Patent Description:
The present invention relates to transcatheter valve prostheses and methods of preventing paravalvular leakage. More specifically, the present invention relates to an anti-paravalvular leakage component integrated on an outer surface of a transcatheter valve prosthesis to seal gaps between a support frame of the prosthesis and native valve tissue.

A human heart includes four heart valves that determine the pathway of blood flow through the heart: the mitral valve, the tricuspid valve, the aortic valve, and the pulmonary valve. The mitral and tricuspid valves are atrioventricular valves, which are between the atria and the ventricles, while the aortic and pulmonary valves are semilunar valves, which are in the arteries leaving the heart. Ideally, native leaflets of a heart valve move apart from each other when the valve is in an open position, and meet or "coapt" when the valve is in a closed position. Problems that may develop with valves include stenosis in which a valve does not open properly, and/or insufficiency or regurgitation in which a valve does not close properly. Stenosis and insufficiency may occur concomitantly in the same valve. The effects of valvular dysfunction vary, with regurgitation or backflow typically having relatively severe physiological consequences to the patient.

Recently, flexible prosthetic valves supported by stent structures that can be delivered percutaneously using a catheter-based delivery system have been developed for heart and venous valve replacement These prosthetic valves may include either self-expanding or balloon-expandable stent structures with valve leaflets attached to the interior of the stent structure. The prosthetic valve can be reduced in diameter, by crimping onto a balloon catheter or by being contained within a sheath component of a delivery catheter, and advanced through the venous or arterial vasculature. Once the prosthetic valve is positioned at the treatment site, for instance within an incompetent native valve, the stent structure may be expanded to hold the prosthetic valve firmly in place. One example of a stented prosthetic valve is disclosed in <CIT>et al. entitled "Percutaneous Placement Valve Stent". Another example of a stented prosthetic valve for a percutaneous pulmonary valve replacement procedure is described in <CIT>and <CIT>, both filed by Tower et al.

Document <CIT> relates to methods and apparatus for endovascular heart valve replacement comprising tissue grasping elements.

Document <CIT> relates to paravalvular leakage detection, sealing, and prevention.

Although transcatheter delivery methods have provided safer and less invasive methods for replacing a defective native heart valve, leakage between the implanted prosthetic valve and the surrounding native tissue is a recurring problem. Leakage sometimes occurs due to the fact that minimally invasive and percutaneous replacement of cardiac valves typically does not involve actual physical removal of the diseased or injured heart valve. Rather, the replacement stented prosthetic valve is delivered in a compressed condition to the valve site, where it is expanded to its operational state within the mitral valve. Calcified or diseased native leaflets are pressed to the side walls of the native valve by the radial force of the stent frame of the prosthetic valve. These calcified leaflets do not allow complete conformance of the stent frame with the native valve and can be a source of paravalvular leakage (PVL). Significant pressure gradients across the valve cause blood to leak through the gaps between the implanted prosthetic valve and the calcified anatomy.

Embodiments hereof are related to anti-paravalvular leakage components coupled to an outer surface of the valve prosthesis to seal gaps between the valve prosthesis and native valve tissue.

Embodiments hereof relate to a transcatheter valve prosthesis including a tubular stent having a compressed configuration for delivery within a vasculature and an expanded configuration for deployment within a native heart, valve, a prosthetic valve component disposed within and secured to the stent, and an anti-paravalvular leakage component coupled to and encircling an outer surface of the tubular stent The anti-paravalvular leakage component includes a plurality of self-expanding segments and an annular sealing element attached to the segments. A first end and a second end of each segment is attached to the outer surface of the tubular stent at spaced apart first and second attachment points, respectively. The anti-paravalvular leakage component has an expanded configuration in which the segments curve radially away from the outer surface of the tubular stent and are oblique to the outer surface of the tubular stent such that a plane defined by each segment is non-perpendicular with respect to a tangential plane of the tubular stent taken through the first and second attachments points.

According to other embodiments hereof, embodiments hereof relate to a transcathctcr valve prosthesis including a tubular stent having a compressed configuration for delivery within a vasculature and an expanded configuration for deployment within a native heart valve, a prosthetic valve component disposed within and secured to the stent, and an anti-paravalvular leakage component coupled to and encircling an outer surface of the tubular stent. The anti-paravalvular leakage component includes a plurality of self-expanding segments and an annular scaling element attached to the segments. A first end and a second end of each segment is attached to the outer surface of the tubular stent at spaced apart first and second attachment points, respectively. The anti-paravalvular leakage component has an expanded configuration in which the segments curve radially away from the outer surface of the tubular stent, and the flexibility of the anti-paravalvular leakage component at the plurality of segments varies around the circumference of the tubular stent when the anti-paravalvular leakage component is in the expanded configuration.

The drawings arc not to scale.

Specific embodiments of the present invention are now described with reference to the figures, wherein like reference numbers indicate identical or functionally similar elements. If utilized herein, the terms "distal" or "distally" refer to a position or in a direction away from the heart and the terms "proximal" and "proximally" refer to a position near or in a direction toward the heart. Although the description of the invention is in the context of treatment of heart valves, the invention may also be used where it is deemed useful in other valved intraluminal sites that arc not in the heart. For example, the present invention may be applied to venous valves as well.

<FIG> depicts an exemplary transcatheter heart valve prosthesis <NUM>. Heart valve prosthesis <NUM> is illustrated herein in order to facilitate description of the methods and devices to prevent and/or repair paravalvular leakage according to embodiments hereof. It is understood that any number of alternate heart valve prostheses can be used with the methods and devices described herein. Heart valve prosthesis <NUM> is merely exemplary and is described in more detail in <CIT>et al.

Heart valve prosthesis <NUM> includes an expandable stent or frame <NUM> that supports a prosthetic valve component within the interior of stent <NUM>. In embodiments hereof, stent <NUM> is self-expanding to return to an expanded deployed state from a compressed or constricted delivery state and may be made from stainless steel, a pseudo-elastic metal such as a nickel titanium alloy or Nitinol, or a so-called super alloy, which may have a base metal of nickel, cobalt, chromium, or other metal. "Self-expanding" as used herein means that a structure/component has a mechanical memory to return to the expanded or deployed configuration. Mechanical memory may be imparted to the wire or tubular structure that forms stent <NUM> by thermal treatment to achieve a spring temper in stainless steel, for example, or to set a shape memory in a susceptible metal alloy, such as Nitinol, or a polymer, such as any of the polymers disclosed in <CIT>. Alternatively, heart valve prosthesis <NUM> may be balloon-expandable as would be understood by one of ordinary skill in the art.

In the embodiment depicted in <FIG>, stent <NUM> of valve prosthesis <NUM> has a deployed asymmetric hourglass configuration including an enlarged first end or section <NUM>, a constriction or waist region <NUM>, and a second end or section <NUM>. Enlarged first section <NUM> has nominal deployed diameter D<NUM>, second section <NUM> has nominal deployed diameter D<NUM>, and constriction region <NUM> has deployed substantially fixed diameter D<NUM>. Each section of stent <NUM> may be designed with a number of different configurations and sizes to meet the different requirements of the location in which it may be implanted. When configured as a replacement for an aortic valve, second section <NUM> functions as an inflow end of heart valve prosthesis <NUM> and extends into and anchors within the aortic annulus of a patient's left ventricle, while first section <NUM> functions as an outflow end of heart valve prosthesis <NUM> and is positioned in the patient's ascending aorta. When configured as a replacement for a mitral valve, enlarged first section <NUM> functions as an inflow end of heart valve prosthesis <NUM> and is positioned in the patient's left atrium, while second section <NUM> functions as an outflow end of heart valve prosthesis <NUM> and extends into and anchors within the mitral annulus of a patient's left ventricle. For example, <CIT> and <CIT>, illustrate heart valve prostheses configured for placement in a mitral valve. Each section of stent <NUM> may have the same or different cross-section which may be for example circular, ellipsoidal, rectangular, hexagonal, rectangular, square, or other polygonal shape, although at present it is believed that circular or ellipsoidal may be preferable when the valve prosthesis is being provided for replacement of the aortic or mitral valve. As alternatives to the deployed asymmetric hourglass configuration of <FIG>, the stent valve support frame may have a symmetric hourglass configuration 102B shown in <FIG>, a generally tubular configuration 102C as shown in <FIG>, or other stent configuration or shape known in the art for valve replacement. Stent <NUM> also may include eyelets <NUM> that extend from first end <NUM> thereof for use in loading the heart valve prosthesis <NUM> into a delivery catheter (not shown).

As previously mentioned, heart valve prosthesis <NUM> includes a prosthetic valve component within the interior of stent <NUM>. The prosthetic valve component is capable of blocking flow in one direction to regulate flow through heart valve prosthesis <NUM> via valve leaflets <NUM> that may form a bicuspid or tricuspid replacement valve. <FIG> is an end view of <FIG> and illustrates an exemplary tricuspid valve having three leaflets <NUM>, although a bicuspid leaflet configuration may alternatively be used in embodiments hereof. More particularly, if heart valve prosthesis <NUM> is configured for placement within a native valve having three leaflets such as the aortic, tricuspid, or pulmonary valves, heart valve prosthesis <NUM> may include three valve leaflets <NUM>. If heart valve prosthesis <NUM> is configured for placement within a native valve having two leaflets such as the mitral valve, heart valve prosthesis <NUM> may include two valve leaflets <NUM>. Valve leaflets <NUM> are sutured or otherwise securely and sealingly attached to the interior surface of stent <NUM> and/or graft material <NUM> which encloses or lines stent <NUM> as would be known to one of ordinary skill in the art of prosthetic tissue valve construction. Referring to <FIG>, leaflets <NUM> are attached along their bases <NUM> to graft material <NUM>, for example, using sutures or a suitable biocompatible adhesive. Adjoining pairs of leaflets are attached to one another at their lateral ends to form commissures <NUM>, with free edges <NUM> of the leaflets forming coaptation edges that meet in area of coaptation <NUM>.

Leaflets <NUM> may be made of pericardial material; however, the leaflets may instead be made of another material. Natural tissue for replacement valve leaflets may be obtained from, for example, heart valves, aortic roots, aortic walls, aortic leaflets, pericardial tissue, such as pericardial patches, bypass grafts, blood vessels, intestinal submucosal tissue, umbilical tissue and the like from humans or animals. Synthetic materials suitable for use as leaflets <NUM> include DACRON® polyester commercially available from Invista North America S. of Wilmington, DE, other cloth materials, nylon blends, polymeric materials, and vacuum deposition Nitinol fabricated materials. One polymeric material from which the leaflets can be made is an ultra-high molecular weight polyethylene material commercially available under the trade designation DYNEEMA from Royal DSM of the Netherlands. With certain leaflet materials, it may be desirable to coat one or both sides of the leaflet with a material that will prevent or minimize overgrowth. It is further desirable that the leaflet material is durable and not subject to stretching, deforming, or fatigue.

Graft material <NUM> may also be a natural or biological material such as pericardium or another membranous tissue such as intestinal submucosa. Alternatively, graft material <NUM> may be a low-porosity woven fabric, such as polyester, Dacron fabric, or PTFE, which creates a one-way fluid passage when attached to the stent. In one embodiment, graft material <NUM> may be a knit or woven polyester, such as a polyester or PTFE knit, which can be utilized when it is desired to provide a medium for tissue ingrowth and the ability for the fabric to stretch to conform to a curved surface. Polyester velour fabrics may alternatively be used, such as when it is desired to provide a medium for tissue ingrowth on one side and a smooth surface on the other side. These and other appropriate cardiovascular fabrics are commercially available from Bard Peripheral Vascular, Inc. of Tempe, Ariz. , for example.

Delivery of heart valve prosthesis <NUM> may be accomplished via a percutaneous transfemoral approach or a transapical approach directly through the apex of the heart via a thoracotomy, or may be positioned within the desired area of the heart via different delivery methods known in the art for accessing heart valves. During delivery, if self-expanding, the prosthetic valve remains compressed until it reaches a target diseased native heart valve, at which time the heart valve prosthesis <NUM> can be released from the delivery catheter and expanded in situ via self-expansion. The delivery catheter is then removed and heart valve prosthesis <NUM> remains deployed within the native target heart valve. Alternatively, heart valve prosthesis <NUM> may be balloon-expandable and delivery thereof may be accomplished via a balloon catheter as would be understood by one of ordinary skill in the art.

<FIG> is a side view illustration of heart valve prosthesis <NUM> implanted within a native heart valve, which is shown in section, having native leaflets LN and corresponding native sinuses SN. When heart valve prosthesis <NUM> is deployed within the valve annulus of a native heart valve, stent <NUM> expands within native valve leaflets LN of the patient's defective valve, retaining the native valve leaflets in a permanently open state. The native valve annulus may include surface irregularities on the inner surface thereof, and as a result one or more gaps or cavities/crevices <NUM> may be present or may form between the perimeter of heart valve prosthesis <NUM> and the native valve annulus. For example, calcium deposits may be present on the native valve leaflets (e.g., stenotic valve leaflets) and/or shape differences may be present between the native heart valve annulus and prosthesis <NUM>. More particularly, in some cases native annuli are not perfectly rounded and have indentations corresponding to the commissural points of the native valve leaflets. As a result, a prosthesis having an approximately circular shape does not provide an exact fit in a native valve. These surface irregularities, whatever their underlying cause, can make it difficult for conventional prosthetic valves to form a blood tight seal between the prosthetic valve and the inner surface of the valve annulus, causing undesirable paravalvular leakage and/or regurgitation at the implantation site.

Embodiments hereof relate to methods for delivering a heart valve prosthesis having a self-expanding anti-paravalvular leakage component thereon that functions to occlude or fill gaps between the perimeter of a heart valve prosthesis and the native valve annulus, thereby reducing, minimizing, or eliminating leaks there through. An anti-paravalvular leakage component <NUM> is shown in <FIG> in its deployed or expanded configuration, extending around an outer surface or perimeter <NUM> of heart valve prosthesis <NUM> to prevent paravalvular leakage in situ. Anti-paravalvular leakage component <NUM> extends in a radially outward direction relative to outer surface <NUM> of heart valve prosthesis <NUM>, and exerts a radial pressure onto a native valve annulus when deployed in situ. More particularly, an expanded or deployed outer diameter of anti-paravalvular leakage component <NUM> is predetermined to be greater than the expanded outer diameter of stent <NUM>. When deployed, anti-paravalvular leakage component <NUM> radially expands into and substantially fills any/all gaps or cavities/crevices between outer surface <NUM> of stent <NUM> and native valve tissue. "Substantially" as utilized herein means that blood flow through the target gap or cavity is occluded or blocked, or stated another way blood is not permitted to flow there through. Anti-paravalvular leakage component <NUM> blocks blood flow around the outer perimeter of prosthesis <NUM>, thereby minimizing and/or eliminating any paravalvular leakage at the implantation site.

More particularly, anti-paravalvular leakage component <NUM> includes a radially-compressible ring or annular scaffold <NUM> (shown in phantom in <FIG>) that is operable to self-expand and an impermeable or semi-impermeable membrane <NUM> that covers or extends over an outer surface of annular scaffold <NUM>. Annular scaffold <NUM> is shown removed from anti-paravalvular leakage component <NUM> in <FIG>. In addition, <FIG> shows annular scaffold <NUM> laid flat out for illustrative purposes, while <FIG> is a cross-sectional view taken along line A-A of <FIG>. Annular scaffold <NUM> has sufficient radial spring force and flexibility to conformingly engage impermeable membrane <NUM> within a native heart valve annulus. Suitable materials for impermeable membrane <NUM> include but are not limited to impermeable or semi-impermeable materials such as a low-porosity woven fabric, such as polyester, Dacron fabric, or PTFE. Porous materials advantageously provide a medium for tissue ingrowth. Further, impermeable membrane <NUM> may be pericardial tissue or may be a knit or woven polyester, such as a polyester or PTFE knit, both of which provide a medium for tissue ingrowth and have the ability to stretch to conform to a curved surface. Polyester velour fabrics may alternatively be used, such as when it is desired to provide a medium for tissue ingrowth on one side and a smooth surface on the other side. Impermeable membrane <NUM> is coupled to annular scaffold <NUM> via sutures or other suitable mechanical connection.

With reference to <FIG>, annular scaffold <NUM> is a sinusoidal patterned ring with a plurality of peaks <NUM>, a plurality of valleys <NUM>, and a plurality of segments <NUM> with peaks <NUM> and valleys <NUM> being formed between a pair of adjacent segments <NUM> as shown in <FIG>. Peaks and valleys <NUM>, <NUM> are bends or turns of the scaffold having opposing orientations. In the embodiment depicted in <FIG>, annular scaffold <NUM> includes six peaks <NUM> and six valleys <NUM>. However, it would be obvious to one of ordinary skill in the art that the annular scaffold may include a higher or lower number of peaks and valleys. For example, <FIG> illustrates an embodiment in which an annular scaffold <NUM> includes eight peaks <NUM> and eight valleys <NUM>. Conformability of the annular scaffold increases with a higher or increased number of peaks and valleys; however, the annular scaffold is more radially-compressible or collapsible for delivery with a lower or decreased number of peaks and valleys. In an embodiment, the annular scaffold includes between four and eighteen pairs of peaks and valleys.

In the embodiment depicted in <FIG>, segments <NUM> bow or curve radially outward while both peaks <NUM> and valleys <NUM> bend or curve radially inward toward stent <NUM>. Outer surface <NUM> of each segment <NUM> is convex, while an inner surface <NUM> of each segment <NUM> is concave. In one embodiment hereof, only peaks <NUM> are coupled to stent <NUM> while valleys <NUM> are unattached or free. In another embodiment hereof, only valleys <NUM> are coupled to stent <NUM> while peaks <NUM> are unattached or free. When only one end of annular scaffold <NUM> is constrained, i.e., either peaks <NUM> or valleys <NUM>, the opposing unattached or free end of the annular scaffold is unconstrained, highly flexible, and has an ability to conform to an outer sheath utilized in deployment thereof. More particularly, the unattached peaks or valleys of the annular scaffold slide or ride along outer surface <NUM> of stent <NUM> when an outer sheath is advanced over the stent to compress/collapse heart, valve prosthesis <NUM> for delivery. By sliding along outer surface <NUM> of stent <NUM>, annular scaffold <NUM> and therefore anti-paravalvular leakage component <NUM> approaches a substantially linear delivery configuration within the outer sheath. When the outer sheath is retracted to deploy heart valve prosthesis <NUM>, the unattached or free peaks or valleys of the annular scaffold return to their preset expanded or deployed shape because annular scaffold <NUM> is formed from a material having a mechanical memory. Mechanical memory may be imparted to annular scaffold <NUM> by thermal treatment to achieve a spring temper in stainless steel, for example, or to set a shape memory in a susceptible metal alloy, such as NiTi (Nitinol). In an alternate embodiment, a mechanical memory to return to the preset expanded or deployed shape may be imparted to a shape memory polymer that forms annular scaffold <NUM>, such as any of the polymers disclosed in <CIT>.

In an embodiment, anti-paravalvular leakage component <NUM> is coupled to heart valve prosthesis <NUM> after manufacture of heart valve prosthesis <NUM>. In another embodiment, anti-paravalvular leakage component <NUM> is manufactured in conjunction with, i.e., at the same time as, heart valve prosthesis <NUM>. Regardless of whether anti-paravalvular leakage component <NUM> is formed concurrently with or subsequent to heart, valve prosthesis <NUM>, annular scaffold <NUM> of anti-paravalvular leakage component <NUM> may be formed from a single, continuous wire that may be solid or hollow and may have a different cross-section and/or size from stent <NUM> of heart valve prosthesis <NUM>. More particularly, in an embodiment, stent <NUM> is formed via laser-cut manufacturing method and therefore a strut of the stent may have a non-circular cross-section, e.g., a square, rectangular, or polygonal cross-section, and a thickness ranging between <NUM>-<NUM> inches (<NUM> inch = <NUM>, <NUM>). Annular scaffold <NUM> may be formed from a single, continuous wire having a circular or round cross-section as shown in <FIG> with a diameter between <NUM>-<NUM> inches. In another embodiment, the cross-section of the wire that forms annular scaffold <NUM> may be an oval, elliptical, rectangular or ribbon-like, or any other suitable shape. By forming annular scaffold <NUM> of a relatively thinner or smaller wire as compared to a strut of stent <NUM>, annular scaffold <NUM> has greater flexibility to conform to the inner surface of the native valve annulus including any surface irregularities that may be present, thereby filling any gaps or cavities/crevices that may be present between the heart valve prosthesis <NUM> and native tissue, while the thicker struts of stent <NUM> provide sufficient radial force to deploy the heart valve prosthesis into apposition with the native valve annulus. In another embodiment hereof, annular scaffold <NUM> of anti-paravalvular leakage component <NUM> may be integrally formed with stent <NUM> of heart valve prosthesis via a laser-cut manufacturing method. If integrally formed with stent <NUM>, the cross-section of the wire/strut of annular scaffold <NUM> may be the same size and shape as a strut of the stent or may be of a different size and/or shape as the strut of the stent.

Shown deployed within an aortic valve in <FIG>, segments <NUM> of annular scaffold <NUM> protrude radially outward from heart valve prosthesis <NUM> to easily conform to calcified anatomy of the native valve while impermeable membrane <NUM> provides a mechanical barrier to the blood flowing through any gaps or cavities/crevices present between the heart valve prosthesis and the native valve tissue. Antegrade blood flow BF is illustrated by directional arrows in <FIG>. Annular scaffold <NUM> is radially and circumferentially compliant due to its relatively small wire size, as described herein. With such maximized conformability, anti-paravalvular leakage component <NUM> functions as a continuous circumferential seal around the heart valve prosthesis to prevent or block blood flow between the outer surface or perimeter of the heart valve prosthesis and a native heart valve annulus.

In the embodiment of <FIG>, anti-paravalvular leakage component <NUM> is coupled to outer surface <NUM> of heart valve prosthesis <NUM> adjacent to second end <NUM> thereof. When deployed, anti-paravalvular leakage component <NUM> may be positioned in situ at the native valve annulus, slightly above the valve annulus, slightly below the valve annulus, or some combination thereof. Since the annular anti-paravalvular leakage component is coupled to outer surface <NUM> of heart valve prosthesis <NUM>, longitudinal placement and/or the size and shape thereof is flexible and may be adjusted or adapted according to each application and to a patient's unique needs. For example, depending on the anatomy of the particular patient, the anti-paravalvular leakage component may be positioned on heart valve prosthesis <NUM> so that in situ the anti-paravalvular leakage component is positioned between heart valve prosthesis <NUM> and the interior surfaces of the native valve leaflets, between heart valve prosthesis <NUM> and the interior surfaces of the native valve annulus, and/or between heart valve prosthesis <NUM> and the interior surfaces of the left ventricular outflow track (LVOT).

The shape or configuration of the annular scaffold may be optimized based on the design and application of the heart valve prosthesis. In another embodiment hereof depicted in <FIG> and <FIG>, an annular scaffold <NUM> includes segments <NUM> that curve or flare radially outward between valleys <NUM> that bend or curve radially inward for attachment to a stent of a heart valve prosthesis and peaks <NUM> that flare or curve radially outward. Outer surface <NUM> of each segment <NUM> is concave, while an inner surface <NUM> of each segment <NUM> is convex. Since only valleys <NUM> are coupled/constrained to the heart valve prosthesis and peaks <NUM> are unconstrained or free and highly flexible, annular scaffold <NUM> has an ability to conform to an outer sheath utilized in deployment thereof as described above.

<FIG> illustrates an anti-paravalvular leakage component <NUM> coupled to heart valve prosthesis <NUM>, which is deployed within an aortic valve having native valve leaflets LN. Anti-paravalvular leakage component <NUM> includes an impermeable membrane <NUM> coupled to an outer surface of annular scaffold <NUM>, thereby forming an open-ended pocket or compartment <NUM> around stent <NUM> between an inner surface of anti-paravalvular leakage component <NUM> and outer surface <NUM> of heart valve prosthesis <NUM>. Open-ended pocket <NUM> catches and blocks any retrograde flow within the aortic valve, thereby preventing undesired regurgitation and preventing blood stagnation in and around the native valve sinuses. In addition, the configuration of anti-paravalvular leakage component <NUM>, formed by flared, unconstrained peaks <NUM> and impermeable membrane <NUM> coupled to the outside surface of the annular scaffold, diverts or deflects antegrade blood flow away from heart valve prosthesis <NUM>. Antegrade blood flow BFA is illustrated with a directional arrow in <FIG>. By diverting or deflecting antegrade blood flow away from the heart valve prosthesis and catching retrograde blood flow with open-ended pocket <NUM>, anti-paravalvular leakage component <NUM> formed with annular scaffold <NUM> functions as a continuous circumferential seal around the heart valve prosthesis to prevent or block blood flow between the outer surface or perimeter of the heart valve prosthesis and a native heart valve annulus.

In yet another embodiment hereof, the anti-paravalvular leakage component may include two or more adjacent annular scaffolds. The adjacent annular scaffolds may have the same configuration, i.e., two adjacent annular scaffold <NUM> or two adjacent annular scaffold <NUM>, or the adjacent annular scaffold may have different configurations. For example, <FIG> illustrates a heart valve prosthesis <NUM> having a first annular scaffold 1032A and a second annular scaffold 1032B. Heart valve prosthesis <NUM> includes a support frame or stent <NUM> and a valve component <NUM> secured therein, but graft material adjacent to a second end <NUM> thereof is not shown for sake of clarity. Annular scaffold 1032A is similar to annular scaffold <NUM> and includes segments that bow or bulge radially outward while both peaks and valleys thereof bend or curve radially inward toward heart valve prosthesis <NUM>. Annular scaffold 1032B is similar to annular scaffold <NUM> and includes segments that are curved or flare radially outward between valleys that bend or curve radially inward for attachment to heart valve prosthesis <NUM> and unconstrained peaks that flare or curve radially outward. Although not shown for sake of clarity, an impermeable membrane is coupled to each of annular scaffolds 1032A, 1032B to form two anti-paravalvular leakage components as described herein with respect to annular scaffolds <NUM>, <NUM>, respectively. In addition, although shown with annular scaffold 1032B adjacent to second end <NUM> of heart valve prosthesis <NUM>, it will be apparent to one of ordinary skill in the art that annular scaffold 1032A may alternatively be located closer to second end <NUM> than annular scaffold 1032B. The adjacent annular scaffolds may be positioned such their peaks and valleys are in phase with each other, or out of phase with each other for improved compressibility/collapsibility.

Although embodiments depicted herein illustrate an anti-paravalvular leakage component integrated onto a heart valve prosthesis configured for implantation within an aortic valve, it would be obvious to one of ordinary skill in the art that an anti-paravalvular leakage component as described herein may be integrated onto a heart valve prosthesis configured for implantation implanted within other heart valves. For example, <FIG> illustrates an anti-paravalvular leakage component <NUM> coupled to the outer surface or perimeter of a heart valve prosthesis <NUM> implanted within a mitral valve.

<FIG> illustrates an anti-paravalvular leakage component <NUM>, in its expanded or deployed configuration, coupled to a heart valve prosthesis <NUM> according to another embodiment hereof. In this embodiment, anti-paravalvular leakage component <NUM> includes a plurality of independent, self-expanding segments <NUM> and an annular sealing element <NUM>. Annular sealing element <NUM> is coupled to inner surfaces <NUM> of segments <NUM>. and when the segments radially expand or deploy as described in more detail herein, annular sealing element <NUM> is positioned between an outer surface <NUM> of heart valve prosthesis <NUM> and inner surfaces <NUM> of the segments. As such, annular sealing element <NUM> extends around the outer surface or perimeter of heart valve prosthesis <NUM> and extends into and substantially fills any/all gaps or cavities/crevices between outer surface <NUM> of heart valve prosthesis <NUM> and native valve tissue to prevent paravalvular leakage in situ. In an embodiment hereof, annular sealing element <NUM> may be formed from a swellable material that collapses easily and expands to a larger volume after implantation, such as but not limited to hydrogel or a collagen foam/sponge similar to the material commercially available under the trademark Angioseal. Other suitable material examples for annular sealing element <NUM> include tissue, compressible foam materials, fabric, or compressible polymeric materials.

Segments <NUM> are coupled to an outer surface <NUM> of heart valve prosthesis <NUM>. More particularly, first and second ends <NUM>, <NUM> of segments <NUM> are coupled to an outer surface <NUM> of heart valve prosthesis <NUM> via welding, sutures, or other suitable mechanical method. In another embodiment hereof, segments <NUM> may be integrally formed with stent <NUM> of heart valve prosthesis. Segments <NUM> are spaced apart in approximately equal intervals or segments around heart valve prosthesis <NUM> as shown in <FIG>, which is an end view taken along line A-A of <FIG>. In another embodiment hereof, the segments may be spaced apart in non-equal intervals or segments around the outside of the heart valve prosthesis. For example, it may be desirable to position one or more segments at a location on the heart valve prosthesis corresponding to an area prone to leakage in situ, such as adjacent to the native valve commissures. Although shown with eight segments <NUM>, it will be understood by one of ordinary skill in the art that a greater or lesser number of segments may be utilized herein.

As best shown in <FIG>, in which annular sealing element <NUM> has been removed for clarity, ends <NUM>, <NUM> of each segment <NUM> are coupled to opposing peaks or apexes of a diamond-shaped opening <NUM> of stent <NUM> of heart valve prosthesis <NUM>. In this embodiment, segments <NUM> are coupled to diamond-shaped openings adjacent to end <NUM> of heart valve prosthesis <NUM> but it will be understood that the segments may be coupled to diamond-shaped openings anywhere along the length of stent <NUM>. The longitudinal position of anti-paravalvular leakage component <NUM> on heart valve prosthesis <NUM> may vary depending upon application and configuration of the heart valve prosthesis. Coupling each segment <NUM> to opposing peaks or apexes of a diamond-shaped opening <NUM> of stent <NUM> allows each segment to utilize the foreshortening of stent <NUM> to its advantage because each segment <NUM> aligns and packs/collapses within its corresponding opening <NUM> when heart valve prosthesis <NUM> is crimped for delivery. More particularly, as shown in <FIG>. when heart valve prosthesis <NUM> is crimped onto a catheter (not shown) for delivery thereof, openings <NUM> are longitudinally stretched and elongate to a length L<NUM>, which is shown in <FIG>. An arc length of each segment <NUM> is approximately equal to length L2, the crimped length of opening <NUM> such that each segment <NUM> is stretched flat or flush over its corresponding opening <NUM> when crimped. Stated another way, each segment <NUM> is straightened when heart valve prosthesis <NUM> is crimped for delivery and the straightened segment <NUM> is in line or flush with the crimped stent <NUM>. When each segment <NUM> is stretched flat or flush over its corresponding opening <NUM>, the material of annular sealing clement <NUM> is compressed and pulled inside stent <NUM> via openings <NUM>. Accordingly, the addition of anti-paravalvular leakage component <NUM> advantageously does not increase, or minimally increases, the packing profile of heart valve prosthesis <NUM> so that heart valve prosthesis <NUM> has the ability to pack in lower profile delivery systems.

When heart valve prosthesis <NUM> is deployed, as shown in <FIG>, stent <NUM> foreshortens and the length of openings <NUM> return to their deployed length L<NUM>, which is shown in <FIG>. Segment <NUM>, and annular scaling member <NUM> attached thereto, self-expand radially outward as shown in <FIG> and <FIG>. An outer surface <NUM> of each segment is convex, while the inner surface <NUM> of each segment is concave. Similar to segments <NUM> of annular scaffold <NUM> described with respect to <FIG> herein, segments <NUM> bow or curve radially outward to easily conform to calcified anatomy of the native valve while annular sealing member <NUM> provides a mechanical barrier to the blood flowing through any gaps or cavities/crevices present between the heart valve prosthesis and the native valve tissue. In this embodiment, since annular sealing member <NUM> is positioned between segments <NUM> and prosthesis <NUM>, the sealing member is protected from being unintentionally moved or shifted during delivery.

Similar to previous embodiments described herein, anti-paravalvular leakage component <NUM> may be formed concurrently with or subsequent to heart valve prosthesis <NUM> and each segment <NUM> of anti-paravalvular leakage component <NUM> may be formed from a wire that may be solid or hollow and may have a different cross-section and/or size from stent <NUM> of heart valve prosthesis <NUM>. For example, segments <NUM> may be formed of a relatively thinner or smaller wire as compared to a strut of stent <NUM> such that anti-paravalvular leakage component <NUM> has greater flexibility to conform to the inner surface of the native valve annulus including any surface irregularities that may be present, thereby filling any gaps or cavities/crevices that may be present between the heart valve prosthesis <NUM> and native tissue, while the thicker struts of stent <NUM> provide sufficient radial force to deploy the heart valve prosthesis into apposition with the native valve annulus.

Segments <NUM> are radially-compressible and self-expanding. In order to self-expand, segments <NUM> may be made from a metallic material having a mechanical memory to return to the preset expanded or deployed shape. Mechanical memory may be imparted to segments <NUM> by thermal treatment to achieve a spring temper in stainless steel, for example, or to set a shape memory in a susceptible metal alloy, such as NiTi (Nitinol) or Co-Cr (Cobalt- Chrome). In an alternate embodiment, a mechanical memory to return to the preset expanded or deployed shape may be imparted to a shape memory polymer that forms segments <NUM>, such as any of the polymers disclosed in <CIT>.

It will be understood by one of ordinary skill in the art that the length of anti-paravalvular leakage component <NUM> is not limited to the embodiment shown in <FIG>. For example, as shown in the embodiment of <FIG>, in which the annular sealing element has been removed for clarity, each segment <NUM> may extend over two openings <NUM> of a stent <NUM> of a heart valve prosthesis <NUM>. Ends <NUM>, <NUM> of each segment <NUM> are coupled to opposing peaks or apexes of two longitudinally-adjacent diamond-shaped opening <NUM>. As explained above, each segment <NUM> aligns and packs/collapses within its corresponding openings <NUM> when heart valve prosthesis <NUM> is crimped for delivery. An arc length of each segment <NUM> is approximately equal to length L<NUM>, the crimped length of two longitudinally-adjacent diamond-shaped openings <NUM>, as shown in <FIG>. When heart valve prosthesis <NUM> is deployed, as shown in <FIG>, stent <NUM> foreshortens and the length of two longitudinally-adjacent diamond-shaped openings <NUM> return to their deployed length L<NUM>, which is shown in <FIG>. Segment <NUM>, and the annular sealing member attached thereto, self-expand or bow radially outward to conform to the anatomy of the native valve.

In addition, two or more anti-paravalvular leakage components may be included on a heart valve prosthesis. For example, <FIG> illustrates a heart valve prosthesis <NUM> having a first anti-paravalvular leakage component 1630A and a second anti-paravalvular leakage component 1630B. Although not shown for sake of clarity, an annular sealing element is coupled inside surfaces of segments 1650A, 1650B to form two anti-paravalvular leakage components 1630A, 1630B, respectively, as described herein with respect to anti-paravalvular leakage component <NUM>. Segments 1650A, 1650B are shown coupled to adjacent rows of openings <NUM> of stent <NUM> such that anti-paravalvular leakage components 1630A, 1630B are abutting against each other, but anti-paravalvular leakage components 1630A, 1630B may alternatively be positioned at longitudinally spaced apart locations on heart valve prosthesis <NUM>.

In the embodiments of <FIG>, segments of the anti-paravalvular leakage components in the expanded configuration are orthogonal to the outer surface of the tubular stent. "Orthogonal" to the outer surface of the tubular stent as used herein means that a plane defined by each expanded segment is perpendicular with respect to a tangential plane of the tubular stent taken through the first and second attachments points. When positioned in situ, deformation of the valve prosthesis by the surrounding native anatomy as an orthogonal force may require straightening of the orthogonal segment and distortion of the tubular stent to which the segment is attached. However, in another embodiment hereof, when the anti-paravalvular leakage component is in the expanded configuration the segments may be oblique to the outer surface of the tubular stent. "Oblique" to the outer surface of the tubular stent as used herein means that a plane defined by each segment is non-perpendicular with respect to a tangential plane of the tubular stent taken through the first and second attachments points. The plane defined by each segment may form an angle between <NUM> and <NUM> degrees with respect to a tangential plane of the outer surface of the tubular stent. When positioned in situ, deformation of the valve prosthesis by the surrounding native anatomy as a non-orthogonal force results in bending or pivoting of the oblique segments at the first and second attachments points, thereby increasing conformability of the anti-paravalvular leakage component with respect to the surrounding native anatomy. Further, since oblique segments bend or pivot rather than flatten to accommodate the surrounding native anatomy, such bending does not distort the tubular stent and the oblique segments may be designed independently of the tubular frame to optimize force and movement thereof for sealing purposes.

More particularly, <FIG> illustrate an embodiment hereof in which an anti-paravalvular leakage component <NUM>, in its expanded or deployed configuration, includes a plurality of independent, self-expanding segments <NUM> that are oblique to an outer surface <NUM> of a tubular stent <NUM> of a heart valve prosthesis <NUM>. Similar to anti-paravalvular leakage component <NUM>, anti-paravalvular leakage component <NUM> includes segments <NUM> and an annular sealing element <NUM>. Segments <NUM> are coupled to outer surface <NUM> of heart valve prosthesis <NUM>, and an outer surface <NUM> of each segment is convex while the inner surface <NUM> of each segment is concave. More particularly, first and second ends <NUM>, <NUM> of segments <NUM> are coupled to an outer surface <NUM> of heart valve prosthesis <NUM> via welding, sutures, or other suitable mechanical method. In another embodiment hereof, segments <NUM> may be integrally formed with stent <NUM> of heart valve prosthesis. In this embodiment, ends <NUM>, <NUM> of each segment <NUM> are coupled to opposing peaks or apexes of a diamond-shaped opening <NUM> of stent <NUM> of heart valve prosthesis <NUM>. Since ends <NUM>, <NUM> of each segment <NUM> are coupled to opposing peaks or apexes of a diamond-shaped opening <NUM>, ends <NUM>, <NUM> are coupled to stent <NUM> at axially spaced apart locations but are not circumferentially spaced apart. In further embodiments that will be described in more detail below, the ends of each segment may be coupled to the stent at axially spaced apart and circumferentially spaced apart locations. Further, in this embodiment, segments <NUM> arc coupled to diamond-shaped openings adjacent to end <NUM> of heart valve prosthesis <NUM> but it will be understood that the segments may be coupled to diamond-shaped openings anywhere along the length of stent <NUM>. The longitudinal position of anti-paravalvular leakage component <NUM> on heart valve prosthesis <NUM> may vary depending upon application and configuration of the heart valve prosthesis.

As best shown in <FIG>, segments <NUM> in the expanded or deployed configuration are oblique to outer surface <NUM> of tubular stent <NUM>. More particularly, each segment <NUM> in the expanded or deployed configuration defines a first plane <NUM>. A second or tangential plane <NUM> of stent <NUM> is taken through the first and second attachments points of ends <NUM>, <NUM> of each segment <NUM>. First plane <NUM> as defined by expanded segment <NUM> forms an angle U with second or tangential plane <NUM> of stent <NUM> and is non-perpendicular with respect to second or tangential plane <NUM> of stent <NUM>. In an embodiment hereof, angle Θ may range between <NUM> and <NUM> degrees. In an embodiment hereof, angle θ may range between <NUM> and <NUM> degrees. As angle θ increases, the radial height or distance of segment <NUM> with respect to the outer surface <NUM> of tubular stent <NUM> increases. More particularly, the angle, height, length, and/or geometry of segment <NUM> are all parameters that may be modified to optimize the stress and/or bending movement experienced by segment <NUM>, as well as the force exerted by segment <NUM>, when segment <NUM> is positioned in situ to accommodate the surrounding native anatomy for sealing purposes. Stated another way, the angle, height, length, and/or geometry of segment <NUM> are parameters that may be modified in order for segment <NUM> to achieve optimal scaling performance in situ.

Segments <NUM> arc spaced apart in approximately equal intervals or segments around heart valve prosthesis <NUM> as shown in <FIG>, which is an end view taken along line A-A of <FIG>. In another embodiment hereof, the segments may be spaced apart in non-equal intervals or segments around the outside of the heart valve prosthesis. For example, as will be explained in more detail herein, it may be desirable to position one or more segments at a location on the heart valve prosthesis corresponding to an area prone to leakage in situ, such as adjacent to the native valve commissures. Although shown with eight segments <NUM>, it will be understood by one of ordinary skill in the art that a greater or lesser number of segments may be utilized herein. Conformability of the anti-paravalvular leakage component increases with a higher or increased number of segments; however, the anti-paravalvular leakage component is more radially-compressible or collapsible for delivery with a lower or decreased number of segments.

As shown in <FIG>, annular scaling element <NUM> is coupled to inner surfaces <NUM> of segments <NUM>, and when the segments radially expand or deploy, annular sealing element <NUM> is positioned between outer surface <NUM> of heart valve prosthesis <NUM> and inner surfaces <NUM> of the segments. As such, annular sealing element <NUM> circumferentially surrounds or extends around the outer surface or perimeter of heart valve prosthesis <NUM> and extends into and substantially fills any/all gaps or cavities/crevices between outer surface <NUM> of heart valve prosthesis <NUM> and native valve tissue to prevent paravalvular leakage in situ. Since annular sealing member <NUM> is positioned between segments <NUM> and prosthesis <NUM>, the sealing member is protected from being unintentionally moved or shifted during delivery. In an embodiment hereof, annular sealing clement <NUM> may be formed from a swellable material that collapses easily and expands to a larger volume after implantation, such as but not limited to hydrogel or a collagen foam/sponge similar to the material commercially available under the trademark Angioseal. Other suitable material examples for annular scaling element <NUM> include tissue, compressible foam materials, fabric, or compressible polymeric materials.

In another embodiment hereof shown in <FIG>, anti-paravalvular leakage component 1730B includes annular sealing element 1760B and oblique segments 1750B. Annular sealing element 1760B is coupled to outer surfaces of segments 1750B to form an impermeable or semi-permeable membrane that covers or extends over segments 1750B. Segments 1750B protrude radially outward from the tubular stent to easily conform to calcified anatomy of the native valve while annular scaling element 1760B provides a mechanical barrier to the blood flowing through any gaps or cavities/crevices present between the heart valve prosthesis and the native valve tissue. Since annular sealing member 1760B is positioned over segments 1750B, the sealing member advantageously does not increase, or minimally increases, the packing profile of the heart valve prosthesis so that the heart valve prosthesis has the ability to pack in lower profile delivery systems. Suitable materials for annular sealing element 1760B include but are not limited to impermeable or semi-permeable materials such as a low-porosity woven fabric, such as polyester, Dacron fabric, or PTFE. Porous materials advantageously provide a medium for tissue ingrowth. Further, annular scaling element 1760B may be pericardial tissue or may be a knit or woven polyester, such as a polyester or PTFE knit, both of which provide a medium for tissue ingrowth and have the ability to stretch to conform to a curved surface. Polyester velour fabrics may alternatively be used, such as when it is desired to provide a medium for tissue ingrowth on one side and a smooth surface on the other side. Annular sealing element 1760B is coupled to segments 1750B via sutures or other suitable mechanical connection.

In another embodiment hereof, the graft material of the heart valve prosthesis may form the annular sealing element of the anti-paravalvular leakage component. More particularly, as shown in the embodiment of <FIG>, anti-paravalvular leakage component 1730C includes oblique segments 1750C which are coupled or attached to graft material 1706C which encloses or lines stent 1702C of the heart valve prosthesis. For example, segments 1750C may be stitched to graft material 1706C. In one embodiment, graft material 1706C may be selected so as to have the ability to stretch during deployment of the heart valve prosthesis. In another embodiment, the heart valve prosthesis may be configured with extra or additional graft material 1706C, e.g., folds, which may be pulled out during deployment of the heart valve prosthesis. When deployed, graft material 1706C which is coupled to segments 1750C is pulled radially away from the outer surface of stent 1702C such that the graft material forms an impermeable or semi-permeable membrane that provides a mechanical barrier to the blood flowing through any gaps or cavities/crevices present between the heart valve prosthesis and the native valve tissue. When graft material 1706C lines stent 1702C, and thus is coupled to an inside surface thereof, graft material 1706C may be pulled through the diamond-shaped openings or cells formed within stent 1702C. Since the graft material of the heart valve prosthesis forms the annular sealing member, this embodiment advantageously does not increase the packing profile of the heart valve prosthesis so that the heart valve prosthesis has the ability to pack in lower profile delivery systems.

The oblique self-expanding segments of <FIG> may have other configurations, and the size, shape, or configuration of the annular scaffold may be optimized based on the design and application of the heart valve prosthesis. <FIG> illustrate various exemplary configurations for oblique self-expanding segments utilized in embodiments hereof. For example, <FIG> depicts a plurality of independent, self-expanding segments <NUM> that arc oblique to an outer surface <NUM> of a tubular stent <NUM>. In <FIG>, the annular scaling component of the anti-paravalvular leakage component has been removed for clarity. Similar to previous embodiments, first and second ends <NUM>. <NUM> of segments <NUM> are coupled to or formed integrally with an outer surface <NUM> of tubular stent <NUM>. In this embodiment, however, ends <NUM>, <NUM> of each segment <NUM> arc not coupled to opposing peaks or apexes of a diamond-shaped opening <NUM> of stent <NUM> but rather are coupled to adjacent or consecutive sides of the diamond-shaped opening <NUM>. Accordingly, the length or size of segments <NUM> arc shorter or less than the length or size of segments <NUM>. Ends <NUM>. <NUM> are coupled to stent <NUM> at axially-spaced apart locations but are not circumferentially spaced apart. In this embodiment, segments <NUM> are coupled to adjacent sides of the right half or portion of diamond-shaped opening <NUM>, but it will be understood that the segments may be coupled to the opposing or left half of the diamond-shaped opening as shown in <FIG>, which are front and side views of an isolated diamond-shaped opening <NUM> of a stent, illustrate another embodiment hereof in which an oblique self-expanding segment <NUM> is coupled to adjacent or consecutive sides on the left half or portion of the diamond-shaped opening <NUM>. Ends <NUM>, <NUM> of segment <NUM> are coupled to diamond-shaped opening <NUM> at axially-spaced apart locations but are not circumferentially spaced apart. Segment <NUM> is shown in its expanded or deployed configuration.

<FIG>, which are front and side views of an isolated diamond-shaped opening <NUM> of a stent, illustrate another embodiment hereof in which an oblique self-expanding segment <NUM> is coupled to opposing peaks or apexes of a diamond-shaped opening <NUM>. In this embodiment, however, only a middle portion <NUM> of segment <NUM> bends or curves radially away from the outer surface of the tubular stent rather than the full or entire length of the segment Accordingly, the length or size of the radially-extending portions, i.e., middle portions <NUM>, of segments <NUM> is shorter or less than the full length or size of segments <NUM>. Ends <NUM>, <NUM> of segment <NUM> are coupled to diamond-shaped opening <NUM> at axially-spaced apart locations but are not circumferentially spaced apart. Segment <NUM> is shown in its expanded or deployed configuration.

According to the invention, the attachment points of the segments are positioned on peaks of diamond-shaped openings formed within the tubular stent.

<FIG>, which are front and side views of an isolated diamond-shaped opening <NUM> of a stent, illustrate an oblique self-expanding segment <NUM> that is coupled to diagonallyopposing sides of a diamond-shaped opening <NUM>. Ends <NUM>, <NUM> of segment <NUM> are coupled to diamond-shaped opening <NUM> at axially spaced apart locations and circumferentially spaced apart locations. Segment <NUM> is shown in its expanded or deployed configuration.

<FIG>, which are front and side views of an isolated diamond-shaped opening <NUM> of a stent, illustrate an oblique self-expanding segment <NUM> that is coupled to adjacent or consecutive sides of a diamond-shaped opening <NUM>. In this example, however, a middle portion <NUM> of segment <NUM> has a different curvature than the remaining length of the segment Stated another way, middle portion <NUM> of segment <NUM> includes an additional bump or bulge along the length of segment <NUM>. Ends <NUM>, <NUM> of segment <NUM> are coupled to diamond-shaped opening <NUM> at axially-spaced apart locations but are not circumferentially spaced apart. Segment <NUM> is shown in its expanded or deployed configuration,
<FIG>, which are front and side views of an isolated diamond-shaped opening <NUM> of a stent, illustrate an oblique self-expanding segment <NUM> that is coupled to diagonallyopposing sides of a diamond-shaped opening <NUM>. In this example, segment <NUM> has a sinusoidal or wavy configuration along the length thereof. Ends <NUM>, <NUM> of segment <NUM> are coupled to diamond-shaped opening <NUM> at axially spaced apart locations and circumferentially spaced apart locations. Segment <NUM> is shown in its expanded or deployed configuration.

<FIG>, which are front and side views of an isolated diamond-shaped opening <NUM> of a stent, illustrate an oblique self-expanding segment <NUM> that is U-shaped and coupled to opposing sides of a diamond-shaped opening <NUM>. Ends <NUM>, <NUM> of segment <NUM> are coupled to diamond-shaped opening <NUM> at circumferentially spaced apart locations but not axially spaced apart locations. Segment <NUM> is shown in its expanded or deployed configuration. U-shaped as used herein includes segments having two opposing side portions 2463A, 2463B with ends that converge together from a bottom or apex curved portion <NUM>. As will be understood by those of ordinary skill in the art, "side" and "bottom" are relative terms and utilized herein for illustration purposes only. The two opposing side portions 2463A, 2463B of the U-shaped segment <NUM> may be slanted or angled relative to each other, as shown in <FIG>, or may extend parallel to each other. Further, the U-shaped segment <NUM> may be considerably longer, shorter, wider, or narrower than shown. As best shown in the side view of <FIG>, U-shaped segment <NUM> flares radially outward such that bottom or apex curved portion <NUM> is most radially spaced away from the stent. An outer surface <NUM> of U-shaped segment <NUM> is concave, while an inner surface <NUM> of U-shaped segment <NUM> is convex. However, the U-shaped segment may have other expanded or deployed configurations such as the one shown in <FIG>, which are front and side views of an isolated diamond-shaped opening <NUM> of a stent, illustrate an oblique self-expanding segment <NUM> that is U-shaped and coupled to opposing sides of a diamond-shaped opening <NUM>. Ends <NUM>, <NUM> of segment <NUM> are coupled to diamond-shaped opening <NUM> at circumferentially spaced apart locations but not axially spaced apart locations. Segment <NUM> is shown in its expanded or deployed configuration. U-shaped segment <NUM> curves radially outward such that at least portions of opposing side portions 2563A, 2563B as well as bottom curved portion <NUM> are most radially spaced away from the stent An outer surface <NUM> of U-shaped segment <NUM> is convex, while an inner surface <NUM> of U-shaped segment <NUM> is concave.

<FIG>, which are front and side views of two isolated diamond-shaped openings <NUM> A, 2658B of a stent, illustrate an oblique self-expanding segment <NUM> that is U-shaped and coupled to adjacent sides of diamond-shaped openings 2658A, 2658B. Ends <NUM>, <NUM> of segment <NUM> are coupled to and span across diamond-shaped openings 2658A, 2658B at circumferentially spaced apart locations but not axially spaced apart locations. Segment <NUM> is shown in its expanded or deployed configuration. As best shown in the side view of <FIG>, U-shaped segment <NUM> flares radially outward such that bottom or apex curved portion <NUM> is most radially spaced away from the stent similar to U-shaped segment <NUM> described above. However, the U-shaped segment may have other expanded or deployed configurations such as the one shown in <FIG>, which are front and side views of two isolated diamond-shaped openings 2758A, 2758B illustrate an oblique self-expanding segment <NUM> that is U-shaped and U-shaped segment <NUM> curves radially outward such that at least portions of opposing side portions 2763A, 2763B as well as bottom curved portion <NUM> are most radially spaced away from the stent similar to U-shaped segment <NUM> described above.

<FIG>, which are front and side views of two isolated diamond-shaped openings 2858A, 2858B of a stent, illustrate another embodiment hereof in which an oblique self-expanding segment <NUM> is coupled to adjacent peaks or apexes of diamond-shaped openings 2858A, 2858B. Ends <NUM>, <NUM> of segment <NUM> are coupled to and span across diamond-shaped openings 2858A, 2858B at circumferentially spaced apart locations but not axially spaced apart locations. Segment <NUM> is shown in its expanded or deployed configuration.

<FIG>, which are front and side views of two isolated diamond-shaped openings 2958A, 2958B of a stent, illustrate another embodiment hereof in which an oblique self-expanding segment <NUM> is coupled to adjacent peaks or apexes of diamond-shaped openings 2958A, 2958B. In this embodiment, however, only a middle portion <NUM> of segment <NUM> extends radially away from the outer surface of the tubular stent rather than the full or entire length of the segment Ends <NUM>, <NUM> of segment <NUM> are coupled to and span across diamond-shaped openings 2958A, 2958B at circumferentially spaced apart locations but not axially spaced apart locations. Segment <NUM> is shown in its expanded or deployed configuration. Middle portion <NUM> may be oriented to extend or curve away from diamond-shaped openings 2958A, 2958B as shown in <FIG>. In another embodiment hereof, shown in <FIG>, a middle portion <NUM> of an oblique self-expanding segment <NUM> may be oriented to extend or curve towards diamond-shaped openings 3058A, 3058B.

<FIG> illustrate two oblique self-expanding segments <NUM> that are coupled to a single diamond-shaped opening <NUM> of a stent <NUM>. <FIG> is an enlarged view of a portion of stent <NUM>, with each diamond-shaped opening <NUM> including two oblique self-expanding segments <NUM>. In <FIG>, the annular sealing component of the anti-paravalvular leakage component has been removed for clarity. <FIG> are front and side views of an isolated diamond-shaped opening <NUM> of stent <NUM>. Ends <NUM>, <NUM> of each segment <NUM> are coupled to adjacent or consecutive sides of diamond-shaped opening <NUM> at axially spaced apart locations and circumferentially spaced apart locations. Segments <NUM> are shown in their expanded or deployed configuration. Providing two oblique segments that extend over one diamond-shaped opening of the tubular stent provides additional structure or support for the anti-paravalvular leakage component, and conformability of the anti-paravalvular leakage component increases due to the higher or increased number of segments. The anti-paravalvular leakage component may include two segments extending over each diamond-shaped opening around the circumference of the tubular stent as shown in <FIG>, or may include two segments extending over select diamond-shaped openings around the circumference of the tubular stent For example, it may be desirable to position two segments extending over select diamond-shaped openings at a location on the heart valve prosthesis corresponding to an area prone to leakage in situ, such as adjacent to the native valve commissures.

In addition, similar to described above with respect to <FIG>, two or more anti-paravalvular leakage components may be included on a heart valve prosthesis. <FIG> illustrates a stent <NUM> for a heart valve prosthesis, the stent including a first anti-paravalvular leakage component 3330A and a second anti-paravalvular leakage component 3330B. Although not shown for sake of clarity, an annular sealing element is coupled to segments 3350A, 3350B to form two anti-paravalvular leakage components 3330A, 3330B, respectively. Segments 3350A, 3350B are oblique to an outer surface <NUM> of tubular stent <NUM>, and are shown coupled to adjacent rows of diamond-shaped openings <NUM> of stent <NUM> such that anti-paravalvular leakage components 3330A, 3330B are abutting against each other. In another embodiment hereof (now shown), anti-paravalvular leakage components 3330A, 3330B may alternatively be positioned at longitudinally spaced apart locations on tubular stent <NUM>.

In embodiments hereof, it may be desirable for the flexibility or conformability of the anti-paravalvular leakage component at the plurality of segments to vary around the circumference of the tubular stent when the anti-paravalvular leakage component is in the expanded configuration. For example, it may be desirable to have one or more segments with increased flexibility or conformability (and lower radial force) over select diamond-shaped openings at a location on the heart valve prosthesis such that the segment(s) may better conform to the inner surface of the native valve annulus including any surface irregularities that may be present, thereby filling any gaps or cavities/crevices that may be present between the heart valve prosthesis and native tissue. Conversely, segments with less flexibility or conformability provide sufficient radial force to deploy the anti-paravalvular leakage component into apposition with the native valve annulus. Thus, the anti-paravalvular leakage component may be modified to have at least one segment having lower radial force and greater flexibility to better accommodate the surrounding native anatomy while maintaining high radial force and apposition in the rest of the anti-paravalvular leakage component. Stated another way, the anti-paravalvular leakage component may be considered to have regions or zones having greater flexibility and less radial force as compared to the rest of the anti-paravalvular leakage component. In addition, zones or sections of differing flexibility and radial force may be configured to minimize impingement of the conduction system. More particularly, the force exerted or applied by the segments may be varied to circumferentially to reduce the force applied to the vessel wall and thus minimize impingement of the conduction system.

According to an embodiment hereof, in order to accomplish the zones or sections of differing flexibility and radial force, the number or frequency of self-expanding segments may be varied over select diamond-shaped openings at a location on the heart valve prosthesis corresponding to an area prone to leakage in situ. Conformability of the anti-paravalvular leakage component increases at the locations on the heart valve prosthesis having a higher or increased number of segments. In one embodiment hereof, the number or frequency of the segments is the highest at portions of the tubular stent that are prone to leakage in situ, such as adjacent to the native valve commissures or adjacent to areas having relatively greater levels of calcification. More particularly, as shown for example in <FIG>. anti-paravalvular leakage component <NUM> for a tubular stent <NUM> that includes a plurality of oblique self-expanding segments 3450A, 3450B and an annular scaling element <NUM> coupled to an outside surface of the segments. Segments 3450A arc similar to segments <NUM> described above in that two segments 3450A extend over a single diamond-shaped opening of tubular stent <NUM>, while segments 3450B are single segments extending over a single diamond-shaped opening of tubular stent <NUM>. In one embodiment hereof, segments 3450A are positioned or located at portions of tubular stent <NUM> that are prone to leakage in situ, such as adjacent to the native valve commissures.

According to another embodiment hereof, the configurations of self-expanding segments may be varied in order to accomplish the zones or sections of differing flexibility and radial force. More particularly, various properties and/or designs of the self-expanding segments may be varied in order to selectively increase or decrease the flexibility or conformability of a particular segment. The plurality of segments may have different oblique angles, sizes or lengths, shapes or designs, and/or may be formed with different thicknesses in order to selectively increase or decrease the flexibility or conformability of a particular segment. For example, decreasing the angle of an oblique segment relative to the outer surface of the stent generally increases flexibility and conformability of the segment. In comparison, increasing the angle of an oblique segment results in less flexibility but greater radial force to ensure that the anti-paravalvular leakage component seals against the native anatomy. In another example, increasing the length of the segment generally increases flexibility and conformability of the segment. In comparison, shorter segments arc less flexible but provide greater radial force. In another example, decreasing the thickness of the segment or a portion of the segment generally increases flexibility and conformability of the segment. In comparison, thicker segments are less flexible but provide greater radial force. In another example, material of the segment, i.e., spring steel verses Nitinol, may selectively impact the flexibility thereof. Other variations or modifications of the segments may be used to provide the anti-paravalvular leakage component with zones with different flexibilities, including but not limited to selecting any of the different shapes or designs of oblique segments described herein for its particular flexibility properties.

Claim 1:
A transcatheter valve prosthesis (<NUM>) and comprising:
a stent (<NUM>) having a compressed configuration for delivery within a vasculature and an expanded configuration for deployment within a native heart valve, wherein the stent (<NUM>) is self-expanding to return to the expanded configuration from the compressed configuration;
a prosthetic valve component disposed within and secured to the stent (<NUM>); and
an anti-paravalvular leakage component (<NUM>) coupled to and encircling an outer surface of the tubular stent (<NUM>), the anti-paravalvular leakage component (<NUM>) including a plurality of self-expanding segments (<NUM>) and an annular sealing element (<NUM>) attached to the segments (<NUM>), the ends of the segments (<NUM>) being attached to the outer surface of the tubular stent (<NUM>) at attachment points, wherein the anti-paravalvular leakage component (<NUM>) has an expanded configuration in which the segments (<NUM>) curve radially away from the outer surface (<NUM>) of the tubular stent (<NUM>),
wherein the attachment points of the segments (<NUM>) are positioned on peaks of diamond-shaped openings formed within the tubular stent (<NUM>).