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`U8008323336BZ
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`(12) United States Patent:
`Hill et a1.
`
`US 8,323,336 B2
`(10) Patent No.:
`(45) Date of Patent:
`Dec. 4, 2012
`
`
`(54) PROSTHETIC HEART VALVE DEVICES AND
`METHODS OF VALVE REPLACEMENT
`
`(56)
`
`References Cited
`
`Us, PATENT DOCUMENTS
`
`(75)
`
`Inventors: Alexander J. Hill, Blaine, MN (US);
`Cynthia T. Clague, Minnetonka, MN
`(US); Carol Elsa Eberhardt, Fullerton,
`CA (US); Ana R. Menk, Minneapolis,
`MN (US); Mark J. Capps, Mission
`Wejo, CA (US); Billie J. Millwee,
`Fullerton, CA (US); Janice Lynn Shay,
`Lake Forest, CA (US); Debra Ann
`Taitague, Orange, CA (US); Joseph C.
`Morrow, Fridley, MN (US); Jerald
`Redmond, Blaine, MN (US)
`
`(73) Assignec: Medtronic,lnc.,Minneapolis,MN(US)
`
`( * ) Notice:
`
`Subject to any disclaimer, the term of this
`patent is extended or adjusted under 35
`[ISO 154(1)) by 342 days.
`
`(21) Appl.No.: 12/429,054
`
`(22) Filed:
`
`Apr. 23, 2009
`
`(65)
`
`Prior Publication Data
`
`US 2009/0281618 A1
`
`Nov. 12, 2009
`
`Related US. Application Data
`
`(60) Provisional application No. 61/1 25,235, filed on Apr.
`23, 2008.
`
`(51)
`
`Int. Cl.
`(2006.01)
`A61F 2/24
`(52) US. Cl.
`...................................... 623/114; 623/124
`(58) Field of Classification Search ........................ None
`See application file for complete search history.
`
`7/2001 Taylor ........................ 623723.64
`6,254,642 131*
`11/2004 Snydcrs
`6,821,297 132
`9/2005 Sedransk ..................... 523/212
`6,945,996 132*
`7,635,386 131* 12/2009 Gammie ...................... 623/211
`7,704,277 132
`4/2010 Zakayetal.
`2004/0210303 Al” 10/2004 Sedransk ....................... 623/21
`2004/0210304 AH 10/2004 Seguin an
`523/211
`2005/0203616 A1
`9/2005 Cribier
`200610195183 A1 *
`{2006 Navia et a1.
`.................. 623/218
`2007/0118154 A1*
`5/2007 Crabtree ....................... 606/151
`
`(Continued)
`
`DE
`
`FOREIGN PA'I‘EN'I‘ DOCUMENTS
`200 03 874
`61’2000
`
`(Continued)
`OTHER PUBLICATIONS
`
`Bolling, ct 01., “Mitral Valve Reconstruction in the Patient with Heart
`Failure," Heart Failure Reviews, 6, 177-185, 2001.
`
`(Continued)
`Primary Examiner ~— Christopher D Koharski
`Assismm Examiner - Rebecca Straszheim
`
`ABSTRACT
`(57)
`A stented valve of two or more leaflets made of pericardium
`or other material having a relatively thin profile at the annu—
`lus. The leaflet surfaces are attached via chords to a stent
`frame, where the chords are positioned to mimic the native
`valve anatomy and functionality. In particular, the valves of
`one exemplary embodiment of the invention are sized to
`replace a mitral valve and therefore the chords are arranged to
`prevent prolapse of the leaflets into the atrium. The stented
`valve has a relatively short height at its annulus due to the
`positioning of the chords In addition, the stented valve is
`capable ofbeing crimped to a small enough size that it can be
`delivered to the implantation site via transcathcter delivery
`systems and methods,
`
`15 Claims, 3 Drawing Sheets
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`

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`US 8,323,336 B2
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`Page 2
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`U.S. PATENT DOCUMENTS
`2007/0173932 A1
`7/2007
`2008/0147183 A1*
`6/2008
`2008/0208328 A1
`8/2008
`2009/0005863 A1
`1/2009
`2009/0276040 A1
`11/2009
`2009/0281618 A1
`11/2009
`2009/0306768 A1
`12/2009
`2009/0319037 A1
`12/2009
`2010/0030330 A1
`2/2010
`2010/0036479 A1
`2/2010
`2010/0042147 A1
`2/2010
`2010/0217382 A1
`8/2010
`
`Call et a1
`S
`c
`‘
`A2,:
`"."'t"'1"""""""""
`06“ 3 1a -
`Gm” et a -
`Rowe et :11.
`Hill et31~
`Quadri
`Rowe or a].
`Bobo et al.
`Hi“ 61 ill-
`Janowsky Ct al.
`C113“ 6t 31-
`FOREIGN PATENT DOCUMENTS
`4/2005
`10010074
`102007043830
`4/2009
`
`DE
`DE
`
`623/2 12
`'
`
`WO
`
`WO
`WO
`WO
`wo
`wo
`
`2005/067821
`
`7/2005
`
`3/2006
`2006/027499
`6/2007
`2007/071436
`3/2008
`2008/028569
`3/2009
`2009/033459
`4/2009
`2009/053497
`OTHER PUBLICATIONS
`
`Luzonschi, el al., “Transapical Milral Valved Stenl Implantation,”
`Ann. Thorac, Surg., 2008;86:745-8.
`Ma, et al., “Double-crowned valved stents for ofl-pump mitral valve
`replacement," Europ. J . ofCardio-thoracic Surg., 28 (2005) 194-199.
`Massana, et al., “Conservative Surgery of the Mitral Valve.
`Annuloplasty on a new Adjustable Ring." Cardiovasscular Surgery
`1980, 1987: 30-37.
`
`* cited by examiner
`
`NORRED EXHIBIT 2229 - Page 2
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`US. Patent
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`Dec. 4, 2012
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`US 8,323,336 132
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`US. Patent
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`Dec. 4, 2012
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`US. Patent
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`Dec. 4, 2012
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`US 8,323,336 B2
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`1
`PROSTIIETIC HEART VALVE DEVICES AND
`METHODS OF VALVE REPLACEMENT
`
`CROSS-REFERENCE TO RELATED
`APPLICATION
`
`This application claims the benefit under 35 U.S.C. §119
`(e) of U.S. Provisional Patent Application No. 61/125,235,
`filed Apr. 23, 2008, which is incorporated herein by reference
`in its entirety.
`
`TECHNICAL FIELD
`
`The present invention relates generally to devices and
`methods for repair of heart valves, and more particularly to
`prosthetic heart valves for use in replacement of the mitral
`valve.
`One of the two atrio-ventricular valves in the heart is the
`mitral valve, which is located on the left side of the heart and
`which forms or defines a valve annulus and valve leaflets. The
`mitral valve is located between the left atrium and the lefi
`ventricle, and serves to direct oxygenated blood from the
`lungs through the left side of the heart and into the aorta for
`distribution to the body. As with other valves of the heart, the
`mitral valve is a passive structure in that it does not itself
`expend any energy and does not perform any active contrac-
`tile firnction.
`The mitral valve includes two moveable leaflets that open
`and close in response to differential pressures on either side of
`the valve. Ideally, the leaflets move apart from each other
`when the valve is in an open position, and meet or “coapt”
`when the valve is in a closed position. However, problems can
`develop with valves, which can generally be classified as
`either stenosis, in which a valve does not open properly, or
`insufficiency (also called regurgitation), inwhich a valve does
`not close properly. Stenosis and insufficiency may occur con—
`com itantly in the same valve. The effects ofvalvular dysfunc-
`tion vary, with mitral regurgitation or backflow typically hav-
`ing relatively severe physiological consequences to the
`patient. Regurgitation, along with other abnormalities of the
`mitral valve, can increase the workload placed on the heart.
`The severity of this increased stress on the heart and the
`patient, and the heart’s ability to adapt to it, determine the
`treatment options that are available for a particular patient. In
`some cases, medication can be sufficient to treat the patient,
`which is the preferred option when it is viable; however, in
`many cases, defective valves have to be repaired or com-
`pletely replaced in order for the patient to live a normal life.
`One situation where repair of a mitral valve is often viable
`is when the defects present in the valve are associated with
`dilation of the valve annulus, which not only prevents com-
`petence ofthe valve but also results in distortion ofthe normal
`shape of the valve orifice. Remodeling of the annulus is
`central to these types of reconstructive procedures on the
`mitral valve. When a mitral valve is repaired, the result is
`generally a reduction in the size of the posterior segment of
`the mitral valve annulus. As a part of the mitral valve repair,
`the involved segment of the annulus is diminished (i.e., con-
`stricted) so that the leaflets may coapt correctly on closing,
`and/or the annulus is stabilized to prevent post-operative dila-
`tation from occurring. Either result is frequently achieved by
`the implantation of a prosthetic ring or band in the supra
`annular position. The purpose ofthe ring or band is to restrict,
`remodel and/or support the annulus to correct and/or prevent
`valvular insufliciency. Such repairs of the valve, when tech-
`nically possible, can produce relatively good long-term
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`However, valve repair is sometimes either impossible or
`undesirable or has failed, such as in cases where dilation of
`the valve annulus is not the problem, leaving valve replace-
`ment as the preferred option for improving operation of the
`mitral valve. In cases where the mitral valve is replaced, the
`two general categories ofvalves that are available for implan-
`tation are mechanical valves and bioprosthctic or tissue
`valves. Mechanical valves have been used'for many years and
`encompass a wide variety of designs that accommodate the
`blood flow requirements ofthe particular location where they
`will be implanted. Although the materials and design features
`of these valves are continuously being improved, they do
`increase the risk of clotting in the blood stream, which can
`lead to a heart attack or stroke. Thus, mechanical valve recipi-
`ents must take anti—coagulant drugs for life to prevent the
`formation of thrombus. On the other hand, the use of tissue
`valves provide the advantage of not requiring anti-coagulant
`drugs, although they do not
`typically last as long as a
`mechanical valve. Traditionally, either type ofvalve has been
`implanted using a surgical procedure that involves opening
`the patient’s chest to access the mitral valve through the left
`atrium, and sewing the new valve in position. This procedure
`is very invasive, carries risks of infection and other compli-
`cations, and requires a lengthy period of recovery for the
`patient.
`'
`To simplify surgical procedures and reduce patient trauma,
`there has been a recent increased interest in minimally inva-
`sive and percutaneous replacement of cardiac valves.
`Replacement of a heart valve in this way typically does not
`involve actual physical removal of the diseased or injured
`heart valve. Rather, a replacement valve is delivered in a
`compressed condition to the valve site, where it is expanded
`to its operational state. One example of such a valve replace—
`ment system includes inserting a replacement pulmonary
`valve into a balloon catheter and delivering it percutaneously
`via the vascular system to the location of a failed pulmonary
`valve. There, the replacement valve is expanded by a balloon
`to compress the native valve leaflets against the right ven-
`tricular outflow tract, thereby anchoring and sealing the
`replacement valve. In the context ofpercutaneous, pulmonary
`valve replacement, U.S. Patent Application Publication Nos.
`2003/0199971 A1 and 2003/0199963 A1, both filed by
`Tower, et al., describe a valved segment of bovine jugular
`vein, mounted within an expandable stent, for use as a
`replacement pulmonary valve. As described in the articles:
`“Percutaneous Insertion of the Pulmonary Valve,” Bonhoef-
`fer, et al., Journal of the American College of Cardiology
`2002; 39: 1664-1669 and “Transcatheter Replacement of a
`Bovine Valve in Pulmonary Position,” Bonhoeffer, et al., Cir-
`culation 2000; 102: 813-816, the replacement pulmonary
`valve may be implanted to replace native pulmonary valves or
`prosthetic pulmonary valves located in valved conduits.
`Other implantables and implant delivery devices also are
`disclosed in published U.S. Patent Application Publication
`No. 2003/0036791 A1 and European Patent Application No.
`1 057 460-AI.
`.
`Due to the different physical characteristics of the mitral
`valve as compared to the pulmonary valve, percutaneous
`implantation of a valve in the mitral position has its own
`unique requirements for valve replacement. There is a con—
`tinued desire to be able to be able to improve mitral valve
`replacement devices and procedures to accommodate the
`physical structure of the heart without causing undue stress
`during operation of the heart, such as providing devices and
`NORRED EXHIBIT 2229 - Page 6
`methods for replacing the mitral valve percutaneously.
`
`SUMMARY
`
`One embodiment of the invention includes a pericardial
`
`

`

`US 8,323,336 82
`
`3
`replicates the native atrioventricular valve anatomy. This is
`accomplished by constructing a valve oftwo or more leaflets
`made ofpericardium or other material having a relatively thin
`profile at the annulus. The artificial chordae can be con-
`structed of ePTFE, for example, and can be attached in a
`variety ofmanners to the leaflets. These chords are positioned
`to mimic the native valve anatomy and functionality. In par-
`ticular, the valves ofone exemplary embodiment ofthe inven-
`tion are sized to replace a mitral valve and therefore the
`chords are arranged to prevent prolapse ofthe leaflets into the 10
`atrium.
`
`5
`
`The pericardial valve design of the invention advanta—
`geously provides a stented valve having a relatively short
`height at its annulus due to the positioning of the chords. In
`addition, the stented valves are capable ofbeing crimped to a 15
`small enough size that they can be delivered to the implanta~
`tion site via transcatheter delivery systems and methods.
`The stents used for the stented valves of the invention can
`be compressible and expandable stents for implantation into
`a body lumen, such as for replacement ofone ofthe atrioven- 20
`tricular valves. The stent of one embodiment of these stented
`valves comprises a frame having a central annular region,
`atrial flares extending from one side ofthe annular region, and
`ventricular flares extending from one portion of the opposite
`side of the annular region.
`
`25
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`BRIEF DESCRIPTION OF THE DRAWINGS
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`35
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`4
`embodiment of a stented valve 10 in accordance with the
`invention is illustrated. Although the stented valves of the
`invention, such as stented valve 10, are primarily described
`herein as being used for mitral valve replacement, it is under—
`stood that many of the features of these stented valves can be
`used for valves in other areas of the heart. For example, the
`stented valves of the invention may be used for replacement
`of the tricuspid valve, where the configuration of such a
`stented valve may be identical or slightly different than
`described herein for replacement ofthe mitral valve due to the
`different anatomy in that area of the heart. In any case, the
`stents and valves of the invention desirably restore normal
`functioning of a cardiac valve, and are intended for percuta-
`neous implantation to take advantage of the benefits of this
`type of surgery. However, the stems described herein may
`instead be implanted using surgical techniques that include
`minimally invasive methods or more traditional open~heart
`surgical methods.
`Stented valves of the invention, such as stented valve 10,
`comprise a stent or stent frame and a valve comprising at least
`one leaflet that is attached within the interior portion of the
`stent frame using a variety of different stent attachment
`devices and methods. Exemplary embodiments of the stent
`frames of the invention are shown and described relative to
`the figures, such as exemplary stent frame 12. The stent
`frames used for the stented valves described herein may be
`fabricated of platinum, stainless steel, Nitinol, superelastic
`polymers (which in turn could be a shape memory polymer),
`or other biocornpatible metals or combinations ofmetals. The
`stent frames may alternatively be fabricated using wire stock,
`or may be produced by machining or laser cutting the stent
`from a metal tube, as is commonly employed in the manufac-
`turing ofstents. The number of wires, the positioning of such
`Wires, and various other features ofthe stent can vary consid-
`erably from that shown in the figures, while remaining within
`the scope of the invention.
`In any case, the stent frames ofthe invention are preferably
`compressible to a relatively small diameter for insertion into
`a patient, but are also at least slightly expandable from this
`compressed condition to a larger diameter when in a desired
`position in the patient. It is further preferable that the process
`ofcompressing the stent frames does not permanently deform
`them in such a way that future expansion thereof would be
`difficult or impossible. That is, each stent should be capable of
`maintaining a desired structural integrity after being com—
`pressed and expanded. In one preferred embodiment of the
`invention, the wires that make up each ofthe stent frames can
`be formed from a shape memory material, such as a nickel
`titanium alloy (e.g., Nitinol). With mis material, the stent
`frame can be self-expandable from a contracted state to an
`expanded state, such as by the application of heat, energy, or
`the like, or by the removal of external forces (e.g., compres-
`sive forces). Alternatively, the stent frame can be made of
`materials that are expandable via expansion of a balloon or
`other device that causes the stent frame to move from a
`compressed condition to an expanded condition. The stent
`frame should be repeatedly compressible and expandable
`without damaging the structure ofthe stent frame. In addition,
`the stent frame may be laser cut from a single piece of mate-
`rial, as mentioned above, or may be assembled from a number
`of different components or wires. For these types of stent
`NORRED EXHIBIT 2229 - Page 7
`structures, one example of a delivery system that can be used
`includes a catheter with a retractable sheath that covers the
`is to be
`stent and its associated valve structure until
`it
`deployed, at which point the sheath can be retracted to allow
`the stent frame to expand. Further details of such a delivery
`
`The present invention will be further explained with refer-
`ence to the appended Figures, wherein like structure is 30
`referred to by like numerals throughout the several views, and
`wherein:
`'
`FIGS. 1 and 2 are top schematic views of a bi-leaflet and a
`tri-leaflet tissue valve of the invention, respectively, and
`including multiple chord placement locations;
`FIG. 3 is an oblique view of the tissue valve of FIG. 1 and
`illustrating multiple anterior chords;
`FIG. 4 is an oblique View of the tissue valve of FIG. 1 and
`illustrating multiple posterior chords;
`FIG. 5 is a schematic partial cross-sectional View of a tissue 40
`valve of the type illustrated in FIGS. 3 and 4 as positioned
`within a stent frame; _
`FIG. 6 is a front schematic view of an exemplary stent of
`the type that can be used with the tissue valves of the inven-
`tion;
`FIG. 7 is an oblique View ofa portion ofa tissue valve with
`attached chords;
`FIG. 8 is a cross-sectional side View ofa portion ofa tissue
`valve and illustrating exemplary chord attachment configu-
`rations;
`FIG. 9 is a top schematic view of another valve arrange-
`ment of the invention;
`FIG. 10 is a schematic sectional view ofa portion ofa heart
`with a stent frame of the invention positioned within the
`annulus of a mitral valve;
`FIG. 11 is a top schematic View ofone exemplary leaflet of
`another valve arrangement of the invention;
`FIG. 12 is a top view of another valve arrangement of the
`invention, with the leaflets in their closed position; and
`FIG. 13 is a top view ofthe valve arrangement of FIG. 12, 60
`with the leaflets in their open position.
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`DETAILED DESCRIPTION
`
`Referring now to the Figures, wherein the components are 65
`labeled with like numerals throughout the several Figures,
`and initially to FIGS. 1—5, a variety ofviews ofone exemplary
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`US 8,323,336 B2
`
`5
`process for delivering stented valves of the present invention
`are discussed in further detail below.
`The stented valves described herein comprise one or more
`valve materials attached within the inner area of the stent
`frame to form leaflets. These stented valve assemblies of the
`invention may use pericardial valve material provided in a
`tricuspid or bicuspid leaflet configuration. These configura-
`tions provide additional valve strength in the relatively high-
`pressure conditions that exist in the mitral valve area of the
`heart, and can also allow greater flexibility in designing a
`valve with a particular size and/or shape.
`Referring again to FIGS. 1-5, a stented pericardial valve 10
`is provided, which is designed to mimic the native anatomy of
`the atrioventricular cardiac valves. This valve 10 is different
`from other ventriculo-arterial valves (i.e., semi-lunar valves)
`in that it depends on tendinous chords 30 (chordae tendinae)
`to anchor the leaflets to a stent frame and prevent the prolapse
`ofleaflets into the atrium. In this Way, the stented valve 10 can
`advantageously have a relatively short annular height. This
`can be particularly beneficial for transcatheter valves, as this
`relatively short annulus height provides a stent that is able to
`be crimped to a relatively small size, and more closely repli-
`cates the function of the native mitral valve. In addition, the
`small annular height is advantageous for positioning of the
`valve, as it will fit more tightly around the native valve annu-
`lus, thereby forming a better seal. This concept can be used
`for either bi-leaflet valves, as is illustrated in FIGS. 1 and 3—5,
`or for tri-leaflet valves, as is illustrated in FIG. 4. In either
`case, the valve structures include multiple chords 30 attached
`to or through the surface of the valve leaflets. The artificial
`chords can be made of ePTFE, for example, and are attached
`to the surface ofthe leaflets to prevent prolapse ofthe leaflets
`into the atrium.
`As is best illustrated in FIG. 5, stented valve 10 generally
`includes a stent or stent frame 12 and a valve 14 attached
`within the interior portion ofthe stent 12. The stent frame 12
`generally includes an annular portion 16, an atrial portion 18
`extending from one end of the annular portion 16, and a
`ventricular portion 20 extending from the opposite end of the
`annular portion 16. Atrial portion 18 includes a wire structure
`that is shaped to flare or extend radially outward at an angle
`around the periphery ofone end ofthe annular portion 16. The
`atrial portion 18 is provided for engagement with one side of
`the annulus in which the stent frame 12 will be implanted,
`thus, the atrial portion 18 can be designed with a number of
`different configurations to meet the different requirements of
`the locations in which it may be implanted. Ventricular por-
`tion 20 also includes a structure that flares or extends radially
`outward at an angle relative to the annular portion 16. A
`section ofthis ventricular portion 20 can be specifically flared
`relative to the annular portion 16 in order to engage with the
`aortic leaflet (i.e., the aortic portion of the ventricular flare)
`but still not substantially block the left ventricular outflow
`tract. The ventricular portion 20 is provided for particular
`engagement with an annulus in which the stent frame will be
`implanted, such as the posterior side of a mitral annulus;
`however, it should not obstruct the left ventricular outflow
`tract when implanted in the mitral position.
`The stent frame 12 may include a number of wires or wire
`portions that are attached to each other generally as shown in
`the illustrated configuration, where one arrangement could
`include separate wires for each of the annular portion 16, the
`atrial portion 18, and the ventricularportion 20. Alternatively,
`the entire stent frame 12 may be cut from a single sheet of
`material such that the stent frame 12 is an integral structure
`that does not include individual components. The relative
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`trated for each of the portions of the stent frame 12 are
`exemplary, and the consfiuction can instead include different
`sizes, numbers, and configurations of these components.
`When the stented valve is being provided for replacement
`of the mitral valve, it is typically provided in an elliptical or
`oval shape, as is illustrated in FIGS. 1-4. In particular, FIGS.
`1, 3, and 4 illustrate an exemplary bi-leaflet valve 14 which
`comprises an anterior leaflet 22 and a posterior leaflet 24. The
`leaflets 22, 24 can be constructed of pericardium material
`with a relatively thin profile at the annulus. In the atrial view
`ofa bi-leaflet valve ofFIG. 1 and the atrial view ofa tri-leaflet
`valve of FIG. 2, multiple chord placements are illustrated as
`“X” markings on the leaflets, where the number ofchords can
`be smaller or larger than illustrated. The chords can alterna-
`tively or additionally be attached to the edge of the leaflet as
`well as the body. FIG. 3 illustrates chords 30 extending from
`the anterior leaflet 22 and FIG. 4 illustrates chords 30 extend-
`ing from the posterior leaflet 24. FIG. 5 illustrates chords 30
`of such a bi-leallet valve 14 attached to stent frame 12, with
`the chords 3 I) attached to both the leaflets ofthe valve and the
`ventricular portion 20 ofthe stent frame 12. In this illustrated
`embodiment, the ends ofthe chords are attached at a point of
`the ventricular portion furthest from the annular portion,
`however,
`it is understood that the chords can instead be
`attached at dilferent locations on the stent flame. The chords
`may also be attached at one or more levels of the ventricular
`flares.
`'
`Attachment of the multiple chords 30 to the surface of the
`leaflets can be performed in a number of different types of
`ways, where a particular stented valve can use one or more
`different types of attachment methods and/or devices. One
`attachment method is generally illustrated in FIGS. 3 and 4, in
`which each chord 30 is passed through the leaflet material in
`two locations that are at closely adjacent to one another so that
`both ends of the chord are on the same side of the leaflet and
`arranged as a pair. When attaching the ends ofthese chords to
`a stent flame, each end of the pair can be attached indepen-
`dently to the stent frame at locations that are spaced at least
`somewhat from each other, or the pair of chord ends can be
`treated as a single unit and kept together as a pair when being
`attached to the stent frame.
`Another attachment method is illustrated in FIG. 7, which
`shows a chord 32 entering a leaflet material at a location 34,
`extending across the opposite side ofthe leaflet by a distance
`(shown as a broken line), and then exiting the leaflet material
`at a location 36. Such a separation ofthe ends of the chord in
`this way can distribute the forces and help to prevent possible
`tearing or ripping of the leaflet material.
`Additional attachment methods are illustrated for attaching
`chords to a leaflet portion 40 in FIG. 8. Leaflet portion 40
`includes a first surface 50 and an opposite surface 52. Chord
`42 is shown as having one end attached to a piece of material
`or tab 44 that is positioned against Lhe second surface 52 ofthe
`leaflet portion 40. The chord 42 then passes through the leaflet
`40, extends across a portion ofthe first surface 50, then passes
`back through the leaflet so that its free end extends from the
`second surface 52. Similarly, chord 46 has one end attached to
`a piece ofmaterial or tab 48 that is positioned against the first
`surface 50 of the leaflet portion 40. The chord 46 passes
`through the leaflet 40 so that its free end extends from the
`second surface 52. A single leaflet may comprise one or both
`of these chord attachment configurations, or may comprise
`NORRED EXHIBIT 2229 - Page 8
`one or a combination of different chord attachment configu-
`rations.
`In other alternative arrangements, chords ean be attached
`to leaflets of a valve using sutures, adhesives (e.g., bioadhe-
`
`

`

`US 8,323,336 B2
`
`7
`vided as single structures or may be provided in pairs or larger
`groupings. The chords may also be provided with different
`lengths to accommodate certain desired distances between
`the portion of the leaflet to which they are attached when the
`valve is in its closed configuration and the stent frame to
`which the chords are attached. The chords may further be
`provided with the ability to be adjusted in length, ifdesired, in
`order to optimize the performance of the valve, for example.
`The chords themselves may be made of a wide variety of
`materials, which can generally fall into the broad categories
`of: (l) synthetic or manufactured chords; and (2) harvested or
`native chords. In either case, the chords should be selected to
`have certain properties that are desirable and/or necessary for
`the particular valve in which they will be used. For one
`example, the chord material can be selected to provide chords
`that are not subject to fatigue failure, even after very high
`numbers ofcycles under which the chords will be subjected to
`relatively high stresses. In addition, the chord material can be
`selected from materials that will not stretch, as the perfor-
`mance of the stented valve will significantly suffer if the
`chords can stretch or extend far enough that the leaflets will be
`able to prolapse into the atrium, for example. Examples of
`materials fiom which the chords can be made include silk and
`ultra high molecular weight polyethylene
`The chord material can further be selected to be compatible
`with the material from which the leaflets are made. As
`described above, the leaflets may be made of pericardial
`material; however,
`the leaflets may instead be made of
`another material, such as native leaflets obtained from a donor
`source (cg, leaflets from a porcine valve), leaflets made from
`other membranous tissue in the body, such as intestinal sub-
`mucosa, thin film Nitinol, cloth, or a polymeric material, for
`example. One polymeric material from which the leaflets can
`be made is an ultra high molecular weight polyethylene mate-
`rial commercially available under the trade designation
`“Dyneema” from Royal DSM of the Netherlands. With cer-
`tain leaflet materials,tit may be desirable to coat one or both
`sides of the leaflet with a material that will prevent or mini-
`mize overgrowth. It is :fiirther desirable that the leaflet mate-
`rial is durable and not subject to stretching, deforming, or
`fatigue.
`,
`The stented valves of the invention may alternatively be
`provided with a valve having three or more leaflets, where an
`exemplary tri-leaflet valve 15 is illustrated in FIG. 2. All ofthe
`features and variations described above relative to bi-leaflet
`valves are also applicable for use with tri—leaflet valves or
`with valves having more than three leaflets. For example, the
`valve 15 has three leaflets 26 that are attached along one edge
`to a stent frame that can he oval or elliptical in shape, for
`example. Each of the leaflets 26 includes multiple chords
`extending from their surfaces, where each of the chord place—
`ments is illustrated as an “X” marking on the leaflets. Any of
`the described chord attachment methods described above can
`also be used for attachment of these chords to the leaflets 26
`of the tri-leaflet valve 15.
`FIG. 9 is a top schematic View of a stented valve 80 that
`includes a single piece of leaflet material 82. The leaflet piece
`82 is stitched to a stent frame along an edge 84, thereby
`creating a fixed leaflet portion 92 and a moveahle leaflet
`portion 94. Leaflet portion 94 can move relative to fixed
`portion 92 along fold line 86, where its free edge closes
`against a stent edge 88. In order to keep the leaflet portion 94
`from prolapsing or moving too far into a vessel, leaflet portion
`94 can have multiple chords attached to it using any of the
`materials and techniques described above, such as at the
`locations 90 designated by an “X” in the figure.
`
`10
`
`15
`
`25
`
`30
`
`35
`
`40
`
`45
`
`50
`
`60
`
`65
`
`8
`FIG. 11 illustrates a leaflet piece 100 that includes another
`chord attachment arrangement for use with a stent frame. In
`particular, leaflet piece 100 includes a base portion 102 and
`multiple chord or attachment portions 104 that are fomied by
`cutting leaflet piece 100 along cut lines 106. In use, the base
`portion 102 is attached to a stent frame along an attachment
`edge 110 and the chord portions 104 can be folded downward
`generally along a fold line 108. The free ends 112 ofthe chord
`portions 104 are attachable to a lower portion ofa stent frame
`(e.g., a ventricular portion of a frame) to function to prevent
`leaflet prolapse, in accordance with the invention.
`FIGS. 12 and 13 illustrate another valve embodiment 120
`that comprises an anterior leaflet 122 and a posterior leaflet
`124 that are attached to a stent frame. In this embodiment,
`posterior leaflet 124 has two gaps or openings along one edge
`that allow for a more flexible movement of the leaflet 124
`during opening and closing of the valve. FIG. 12 shows the
`leaflets in a closed position and FIG. 13 shows the leaflets in
`an open position. These Figures illustrate the changes that
`take place in the stent shape and size during a cardiac cycle. In
`particular, during filling, the stent will be at its largest shape
`and the gaps will be open, as is illustrated in FIG. 13 with open
`gaps 128, an open area 132, and a broken line 130 that gen-
`erally shows the intersection line of the leaflets when the
`valve is in its closed position. During systole and ventricular
`ejection, the stent or supporting st