1111111111111111 IIIIII IIIII 1111111111 11111 lllll lllll lllll lllll lllll 111111111111111 11111111
`US 20210145572Al
`c19) United States
`
`c12) Patent Application Publication
`US 2021/0145572 Al
`c10) Pub. No.:
`
`(43) Pub. Date: May 20, 2021
`Dasi et al.
`
`(54)TRI-LEAFLET
`
`
`PROSTHETIC HEART VALVE
`
`
`
`
`
`Related U.S. Application Data
`
`
`
`
`
`(71) Applicants:Lakshmi Prasad DASI, Dublin, OH
`
`30, 2017.
`
`(US); Atieh Yousefi KOUPAEI,
`
`
`Columbus, OH (US); Megan Kristine
`
`
`HEITKEMPER, Columbus, OH (US);
`(51)
`Int. Cl.
`
`
`Ohio State Innovation Foundation,
`A61F 2124 (2006.01)
`
`Columbus, OH (US)
`(52)U.S. Cl.
`CPC ...... A61F 212418 (2013.01); A61F 2240/001
`
`
`
`
`(2013.01); A61F 2250/0037 (2013.01)
`
`(60) Provisional application No. 62/527,632, filed on Jun.
`
`
`
`Publication Classification
`
`(72) Inventors: Lakshmi Prasad Dasi, Dublin, OH
`
`
`
`(US); Atieh Yousefi Koupaei,
`
`
`Columbus, OH (US); Megan Kristine
`
`
`Heitkemper, Columbus, OH (US)
`(57)
`
`ABSTRACT
`
`(21)Appl. No.:16/625,442
`
`(22)PCT Filed:Jun. 29, 2018
`
`A prosthetic heart valve includes a first upper frame portion
`
`
`(73)Assignee: Ohio State Innovation Foundation,
`
`
`
`
`and a stent frame connected to the first upper frame portion
`
`Columbus, OH (US)
`
`
`
`via at least two stent frame extensions. The stent frame
`
`includes a base and at least two stent posts extending
`
`
`upwardly from the base towards the first upper frame
`
`
`portion. The first upper frame portion, the base, and the at
`
`least two stent posts each has an inner surface and an outer
`
`
`
`
`surface. The prosthetic heart valve also includes at least one
`(86) PCT No.:PCT/US2018/040415
`
`
`
`
`sheet of leaflet material configured to encircle the stent
`
`
`frame and weave through the stent frame between the first
`
`upper frame portion and the base.
`
`§ 371 (c)(l),
`(2) Date:Dec. 20, 2019
`
`136
`
`132
`
`164(a)
`
`130(a)
`
`164(c)
`
`122
`
`114
`
`�
`
`, .....---·· ·
`
`•.•..
`
`120
`
`Medtronic Exhibit 1043
`Medtronic Corevalve v. Colibri Heart Valve
`IPR2020-01454
`Page 00001
`
`

`

`Patent Application Publication May 20, 2021 Sheet 1 of 26
`
`US 2021/0145572 Al
`
`18
`
`18
`
`18
`
`FIG.1
`
`24
`
`22
`
`10
`
`32 ~ 46
`
`44
`
`12
`
`FIG. 2
`
`IPR2020-01454 Page 00002
`
`

`

`Patent Application Publication May 20, 2021 Sheet 2 of 26
`
`US 2021/0145572 Al
`
`30c
`
`30b
`
`30a
`
`14
`
`20
`
`26
`
`FIG. 3
`
`IPR2020-01454 Page 00003
`
`

`

`Patent Application Publication May 20, 2021 Sheet 3 of 26
`
`US 2021/0145572 Al
`
`I.()
`
`l9
`LI..
`
`IPR2020-01454 Page 00004
`
`

`

`Patent Application Publication May 20, 2021 Sheet 4 of 26
`
`US 2021/0145572 Al
`
`\
`
`42
`
`30
`
`46
`I
`
`38
`
`FIG. 6
`
`40
`
`FIG. 7
`
`38
`
`IPR2020-01454 Page 00005
`
`

`

`Patent Application Publication May 20, 2021 Sheet 5 of 26
`
`US 2021/0145572 Al
`
`14
`
`~ ~
`3:~
`
`56
`
`58
`
`FIG. 8
`
`IPR2020-01454 Page 00006
`
`

`

`Patent Application Publication May 20, 2021 Sheet 6 of 26
`
`US 2021/0145572 Al
`
`36
`
`FIG. 9
`
`48
`
`FIG.10
`
`IPR2020-01454 Page 00007
`
`

`

`Patent Application Publication May 20, 2021 Sheet 7 of 26
`
`US 2021/0145572 Al
`
`14
`
`FIG. 11
`
`20
`
`20
`
`FIG. 12
`
`IPR2020-01454 Page 00008
`
`

`

`Patent Application Publication May 20, 2021 Sheet 8 of 26
`
`US 2021/0145572 Al
`
`136
`
`132
`
`164(c)
`
`122
`
`114
`~
`
`\
`\
`
`13~(c)
`\ \
`\
`
`164(a)
`
`130(a)
`
`120
`
`FIG.13
`
`IPR2020-01454 Page 00009
`
`

`

`Patent Application Publication May 20, 2021 Sheet 9 of 26
`
`US 2021/0145572 Al
`
`114 ~
`
`120
`
`FIG.14
`
`IPR2020-01454 Page 00010
`
`

`

`Patent Application Publication May 20, 2021 Sheet 10 of 26 US 2021/0145572 Al
`
`119
`
`160
`
`118
`
`FIG.15
`
`IPR2020-01454 Page 00011
`
`

`

`Patent Application Publication May 20, 2021 Sheet 11 of 26
`
`US 2021/0145572 Al
`
`132
`
`137
`
`i
`i;
`//
`/ ,
`
`FIG.16
`
`IPR2020-01454 Page 00012
`
`

`

`Patent Application Publication May 20, 2021 Sheet 12 of 26 US 2021/0145572 Al
`
`l?
`LL.
`
`IPR2020-01454 Page 00013
`
`

`

`Patent Application Publication May 20, 2021 Sheet 13 of 26 US 2021/0145572 Al
`
`70
`
`~ 0
`
`0
`
`114
`
`FIG.18
`
`IPR2020-01454 Page 00014
`
`

`

`Patent Application Publication May 20, 2021 Sheet 14 of 26 US 2021/0145572 Al
`
`FIG.19
`
`/114
`
`FIG. 20
`
`IPR2020-01454 Page 00015
`
`

`

`Patent Application Publication May 20, 2021 Sheet 15 of 26 US 2021/0145572 Al
`
`272
`
`FIG. 21
`
`IPR2020-01454 Page 00016
`
`

`

`Patent Application Publication May 20, 2021 Sheet 16 of 26 US 2021/0145572 Al
`
`260
`
`/214
`
`FIG. 23
`
`214
`
`f
`
`FIG. 24
`
`IPR2020-01454 Page 00017
`
`

`

`Patent Application Publication May 20, 2021 Sheet 17 of 26 US 2021/0145572 Al
`
`-,--__ 322
`
`/314
`
`FIG. 25 320
`
`FIG. 26
`
`IPR2020-01454 Page 00018
`
`

`

`Patent Application Publication May 20, 2021 Sheet 18 of 26 US 2021/0145572 Al
`
`52
`
`h
`\
`
`D
`
`H
`
`54
`
`so
`
`FIG. 28
`
`FIG. 27
`
`IPR2020-01454 Page 00019
`
`

`

`Patent Application Publication
`
`May 20, 2021 Sheet 19 of 26
`
`US 2021/0145572 Al
`
`300
`
`0
`
`-100
`
`- - - - - - - · Fenlrh:lllar Pressm·e
`Aortic Pre.,;;sure
`Flow Rate
`
`30
`
`'• ,,
`', ',
`\
`'•
`
`0
`
`-10
`
`0
`
`0.2
`
`0.4
`Time (s)
`
`0.6
`
`0.8
`
`FIG. 29
`
`IPR2020-01454 Page 00020
`
`

`

`Patent Application Publication May 20, 2021 Sheet 20 of 26
`
`US 2021/0145572 Al
`
`X0 0XY0»>'l.P/'i4
`0-.-,»w-.-w«»w LI'S,4
`---LPL.A
`, .... , ., ... '"' , J\f PNA
`-................. JlfPSA
`««»«•«Y<->« llPJ\(4
`
`.. f)<'; I!-.. ___ . . . . . . . ___ . . . . . . . ___ . . . . . . . ___ _ ._ ___ - '
`',_, 0
`0.4
`0.6
`0.8
`(),2
`Ttmt• {S}
`
`FIG. 30
`
`IPR2020-01454 Page 00021
`
`

`

`Patent Application Publication May 20, 2021 Sheet 21 of 26
`
`US 2021/0145572 Al
`
`{a}
`
`I
`
`(]~:;::~:\:~\~: l"::-~::~f~:~:~
`R>:,f:'l{j;:),,ff1{:•fa:::{:t\i:;:;:;
`
`I
`
`(J,:,:::,:::wfr;;i,t,:.1:1::
`{~.:z::g)jt~~~~1t:\sn r$.1~~t:~~n:
`
`Low Profile Medium Profile High Profile
`
`No Arch
`
`Short Arch
`
`Long Arch
`
`FIG. 31
`
`FIG. 32
`
`IPR2020-01454 Page 00022
`
`

`

`Patent Application Publication May 20, 2021 Sheet 22 of 26 US 2021/0145572 Al
`
`LPNA
`
`MPNA
`
`HPNA
`
`{g)
`
`/L m
`
`FIG. 33
`
`IPR2020-01454 Page 00023
`
`

`

`Patent Application Publication May 20, 2021 Sheet 23 of 26 US 2021/0145572 Al
`
`LPSA
`
`LPLA
`
`MPSA
`
`FIG. 34
`
`IPR2020-01454 Page 00024
`
`

`

`Patent Application Publication May 20, 2021 Sheet 24 of 26 US 2021/0145572 Al
`
`iWlillltlllillltlliili!il4lff i'HliM
`RSS
`{(u'v'}/U~)) o O.ll02 0.004 o.006 11.0118 0.111 0.1112 0.014 o.016 0.018 o.oi
`
`120 160 200
`
`fl_
`
`A_ fl_
`
`_____________ Early_Systole ______ _J _____________ t~!15.!!Y~!.<>!~----------
`
`l{h)
`
`I l
`
`(g)
`
`{i)
`
`(k)
`
`tlt!ltlltltlltt!ltlltltt L......
`--40 o
`so
`
`rn,. {s '}: --200 --16(> ... 120 --80
`
`Flow d_:'.;ctlon A_
`
`40
`
`Earh' Systole
`
`!
`;(a) ····.••::::,-··········: .... :.
`LPNA I
`
`l
`
`__ Peak Systole ________ _
`
`- . .+ - - (cid:173)
`
`:(e) ·:·:•:.,.,:.
`
`HPNA I
`
`l
`
`(f)
`
`FIG. 35
`
`IPR2020-01454 Page 00025
`
`

`

`Patent Application Publication May 20, 2021 Sheet 25 of 26 US 2021/0145572 Al
`
`B111mmmmmmmmmmmmmrnmmmmmn1
`
`''\ {s''):
`
`·-20<'! ··lGO ··lZO ··8(>
`
`··40
`
`0
`
`4(>
`
`80 120 160 2(>)
`
`Rss
`((u'v')/Uii)) o
`
`-· /L IL
`~--td(~. .
`·-.:.:T,:~-
`
`.r·····:r····--:::::::::rn:rr······: •.......• :.:.:.:;y
`
`0.0112 o.004 0.006 o.oos 0.111 11.012 o.0.14 o.0.16 0.018 0.02
`
`/L IL
`
`Flow direction
`
`,
`Earh· Svstole
`l(a) "'I'·
`. .
`
`LPSA
`
`:
`
`Peak Svstole
`
`i(b} "".'• _:,,_
`
`------------------+----------------------------------------+---------------------------------------
`j (e) ... ,.,,w···
`j!f)
`MPSA !
`j
`!
`l
`
`(kl
`
`FIG. 36
`
`IPR2020-01454 Page 00026
`
`

`

`Patent Application Publication May 20, 2021 Sheet 26 of 26 US 2021/0145572 Al
`
`Re-attachment
`_ .... ,..,.#~·-- ...................................... ~ .. ..
`
`- . · .• •.--.·.•.~· .. ·...
`
`,-------------,:. _____ ,
`
`. ..... ">>·-.. _ .. - - - - -
`{, .•. }. .. -----~······ -
`
`Re-attachment
`
`FIG. 37
`
`FIG. 38
`
`IPR2020-01454 Page 00027
`
`

`

`US 2021/0145572 Al
`
`May 20, 2021
`
`1
`
`TRI-LEAFLET PROSTHETIC HEART VALVE
`
`CROSS REFERENCE OF RELATED
`APPLICATION
`
`[0001] This application claims the benefit of the U.S.
`Provisional Patent Application No. 62/527,632 filed Jun. 30,
`2017, which is incorporated herein by reference in its
`entirety.
`
`FIELD OF THE INVENTION
`
`[0002] The present invention relates to the manufacture
`and use of a prosthetic valve for use in the human heart.
`More specifically, the invention relates to the manufacture
`and use of a valve that may be surgically implanted into the
`heart of a patient in order to replace a native tri-leaflet heart
`valve.
`
`BACKGROUND
`
`[0003] Heart valve replacement is the second most com(cid:173)
`mon cardiac operation performed in the United States.
`Currently, over four million people are diagnosed with heart
`valve disorder across the world, each year. Moreover, heart
`disease is prevalent in about 2.5% of the overall United
`States population, and 10.4% of its elderly population.
`[0004] Typically, prosthetic heart valves used in aortic and
`mitral heart valve replacement procedures are either
`mechanical or bioprosthetic. However, these valves intro(cid:173)
`duce significant risk of thromboembolism, requiring the
`patient to undergo lifelong anticoagulation therapy, or the
`patient become more prone to valve degeneration and tissue
`failure, requiring reoperation. It would be useful to produce
`a prosthetic heart valve that would be durable, while not
`necessitating anticoagulation therapy.
`
`SUMMARY
`
`[0005] A prosthetic heart valve includes a first upper frame
`portion and a stent frame connected to the first upper frame
`portion via at least two stent frame extensions. The stent
`frame includes a base and at least two stent posts extending
`upwardly from the base towards the first upper frame
`portion. The first upper frame portion, the base, and the at
`least two stent posts each has an inner surface and an outer
`surface. The prosthetic heart valve also includes at least one
`sheet of leaflet material configured to weave through the
`stent frame between the first upper frame portion and the
`base.
`[0006] A prosthetic heart valve includes a stent frame with
`a first upper frame portion, a base, and at least two stent
`posts extending upwardly from the base; wherein the base is
`connected to the first upper frame portion by the at least two
`stent posts, and wherein the first upper frame portion, the
`base, and the at least two stent posts each has an inner
`surface and an outer surface; and at least one sheet of leaflet
`material configured to weave through the stent frame from
`the outer surface to the inner surface between the first upper
`frame portion and the base of the stent frame.
`[0007]
`In another embodiment, the at least one sheet of
`leaflet material is disposed on the outer surface of the base
`and of the at least two stent posts, and at least a portion of
`the at least one sheet of leaflet material is tucked under the
`first upper frame portion between the first upper frame
`portion and the base and is disposed on the inner surface of
`the upper frame portion.
`
`[0008]
`In another embodiment, the at least one sheet of
`leaflet material is disposed on the inner surface of the base
`and of the at least two stent posts, and at least a portion of
`the at least one sheet ofleaflet material is tucked in under the
`first upper frame portion between the first upper frame
`portion and the base.
`[0009]
`In another embodiment, the first upper frame por(cid:173)
`tion has a shape that is substantially similar to an upper edge
`of the base.
`[0010]
`In another embodiment, the stent frame further
`comprises a second upper frame portion connected to the
`first upper frame portion, and wherein the second upper
`frame portion has a shape that is substantially similar to an
`upper edge of the first upper frame portion. The stent frame
`may also include a third upper frame portion connected to
`the second upper frame portion, wherein the third upper
`frame portion has a shape that is substantially similar to an
`upper edge of the second upper frame portion. Moreover, the
`at least one sheet ofleaflet material weaves through the stent
`frame between the first upper frame portion and the second
`upper frame portion and/or between the second upper frame
`portion and the third upper frame portion.
`[0011] The base may further have a lower edge that is
`substantially similar to a lower edge of the first upper frame
`portion. And, the at least two stent posts have at least two
`heights different from one another.
`[0012]
`In one embodiment, the at least one sheet of leaflet
`material is a continuous sheet of leaflet material. In another
`embodiment, the continuous sheet of leaflet material com(cid:173)
`prises an upper portion having at least two arches extending
`upwardly therefrom. In another embodiment, the continuous
`sheet of leaflet material comprises one or more spacings in
`the upper portion, wherein each of the one or more spacings
`is disposed between two of the at least two arches. More(cid:173)
`over, the at least one sheet of leaflet material comprises a
`polymer material that may be linear low density polyethyl(cid:173)
`ene, polytetrafluoroethylene,
`low-density polyethylene,
`polyethylene terephthalate, polypropylene, polyurethane,
`polycaprolactone, polydimethylsiloxane, polymethylmeth(cid:173)
`acrylate, polyoxymethylene, thermoplastic polyurethane,
`and combinations thereof. The leaflet material may also
`include hyaluronic acid. And, the at least one sheet of leaflet
`material may include a bioprosthetic material
`[0013]
`In one embodiment, the stent frame has a height
`and an inner diameter, and wherein the ratio of height to
`diameter is from about 0.5 to about 0.9. The at least two
`arches may have a height, and wherein the ratio of the height
`of the at least two arches to the inner diameter of the stent
`frame is from about 0.05 to about 0.12.
`[0014] Finally, the at least one sheet ofleaflet material has
`a three dimensional curvature and wherein the leaflet mate(cid:173)
`rial is two dimensional when heated to form a rounded
`leaflet.
`
`DESCRIPTION OF THE DRAWINGS
`
`[0015] FIG. 1 is a front view of one embodiment of a
`prosthetic heart valve in an open position;
`[0016] FIG. 2 is a perspective view of the prosthetic heart
`valve of FIG. 1;
`[0017] FIG. 3 is a front view of one embodiment of a stent
`frame for use in a prosthetic heart valve;
`[0018] FIG. 4 is a plan view of a rectangular pieces of
`leaflet material before it is attached to the stent frame;
`
`IPR2020-01454 Page 00028
`
`

`

`US 2021/0145572 Al
`
`May 20, 2021
`
`2
`
`[0019] FIG. 5 is a plan view of a piece of leaflet material
`including an arched upper edge;
`[0020] FIG. 6 is a front view of one embodiment of a clip
`for use in a prosthetic heart valve;
`[0021] FIG. 7 is an enlarged rear perspective view of one
`embodiment of the top portion of a clip for use in a
`prosthetic heart valve;
`[0022] FIG. 8 is a front view of another embodiment of a
`stent clip and stent frame for use in a prosthetic heart valve;
`[0023] FIG. 9 is a front view of another embodiment of a
`prosthetic heart valve;
`[0024] FIG. 10 is a perspective valve of the prosthetic
`heart valve of FIG. 8;
`[0025] FIG. 11 is a front view of another embodiment of
`a stent frame for use in a prosthetic heart valve;
`[0026] FIG. 12 is a perspective view of the stent frame of
`FIG. 11;
`[0027] FIG. 13 is a front view of an alternative embodi(cid:173)
`ment of a stent frame for use in a prosthetic heart valve;
`[0028] FIG. 14 is a plan view of the stent frame of FIG. 13;
`[0029] FIG. 15 is top view of the prosthetic heart valve of
`FIG. 13 with the leaflets in a closed position;
`[0030] FIG. 16 is a plan view of a piece ofleaflet material
`before it is attached to the stent frame of FIG. 13;
`[0031] FIG. 17 is an exploded view of an alternative
`embodiment of a stent frame and an outer cover;
`[0032] FIG. 18 is a front view of an alternative embodi(cid:173)
`ment of a stent frame;
`[0033] FIG. 19 is a front view of an alternative embodi(cid:173)
`ment of a stent frame;
`[0034] FIG. 20 is a perspective view of the stent frame of
`FIG. 19;
`[0035] FIG. 21 is a front view of an alternative embodi(cid:173)
`ment of a stent frame;
`[0036] FIG. 22 is a perspective view of the stent frame
`valve of FIG. 21;
`[0037] FIG. 23 is a front view of an alternative embodi(cid:173)
`ment of a stent frame;
`[0038] FIG. 24 is a perspective view of the stent frame of
`FIG. 23;
`[0039] FIG. 25 is a front view of an alternative embodi(cid:173)
`ment of a stent frame;
`[0040] FIG. 26 is a perspective view of the stent frame of
`FIG. 25;
`[0041] FIG. 27 is an exploded perspective view of an
`embodiment of a 3D printed model of a prosthetic heart
`valve;
`[0042] FIG. 28 is a plan view of an embodiment of a 3D
`printed model of a prosthetic heart valve;
`[0043] FIG. 29 is a graphical representation of a pressure
`and flow rates over time for prosthetic heart valve Example
`5 with a medium profile and a short arch;
`[0044] FIG. 30 is a graphical representation of the nor(cid:173)
`malized flow rate over time for prosthetic heart valve
`Examples 1-6;
`[0045] FIGS. 31 and 32 are graphical representations of
`the reverse flow percentages for the closing and regurgita(cid:173)
`tion fractions of Examples 1-6;
`[0046] FIGS. 33 and 34 are high speed camera images of
`Examples 1-6 taken at four time point throughout a typical
`cardiac cycle;
`[0047] FIGS. 35 and 36 are graphical representations of
`averages velocity vectors superimposed by vorticity con-
`
`tours and contours of normalized Reynolds shear stress at
`two time points throughout the cardiac cycles for Examples
`1-6; and
`[0048] FIGS. 37 and 38 are graphical depictions ofhemo(cid:173)
`dynamics for prosthetic heart valves having a no arch and
`varying profiles and varying arch heights, respectively.
`
`DETAILED DESCRIPTION
`
`[0049] A prosthetic heart valve (PHY), including a stent
`frame and leaflet material, having a tri-leaflet design for use
`to replace either a failing or damaged native aortic or mitral
`heart valve in a patient is provided. Although we will refer
`to a tri-leaflet design, it should be apparent to one of skill in
`the art that any number of leaflets may be created using the
`PHY described herein. In one embodiment, the PHY will
`provide a prosthetic valve with a higher effective orifice
`compared to other prosthetic valves that are commercially
`available. The PHY will also provide improved flow char(cid:173)
`acteristics through the geometric design of both the stent
`frame and the leaflet.
`[0050]
`In one embodiment, the design of the stent frame in
`combination with the design of the leaflets enable improved
`performance over other commercially available prosthetic
`valves. For example, the design of the leaflet and/or the
`manner in which the leaflet is disposed on the stent frame
`may improve durability of the PHY, reduce the number of
`sutures required to assemble the PHY, and/or improve leaflet
`coaptation.
`[0051] FIGS. 1 and 2 show illustrate a first embodiment of
`the PHY 10. In the embodiment, the PHY 10 includes a
`suture ring 12, a stent frame 14, a plurality of stent clips 16,
`and a sheet of leaflet material 32 which may be disposed
`between the stent frame 14 and the stent clips 16 in order to
`form at least two leaflets 18.
`In one embodiment the stent frame 14 may be
`[0052]
`formed of a single piece of material, however it should be
`recognized that multiple pieces of stent material may be
`used to create a single stent frame 14. Referring now to FIG.
`3, the stent frame 14 may be laser cut from a cylindrical tube
`or pipe. Alternatively, the stent frame 14 may be laser cut
`from a flat piece of material, rolled into the desired shape,
`and affixed to hold the shape at either of the free ends (not
`shown). In another embodiment, the stent frame may be
`"printed" or molded using additive manufacturing tech(cid:173)
`niques known to those of skill in the art.
`[0053] Generally, the stent frame 14 includes a generally
`circular base 20 defining the valve orifice of the PHY 10 and
`at least two, and in one embodiment three, stent posts 22
`extending upwardly from the base 20. The stent frame 14
`may also include a plurality of suture openings 24 in order
`to facilitate attachment of the stent frame 14 to the leaflet
`material 32 (as shown in FIG. 1).
`[0054] The stent frame 14 may be made of stainless steel,
`nitinol, cobalt chromium or other suitable material. It should
`be understood that the base 20 of the frame 14 may be
`generally circular in nature or it may be elliptical, oval, or
`other shape suitable to the curvature of the patient's valve
`annulus. As shown in FIGS. 11 and 12, the base 20 may
`alternatively have an undulating, rather than straight, shape
`to better fit the anatomical curvature of a patient's vessel. It
`should also be understood that the stent posts 22 that extend
`from the base 20 of the stent frame 14 may be placed
`equidistant around the circumference of the stent frame 14
`or they may be placed at irregular intervals in order to more
`
`IPR2020-01454 Page 00029
`
`

`

`US 2021/0145572 Al
`
`May 20, 2021
`
`3
`
`closely mimic the natural shape of the patient's native valve.
`The stent frame 14 maybe be produced in varying sizes,
`depending on the size of the patient's heart. For example, the
`base 20 of the stent frame 14 may have a diameter of 17, 19,
`21, 23, 25, 27, 29, or 31 millimeters (mm). The base of the
`stent frame 14 may also include an additional plurality of
`suture openings 26 intended to facilitate attachment of the
`frame 14 to the suture ring 12 (as shown in FIGS. 1 and 2).
`[0055] The stent posts 22 generally extend upwards from
`the stent base 20. In one embodiment, the stent posts 22 have
`a curved triangular shape, creating scalloped edges 28,
`extending between top point 30(a) and top point 30(b), top
`point 30(b) and top point 30(c), and top point 30(c) and top
`point 30(a). The stent posts 22, when wrapped with the
`leaflet material 32, define the leaflets 18 ( or cusps) of the
`PHY 10, as shown in FIG. 1.
`[0056] Referring now to FIGS. 1, 4, and 5, the leaflets 18
`of the PHY 10 may be created using a single piece of
`polymeric or bioprosthetic (such as porcine or bovine peri(cid:173)
`cardium) material 32. It will also be understood that the
`leaflets 18 may also be created using separate pieces of
`leaflet material affixed between each set of stent posts 22.
`[0057] As shown in FIG. 4, in one embodiment, a con(cid:173)
`tinuous sheet of leaflet material 32 may include an upper
`edge portion 34 and be generally rectangular in shape, or as
`shown in FIG. 5, may include an upper edge portion 34
`having at least one arch 36 extending upwardly therefrom.
`[0058] The leaflet material 32 may be made of a polymeric
`material, such as linear low density polyethylene (LLDPE),
`polytetrafluoroethylene (PTFE), low-density polyethylene
`(LDPE), polyethylene terephthalate (PET), polypropylene
`(PP), polyurethane, polycaprolactone (PCL), polydimethyl(cid:173)
`siloxane (PDMS), polymethylmethacrylate (PMMA), poly(cid:173)
`oxymethylene (POM), thermoplastic polyurethane (TPU),
`and combinations thereof.
`[0059]
`In one embodiment, the leaflet material 32 may be
`made of a polymeric material, such as LLD PE, that includes
`hyaluronic acid to prevent blood clot and thrombosis for(cid:173)
`mation. An example of this material is disclosed in U.S.
`application Ser. No. 14/381,332, entitled Glycosaminogly(cid:173)
`can and Synthetic Polymer Material for Blood-Contacting
`Applications, which is incorporated herein by reference in
`its entirety.
`[0060] As shown in FIG. 1, the leaflet material 32 may be
`wrapped about and sutured to the outer circumference of the
`stent frame 14 through the plurality of suture openings 24 in
`the stent posts 22, forming three leaflets 18 resembling the
`tri-leaflet aortic heart valve in the normally open position. It
`should be understood that a PHY may also be made having
`two leaflets to mimic the bi-leaflet mitral heart valve.
`[0061] By using a single continuous piece of leaflet mate(cid:173)
`rial mounted around the stent frame 14, the number of
`sutures required to assemble the leaflets 18 is reduced.
`However, it should be appreciated that multiple pieces of
`leaflet material 32 may be mounted about the outer circum(cid:173)
`ference of the stent frame 14.
`In one embodiment, the suture ring 12 may be
`[0062]
`covered in a suitable material, such as Dacron®, disposed
`atop the leaflet material 32, and affixed to the stent frame 14
`with sutures or other means, such as the use of a suitable
`adhesive. By covering only the suture ring 12 with Dacron®
`the outer and inner diameter of the PHY are reduced,
`allowing for a larger valve area and, consequently, a higher
`effective orifice area.
`
`[0063] Referring again to FIG. 1, once the leaflet material
`32 is affixed to the stent frame 14, stent clips 16 are affixed
`to each of the stent posts 22 through the suture openings or
`with adhesive, such that the leaflet material 32 is disposed
`there between. The stent clips 16 may be formed of stainless
`steel, nitinol, or other suitable material.
`[0064] Referring specifically to FIGS. 6 and 7, in one
`embodiment, the stent clips 16 have a facial surface 38 and
`suture openings 40 that may be laser cut to mimic the shape
`of the outer surface of stent posts 22. Referring to FIG. 7, the
`stent clips 16 may also include a top point portion 56 that
`includes a left flange 42, right flange 44, and top flange 46
`that extend from the facial surface 38 of the stent clips 16
`toward the inner surface (not shown) of the stent frame 14.
`[0065]
`In another embodiment, the outer surface of the
`stent clips 16 may be covered with Dacron® or other
`suitable material (not shown) in order to provide smooth
`contact between the stent posts 22 and the vessel wall.
`[0066] As shown in FIGS. 6 and 7, in one embodiment, the
`stent clips 16 may be distinct pieces, formed separately from
`the stent frame 14. In another embodiment, as shown in FIG.
`8, the stent clips 16 may be integrally formed with the stent
`frame 14. In this embodiment, the top point portion 56 of
`each stent clip 16 may be connected to the top point portion
`30 of the respective stent post 22. In this embodiment, the
`stent clips 16 can be folded at the connection point 58, with
`the facial surface 38 of the stent clip 16 facing the outer
`surface of the stent post 22. The stent clip 16 is then affixed
`to the stent posts 22 through the respective suture openings
`or with adhesive, sandwiching the leaflet material 32 there
`between, as described above.
`[0067] As shown in FIG. 2, the stent clip flanges (42, 44,
`46) are designed to gather the leaflet material 32 at the stent
`post 22, enabling the leaflets 18 to mimic the function of a
`native aortic heart valve cusp, opening and closing with the
`flow of blood through the PHY 10. Specifically, the stent
`clips 16 provide improved commissure coaptation adjacent
`to the sent posts and enhance closing dynamics of the
`leaflets.
`[0068] Referring to FIGS. 5, 9, and 10, in another embodi(cid:173)
`ment, the leaflet material 32 may include an upper edge
`portion 34 with a plurality of arches 36. It should be
`understood that the arches 36 may be formed integrally with
`the single sheet of leaflet material 32 or may be attached to
`the upper edge portion 34 after the material is formed. The
`arches 36 on the upper edge portion 34 provide arched
`leaflets 48 (as shown in FIG. 9), when wrapped around the
`stent frame 14. Through the use of arched leaflets 48, it was
`discovered that flow reattachment is facilitated and recircu(cid:173)
`lation regions that are directly related to thrombus formation
`are decreased. In addition, the use of arched leaflets 48
`provide an improved leaflet coaptation.
`[0069]
`In another embodiment, once the sheet of leaflet
`material 32 is installed onto the stent frame 14, the leaflets
`18 may be further formed by applying a combination of heat
`and pressure to the once the planar leaflets 18. This treatment
`can be used to further change the shape of the leaflets 18 into
`a three dimensional configuration (as is the case for native
`valve leaflets). In one embodiment, vacuum pressure is
`applied to the formed PHY 10 on the upstream side of the
`PHY to force the leaflets 18 to close and then heat is applied
`from the downstream side in order to make the polymer
`(which is a thermoplastic) relax and stretch under the forces
`
`IPR2020-01454 Page 00030
`
`

`

`US 2021/0145572 Al
`
`May 20, 2021
`
`4
`
`exerted by the vacuum. The resulting shape of the leaflets 18
`may more closely resemble the patent's native leaflet shape.
`[0070]
`In other set of embodiments, the stent frame 14
`may have various other designs, while the leaflet material 32
`may be secured to the stent frame 14 in generally the same
`or similar manner as set forth above. In one embodiment, as
`shown in FIGS. 11 and 12, the base 20 of the stent frame 14
`may have an undulating, rather than straight, shape to better
`fit the anatomical curvature of a patient's vessel.
`[0071]
`In another embodiment, as shown in FIG. 17, an
`outer cap 166 may be used to secure the leaflet material to
`the stent frame 114. In this embodiment, the outer cap 166
`may be disposed to fit over the outer surface of the stent
`frame 114, sandwiching the leaflet material between the
`frame 114 and the cap 166.
`[0072]
`In another set of embodiments, as shown in FIGS.
`13-16, and 18-24, the PHY 10 may have a stent frame that
`includes an upper frame portion, a base, and at least two
`stent posts ( e.g., two stent posts, three stent posts, etc.).
`Referring to FIG. 13 for example, the stent frame 114
`includes an upper frame portion or a first upper frame
`portion 160, a base 120, and stent posts 122 ( e.g., at least two
`stent posts 122). Generally, the upper frame portion 160 has
`a shape that mimics that of the upper edge 162 of and
`between the stent posts 122. The upper frame portion 160
`connects to the stent posts 122 only at each of the top points
`130(a)-(c) by stent frame extensions 164(a)-(c), respec(cid:173)
`tively.
`[0073]
`In this embodiment, the leaflet material may be
`attached to the stent frame 114 as described above with the
`use of stent clips. However, in an alternative embodiment, as
`shown in FIGS. 13, 14 and 15 the leaflet material may be
`attached to the stent frame 114 by weaving the single piece
`of leaflet material 132 between the stent frame 114 and the
`upper frame portion 160 such that either the bottom portion
`of the leaflet material (as shown in FIGS. 4 and 5) is
`disposed against the inner surface of the stent frame 114 and
`the upper portion of the leaflet material is disposed against
`the outside surface of the upper frame portion 160 or the
`bottom portion of the leaflet material is disposed against the
`outer surface of the stent frame 114 and the upper portion is
`disposed against the inner surface of the upper frame portion
`160. The leaflet material may then be further secured to the
`stent frame 114 using sutures or adhesives, as described
`above.
`[0074] While reducing the number of sutures needed to
`secure the leaflet material to the frame 114, this embodiment
`also protects the formed leaflets (not shown) from possible
`tearing as they expand and contract over the top of the upper
`frame portion 160. Moreover, in embodiments that the
`leaflet material 132 is woven through the stent frame 114 as
`shown in FIGS. 13 and 15, the upper frame portion 160
`gathers the leaflet material 132 and enables the leaflets 118
`to mimic the function of a native aortic heart valve cusp,
`opening and closing with the flow of blood through the PHY
`10. As such, the stent clip may be eliminated. The leaflet
`material 132 may be further adhered to the outside of the
`stent frame 114 by using a minimal amount of sutures.
`[0075]
`In another embodiment of the leaflet material, as
`shown in FIG. 16, the continuous sheet of leaflet material
`132 may include one or more spacings or notches 137 in the
`upper edge portion 134. This embodiment ofleaflet material
`is particularly useful with the stent frames shown and
`described in FIGS. 13-15. For example, each of the one or
`
`more spacing or notches 137 is between every two directly
`adjacent arches 136. The one or more spacings 137 may
`improve coaptation of the leaflets 118 when wrapped around
`stent frame extensions 164. For example, the one or more
`spacing 137 may help accommodating the opening and
`closing motions of the leaflets 118, such that the commis(cid:173)
`sures 119 meet with better conformity to achieve better
`coaptation and ensure minimal reverse flow of the blood
`when the leaflets 118 are closed, as shown in FIG. 15.
`[0076] As shown in FIGS. 18-20, the stent frame 114 may
`include multiple upper frame portio