GASKET WITH SPRING COLLAR FOR PROSTHETIC HEART VALVES AND METHODS FOR MAKING AND USING THEM

[0001] This application claims benefit of provisional application Ser. No. 60/743,185, filed Jan. 27, 2006, the entire disclosure of which is expressly incorporated herein by reference.

[0002] The present invention relates generally to heart valves that may be implanted within a patient, and, more particularly, to multiple component heart valve assemblies, and to apparatus and methods for making and using them.

[0003] Prosthetic heart valves can replace defective human valves in patients. For example, one piece valves have been suggested that include sewing rings or suture cuffs that are attached to and extend around the outer circumference of a prosthetic valve. In addition, multiple component valves have also been suggested that include a sewing ring that is separate from a valve component. The sewing rings of either type of prosthetic valve can be tedious and time consuming to secure within a target site, i.e., within an annulus of a heart where a natural heart valve has been removed.

[0004] For example, to implant a sewing ring within an annulus of a heart, between twelve and twenty sutures may be secured initially to tissue surrounding the annulus. The sewing ring and/or the entire prosthetic valve may then be advanced or “parachuted” down the sutures into the annulus. Knots may then be tied with the sutures to secure the sewing ring within the annulus, whereupon the sutures may be cut. Consequently, this procedure can be very complicated, requiring management and manipulation of many sutures. The complexity of the procedure also provides a greater opportunity for mistakes and requires a patient to be on cardiopulmonary bypass for a lengthy period of time.

[0005] Because the annulus of the heart may not match the circular cross-section of the sewing ring and/or prosthetic valve, the prosthetic valve may not fit optimally within the annulus. As a result, natural blood hemodynamics through and around the valve may be impaired, resulting in clotting, possible emboli production, and eventual calcification of the valve structure.

[0006] To address this concern, flexible sewing rings have been suggested for use with multiple component valves. The sewing ring may be implanted within the annulus, e.g., using the procedure described above, i.e., parachuted down an arrangement of sutures. The sewing ring may conform at least partially to the anatomy of the annulus. Alternatively, instead of using sutures, it has also been suggested to drive staples through the sewing ring into the surrounding tissue to secure the sewing ring.

[0007] When a mechanical or other prosthetic valve is then attached to the sewing ring, however, the valve and sewing ring may not mate together effectively, e.g., if the shape of the sewing ring has been distorted to conform to the annulus, which may also impair natural blood hemodynamics, create leaks, and/or otherwise impair performance of the prosthetic valve.

[0008] The present invention is directed to heart valves that may be implanted within a patient, and, more particularly, to multiple component heart valve assemblies, and to apparatus and methods for making and using them.

[0009] In accordance with one embodiment, a prosthesis is provided for receiving a prosthetic valve to replace a preexisting natural or prosthetic heart valve within a biological annulus adjacent a sinus cavity. The prosthesis may include an annular member implantable within the biological annulus, a collar extending upwardly from the annular member, and a sewing ring extending radially outwardly from at least one of the annular member and the collar. The collar and/or annular member may be resiliently compressible, expandable, and/or otherwise movable relative to one another. For example, the collar may be biased to a predetermined orientation, e.g., substantially aligned with a longitudinal axis of the annular member, yet may be compressible axially towards the annular member and/or movable transversely relative to the longitudinal axis.

[0010] In accordance with another embodiment, a prosthesis is provided for receiving a prosthetic valve to replace a preexisting natural or prosthetic heart valve within a biological annulus adjacent a sinus cavity. The prosthesis may include an annular member implantable within the biological annulus for contacting tissue surrounding the biological annulus, a collar for engaging with a prosthetic valve, and a spring structure for supporting the collar away from the annular member, e.g., along a longitudinal axis. For example, the spring structure may allow the collar to be compressed towards the annular member along the longitudinal axis and/or transversely relative to the longitudinal axis, yet be resiliently biased to a predetermined position away from the annular member. Optionally, the prosthesis may include a sewing ring, e.g., extending radially outwardly from at least one of the collar and the annular member. The spring structure may also allow the collar to be deflected, folded, and/or compressed transversely relative to the longitudinal axis, e.g., to facilitate accessing the sewing ring and/or annular member during implantation.

[0011] In accordance with still another embodiment, a heart valve assembly is provided for implantation within a biological annulus. The heart valve assembly may include an annular prosthesis that includes an annular member implantable within a biological annulus, a collar extending upwardly from the annular member, and a spring structure for supporting the collar away from the annular member, e.g., along a longitudinal axis of the annular member. The heart valve assembly also includes a prosthetic valve, e.g., a mechanical or bioprosthetic heart valve, which may have a circular or multiple lobular shape for implantation above the biological annulus.

[0012] Optionally, one or more connectors may be provided on at least one of the collar and the prosthetic valve for securing the prosthetic valve to the annular prosthesis. For example, the one or more connectors may include a plurality of tabs or detents, a drawstring, and the like on the collar for engaging a frame of the prosthetic valve. Alternatively, the one or more connectors may include one or more latches, detents, interlocking elements, e.g., on the prosthetic valve and/or the annular prosthesis.

[0013] In one embodiment, the collar may include a plurality of tabs that capture a portion of a frame of the prosthetic valve when the prosthetic valve is directed into engagement with the collar. Optionally, the tabs may be movable, e.g., using a tool, to release the prosthetic valve from the collar.

[0014] In exemplary embodiments, the collar, annular member, spring structure, and/or sewing ring may be formed from resiliently flexible material, e.g., metal, such as Nitinol, Elgiloy, or stainless steel, an elastomer, such as silicone, or other plastic material, and may be covered at least partially with a fabric covering. The collar, annular member, and/or spring structure may be formed as a unitary piece or may be separate components that are attached to one another, e.g., before or after being covered with fabric.

[0015] In accordance with yet another embodiment, a method is provided for implanting a prosthetic heart valve assembly within a biological annulus, e.g., adjacent a sinus cavity. An annular member may be introduced into the biological annulus, e.g., to direct tissue surrounding the biological annulus outwardly and/or to at least partially dilate the biological annulus. A flexible sewing ring may extend around the annular member that may receive one or more connectors, e.g., sutures, clips, and the like, to secure the annular member relative to the annulus.

[0016] In one embodiment, a collar or stand-off extends upwardly from the annular member for receiving the prosthetic valve. The collar may be coupled to the annular member by a spring structure, which may bias the collar to a predetermined position relative to the annular member, but allow the collar to be moved relative to the annular member. For example, the collar may be folded or otherwise moved transversely to facilitate access to the sewing ring, e.g., for directing one or more connectors through the sewing ring. In addition, the collar may be compressible towards the annular member, but resiliently biased to direct the collar upwardly, e.g., within the sinus cavity above the biological annulus.

[0017] A prosthetic valve, e.g., a mechanical or bioprosthetic valve, may be advanced into the sinus cavity, and secured relative to the annular member. For example, the prosthetic valve may be secured to the collar using one or more connectors, e.g., a plurality of tabs or detents on the collar, a drawstring in the collar, one or more sutures, clips, detents, and/or other cooperating connectors, e.g., on the collar and/or frame of the valve prosthesis.

[0018] The collar may support the prosthetic valve above the tissue biological, e.g., within the sinus cavity, e.g., the sinus of Valsalva above an aortic valve site. In addition or alternatively, the collar may allow the prosthetic valve to have a larger size than the annular member, thereby enhancing the fluid flow or other performance characteristics of the implanted heart valve assembly. Optionally, the collar may include a funnel or other tapered shape that may provide a transition from a relatively larger prosthetic valve to the annular member within the biological annulus. In addition, the collar may support the prosthetic valve away from a wall of the sinus or other supra-annular space, while still allowing blood to flow easily into the coronary arteries around the prosthetic valve.

[0019] In another option, the prosthetic valve may be removable from the collar, e.g., to allow the prosthetic valve to be replaced. In addition or alternatively, the collar and prosthetic valve may have a substantially circular shape, which may allow the prosthetic valve to be secured to the collar, yet be rotatable relative to the collar.

[0020] Other aspects and features of the present invention will become apparent from consideration of the following description taken in conjunction with the accompanying drawings.

[0021] The drawings illustrate exemplary embodiments of the invention, in which:

[0022] FIG. 1 is a partial cross-sectional side view of an exemplary embodiment of a gasket member with a fabric covering.

[0023] FIG. 2 is a side view of a collar including a spring structure and an annular ring that may be provided in the gasket member of FIG. 1.

[0024] FIG. 3A is a cross-sectional side view of an unfinished blank that may be formed into the collar and spring structure of FIG. 2.

[0025] FIG. 3B is a cross-sectional side view of a collar and spring structure formed from the blank of FIG. 3A.

[0026] FIG. 4 is a perspective view of a two piece heart valve assembly including a gasket member of FIG. 1 and a mechanical valve.

[0027] FIG. 5 is a cross-sectional view of an aortic valve site, having the heart valve assembly of FIG. 4 implanted therein.

[0028] Turning to the drawings, FIGS. 1-5 show an exemplary embodiment of a heart valve assembly 10 that generally includes a gasket member 12 and a valve member 14. Generally, the gasket member 12 includes an annular ring 18, a sewing ring 20 extending radially from the annular ring 18, and a collar 22 extending upwardly from the annular ring 18. The valve member 14 may be a prosthetic valve, e.g., a mechanical or bioprosthetic valve, that may be secured to the collar 22 and/or other portion of the gasket member 12, e.g., after implanting the gasket member 12 within a tissue annulus, as described further elsewhere herein.

[0029] Turning to FIGS. 4 and 5, the valve member 14 may be a mechanical valve including an annular frame 32 supporting a pair of valve members 38 (shown in FIG. 5) that open and close within the frame 32. Optionally, the valve member 14 may include a pair of ears 34 extending downwardly from the frame 32, e.g., for pivotally supporting the valve members 38. In an exemplary embodiment, the valve member 14 may be a mechanical valve, such as the “Regent” Bileaflet Valve manufactured by St. Jude Medical. In alternative embodiments, the valve member 14 may be another mechanical or bioprosthetic valve, such as those disclosed in U.S. Pat. No. 6,371,983 or U.S. Publication Nos. 2005/0043760, 2006/0235508, or 2006/0276888, the entire disclosures of which are expressly incorporated by reference herein.

[0030] Returning to FIGS. 1 and 2, an exemplary embodiment of the gasket member 12 is shown that includes an annular ring 18, a sewing ring 20, a collar 22, and a spring structure 40 supporting the collar 22 relative to the annular ring 18. Fabric 24 may cover all or at least a portion of the gasket member 12, e.g., the annular ring 18, the sewing ring 20, the collar 22, and/or the spring structure 40, for example, to allow tissue ingrowth and/or provide desired flexibility, similar to embodiments described in US Publication Nos. 2004/0122516, 2005/0165479, 2006/0195184, and 2007/0016285, the entire disclosures of which are expressly incorporated by reference herein.

[0031] In one embodiment, the annular ring 18 may have a generally circular shape, e.g., defining a central longitudinal axis 19. Alternatively, the annular ring 18 may have a multi-lobular shape about its circumference, e.g., including three lobes separated by scallops or cusps (not shown). In addition or alternatively, the annular ring 18 may generally define a plane substantially perpendicular to the axis 19 or may have a sinusoidal or other shape that extends above and below a plane.

[0032] Optionally, the annular ring 18 may be expandable and/or contractible such that the diameter may be adjusted. In one embodiment, the annular ring 18 may be biased to expand to a predetermined diameter. If desired, the annular ring 18 may be contracted radially to a smaller diameter, e.g., folded or compressed to facilitate delivery into a biological annulus, yet may be resiliently expandable to the predetermined diameter, e.g., to dilate tissue surrounding the biological annulus and/or to facilitate securing the gasket member 12 within the biological annulus.

[0033] The annular ring 18 may be formed from an elastic or superelastic material, e.g., metal such as Nitinol, Elgiloy, stainless steel, and the like, a polymer or other plastic, and/or a composite material. In an exemplary method, the annular ring 18 may be cut from a flat sheet of base material having a desired thickness for the annular ring 18, e.g., by laser cutting, mechanical cutting, and the like. For example, the annular ring 18 may be initially formed as a long band of material (not shown), having a width corresponding to the desired height “h” of the annular ring 18 and a length corresponding to a circumference (π d) of the desired diameter “d” of the annular ring 18, as shown in FIG. 2. The band may be wrapped around a mandrel or otherwise restrained in a generally cylindrical shape with the ends adjacent to one another, and the band may be heat treated or otherwise processed to program the generally cylindrical shape to create the annular ring 18. The generally cylindrical shape may include the ends overlapping one another, spaced apart from one another to provide an open “C” shape, or attached to one another.

[0034] Fabric may be wrapped at least partially around the annular ring 18, while accommodating expansion and contraction of the annular ring 18, if the annular ring 18 is expandable. For example, at least near the ends, the fabric may not be secured to the annular ring 18, while sutures and the like (not shown) may secure the fabric to other portions of the annular ring 18. Alternatively, the entire annular ring 18 may be free to slide within a fabric sleeve (not shown) wrapped around the annular ring 18. Additional information on the construction of the annular ring 18 may be found in the references incorporated by reference elsewhere herein.

[0035] The collar 22 may be spaced apart and/or extend upwardly from the annular ring 18. For example, as best seen in FIGS. 2 and 4, the collar 22 may be coupled to the annular ring 18 by the spring structure 40. Generally, the spring structure 40 may allow the collar 22 to be resiliently compressed or otherwise directed towards the annular ring 18, e.g., substantially along the axis 19. In addition or alternatively, the spring structure 40 may allow the collar 22 to be folded, compressed, or otherwise directed inwardly and/or transversely relative to the axis 19, as described further elsewhere herein.

[0036] The collar 22 may be a generally circular annular band 22 for receiving or otherwise engaging the valve member 14, e.g., as described further below. In one embodiment, the collar 22 may include a lower rim 22a defining a lip 17 and a sidewall 22b extending upwardly from the rim 22a, thereby defining a recess 23 for receiving the valve member 14 therein. In addition, the collar 22 may include one or more connectors, e.g., a plurality of detents 16, for securing the valve member 14 within the recess 23 and/or otherwise to the collar 22. As shown, the detents 16 include tabs extending downwardly and inwardly from the sidewall 22b, e.g., defining an angle relative to the axis 19. The tabs 16 may be biased inwardly but may be resiliently deflectable outwardly, e.g., during introduction of the valve member 14. Lower, free ends 16a of the tabs 16 may be spaced above the lip 17, e.g., for capturing a portion of the valve member 14 between the rim 22a and the tabs 16, as described further below.

[0037] In addition or alternatively, the collar 22 and/or other portion of the gasket member 12 may include one or more connectors in addition to or instead of the detents 16. For example, the collar 22 may include a plurality of fasteners, clips, latches, and the like (not shown) inset within or otherwise attached to the collar 22, e.g., similar to those disclosed in US Publication Nos. 2006/0195184 and 2006/0235508, incorporated by reference above. Alternatively, the gasket member 12 may include a plurality of guide rails or other elongate members (not shown) extending from the collar 22 and/or sewing cuff 20 for guiding the valve member 14 towards the gasket member 12 and/or securing the valve member 14 to the gasket member 12, similar to the elongate members disclosed in Publication No. 2005/0165479, incorporated by reference above, or co-pending application Ser. No. 60/746,038, filed Apr. 29, 2006, the entire disclosure of which is expressly incorporated by reference herein.

[0038] Returning to FIGS. 2-3B, the spring structure 40 may include an annular base 42 and a helically shaped spring member 44 extending upwardly from the base 42, e.g., spiraling around the axis 19. The spring member 44 may be coupled to the collar 22 and the base 42 may be coupled to the annular ring 18. Alternatively, the spring member 44 may be coupled directly to the annular ring 18 and the base 42 may be eliminated (not shown). The spring member 44 may be sufficiently rigid to bias the collar 22 to a predetermined position relative to the annular ring 18. For example, the spring member 44 may bias the collar to align axially above the annular ring 18 along the longitudinal axis 19. In addition or alternatively, the spring member 44 may bias the collar 22 to be spaced a predetermined distance from the annular ring 18, e.g., at a height “x” above the annular ring 18.

[0039] As shown, in one embodiment, the base 42 and spring member 44 of the spring structure 40 and the collar 22 may be formed as a unitary piece. For example, the collar 33 and/or spring structure 40 may be formed by machining, molding, casting, stamping, etching, and the like. Alternatively, the base 42, spring member 44, and/or collar 22 may be formed as separate pieces that are attached to one another, e.g., by bonding, sonic welding, cooperating connectors, interference fit, and the like (not shown). Similar to the annular ring 18, the spring structure 40 and/or collar 22 may be formed from metal, such as Nitinol, Elgiloy, stainless steel, and the like, a polymer or other plastic, and/or a composite material. For example, in an alternative embodiment, the spring member 44 may be a metal spring, the base 42 may be formed from silicone or other elastomer (e.g., also providing a core for the sewing ring 20 as well as a base for the spring member 44), and the collar 22 may be formed from Nitinol or other metal attached to the spring member 44.

[0040] Turning to FIGS. 3A and 3B, in an exemplary embodiment, the collar 22 and spring structure 40 may be formed as a unitary piece from a blank using a laser machining process. Turning to FIG. 3A, a blank may be provided for an unfinished collar 22 that generally includes a lower sidewall section A, an upper sidewall section B, and a base section D, all disposed substantially symmetrically around the longitudinal axis 19. The blank may be formed by machining, molding, casting, and the like from desired materials, e.g., Nitinol, stainless steel, Elgiloy, plastic, and the like. Initially, the blank may have generally cylindrical continuous sidewalls having a greater thickness at section A than at section B, thereby defining lip 17 between sections A and B. The base section D may extend inwardly from section B and may include an opening C therethrough aligned with the longitudinal axis 19, e.g., having a diameter corresponding to the size of the annular ring 18, as seen in FIG. 2. Thus, sections A and B may have a relatively large diameter compared to the opening C.

[0041] Optionally, section D may have a tapered or other shape that may conform at least partially to a shape of a biological annulus into which the resulting annular prosthesis 12 is implanted. In addition or alternatively, section D may include a plurality of openings 28 extending therethrough, e.g., for accommodating sutures, staples or other connectors therethrough. The openings C, 28 may be cut, bored, drilled, or otherwise formed through the base 42 or may be created when the base 42 is molded, cast, and the like.

[0042] Turning to FIG. 3B, a plurality of tabs 16 may be formed through section A. For example, a plurality of elongate openings 21 may be laser cut (or otherwise created) through section A that extend around the circumference of section A. The remaining material around the openings 21 provides the sidewall 22b of the collar 22 and define a plurality of tabs 16. Thus, the tabs 16 may be fixed at upper ends 16b to the sidewall 22b and may include free lower ends 16a. As shown in FIG. 4, at least some of the tabs 16 may be bent inwardly from the sidewall 22b, e.g., by heat-setting the bent shape, bending the tabs 16 beyond their elastic limit, and the like.

[0043] With continued reference to FIGS. 3A and 3B, portions of Section B may be removed, leaving the rim 22b of the collar 22 and the spring member 44. As shown, the spring member 44 may have a height similar to the thickness of Section B, e.g., such that the spring member 44 has a substantially square cross-section. It will be appreciated that other cross-sections may be provided having desired mechanical properties, e.g., a desired spring constant.

[0044] Although described in an exemplary order, it will be appreciated that the sequence of the steps described above for forming the collar 22 and spring structure 40 are merely exemplary. The procedure described may be performed in any order, i.e., such that the collar 22, spring member 44, and/or base 42 may be created sequentially or simultaneously with one another.

[0045] Optionally, as shown in FIGS. 3A-4, a lower recess 29 may be formed or otherwise provided in the base 42 of the spring structure 40, e.g., around opening C. This recess 29 may be sized to receive an upper edge of the annular ring 18 therein.

[0046] With additional reference to FIGS. 1 and 4, the sewing ring 20 may be attached to or otherwise extend around the annular ring 18 and/or spring structure 40. For example, the sewing ring 20 may include one or a plurality of layers of fabric or other material extending radially outwardly from the base 42 and/or the annular ring 18. Alternatively, the sewing ring 20 may include flexible core material 25, e.g., silicone or other elastomeric materials, foam, fabric, felt, polymers, and the like, that may be attached to or otherwise extend around the base 42 and/or annular ring 18, as described in the references incorporated by reference elsewhere herein. Such a core 25 may be molded, fused, bonded, and the like to the base 42 and/or annular ring 18 or may simply be disposed around the base 42 and/or annular ring 18 and held in place by an overlying layer of fabric.

[0047] Generally, to make the annular prosthesis shown in FIG. 1, the annular ring 18 may be formed as described above. Optionally, a lower baleen or skirt 26 may be formed that extends downwardly and/or outwardly from the annular ring 18. The skirt 26 may be formed and/or attached to the annular ring 18 as described in the references incorporated by reference elsewhere herein.

[0048] The collar 22 and spring structure 40 may be formed as described above, before, after, or in conjunction with the annular ring 18 and/or skirt 26. Once formed, the annular ring 18 may be disposed with the upper edge within the recess 29 within the base 42 of the spring structure 40. Optionally, the annular ring 18 may be attached to the base 42, e.g., by bonding, welding, an interference fit, and the like. Otherwise, the upper edge of the annular ring 18 may simply be placed within the recess 29, and fabric may be wrapped around the annular ring 18 and/or base 42 to hold the annular ring 18 adjacent the base 42. Optionally, one or more sutures (not shown) may be directed through openings (also not shown) in the annular ring 18 and base 42 to secure the annular ring 18 adjacent the base 42.

[0049] In an alternative embodiment, the base 42 of the spring structure 40 may be eliminated. In this alternative, the lower end of the spring member 44 may be attached directly to the annular ring 18. For example, the lower end of the spring structure 40 may be bonded, fused, or otherwise attached to an upper region of the annular ring 18.

[0050] If the sewing ring 20 includes a core 25, the core 25 may be attached around the base 42 and/or the annular ring 18. The core material may be bonded, molded, or otherwise attached to the base 42 and/or annular ring 18. Fabric may be wrapped or otherwise secured around the core 25, the annular ring 18, the base 42, the spring member 44, and the collar 22, e.g., using known sewing or other methods. The resulting prosthesis 12 shown in FIG. 1 may be entirely covered with fabric (omitted in part only to show the internal components of the prosthesis 12).

[0051] As fabric is being secured around the collar 22 and/or spring member 44, the collar 22 may be directed and maintained partially towards the annular ring 18. After securing the fabric, the collar 22 may be released, thereby applying tension on the fabric as the spring member 44 attempts to bias the collar 22 away from the annular member 18. This tension may pull the fabric slightly, e.g., to reduce the risk of the fabric puckering. The fabric may cover the tabs 16 within the collar 22 or openings may be provided in the fabric to allow the tabs to extend therethrough. If the fabric covers the tabs 16, the fabric should not be tensioned to cause the tabs 16 to deflected outwardly from their relaxed position.

[0052] Thus, turning to FIG. 4, the resulting annular prosthesis 12 may have a relaxed condition, i.e., free from external forces, in which the collar 22 is spaced apart from the annular ring 18 and/or base 42. The collar 22 may have sufficient height “x” relative to the annular ring 18 to accommodate receiving the frame 32 of the valve member 14 without the ears 34 extending down into the annular ring 18. The collar 22 may include one or more grooves (not shown) formed within the collar 22, which may accommodate the ears 34 of the valve member 14. The collar 22 may have sufficient structural integrity to support the valve member 14, yet be sufficiently flexible to be deformable to facilitate introduction into a patient's body and/or to move the collar 22 away to accommodate delivering one or more connectors (not shown) into the sewing ring 20.

[0053] Turning to FIG. 5, during use, the gasket member 12 may be implanted within a patient's body, e.g., within or adjacent to a biological annulus 90. The biological annulus 90 may be the site for replacement of an existing natural or previously implanted heart valve, such as a tricuspid, mitral, aortic, or pulmonary valve within a patient's heart (not shown). With the annular ring 18 contracted into a relatively small diameter (if the annular ring 18 is radially compressible), the gasket member 12 may be advanced into the annulus using a delivery tool (not shown). Exemplary tools, apparatus, and methods for compressing and/or delivering the gasket member 12 are disclosed in co-pending application Ser. No. 60/746,038, filed Apr. 29, 2006, incorporated by reference above.

[0054] The gasket member 12 may be advanced until the annular ring 18 extends at least partially into the biological annulus 90. In one embodiment, the annular ring 18 extends entirely through the biological annulus 90, with the lower edge of the annular ring 18 remaining free within the sub-annular space below 92 the biological annulus 90.

[0055] Optionally, as shown, the gasket member 12 may include a flexible skirt 26 that extends through the annulus. The skirt 26 may be biased to extend outwardly as shown to provide a smooth transition and/or enhance a seal between the heart vale assembly 10 and the biological annulus.

[0056] The sewing ring 20 may contact the tissue within the supra-annular space 94 above the biological annulus 90, although the sewing ring 20 may not provide any structural support of the annular ring 18. For example, the sewing ring 20 may be substantially flexible, e.g., conforming substantially to the shape of the supra-annular space 94.

[0057] If the annular ring 18 is expandable or otherwise compressed, the annular ring 18 may then be expanded within the biological annulus 90, e.g., to dilate the biological annulus or otherwise direct the surrounding tissue outwardly against the underlying tissue structures. For example, the annular ring 18 may simply be released by the delivery tool, whereupon the annular ring 18 may resiliently expand against the tissue surrounding the biological annulus 90, thereby substantially securing the annular ring 18 (and consequently, the gasket member 12) relative to the biological annulus 90. In addition or alternatively, a dilation tool (not shown) may be advanced into the gasket member 12 and expanded to forcibly (e.g., plastically) expand the annular ring 18 within the biological annulus 90.

[0058] If the sewing ring 20 is restrained by the delivery tool, the sewing ring 20 may be released to allow the sewing ring 20 to contact the surrounding tissue, e.g., within the aortic root above the biological annulus 90. Because of the floppy (i.e., flexible and conformable) nature of the core, the sewing ring 20 may adopt the shape of the surrounding tissue, e.g., lying flatter within the coronary sinus regions, while becoming more vertical adjacent the commissures.

[0059] With the gasket member 12 in place, a plurality of fasteners 96, e.g., clips, staples, sutures, and the like, may be directed through the sewing ring 20 into the tissue surrounding the biological annulus 90 to secure the gasket member 12 relative to the biological annulus 90. In addition or alternatively, a plurality of fasteners (not shown) may be directed through the openings 28 in the base 42 to secure the gasket member 12 relative to the biological annulus 90. Exemplary fasteners and apparatus and methods for delivering them are disclosed in U.S. Publication Nos. 2005/0080454 and 2006/0122634, the entire disclosures of which are expressly incorporated by reference herein.

[0060] To facilitate accessing the sewing ring 20 during delivery of the fasteners 96, local portions of the collar 22 may be at least partially deflected out of the way. For example, the collar 22 may be folded inwardly to move fabric and other obstructions out of the way, e.g., similar to the embodiments disclosed in U.S. Publication No. 2007/0016285, incorporated by reference herein. Thus, the flexibility of the collar 22 may facilitate visual and/or tactile access to one or more portions of the sewing ring 20, whereupon one or more fasteners 96 may be delivered through the accessed portion(s) of the sewing ring 20. After delivering the fastener(s) 96, the collar 22 may be released, whereupon the collar 22 may resiliently return outwardly to its annular shape.

[0061] The valve member 14 may then be advanced into the biological annulus 90, e.g. using another delivery tool or the same tool (not shown) used to deliver the gasket member 12. The valve member 14 may then be secured to the collar 22. For example, as shown in FIG. 5, the valve member 14 may be directed into the recess 23 of the collar 22 such that a lower portion 36 of the frame 32 contacts and directs the tabs 16 radially outwardly. Once the lower portion 36 of the frame 32 passes below the free ends 16a of the tabs 16, the tabs 16 may resiliently return inwardly to capture the lower portion 36 below the free ends 16a. The inwardly biased tabs 16 thereafter prevent the valve member 14 from moving upwardly, because the lower portion 36 of the frame 32 contacts the tabs 16, thereby securing the valve member 14 to the gasket member 12.

[0062] In addition or alternatively, the collar 22 and/or valve member 14 may include other connectors (not shown), e.g., a drawstring, sutures, guide rails, and the like to secure the valve member 14 relative to the collar 22. Exemplary connectors are disclosed in the references incorporated elsewhere herein, e.g., in US Publication Nos. 2006/0195184 and 2006/0235508, or in application Ser. No. 60/746,038, incorporated by reference above.

[0063] Optionally, if the collar 22 and frame 32 are generally circular, it may be possible to rotate the valve member 14 within the collar 22. As the valve member 14 is rotated, the lower portion 36 of the frame 32 may simply slide around under the tabs 16. Thus, the valve member 14 may be rotated to a desired angular orientation within the biological annulus 90.

[0064] Once the valve member 14 is secured, any tools may be removed, and the procedure completed using known methods.

[0065] The collar 22 may support the valve member 14 within a sinus cavity 98 above the biological annulus 90. For example, the spacing of the collar 22 from the annular ring 18 may predispose the valve member 14 within the sinus of Valsalva above an aortic valve site. During implantation, if desired, the valve member 14 may be pressed into the collar 22, whereupon the spring structure 40 may deform, allowing the collar 22 to move axially towards the annular ring 18. When the valve member 14 is released within the sinus cavity 98, the spring structure 40 may resiliently move upwardly away from the biological annulus 90. Thus, the spring structure 40 may be radially soft and flexible, while providing desired axial support for the valve member 14.

[0066] Because the valve member 14 is supported within the sinus cavity 98 in this manner, the valve member 14 may be selected from a larger size than the diameter or other cross-section of the biological annulus 90. For example, it may be possible to select a valve member 14 that is at least about two millimeters (2 mm) larger than the annular ring 18 for aortic valve applications. In addition, the valve member 14 and collar 22 may allow blood to flow around the valve member 14, e.g., to enter the coronary arteries or other vessels (not shown) communicating with the sinus cavity 98. Even though the valve member 14 and collar 22 are larger than the annular ring 18 and biological annulus 90, the sinus cavity 98 may be sufficiently large to allow blood to flow around the valve member 14 and collar 22 into the coronary arteries or other vessels adjacent the biological annulus 90.

[0067] In addition or alternatively, the sewing ring 20 may have a tri-lobular or other shape (not shown) that may avoid obstructing the coronary arteries or other vessels communicating with the sinus cavity 98. Optionally, the sewing ring 20 may include a stiffening structure, e.g., core 25, to maintain perfusion of the coronary arteries or other vessels communicating with the sinus cavity 98.

[0068] If desired, the collar 22 may allow the valve member 14 to be removed from the sinus cavity 98, e.g., to be replaced with a new valve. To remove the valve member 14, a tool may be inserted between the frame 32 and the sidewall 22b, e.g., to deflect the tabs 16 radially outwardly. With the tabs 16 deflected outwardly, the lower portion 36 of the frame 32 may be lifted past the tabs 16, allowing the valve member 14 to be removed from the collar 22. Once the valve member 14 is removed, another valve (not shown) may be introduced and received within the collar 22, as desired.

[0069] It will be appreciated that elements or components shown with any embodiment herein are exemplary for the specific embodiment and may be used on or in combination with other embodiments disclosed herein.

[0070] While the invention is susceptible to various modifications, and alternative forms, specific examples thereof have been shown in the drawings and are herein described in detail. It should be understood, however, that the invention is not to be limited to the particular forms or methods disclosed, but to the contrary, the invention is to cover all modifications, equivalents and alternatives falling within the scope of the appended claims.