabric cuff, or the plush fabric cuff may instead be secured on top of the band of fabric. In a preferred form, the band of fabric comprises a folded-over sheet of fabric with a rear portion separated from a crenellated front portion at a longitudinal fold line, and the pockets are formed in valleys between peaks of the crenellated front portion.

A second sealing structure is a flap of fabric having a circular inner edge secured between the stent and the valve member and an outer edge that extends outward adjacent and to an inflow side of the sealing ring and radially outward beyond the sealing ring. The flap of fabric may have an undulating outer edge which forms a series of outwardly-protruding lobes around its circumference. The outer edge preferably extends outward beyond the sealing ring by between about <NUM>-<NUM>% of the diameter of the valve member. In one embodiment, the annular support structure of the valve member includes three evenly-spaced commissure posts alternating with three arcuate cusps, and there are three outwardly-protruding lobes each centered about one of the commissure posts. The outwardly-protruding lobes each may extend outward beyond the sealing ring by between about <NUM>-<NUM>% of the diameter of the valve member. The inner edge of the flap of fabric may extend downward within the expandable stent and be secured thereto with sutures. The outer edge may also be intermittently secured to the sealing ring with sutures so as to form the pockets between the sutures.

A third sealing solution comprises a strip of fabric circumscribing the stent outside of the thin fabric having a series of longitudinal pleats formed by folding the strip of fabric longitudinally upon itself at regular intervals to form longitudinal folds and securing the folds with suture to form the pleats. A plush fabric cuff may surround the thin fabric around the inflow edge of the expandable stent, wherein the strip of fabric is located immediately above the plush fabric cuff. The strip of fabric may alternatively extend the entire length of the expandable stent. In a preferred embodiment, the strip of fabric comprises a rectangular strip having a series of tabs spaced intermittently along an upper edge, wherein the rectangular strip is folded upon itself in a manner that places the tabs adjacent one another, wherein the tabs are sewn together and the strip sewn to the outside of the thin fabric to form the pleated skirt.

A further embodiment of sealing structure comprises a compressible O-ring circumscribing the stent outside of the thin fabric located at a junction between the sealing ring and the stent.

A further understanding of the nature and advantages of the present disclosure are set forth in the following description and claims, particularly when considered in conjunction with the accompanying drawings in which like parts bear like reference numerals.

Certain embodiments will now be explained and other advantages and features will appear with reference to the accompanying schematic drawings wherein:.

Certain embodiments attempt to overcome drawbacks associated with conventional, open-heart surgery, while also adopting some of the techniques of newer technologies which decrease the duration of the treatment procedure. The prosthetic heart valves of the present disclosure are primarily intended to be delivered and implanted using conventional surgical techniques, including the aforementioned open-heart surgery. There are a number of approaches in such surgeries, all of which result in the formation of a direct access pathway to the particular heart valve annulus. For clarification, a direct access pathway is one that permits direct (e.g., naked eye) visualization of the heart valve annulus. In addition, it will be recognized that embodiments of the prosthetic heart valves described herein may also be configured for delivery using percutaneous approaches, and those minimally-invasive surgical approaches that require remote implantation of the valve using indirect visualization. However, the latter two approaches - percutaneous and minimally-invasive - invariably rely on collapsible/expandable valve constructs. And, while certain aspects described herein could be useful for such valves and techniques, the primary focus and main advantages of the present application is in the realm of non-expandable "surgical" valves introduced in conventional manners.

One primary focus of the present disclosure is a "hybrid" prosthetic heart valve in which a tissue anchor is implanted at the same time as a surgical valve member resulting in certain advantages. The exemplary unitary prosthetic heart valve of the present disclosure is a hybrid valve member, if you will, with both non-expandable and expandable portions. By utilizing an expandable anchoring skirt or stent coupled to a (surgical) non-expandable valve member, the duration of the anchoring operation is greatly reduced as compared with a conventional sewing procedure utilizing an array of sutures. The expandable anchoring stent may simply be radially expanded outward into contact with the implantation site, or may be provided with additional anchoring means, such as barbs. As stated, conventional open-heart approach and cardiopulmonary bypass familiar to cardiac surgeons are used. However, due to the expandable anchoring stent, the time on bypass is greatly reduced by the relative speed of implant in contrast to the previous time-consuming knot-tying process.

For definitional purposes, the terms "stent," "stent frame" or "coupling stent" refer to a structural component that is capable of anchoring to tissue of a heart valve annulus. The coupling stents described herein are most typically tubular stents, or annular stents having varying shapes or diameters. A stent is normally formed of a biocompatible metal frame, such as stainless steel or Nitinol. More preferably, in the context of the present disclosure the stents are made from laser-cut tubing of a plastically-expandable metal. Other coupling stents that could be used with valves of the present disclosure include rigid rings, spirally-wound tubes, and other such tubes that fit tightly within a valve annulus and define an orifice therethrough for the passage of blood.

A distinction between self-expanding and balloon-expanding stents exists in the field. A self-expanding stent may be crimped or otherwise compressed into a small tube and possesses sufficient elasticity to spring outward by itself when a restraint such as an outer sheath is removed. In contrast, a balloon-expanding stent is made of a material that is substantially less elastic, and indeed must be plastically expanded from the inside out when converting from a contracted to an expanded diameter. It should be understood that the term balloon-expanding stents encompasses plastically-expandable stents, whether or not a balloon is used to actually expand it (e.g., a device with mechanical fingers could expand the stent). The material of the stent plastically deforms after application of a deformation force such as an inflating balloon or expanding mechanical fingers. Consequently, the term "balloon-expandable stent" should be understood as referring to the material or type of the stent as opposed to the specific expansion means. Unless expressly limited by a particular claim, the term stent or stent frame may be self- or balloon-expandable.

The term "valve member" refers to that component of a heart valve that possesses the fluid occluding surfaces to prevent blood flow in one direction while permitting it in another. As mentioned above, various constructions of valve members are available, including those with flexible leaflets and those with rigid leaflets, or even a ball and cage arrangement. The leaflets may be bioprosthetic, synthetic, metallic, or other suitable expedients. In a preferred embodiment, the non-expandable valve member is an "off-the-shelf' standard surgical valve of the type that has been successfully implanted using sutures for many years, such as the Carpentier-Edwards PERIMOUNT Magna® Aortic Heart Valve available from Edwards Lifesciences of Irvine, California, though the autonomous nature of the valve member is not absolutely required. In another embodiment, the valve member comprises a PERIMOUNT Magna® Aortic valve subjected to GLX tissue treatment, which allows for dry packaging and sterilization and eliminates the need to rinse the valves before implantation. In this sense, a "off-the-shelf' prosthetic heart valve is suitable for stand-alone sale and use, typically including a non-expandable, non-collapsible support structure having a sewing ring capable of being implanted using sutures through the sewing ring in an open-heart, surgical procedure.

A primary focus of the present disclosure is a prosthetic heart valve having a single stage implantation in which a surgeon secures a hybrid valve having an anchoring stent and valve member to a valve annulus as one unit or piece (e.g., a "unitary" valve). Certain features of the hybrid anchoring stent and valve member are described in <CIT>. The valves described herein are especially beneficial in a single stage implant procedure, but that does not necessarily limit the overall system to just one part. For instance, the heart valves disclosed herein could also use a base stent or ring followed by implant of a hybrid heart valve. Because the hybrid heart valve preferably has a non-expandable and non-collapsible valve member annular support structure, and a plastically-expandable anchoring stent, it effectively resists recoil of a self-expanded base stent.

As a point of further definition, the term "non-expandable" is used herein to refer to a component of the heart valve that is incapable of expanding from a first, delivery diameter to a second, implantation diameter. However, a non-expandable structure might undergo slight expansion or transient flexing from a rise in temperature, or other such incidental cause such as fluid dynamics acting on leaflets or commissures. Likewise, "non-expandable" does not mean that the implanted valve is incapable of further expansion, as some newer surgical heart valves are capable of post-implant expansion in a so-called valve-in-valve procedure. Typically, a dilation force such as with a balloon must be applied to expand such valves post-implant. Stated another way, "non-expandable" means the valve is not suitable for percutaneous or minimally-invasive deliveries, and must thus be implanted surgically. Conversely, "non-expandable" should not be interpreted to mean completely rigid or a dimensionally stable, as some slight expansion of conventional "non-expandable" heart valves, for example, may be observed.

In the description that follows, the term "body channel" is used to define a blood conduit or vessel within the body. Of course, the particular application of the prosthetic heart valve determines the body channel at issue. An aortic valve replacement, for example, would be implanted in, or adjacent to, the aortic annulus. Likewise, a mitral valve replacement will be implanted at the mitral annulus. Certain features of the present disclosure are particularly advantageous for one implantation site or the other, in particular, the aortic annulus. However, unless the combination is structurally impossible, or excluded by claim language, any of the heart valve embodiments described herein could be implanted in any body channel.

Furthermore, though valve introduction downward through an aorta into position at the aortic annulus is illustrated, the reverse is also contemplated in a transapical procedure, for example. The same goes for the other valve annuluses.

<FIG> is a side view of a hybrid prosthetic heart valve <NUM> of the prior art, which includes an upper non-expandable valve member <NUM> coupled to a cloth-covered anchoring stent <NUM>. <FIG> shows the valve member <NUM> in phantom to illustrate the contours of an expandable frame <NUM> of the anchoring stent <NUM>, and <FIG> is a perspective view of the entire heart valve <NUM> with portions at one commissure post <NUM> cutaway to reveal internal structural leaflet supports.

In all of the views herein the heart valves are shown in an upright orientation with the flow axis aligned vertically. For the purpose of nomenclature, blood flows upward through the valves such that a lower end corresponds to an inflow or inlet end and an upper end corresponds to an outflow or outlet end. Of course, during implant and thereafter the heart valves are not necessarily so vertically oriented.

The valve member <NUM> of the hybrid prosthetic heart valve <NUM> has an inner support structure including three upstanding commissure posts <NUM> alternating with three arcuate cusps <NUM> curving in an inflow direction. Three flexible leaflets <NUM> are supported by the commissure posts <NUM> and cusps <NUM> and extend across a generally cylindrical flow orifice defined therewithin. The leaflets <NUM> are attached to an up and down undulating typically metallic wireform <NUM> defining cusps and commissures via a cloth covering. The upstanding posts <NUM> rise up adjacent to and just outside of the commissures of the wireform <NUM>, and outer tabs <NUM> of the leaflets <NUM> extend underneath the wireform, wrap around the posts, and are secured thereto with sutures.

In the illustrated embodiment, the heart valve <NUM> also includes a highly compliant sealing ring <NUM> extending outward therefrom at approximately the interface between the valve member <NUM> and the anchoring stent <NUM>. The sealing ring <NUM> as well as the expandable frame <NUM> are covered with a thin fabric <NUM> that helps prevent leakage around the outside of the valve once implanted. Furthermore, the sealing ring <NUM> is also suture-permeable and may be used to secure the valve in place in the native annulus. Typically, the sealing ring <NUM> has an inner elastomeric (e.g., silicone) sponge or core covered with a polymer fabric, but may also be folded or rolled fabric.

The expandable frame <NUM> is preferably formed by a series of circumferential and axial or angled struts and has an undulating or scalloped upper strut <NUM>. The stent frame <NUM> assembles within a tubular section of thin fabric <NUM> which is then drawn taut, inside and out, and sewn thereto to form the cloth-covered anchoring stent <NUM>. The anchoring stent <NUM> attaches to an inflow (lower) end of the inner support structure of the valve member <NUM>, typically using sutures connected between fabric that covers both elements. More specifically, the anchoring stent <NUM> preferably attaches to the valve member <NUM> during the manufacturing process in a way that prevents reduction of the valve's effective orifice area (EOA). In this regard, sutures may be passed through apertures or eyelets <NUM> arrayed along the upper or first end <NUM> of the expandable frame <NUM> and then through fabric surrounding components within the prosthetic valve member <NUM>. Other connection solutions include prongs or hooks extending inward from the stent, ties, hook-and-loop, snaps, adhesives, etc..

It should be noted that <FIG> shows the stent frame <NUM> in a tubular, uncrimped state. During process of attaching the thin fabric <NUM>, the stent frame <NUM> may remain tubular, and later the frame will be crimped toward an inflow edge opposite the scalloped upper end <NUM> into a conical delivery configuration as seen in <FIG>. Of course, the frame <NUM> may be crimped first and then covered with fabric. Expansion of the stent <NUM> causes the inflow edge to expand while the opposite edge that is secured to the valve member <NUM> remains generally unchanged in circumference, so that the implanted configuration as seen in <FIG> is again conical but flared outward. The general function of the anchoring stent <NUM> is to provide the means to attach the prosthetic valve member <NUM> to the native aortic root. This attachment method is intended as an alternative to the present standard surgical method of suturing aortic valve bio-prostheses to the aortic valve annulus with multiple suture loops passed through the sealing ring <NUM>, and is accomplished in much less time. Further, this attachment method improves ease of use by eliminating most if not all suturing. The expandable frame <NUM> may be a pre-crimped, tapered, <NUM> stainless steel balloon-expandable stent, desirably covered by the thin fabric <NUM>, preferably polyester, to help seal against paravalvular leakage and promote tissue ingrowth once implanted within the annulus. However, the expandable frame <NUM> may alternatively be self-expanding and the sealing solutions described herein are not limited to one type of frame or another unless stated in particular claims.

The completed valve member <NUM> provides the occluding surfaces for the prosthetic heart valve <NUM>, preferably in the form of flexible bioprosthetic leaflets. For example, the valve leaflets may be taken from another human heart (cadaver), a cow (bovine), a pig (porcine valve) or a horse (equine). Alternatively, the valve member may comprise mechanical components rather than biological tissue. Although an autonomous (e.g., capable of stand-alone surgical implant) flexible leaflet valve member <NUM> is described and illustrated, alternative valve members that have rigid leaflets, or are not fully autonomous may be substituted.

For bioprosthetic valves, an exemplary process includes storing the prosthetic heart valve <NUM> in a preservative solution after manufacture and prior to use. A preservative such as glutaraldehyde is provided within a storage jar. This "wet" storage arrangement applies to the illustrated heart valve <NUM> shown, which includes conventional bioprosthetic leaflets. However, as mentioned above, the heart valve could also be used without a preservative solution for bioprosthetic leaflets that can be dry packaged, such as with the RESILIA® tissue from Edwards Lifesciences, and also for mechanical valves.

<FIG> is an elevational view of another hybrid prosthetic heart valve <NUM>' of the prior art showing a lower expandable anchoring stent <NUM>' covered with an outer sealing layer of plush fabric <NUM>. (The heart valve <NUM>' may be constructed the same as the heart valve <NUM> of <FIG>, and thus like elements will be given like numbers with a prime (') designation. ) The layer of plush fabric <NUM> entirely covers the fabric-covered anchoring stent <NUM>', extending to an undulating upper end just below the sealing ring <NUM>'.

The material of the layer of plush fabric <NUM> may vary, but preferably provides a compressible buffer around the anchoring stent <NUM>. The main functions of the fabric layers covering the stent <NUM>' are to help prevent paravalvular leaks and provide means to securely encapsulate any Calcium nodules on the aortic valve leaflets (if left in place) and/or the aortic valve annulus. Covering the entire anchoring stent <NUM>' eliminates exposed metal and decreases the risk of thromboembolic events and abrasion.

In the present application, the term "thin" or "flat" fabric refers to any number of biocompatible fabrics used in surgical implants, such as polytetrafluoroethylene (PTFE) cloth, e.g., TEFLON® PTFE (DuPont), although other biocompatible fabrics may be used. More particularly, the thin fabric is a PTFE flat yarn obtained from Atex Technologies Inc. of Pinebluff, NC. The thickness of the thin fabric is desirably about <NUM>.

The term "plush," "fuzzy" or "fluffy" layer or fabric refers to a much thicker material to provide enhanced prevention of paravalvular leakage. For instance, the plush layer is formed of polyethylene terephthalate (PET) in a single layer or multiple layers, PTFE (TEFLON® PTFE), a silicone ring covered by fabric, or other similar expedients. More preferably, a plush fabric disclosed herein has a base yarn which is flat yarn <NUM>/<NUM>, and a loop yarn extending therefrom made from PET <NUM>/<NUM> textured yarn both obtained from Atex Technologies Inc. of Pinebluff, NC. The thickness of the plush layer is desirably about <NUM> or more, uncompressed, while the thickness of the thin fabric may be <NUM>% or less of that. In alternative embodiments, different materials can be used for assemblies of the thin fabric and the plush layer, such as PTFE/cloth, PTFE/PET, cloth/cloth, or PTFE or cloth for the thin fabric and a swellable hydrophilic polymer such as an acrylic for the plush layer. In another embodiment, opposite sides of a strip of plush fabric are used to create a sealing flange on the expandable anchoring stent <NUM>. The material of the strip includes a relatively smooth side with rows of ribs of the fabric weave, and a plush or relatively fluffy side with outwardly projecting loops and loose threads of the polymer material. The strip is mounted on the anchoring stent <NUM> with the fluffy side out, or is sewn into a tube with the fluffy side outward and then flattened into a strip and attached to the stent.

<FIG> are elevational and perspective views of another hybrid heart valve <NUM>" of the prior art having a lower expandable anchoring stent <NUM>" shown contracted and expanded, respectively, the stent being covered first with a flat fabric layer <NUM>" and then with a band of plush sealing fabric <NUM> over a lower portion.

In a preferred embodiment, the band of plush fabric <NUM> has an axial dimension of between about <NUM>-<NUM>, and is spaced from the upper end of the expandable frame by a distance that varies between about <NUM>-<NUM>. The lower end of the expandable frame may also be scalloped to follow the upper end, in which case the band of plush fabric <NUM> may also undulate to maintain an even distance with the upper end. If a knitted PET fabric is used, the band of plush fabric <NUM> desirably has a radial thickness of at least twice the thickness of the underlying flat fabric layer <NUM>".

The plush fabric <NUM> over the flat fabric layer <NUM>" provides a secondary sealing structure around the frame <NUM> of the stent <NUM>" which enhances leak prevention. The present application provides a number of other secondary sealing structures that may be utilized and are believed superior to the plush fabric <NUM> in <FIG>.

<FIG> is a perspective cutaway view of a native aortic valve AV between a portion of the adjacent left ventricle LV below the ascending aorta AA. The hybrid heart valve <NUM>" mounts on a distal end of a delivery system <NUM> advanced into position within the aortic valve annulus with the anchoring stent <NUM>" located in the left ventricle LV. The delivery system may include an elongated malleable handle shaft <NUM> terminating in a generally tubular adapter <NUM> that couples to a valve holder <NUM> secured to the valve <NUM>" with sutures, for example, between lower ends of three legs <NUM> of the valve holder <NUM> and the sealing ring <NUM>" of the valve. Further details of an exemplary delivery system <NUM> may be seen in <CIT>.

<FIG> shows a balloon <NUM> of a balloon catheter (not shown) of the delivery system inflated to expand the anchoring stent <NUM>". The balloon catheter advances linearly through the handle shaft <NUM>, adapter <NUM>, and valve holder <NUM> into position within the stent <NUM>". The delivery system <NUM> preferably provides binary position displacement of the balloon <NUM>, either retracted substantially within the handle shaft <NUM> or advanced precisely as far as necessary to expand the anchoring stent <NUM>" of the prosthetic heart valve <NUM>". The balloon <NUM> desirably has a frustoconical profile that expands the anchoring stent <NUM>" into a frustoconical expanded state. Not only does this conform better to the sub annular contours but over expands somewhat the annulus that a larger valve maybe utilized then without the expansion.

An implant procedure involves delivering the heart valve <NUM>" and expanding the anchoring stent <NUM>" at the aortic annulus. Because the valve member of the heart valve <NUM>" is non-expandable, the entire procedure is typically done using the conventional open-heart technique. However, because the anchoring stent <NUM>" is implanted by simple expansion, with reduced suturing, the entire operation takes less time. This hybrid approach will also be much more comfortable to surgeons familiar with the open-heart procedures and commercially available heart valves. Moreover, the relatively small change in procedure coupled with the use of proven heart valves should create a much easier regulatory path than strictly expandable, remote procedures. Even if the system must be validated through clinical testing to satisfy the Pre-Market Approval (PMA) process with the FDA (as opposed to a <NUM>(k) submission), at least the surgeon acceptance of the quick-connect heart valve <NUM> will be greatly streamlined with a commercial heart valve that is already proven, such as the Magna® Aortic Heart Valve from Edwards Lifesciences.

The following disclosure presents a variety of sealing solutions for preventing or reducing paravalvular leakage around a hybrid heart valve, and in particular around its expandable anchoring stent <NUM> and especially between the sealing ring <NUM> and the expandable anchoring stent. It should be understood that unless prevented by mutual exclusivity or as stated, the various solutions described herein may be combined in other ways to result in different configurations, and the scope of the disclosure should not be therefore limited to the explicit embodiments shown. For the sake of uniformity, the components of the prior art hybrid heart valve <NUM> aside from the elements for sealing around the anchoring stent <NUM> will be given like numbers as described above. These include: heart valve <NUM>, valve member <NUM>, anchoring stent <NUM>, expandable frame <NUM>, valve commissures <NUM>, valve cusps <NUM>, leaflets <NUM>, wireform <NUM>, inner stent <NUM>, leaflets <NUM>, sealing ring <NUM>, and thin fabric <NUM> around the expandable stent.

<FIG> is an elevational view of a first hybrid heart valve <NUM> having a multi-layered sealing assembly including a row of inflatable pockets <NUM>, while <FIG> are vertical sectional views through the heart valve showing the pockets that fill with blood for better sealing. The expandable frame <NUM> of the anchoring stent <NUM> is first covered inside and out by a layer of thin fabric <NUM>. A relatively narrow band or cuff of plush fabric <NUM> attaches around an inflow end of the stent <NUM> over the top of the thin fabric <NUM>. As seen in <FIG>, the plush fabric cuff <NUM> is formed by a strip of material folded over to double its thickness. The pockets <NUM> are located in a relatively narrow band also attached over the top of the thin fabric <NUM> and just below the sealing ring <NUM>. The pockets <NUM> help reduce paravalvular leakage between the sealing ring <NUM> and the expandable anchoring stent <NUM>.

<FIG> is a laid-out plan view of an elongated strip <NUM> of fabric used to form the pockets <NUM> in the heart valve of <FIG>. The strip <NUM> is desirably formed of a thin fabric, such as the same PTFE material used for the thin fabric <NUM>. The strip <NUM> includes a rectangular lower portion <NUM> separated from a crenellated or undulating upper portion <NUM> at a longitudinal fold line <NUM>. In this regard, "crenellated" means having peaks and valleys formed by a series of concave and convex curves. <FIG> shows the strip of fabric after being folded in half along the fold line <NUM> for attachment around the expandable anchoring stent. More specifically, the lower portion <NUM> is folded behind the upper portion <NUM>. The folded strip <NUM> is then attached around the circumference of the thin fabric <NUM> using sutures <NUM> or the like. The sutures <NUM> are positioned along a lower edge of the strip <NUM> as well as at the peaks of the crenellated upper edge of the upper portion <NUM> such that the valleys are left unattached. A single line of sutures <NUM> across the crenellated upper edge of the upper portion <NUM> and through the folded-over lower edge of the strip <NUM> may also be used for convenience. Although the upper edge of the upper portion <NUM> of the strip <NUM> is shown crenellated, it may also be linear with only intermittent portions secured by sutures so as to leave other portions unattached for forming the pockets <NUM>.

<FIG> extend, respectively, through one of the peaks and one of the valleys of the folded strip <NUM>. <FIG> indicates outward expansion of one of the pockets <NUM> from regurgitant blood flow which may find its way around the heart valve <NUM> after implantation. That is, the heart valve leaflets <NUM> are shown closed in <FIG>, which in use tends to build up pressure on the outflow side of the valve. This pressure can sometimes force blood around the outside of the valve if there is insufficient paravalvular sealing. Often times, the surrounding anatomy of the native valve annulus and adjacent tissue is highly uneven such that a generally cylindrical prosthetic valve (or conical stent) contacts the anatomy around only portions of its circumference. The pockets <NUM>, in addition to the various layers of fabric, provide an additional barrier preventing blood flow around the valve. The pockets <NUM> can fill with blood and thus expand where there is a space between the anchoring stent <NUM> and the surrounding anatomy.

The folded strip <NUM> is desirably secured around the anchoring stent <NUM> approximately at an axial midpoint thereof. That is, the folded strip <NUM> is located in a narrow band above the inflow end of the stent <NUM>, and preferably above the band of plush fabric cuff <NUM>, while also being below the sealing ring <NUM>, which undulates in the illustrated aortic valve. Of course, the location of the folded strip <NUM> may vary, and it may be enlarged, as will be seen below. In one alternative, the folded strip <NUM> with pockets <NUM> is located just below the sealing ring <NUM> and the plush fabric cuff is enlarged as indicated by the dashed outline <NUM> so that it reaches and covers the lower edge of the strip.

<FIG> illustrates a hybrid heart valve where a fabric-covered anchoring stent <NUM> has a lower sealing cuff or flange <NUM> formed by pockets <NUM> and plush fabric <NUM> on the outside. The anchoring stent <NUM> once again is covered inside and out by a thin fabric <NUM>. As seen in the vertical sectional view of <FIG>, the pockets <NUM> may be formed by a folded-over strip <NUM> of fabric, such as described above with respect to the folded strip <NUM> of <FIG>. The strip of plush fabric <NUM> has approximately the same axial height as the folded over strip <NUM>, both of which are approximately <NUM>-<NUM>% of the axial height of the anchoring stent <NUM>. An inner layer of the folded-over strip <NUM> may be secured around to the anchoring stent <NUM>, while a plurality of circumferentially spaced-apart vertically-aligned seams <NUM> segregate the strip into the pockets <NUM>. That is, an outer layer of the folded-over strip <NUM> is only secured to the anchoring stent at the periodic seams <NUM> such that segments of the upper edge remain loose. As with the pockets described above, regurgitant blood flow around the valve tends to fill the space between the inner and outer layers of the folded over strip <NUM>, such as seen in <FIG>. At the same time, the provision of the plush fabric <NUM> surrounding the strip <NUM> provides good sealing in areas where the anchoring stent <NUM> expands outward into intimate contact with the surrounding anatomy.

<FIG> is a variation of the hybrid heart valve of <FIG>, where a fabric-covered anchoring stent <NUM> has a lower sealing cuff or flange <NUM> formed by a strip of plush fabric <NUM> around which pockets <NUM> are formed. <FIG> is a vertical sectional view through a cusp portion of the heart valve showing the plush fabric <NUM> secured to a lower end of the outside thin fabric layer <NUM> around the anchoring stent <NUM>. A folded-over strip <NUM> of fabric is secured to the outside of the plush fabric <NUM>, and is desirably approximately the same axial height (e.g., about <NUM>-<NUM>% of the height of the stent). A series of circumferentially-spaced vertically-oriented seams <NUM> segment an outer layer of the folded-over strip <NUM> such that a majority of its upper edge is only periodically connected around the stent. As before, paravalvular leakage around the outside of the valve in areas where the stent <NUM> is not in close contact with the surrounding anatomy tends to billow out the outer layer of the strip <NUM> to form the pockets <NUM>. The intermediate layer of the plush fabric <NUM> between the pockets <NUM> and the stent <NUM> provides additional thickness to the sealing flange <NUM> such that a better conforms to an uneven surrounding anatomy.

<FIG> illustrates another version of a hybrid heart valve having a lower plush sealing cuff <NUM> combined with pockets <NUM>. Specifically, a lower band of plush fabric <NUM> is secured to the lower end of the anchoring stent <NUM>. A series of large sealing pockets <NUM> covers the remainder of the anchoring stent, up to the sealing ring <NUM>. The pockets <NUM> may be formed by a generally conical sheet <NUM> of material, such as the same material as the thin fabric <NUM> covering the stent. Although not shown, a circular lower edge of the sheet <NUM> is desirably securely attached around the fabric-covered stent <NUM>. Once again, an upper edge <NUM> may be crenellated or circular. An intermediate circumferential seam (not shown) may also be included to secure the sheet <NUM> to the stent <NUM> and reduce the axial height of the pockets <NUM> thus formed to an upper half of the sheet.

The upper edge <NUM> of the fabric sheet <NUM> is secured to the sealing ring <NUM> at equally spaced intervals, such as at each peak of the crenellated upper edge. A series of spaced-apart sutures <NUM> at the peaks leave the intermediate portions (in this case each of the valleys) unconnected or loose to form the pockets <NUM>. The sutures <NUM> may be spaced far apart such as <NUM>° apart, or close together such as <NUM>° apart. Desirably there are at least <NUM> and no more than <NUM> pockets <NUM>.

The circumferential dimension of the sheet <NUM> at the upper edge <NUM> may be significantly larger than the circumference of the anchoring stent <NUM> at that elevation such that the material between the space-apart sutures <NUM> is somewhat bunched or loose. In this regard, the pockets <NUM> tend to be relatively large, as seen in the top elevational view of <FIG>, where the pockets are shown extending radially outward beyond the upper sealing ring <NUM>. This arrangement greatly assists in reducing paravalvular leakage between the sealing ring <NUM> and the expandable anchoring stent <NUM>. In one embodiment, the sealing cuff <NUM> extends axially between about <NUM>-<NUM>% of the height of the anchoring stent <NUM>, while the sheet <NUM> of material that forms the pockets <NUM> extends the remaining height of the stent up to the sealing ring <NUM>. In accordance with the remarks above concerning combining various embodiments, the sealing cuff <NUM> around the lower portion of the stent <NUM> may be formed in the manner as shown in <FIG> so as to have pockets as well.

In <FIG>, a hybrid heart valve <NUM> has a fabric-covered anchoring stent <NUM> that terminates in a lower plush sealing cuff <NUM> as well as a strip or band <NUM> of pleated fabric just above the sealing cuff. <FIG> is a laid flat plan view of a strip <NUM> of material and technique used to form the band <NUM> of pleated fabric. The strip <NUM> is generally rectangular and includes a series of tabs <NUM> spaced intermittently along an upper edge. The strip <NUM> is folded upon itself in a manner that places the tabs <NUM> adjacent one another, as shown. A needle <NUM> indicates the path of a suture or other filament used to sew the tabs <NUM> together to form the pleated skirt. If necessary, a seam (not shown) along the bottom edge may also be provided. Free ends of the strip <NUM> are then attached together to form the circular or conical band <NUM>. The stacked folds of material of the strip <NUM> that form the pleats remain unconnected to each other so that blood can flow in between them, thus providing additional paravalvular leak protection. The band <NUM> of pleated fabric may be positioned directly above the plush sealing cuff <NUM> or anywhere up to the sealing ring <NUM>.

In particular, <FIG> is an elevational view of a hybrid heart valve where the anchoring stent <NUM> has an elongated pleated skirt <NUM> of fabric placed over a flat fabric layer <NUM>. The skirt <NUM> may be attached to the underlying fabric around the stent <NUM> or just an upper edge may be attached so that the pleated skirt <NUM> forms more of a curtain. The pleated skirt <NUM> desirably extends between a lower edge of the sealing ring <NUM> into close proximity with a lower end of the anchoring stent <NUM>. The pleated skirt <NUM> may be formed in essentially the same manner as described above with respect to <FIG>, in that a strip of material is folded upon itself to form the pleats. <FIG> is a vertical sectional view through a cusp portion of the heart valve, and indicates the two-layer structure of the pleated skirt <NUM>. Namely, the section line passes through an inner layer <NUM> of the strip of fabric that forms the skirt <NUM>, while passing directly down through a slit between the separate pleats so as to show a pleat <NUM> folded on top of the inner layer <NUM>. Once again, because the pleated skirt <NUM> extends downward directly below the sealing ring <NUM>, it provides good leak prevention between the sealing ring and anchoring stent <NUM>. The pleating helps keep the radial profile slim while filling spaces between the frame <NUM> and the surrounding anatomy.

<FIG> illustrate a still further hybrid heart valve having a loose fabric flange or flap <NUM> positioned directly under a sealing ring <NUM> around a non-expandable valve member <NUM>. <FIG> shows the flap <NUM> separated and laid-out in plan view in an annular shape. In a preferred embodiment, the flap <NUM> is a thin fabric such as polyethylene terephthalate (PET). The flap <NUM> includes a circular inner edge <NUM> and an undulating outer edge <NUM> which forms a series of outwardly-protruding lobes <NUM> around its circumference. Prosthetic heart valves typically include three leaflets <NUM> which are supported by the aforementioned internal stent structure of the valve member <NUM>. In the embodiment illustrated in <FIG>, the internal support structure includes an undulating wireform <NUM> and an outer band-like stent <NUM> to which leaflet tabs <NUM> connect, all covered by fabric. The structure forms three commissure posts <NUM> which are shown in the top view of <FIG>.

The sectional view of <FIG> indicates that the flap <NUM> extends under the sealing ring <NUM> and between the stent structure of the valve member <NUM> and the anchoring stent <NUM>. The inner edge <NUM> may be secured to an inside wall of the stent <NUM>, while the outer edge <NUM> remains free. The outer edge <NUM> may extend outward beyond the sealing ring <NUM> by about <NUM>-<NUM>% of the diameter of the valve member <NUM>. Alternatively, the outer edge <NUM> may be intermittently secured to the sealing ring <NUM> so as to form the pockets of sort, as discussed above. When assembled, the flap <NUM> forms three lobes <NUM> that are centered at each of the three commissure posts <NUM>, as seen in <FIG>. Because of the anatomy of the aortic valve, the native commissures rise up adjacent to the prosthetic commissures <NUM>. Although the sealing ring <NUM> is undulating, there may be some mismatch depending on the specific patient, and the outwardly-projected lobes <NUM> help seal this area. <FIG> also shows the outwardly-projecting lobes <NUM> from the bottom of the hybrid heart valve. The lower end of the expandable anchoring stent <NUM> may be crimped into a rounded triangular configuration with the fabric <NUM> being secured thereto with stitches <NUM>.

<FIG> is an elevational view of a hybrid heart valve including a plush fabric layer <NUM> secured over a fabric-covered anchoring stent <NUM>. An upper edge <NUM> of the plush fabric layer <NUM> has a scalloped or undulating shape which rises up at the commissures <NUM> of the valve member <NUM> to cover the entire anchoring stent <NUM> at those locations and dips down at the cusps <NUM>. <FIG> is a vertical sectional view through a cusp portion of the heart valve showing a folded over configuration for the plush fabric layer <NUM>. As mentioned above, because the anatomical area around the prosthetic valve commissures <NUM> is uneven, the provision of the plush fabric <NUM> up closely against the sealing ring <NUM> at the commissures helps prevent leaks in this area.

<FIG> is a still further hybrid heart valve where two plush fabric layers of different size are attached over a fabric-covered anchoring stent. Namely, a first or inner layer <NUM> of plush fabric is secured over the entire anchoring stent <NUM> which is already covered with a thin fabric <NUM>. Over the top of this is a second or outer layer <NUM> of plush fabric which is desirably provided in a narrow band located at the inflow or lower end of the anchoring stent. As seen in the vertical sectional view of <FIG>, these layers <NUM>, <NUM> are single layers, e.g., not folded upon each other, but may also be doubled up. The narrow band that forms the outer layer <NUM> may be relocated to just below the sealing ring <NUM> of the valve member <NUM>, but positioning it at the lower end of the stent <NUM> leaves room underneath the sealing ring <NUM> for seating around the native annulus.

<FIG> illustrates another hybrid heart valve where a tapered plush fabric layer <NUM> is attached over a fabric-covered anchoring stent <NUM>. As seen in <FIG>, the fabric layer <NUM> has a radially wider lower end <NUM> than an upper end <NUM>. The tapered fabric layer <NUM> desirably covers the entire exterior of the anchoring stent <NUM>, but may also be provided in a shorter band as desired. The taper of the fabric layer <NUM> may be linear, as shown, or nonlinear so as to have a flared lower end <NUM> (shown in phantom). Varying the thickness of the fabric layer <NUM> in this regard is facilitated by crimping the anchoring stent <NUM> radially inward more at its lower end, such that the additional fabric does not stick out and interfere with delivery of the valve.

<FIG> shows a hybrid valve with a fabric-covered anchoring stent <NUM> having a plurality of patches <NUM> of plush fabric attached around a lower end in an alternating pattern. That is, the patches <NUM> are provided in two horizontal rows; a first row 232a located along the lower end of the stent <NUM> and a second row 232b directly above the first row. Each row 232a, 232b has a series of evenly spaced rectangular patches <NUM>. The patches in the two rows 232a, 232b are vertically offset so as to form a checkered pattern of sorts. Alternating the patches <NUM> in this regard helps limit the overall radial profile of the fabric-covered stent <NUM>. <FIG> is a vertical sectional view through a cusp portion of the heart valve showing that each of the patches <NUM> is formed by a folded over piece of plush fabric secured to the thin fabric <NUM> of the stent <NUM>.

<FIG> is an elevational view of a hybrid heart valve having a lower plush fabric cuff <NUM> surrounding a fabric-covered anchoring stent. In addition, the valve features and an irregular sealing ring <NUM> around a non-expandable valve member. The sealing ring <NUM> has an undulating shape with upwardly curved commissure regions <NUM> alternating with downwardly curved cusp regions <NUM>. A lower edge <NUM> of the sealing ring <NUM> extends considerably further downward toward the plush cuff <NUM> in the cusp regions <NUM> than with a conventional sealing ring. This is also seen in the vertical sectional view of <FIG>. In a preferred embodiment, the vertical dimension of the sealing ring <NUM> increases from a first value at the commissure regions <NUM> to approximately <NUM> or two times as large at the cusp regions <NUM>. Another way to state this is that the lower edge <NUM> dips down in the cusp regions <NUM> into proximity with the lower plush cuff <NUM>. Another way to define this is that the sealing ring <NUM> at the cusp regions <NUM> extends down approximately <NUM>% of the vertical height of the anchoring stent <NUM>.

<FIG> shows another hybrid heart valve where again a lower plush fabric cuff <NUM> is provided over a fabric-covered anchoring stent <NUM>, and an irregular sealing ring <NUM> extends around a non-expandable valve member. In this embodiment, the sealing ring <NUM> comprises commissure bulges <NUM> below the valve commissures <NUM> alternating with conventional thickness cusp regions <NUM>. That is, a lower edge <NUM> of the sealing ring <NUM> dips down considerably farther at the commissure regions <NUM> that at the cusp regions <NUM>. In one embodiment, the lower edge <NUM> extends down about <NUM>% of the vertical height of the anchoring stent <NUM> into proximity with the lower plush cuff <NUM>.

<FIG> are vertical sectional view through a commissure portion of the heart valve adjacent a surrounding target annulus during implant. The enlarged commissure bulges <NUM> are shown in contact with the surrounding anatomy. When the anchoring stent <NUM> is expanded, the bulges <NUM> at the commissure regions help prevent paravalvular leakage between the sealing ring <NUM> and the anchoring stent <NUM> by conforming to irregular anatomical surfaces and filling spaces. Optionally, an implantation suture <NUM> may be utilized at the commissure regions to help compress and conform the commissure bulges <NUM> against the surrounding anatomy. In this configuration, only three implantation sutures <NUM> are used, one at each of the commissures, to help speed up the valve replacement surgery.

<FIG> illustrates a hybrid heart valve <NUM> with a lower plush fabric cuff <NUM> over a fabric-covered anchoring stent <NUM>. A fabric-covered elastomeric O-ring <NUM> extends around the stent <NUM> just below a regular sealing ring <NUM> circumscribing a non-expandable valve member <NUM>. <FIG> is a vertical sectional view through a cusp portion of the heart valve showing the location of the O-ring <NUM> in the corner or junction formed between the sealing ring <NUM> and the anchoring stent <NUM>. The O-ring <NUM> may comprise an inner core <NUM> of a compressible material such as silicone with a fabric cover <NUM>.

<FIG> shows another hybrid heart valve <NUM> with a lower plush fabric cuff <NUM> over a fabric-covered anchoring stent and a fabric O-ring <NUM> around the stent positioned just below the sealing ring. As seen in <FIG>, the O-ring <NUM> again is attached in a corner or junction between the sealing ring <NUM> and the anchoring stent <NUM> and in this embodiment comprises only fabric. The plush fabric cuff <NUM> may be in the form of a cylindrical O-ring, as shown, or simply a narrow band or folded tube of the plush fabric secured directly under the sealing ring <NUM>.

Inclusion of the O-rings <NUM>, <NUM> underneath the sealing ring <NUM> in the valves seen in <FIG> provides additional paravalvular sealing between the sealing ring and the anchoring stent <NUM>. This functions much like the irregular sealing rings <NUM>, <NUM> in <FIG> in that more compressible material is provided between the dimensionally-stable valve member <NUM> and the expandable anchoring stent <NUM>. Additional implantation sutures may be utilized through the O-rings <NUM>, <NUM> which can be pulled taut to help further seal against the surrounding anatomy.

<FIG> is a still further hybrid heart valve <NUM> again with a lower plush fabric cuff <NUM> over a fabric-covered anchoring stent <NUM>. In addition, a fabric-covered elastomeric O-ring <NUM> surrounds and is attached to the cuff <NUM>. <FIG> is a vertical sectional view through a cusp portion of the heart valve which shows an attachment suture <NUM> in a line of such sutures holding the O-ring <NUM> against cuff <NUM>. In the illustrated embodiment, the O-ring <NUM> has an inner core <NUM> of compressible material such as silicone and a fabric covering, though the O-ring may also be entirely made of fabric. When the anchoring stent <NUM> expands outward into contact with the surrounding anatomy, the combination of the plush cuff <NUM> and surrounding O-ring <NUM> provide exemplary paravalvular sealing around the lower end of the stent. Moreover, the O-ring <NUM> on top of the cuff <NUM> helps to better secure the anchoring stent <NUM> against the surrounding tissue.

In <FIG>, a hybrid heart valve features a lower plush fabric cuff <NUM> secured around a foam strip <NUM> that is attached around a lower end of a fabric-covered anchoring stent <NUM>. With reference to <FIG>, the fabric cuff <NUM> and foam strip <NUM> are shown attached coincident with the lower end of the anchoring stent <NUM> and directly on top of one another. The foam strip <NUM> may be made of a memory foam (i.e., viscoelastic foam) which conforms better to uneven or heavily-calcified region surrounding the valve and has somewhat less elasticity so as to rebound less. Memory foam consists mainly of polyurethane as well as additional chemicals increasing its viscosity and density. It may be referred to as "viscoelastic" polyurethane foam, or low-resilience polyurethane foam (LRPu). The foam bubbles or 'cells' are open, effectively creating a matrix through which air can move. The cuff <NUM> and strip <NUM> may be secured with sutures, adhesives, or other such attachment means. Again, the combination of the compressible foam strip <NUM> with the plush fabric cuff <NUM> over the top provides good sealing around the lower end of the stent.

<FIG> is another hybrid heart valve <NUM> with a fabric-covered anchoring stent <NUM> around which is provided a hydrophilic swellable band <NUM>. The band <NUM> preferably has an inner core <NUM> of swellable material and a fabric cover <NUM>. <FIG> is a partial cutaway and sectional view showing the band <NUM> after swelling. In a preferred embodiment, the band <NUM> extends along the entire height of the anchoring stent <NUM>, or at least a majority of the height. The material of the inner core <NUM> is hydrophilic such as a hydrogel designed to swell upon absorption of water after implant. Thus, the anchoring stent <NUM> is first expanded into contact with the surrounding anatomy, after which the inner core <NUM> starts to swell as indicated by the outward arrows and fills in any uneven spaces between the stent and anatomy. The band <NUM> thus remains thin during implantation and only swells over time after implant.

With reference to <FIG>, a hybrid heart valve <NUM> features a fabric-covered anchoring stent <NUM> around the lower end of which is provided a fabric-covered foam band <NUM>. The band <NUM> preferably has an inner core <NUM> of foam material and a surrounding fabric cover <NUM>, as seen in <FIG>. Attachment sutures <NUM> are shown connecting the band <NUM> to the outside of the stent <NUM>, though the band may also be attached using adhesives or the like. The material of the inner core <NUM> may be open-or closed-cell foam, and may be memory foam as described above. Indeed, any of the sealing structures having inner compressible cores disclosed herein may be formed of a variety of materials, in particular memory foam.

Alternatively, the band <NUM> shown in <FIG> represents a coating over a plush fabric cuff on the anchoring stent <NUM>. Providing such a coating <NUM> smooth out the otherwise fuzzy fabric cuff which facilitates advancement through the body and implantation at the annulus. The coating <NUM> be bioresorbable so as to dissolve once in contact with the tissue either by moisture or by heat, or other mechanisms. The coating <NUM> thus makes the seating procedure easier and may be seeded with chemicals that promote cell growth thereafter.

<FIG> is an elevational view of a hybrid heart valve <NUM> where the fabric-covered anchoring stent <NUM> has an external layer <NUM> of bioprosthetic tissue or tissue adhesive material (e.g., fibrin glue) covering its entire external surface. The bioprosthetic tissue may be bovine pericardial sheet which accelerates tissue ingrowth after implant. <FIG> shows the layer <NUM> directly connected on the outside of the stent <NUM>, which can be via sutures through the thin fabric cover <NUM>, adhesives, or the like.

Alternatively, the external layer <NUM> may represent a foam that has been impregnated into the thin fabric <NUM> of the anchoring stent <NUM>. The foam <NUM> may be activated upon illumination with UV light so that it expands and spreads outward toward the annulus, thus enhancing sealing and anchoring. The UV light eventually solidifies the foam <NUM>.

<FIG> illustrates another hybrid heart valve <NUM> where having an extensible fabric skirt <NUM> positioned on the outside of a fabric-covered anchoring stent <NUM>. <FIG> is a vertical sectional view through a cusp portion of the heart valve indicating a direction that the fabric skirt <NUM> extends. Prior to implantation, extensible skirt <NUM> has a length ℓ of approximately the vertical dimension of the anchoring stent <NUM>. During or after implant, the skirt <NUM> may be pulled downward as indicated in <FIG> so as to provide material below the valve for sealing against paravalvular leakage. For example, the skirt <NUM> may initially be provided in a bunched-up state so that it may be stretched longer. The final length L may be up to about double the initial length ℓ.

As mentioned above, the present application may involve combination of various sealing solutions disclosed herein, as long as they are not mutually exclusive. The following discussion pertains to interactive sealing devices which are deployed during implantation of the hybrid heart valve. Any of these interactive solutions maybe utilized with any of the fixed sealing structures disclosed above.

In a first example, <FIG> disclose a hybrid heart valve <NUM> mounted on a distal end of a delivery system <NUM> having an elongated malleable handle shaft, as seen above in <FIG>. The shaft terminates in a generally tubular adapter <NUM> that couples to a valve holder <NUM> secured to the valve <NUM> with sutures, for example, between lower ends of three legs <NUM> of the valve holder <NUM> and the sealing ring <NUM> of the valve.

As mentioned, the heart valve <NUM> may be similar to that of the prior art, or any of the various heart valves disclosed herein. The heart valve <NUM> is shown exploded from a coiled layer <NUM> of fabric in <FIG> which is assembled over the fabric-covered anchoring stent <NUM> in <FIG>. The layer <NUM> is desirably formed of a stretchy fabric which may be pulled taut around the stent <NUM> so that its free ends <NUM> overlap. <FIG> shows the assembled valve with the layer <NUM> held in its stretched configuration by sutures, clips or the like. In a preferred embodiment, a suture attached to the holder <NUM> maintains the layer <NUM> in its stretched configuration and can be severed and removed to release the layer <NUM>. The layer <NUM> is initially stretched tight around the anchoring stent <NUM> to minimize its radial profile for ease of delivery of the valve.

Once the valve is seated, tension on the layer <NUM> may be released. <FIG> shows the assembled valve after tension in the stretched fabric layer <NUM> has been released to create bunches in the layer. The release of tension can be accomplished by cutting the suture(s) that hold the layer <NUM> in tension, or by otherwise removing clips or other such structure. When the tension is released, the layer <NUM> uncoils and tends to form bunches as indicated by the wavy lines which help seal around the anchoring stent <NUM>.

<FIG> show another hybrid heart valve <NUM> having a fabric-covered anchoring stent <NUM> and an inflatable sealing ring <NUM> around a non-expandable valve member <NUM>. The sealing ring <NUM> may have a chamber <NUM> therein and a fill valve <NUM> located on an upper surface thereof so as to be accessible from the outflow side of the valve <NUM> via a fill tube <NUM>. <FIG> are vertical sectional views through a cusp portion of the heart valve showing inflation of the sealing ring <NUM> with a hydrogel <NUM>, for example. While being inflated, the hydrogel <NUM> expands the sealing ring <NUM> against the surrounding anatomy to fill any spaces therebetween. The material of the sealing ring <NUM> is desirably stretchable to enable uneven expansion from inflation into spaces formed by the surrounding uneven anatomy. Eventually, the hydrogel <NUM> cures to prevent fluid flow through the sealing ring <NUM>, and of course the fill tube <NUM> is removed.

Next, <FIG> are vertical sectional views through a hybrid heart valve illustrating a procedure for introducing a curable sealing adhesive or medium <NUM> between a fabric-covered anchoring stent <NUM> and surrounding tissue. The median may be glycerin or a gelatin-based tissue glue/sealant that can be cured by light. In <FIG> the valve has been advanced so that the sealing ring <NUM> is above the native annulus <NUM> while the anchoring stent <NUM> is located below in the adjacent chamber of the heart (the left ventricle in the case of the aortic annulus). One or more fill tubes <NUM>, which may be preinstalled around the valve, extend between the sealing ring <NUM> and the annulus <NUM>, terminating in the region between the constricted (un-deployed) anchoring stent <NUM> and the adjacent chamber. The curable sealing medium <NUM> in liquid form is then injected between the stent and the chamber wall. Again, there may be a single fill tube <NUM>, or an array of them completely surrounding the valve.

<FIG> shows outward radial expansion of the anchoring stent <NUM> against the surrounding chamber. The liquid sealing medium <NUM> is compressed into a relatively consistent layer. Finally, <FIG> shows introduction of an instrument <NUM> having a plurality of curing lights <NUM> mounted thereon through the valve and inside of the anchoring stent <NUM>. Illumination of the lights <NUM> causes relatively quick curing (solidification) of the sealing medium <NUM>. The instrument <NUM> may be introduced through the valve orifice and then rotated around the inside of the anchoring stent for, or there may be multiple such instruments in a circumferential array. The light-cure tissue sealing adhesive or medium <NUM> can be cured by UV light such as by lights with specific wavelength (e.g., <NUM>-<NUM> or <NUM>-<NUM>). The lights <NUM> on the instrument <NUM> can also be integrated into the tip of the delivery system <NUM>.

<FIG> illustrate a procedure for implanting a hybrid heart valve using a self-adhesive precursor band <NUM> pre-installed just below the annulus. The precursor band <NUM> desirably has a size which closely matches the size of the chamber below the native annulus. In the illustrated embodiment, the left ventricle LV is located just below the aortic annulus AA. Consequently, the band <NUM> may be sized so as to closely fit within the left ventricle LV just below the aortic annulus AA, or may be somewhat adjustable to compensate for mismatches in size. The band <NUM> includes a series of self-adhesive outer patches <NUM> that enable it to be secured to the left ventricle LV, as seen in <FIG>.

<FIG> shows a hybrid heart valve <NUM> having the anchoring stent <NUM> thereon being lowered into position at the aortic annulus AA. Again, the heart valve <NUM> may be similar to those of the prior art, or any of the embodiments disclosed herein. The heart valve <NUM> has a fabric-covered anchoring stent <NUM>, and the precursor band <NUM> features a series of patches <NUM> having miniature hooks thereon.

<FIG> shows expansion of the anchoring stent <NUM> contact with the precursor band <NUM>. Because of the miniature hooks on the patches <NUM>, the anchoring stent <NUM> is better secured below the annulus. That is, the hooks on the patches <NUM> connect to the fabric on the stent <NUM> as with any hook and loop (e.g., Velcro® fastener, Velcro BVBA) fastening system.

Claim 1:
A hybrid prosthetic heart valve (<NUM>) for implant at a heart valve annulus, comprising:
a valve member (<NUM>) having a non-expandable, non-collapsible annular support structure defining a flow orifice and having an inflow end, the valve member (<NUM>) having valve leaflets (<NUM>) attached to the support structure and mounted to alternately open and close across the flow orifice and a compressible sealing ring (<NUM>) encircling the inflow end of the annular support structure;
an expandable stent (<NUM>) secured to the inflow end of the annular support structure and extending therefrom to an inflow edge, the stent (<NUM>) comprising a generally tubular stent frame (<NUM>) formed by struts, the stent frame (<NUM>) being covered by a thin fabric layer (<NUM>); and
a narrow band of fabric (<NUM>) circumscribing the stent (<NUM>) outside of the thin fabric layer (<NUM>) forming a series of pockets (<NUM>) around the stent (<NUM>) open to an inflow direction.