11111111111111111111111111111119,111!!liljtIll0101111111111111110111111
`
`(19) United States
`(12) Patent Application Publication (10) Pub. No.: US 2003/0014104 Al
`Jan. 16, 2003
`Cribier (cid:9)
`(43) Pub. Date: (cid:9)
`
`(54) VALUE PROSTHESIS FOR IMPLANTATION
`IN BODY CHANNELS
`
`(30) (cid:9)
`
`Foreign Application Priority Data
`
`Dec. 31, 1996 (EP) (cid:9)
`
` 96402929.2
`
`(76) Inventor: Alain Cribier, Maromme (FR)
`
`Publication Classification
`
`Correspondence Address:
`REED SMITH, LLP
`ATTN: PATENT RECORDS DEPARTMENT
`599 LEXINGTON AVENUE, 29TH FLOOR
`NEW YORK, NY 10022-7650 (US)
`
`(21) Appl. No.: (cid:9)
`
`10/139,741
`
`(22) Filed: (cid:9)
`
`May 2, 2002
`
`Related U.S. Application Data
`
`(63) Continuation of application No. 09/795,803, filed on
`Feb. 28, 2001, which is a continuation of application
`No. 09/345,924, filed on Jul. 1, 1999, filed as 371 of
`international application No. PCT/EP97/07337, filed
`on Dec. 31, 1997.
`
`Int. C1.7 (cid:9)
`(51)
`(52) U.S. Cl. (cid:9)
`
`A61F 2/24
` 623/2.11; 623/2.14; 623/2.18
`
`(57) (cid:9)
`
`ABSTRACT
`
`A valve prosthesis which is especially useful in the case of
`aortic stenosis and capable of resisting the powerful recoil
`force and to stand the forceful balloon inflation performed to
`deploy the valve and to embed it in the aortic annulus,
`comprises a collapsible valvular structure and an expandable
`frame on which said valvular structure is mounted. The
`valvular structure is composed of physiologically compat-
`ible valvular tissue that is sufficiently supple and resistant to
`allow the valvular structure to be deformed from a closed
`state to an opened state. The valvular tissue forms a con-
`tinuous surface and is provided with strut members that
`create stiffened zones which induce the valvular structure to
`follow a patterned movement in its expansion to its opened
`state and in its turning back to its closed state.
`
`13
`
`19
`
`Page 1 of 32
`
`Edwards Lifesciences v. Boston Scientific Scimed
`IPR2017-01293, U.S. Patent 8,992,608
`Exhibit 2012
`
`

`

`Patent Application Publication Jan. 16, 2003 Sheet 1 of 18 (cid:9)
`
`US 2003/0014104 Al
`
`FIG is
`
`FIG.lb
`
`Page 2 of 32
`
`

`

`Patent Application Publication Jan. 16, 2003 Sheet 2 of 18 (cid:9)
`
`US 2003/0014104 Al
`
`1 0 --\ 1/4
`
`11
`
`10
`
`RE.2a
`
`FIG.2b
`
`Page 3 of 32
`
`

`

`Patent Application Publication Jan. 16, 2003 Sheet 3 of 18 (cid:9)
`
`US 2003/0014104 Al
`
`10
`
`12
`
`FIG...3a
`
`,11
`FIG..3b
`
`Page 4 of 32
`
`

`

`Patent Application Publication Jan. 16, 2003 Sheet 4 of 18 (cid:9)
`
`US 2003/0014104 Al
`
`13 '2,....-v.
`
`10
`IS
`
`FIG.4a
`
`13
`
`19
`
`FIG...413
`
`Page 5 of 32
`
`

`

`Patent Application Publication Jan. 16, 2003 Sheet 5 of 18 (cid:9)
`
`US 2003/0014104 Al
`
`X'1
`
`13
`
`18
`
`17
`
`18
`
`10
`
`xl "
`FIG.5a
`
`19
`
`14
`
`FIG.5b
`
`Page 6 of 32
`
`

`

`Patent Application Publication Jan. 16, 2003 Sheet 6 of 18 (cid:9)
`
`US 2003/0014104 Al
`
`11
`
`14
`
`dlism•••
`
`4•••••
`
`F1G.7
`
`18 (cid:9)
`
`/9
`
`FIG_6a
`
`18
`
`10
`
`FIG-6b
`
`5w
`
`19
`
`10
`
`is (cid:9)
`
`19
`Fla.&
`
`Page 7 of 32
`
`

`

`Patent Application Publication Jan. 16, 2003 Sheet 7 of 18 (cid:9)
`
`US 2003/0014104 Al
`
`'79
`
`.........,..,10
`
`4"
`
`Al
`18
`FIG..8a
`
`Fla..8b
`
`Page 8 of 32
`
`

`

`Patent Application Publication Jan. 16, 2003 Sheet 8 of 18 (cid:9)
`
`US 2003/0014104 Al
`
`
`
`19
`
`1•
`
` (cid:9)
`
`x
`FIG.9a
`
`AP (cid:9)
`
`NIP
`
`14
`
`70
`
`FIG.9b
`
`21
`
`21
`
`Page 9 of 32
`
`

`

`Patent Application Publication Jan. 16, 2003 Sheet 9 of 18 (cid:9)
`
`US 2003/0014104 Al
`
`22
`
`FIG.10a
`
`10
`
`Flawl0b
`
`Page 10 of 32
`
`

`

`Patent Application Publication Jan. 16, 2003 Sheet 10 of 18 US 2003/0014104 Al
`
`24
`
`10
`
`FIG.119
`
`do
`
`FIC...11c.
`
`1:
`
`RIC_ If d
`
`F16_11 e
`
`23
`
`_4 0
`
`Page 11 of 32
`
`(cid:9)
`

`

`Patent Application Publication Jan. 16, 2003 Sheet 11 of 18 US 2003/0014104 Al
`
`11
`
`19 (cid:9)
`
`" F1G.12b
`
`26
`
`14
`
`Page 12 of 32
`
`

`

`Patent Application Publication Jan. 16, 2003 Sheet 12 of 18 US 2003/0014104 Al
`
`Page 13 of 32
`
`

`

`Patent Application Publication Jan. 16, 2003 Sheet 13 of 18 US 2003/0014104 Al
`
`Page 14 of 32
`
`

`

`Patent Application Publication Jan. 16, 2003 Sheet 14 of 18 US 2003/0014104 Al
`
`Page 15 of 32
`
`

`

`Patent Application Publication Jan. 16, 2003 Sheet 15 of 18 US 2003/0014104 Al
`
`Page 16 of 32
`
`

`

`Patent Application Publication Jan. 16, 2003 Sheet 16 of 18 US 2003/0014104 Al
`
`F16.14
`
`40
`
`Page 17 of 32
`
`

`

`Patent Application Publication Jan. 16, 2003 Sheet 17 of 18 US 2003/0014104 Al
`
`Page 18 of 32
`
`

`

`Patent Application Publication Jan. 16, 2003 Sheet 18 of 18 US 2003/0014104 Al
`
`QJ
`L-r-r
`
`Page 19 of 32
`
`

`

`US 2003/0014104 Al (cid:9)
`
`Jan. 16, 2003
`
`1
`
`VALUE PROSTHESIS FOR IMPLANTATION IN
`BODY CHANNELS
`
`CROSS-REFERENCE TO RELATED
`APPLICATIONS
`
`[0001] This application is a continuation of co-pending
`U.S. patent application Ser. No. 09/795,803, filed Feb. 28,
`2001, which in turn is a continuation of U.S. patent appli-
`cation Ser. No. 09/345,924, filed Jun. 30, 1999, now aban-
`doned, which is a National Phase filing of PCT patent
`application No. PCT/EP 97/07337, filed Dec. 31, 1997 and
`designating the United States, all of which are incorporated
`herein by reference.
`
`BACKGROUND OF THE INVENTION
`
`[0002] The present invention relates to a valve prosthesis
`for implantation in body channels, more particularly but not
`only to, cardiac valve prosthesis to be implanted by a
`transcutaneous catheterization technique.
`
`[0003] The valve prosthesis can be also applied to other
`body channels provided with native valves, such as veins or
`in organs (liver, intestine, urethra . . . ).
`
`[0004] The present invention also relates to a method for
`implanting a valve prosthesis, such as the valve according to
`the present invention.
`
`[0005] Implantable valves, which will be indifferently
`designated hereafter as "IV", "valve prosthesis" or "pros-
`thetic valve", permits the reparation of a valvular defect by
`a less invasive technique in place of the usual surgical valve
`implantation which, in the case of valvular heart diseases,
`requires thoracotomy and extracorporeal circulation. A par-
`ticular use for the IV concerns patients who cannot be
`operated on because of an associated disease or because of
`very old age or also patients who could be operated on but
`only at a very high risk.
`
`[0006] Although the IV of the present invention and the
`process for implanting said IV can be used in various heart
`valve diseases, the following description will first concern
`the aortic orifice in aortic stenosis, more particularly in its
`degenerative form in elderly patients.
`
`[0007] Aortic stenosis is a disease of the aortic valve in the
`left ventricle of the heart. The aortic valvular orifice is
`normally capable of opening during systole up to 4 to 6 cm2,
`therefore allowing free ejection of the ventricular blood
`volume into the aorta. This aortic valvular orifice can
`become tightly stenosed, and therefore the blood cannot
`anymore be freely ejected from the left ventricle. In fact,
`only a reduced amount of blood can be ejected by the left
`ventricle which has to markedly increase the intra-cavitary
`pressure to force the stenosed aortic orifice. In such aortic
`diseases, the patients can have syncope, chest pain, and
`mainly difficulty in breathing. The evolution of such a
`disease is disastrous when symptoms of cardiac failure
`appear, since 50% of the patients die in the year following
`the first symptoms of the disease.
`
`[0008] The only commonly available treatment is the
`replacement of the stenosed aortic valve by a prosthetic
`valve via surgery: this treatment moreover providing excel-
`lent results. If surgery is impossible to perform, i.e., if the
`patient is deemed inoperable or operable only at a too high
`
`surgical risk, an alternative possibility is to dilate the valve
`with a balloon catheter to enlarge the aortic orifice. Unfor-
`tunately, a good result is obtained only in about half of the
`cases and there is a high restenosis rate, i.e., about 80% after
`one year.
`
`[0009] Aortic stenosis is a very common disease in people
`above seventy years old and occurs more and more fre-
`quently as the subject gets older. As evidenced, the present
`tendency of the general evolution of the population is
`becoming older and older. Also, it can be evaluated, as a
`crude estimation, that about 30 to 50% of the subjects who
`are older than 80 years and have a tight aortic stenosis, either
`cannot be operated on for aortic valve replacement with a
`reasonable surgical risk or even cannot be considered at all
`for surgery.
`
`[0010]
`It can be estimated that, about 30 to 40 persons out
`of a million per year, could benefit from an implantable
`aortic valve positioned by a catheterization technique. Until
`now, the implantation of a valve prosthesis for the treatment
`of aortic stenosis is considered unrealistic to perform since
`it is deemed difficult to superpose another valve such an
`implantable valve on the distorted stenosed native valve
`without excising the latter.
`
`[0011] From 1985, the technique of aortic valvuloplasty
`with a balloon catheter has been introduced for the treatment
`of subjects in whom surgery cannot be performed at all or
`which could be performed only with a prohibitive surgical
`risk. Despite the considerable deformation of the stenosed
`aortic valve, commonly with marked calcification, it is often
`possible to enlarge significantly the aortic orifice by balloon
`inflation, a procedure which is considered as low risk.
`
`[0012] However, this technique has been abandoned by
`most physicians because of the very high restenosis rate
`which occurs in about 80% of the patients within 10 to 12
`months. Indeed, immediately after deflation of the balloon,
`a strong recoil phenomenon often produces a loss of half or
`even two thirds of the opening area obtained by the inflated
`balloon. For instance, inflation of a 20 mm diameter balloon
`in a stenosed aortic orifice of 0.5 cm2 area gives, when
`forcefully and fully inflated, an opening area equal to the
`cross sectional area of the maximally inflated balloon, i.e.,
`about 3 cm2. However, measurements performed a few
`minutes after deflation and removal of the balloon have only
`an area around 1 cm2 to 1.2 cm2. This is due to the
`considerable recoil of the fibrous tissue of the diseased
`valve. The drawback in this procedure has also been clearly
`shown on fresh post mortem specimens.
`
`[0013] However, it is important to note that whereas the
`natural normal aortic valve is able to open with an orifice of
`about 5 to 6 cm2 and to accommodate a blood flow of more
`that 151/min. during heavy exercise for instance, an opening
`area of about 1.5 to 2 cm2 can accept a 6 to 8 1/min blood
`flow without a significant pressure gradient. Such a flow
`corresponds to the cardiac output of the elderly subject with
`limited physical activity.
`
`[0014] Therefore, an IV would not have to produce a large
`opening of the aortic orifice since an opening about 2 cm2
`would be sufficient in most subjects, in particular in elderly
`subjects, whose cardiac output probably does not reach more
`than 6 to 8 1/min. during normal physical activity. For
`instance, the surgically implanted mechanical valves have
`
`Page 20 of 32
`
`

`

`US 2003/0014104 Al (cid:9)
`
`Jan. 16, 2003
`
`2
`
`an opening area which is far from the natural valve opening
`that ranges from 2 to 2.5 cm2, mainly because of the room
`taken by the large circular structure supporting the valvular
`part of the device.
`[0015] The prior art describes examples of cardiac valves
`prosthesis that are aimed at being implanted without surgical
`intervention by way of catheterization. For instance, U.S.
`Pat. No. 5,411,552 describes a collapsible valve able to be
`introduced in the body in a compressed presentation and
`expanded in the right position by balloon inflation.
`[0016] Such valves, with a semi-lunar leaflet design, tend
`to imitate the natural valve. However, this type of design is
`inherently fragile, and such structures are not strong enough
`to be used in the case of aortic stenosis because of the strong
`recoil that will distort this weak structure and because they
`would not be able to resist the balloon inflation performed to
`position the implantable valve. Furthermore, this valvular
`structure is attached to a metallic frame of thin wires that
`will not be able to be tightly secured against the valve
`annulus. The metallic frame of this implantable valve is
`made of thin wires like in stents, which are implanted in
`vessels after balloon dilatation. Such a light stent structure
`is too weak to allow the implantable valve to be forcefully
`embedded into the aortic annulus. Moreover, there is a high
`risk of massive regurgitation (during the diastolic phase)
`through the spaces between the frame wires which is another
`prohibitive risk that would make this implantable valve
`impossible to use in clinical practice.
`
`[0017] Furthermore, an important point in view of the
`development of the IV is that it is possible to maximally
`inflate a balloon placed inside the compressed implantable
`valve to expand it and insert it in the stenosed aortic valve
`up to about 20 to 23 mm in diameter. At the time of
`maximum balloon inflation, the balloon is absolutely stiff
`and cylindrical without any waist. At that moment, the
`implantable valve is squeezed and crushed between the
`strong aortic annulus and the rigid balloon with the risk of
`causing irreversible damage to the valvular structure of the
`implantable valve.
`
`SUMMARY OF THE INVENTION
`
`[0018] The invention is aimed to overcome these draw-
`backs and to implant an IV which will remain reliable for
`years.
`
`[0019] A particular aim of the present invention is to
`provide an IV, especially aimed at being used in case of
`aortic stenosis, which structure is capable of resisting the
`powerful recoil force and to stand the forceful balloon
`inflation performed to deploy the IV and to embed it in the
`aortic annulus.
`
`[0020] Another aim of the present invention is to provide
`an efficient prosthesis valve which can be implanted by a
`catheterization technique, in particular in a stenosed aortic
`orifice, taking advantage of the strong structure made of the
`distorted stenosed valve and of the large opening area
`produced by preliminary balloon inflation, performed as an
`initial step of the procedure.
`
`[0021] A further aim of the present invention is to provide
`an implantable valve which would not produce any risk of
`fluid regurgitation.
`
`[0022] A further aim of the present invention is to provide
`a valve prosthesis implantation technique using a two-
`balloon catheter and a two-frame device.
`[0023] These aims are achieved according to the present
`invention which provides a valve prosthesis of the type
`mentioned in the introductory part and wherein said valve
`prosthesis comprises a collapsible continuous structure with
`guiding means providing stiffness and a frame to which said
`structure is fastened, said frame being strong enough to
`resist the recoil phenomenon of the fibrous tissue of the
`diseased valve.
`[0024] The IV, which is strongly embedded, enables the
`implantable valve to be maintained in the right position
`without any risk of further displacement, which would be a
`catastrophic event.
`[0025] More precisely, this valvular structure comprises a
`valvular tissue compatible with the human body and blood,
`which is supple and resistant to allow said valvular structure
`to pass from a closed state to an open state to allow a body
`fluid, more particularly the blood, exerting pressure on said
`valvular structure, to flow. The valvular tissue forms a
`continuous surface and is provided with guiding means
`formed or incorporated within, creating stiffened zones
`which induce the valvular structure to follow a patterned
`movement from its open position to its closed state and
`vice-versa, providing therefore a structure sufficiently rigid
`to prevent diversion, in particular into the left ventricle and
`thus preventing any regurgitation of blood into the left
`ventricle in case of aortic implantation.
`[0026] Moreover, the guided structure of the IV of the
`invention allows the tissue of this structure to open and close
`with the same patterned movement while occupying as little
`space as possible in the closed state of the valve. Therefore,
`owing to these guiding means, the valvular structure with-
`stands the unceasing movements under blood pressure
`changes during the heart beats.
`[0027] More preferably, the valvular structure has a sub-
`stantially truncated hyperboloidal shape in its expanded
`position, with a larger base and a growing closer neck,
`ending in a smaller extremity forming the upper part of the
`valvular structure. The valvular structure has a curvature at
`its surface that is concave towards the aortic wall. Such a
`shape produces a strong and efficient structure in view of the
`systolo-diastolic movement of the valvular tissue. Such a
`valvular structure with its simple and regular shape also
`lowers the risk of being damaged by forceful balloon
`inflation at the time of IV deployment.
`[0028] A trunco-hyperboloidal shape with a small diam-
`eter at the upper extremity facilitates the closure of the valve
`at the beginning of diastole in initiating the starting of the
`reverse movement of the valvular tissue towards its base.
`Another advantage of this truncated hyperboloidal shape is
`that the upper extremity of the valvular structure, because of
`its smaller diameter, remains at a distance from the coronary
`ostia during systole as well as during diastole, thus offering
`an additional security to ensure not to impede at all the
`passage of blood from the aorta to the coronary ostia.
`[0029] As another advantageous embodiment of the
`invention, the guiding means of the valvular structure are
`inclined strips from the base to the upper extremity of the
`valvular structure with regard to the central axis of the
`
`Page 21 of 32
`
`

`

`US 2003/0014104 Al (cid:9)
`
`Jan. 16, 2003
`
`3
`
`valvular structure. This inclination initiates and imparts a
`general helicoidal movement of the valvular structure
`around said central axis at the time of closure or opening of
`said structure, such a movement enabling to help initiate and
`finalize the closure of the valvular structure. In particular,
`this movement improves the collapse of the valvular struc-
`ture towards its base at the time of diastole and during the
`reversal of flow at the very beginning of diastole. During
`diastole, the valvular structure thus fails down, folding on
`itself and collapses on its base, therefore closing the aortic
`orifice. The strips can be pleats, strengthening struts or
`thickened zones.
`
`[0030] In other embodiments, said guiding means are
`rectilinear strips from the base to the upper extremity of the
`valvular structure. In this case, the guiding means can
`comprise pleats, struts or thickened zones. In a particular
`embodiment, the stiffened zones then created can be advan-
`tageously two main portions, trapezoidal in shape, formed
`symmetrically one to each other with regard to the central
`axis of the valvular structure, and two less rigid portions
`separating said two main portions to lead to a tight closeness
`in shape of a closed slot at the time of closure of the upper
`extremities of the main portions of the valvular structure.
`The thickened zones can be extended up to form the stiff-
`ened zones.
`
`[0031] More particularly, each of said main slightly rigid
`portions occupy approximately one third of the circumfer-
`ence of the valvular structure when this latter is in its open
`position. The slightly rigid portions maintain the valvular
`structure closed during diastole by firmly applying them-
`selves on each other. The closure of the valvular structure at
`the time of diastole thus does not have any tendency to
`collapse too much towards the aortic annulus.
`
`[0032] Preferably, the guiding means are a number of
`pleats formed within the tissue by folding, or formed by
`recesses or grooves made in the tissue. The shape of the
`pleats is adapted to achieve a global shape of the desired
`type for said position.
`
`[0033] Alternatively, the guiding means are made of
`strengthening struts, preferably at least three, incorporated in
`the tissue in combination or not with said pleats.
`
`[0034] The guiding means and, in particular, the strength-
`ening struts, help to prevent the valvular tissue from col-
`lapsing back too much and to reverse inside the left ventricle
`through the base of the frame, preventing the risk of blood
`regurgitation.
`
`In a preferred prosthetic valve of the invention, said
`[0035]
`valvular tissue is made of synthetic biocompatible material
`such as TEFLON® or DACRON®, polyethylene, polya-
`mide, or made of biological material such as pericardium,
`porcine leaflets and the like. These materials are commonly
`used in cardiac surgery and are quite resistant, particularly to
`folding movements due to the increasing systolo-diastolic
`movements of the valvular tissue and particularly at the
`junction with the frame of the implantable valve.
`
`[0036] The valvular structure is fastened along a substan-
`tial portion of an expandable frame, by sewing, by molding
`or by gluing to exhibit a tightness sufficiently hermetical to
`prevent any regurgitation of said body fluid between the
`frame and the valvular structure.
`
`[0037] Preferably, an internal cover is coupled or is inte-
`gral to the valvular structure and placed between said
`valvular structure and the internal wall of the frame to
`prevent any passage of the body fluid through said frame.
`Therefore, there is no regurgitation of blood as it would be
`the case if there were any space between the valvular
`structure fastened on the frame and the zone of application
`of the frame on the aortic annulus. The internal cover makes
`a sort of "sleeve" at least below the fastening of the valvular
`structure covering the internal surface of the frame and thus
`prevents any regurgitation of blood through the frame.
`
`In the present invention, the frame is a substantially
`[0038]
`cylindrical structure capable of maintaining said body chan-
`nel open in its expanded state and supporting said collaps-
`ible valvular structure.
`
`[0039] In a preferred embodiment of the invention, the
`frame is made of a material which is distinguishable from
`biological tissue to be easily visible by non invasive imaging
`techniques.
`
`[0040] Preferably, said frame is a stainless metal structure
`or a foldable plastic material, made of intercrossing, pref-
`erably with rounded and smooth linear bars. This frame is
`strong enough to resist the recoil phenomenon of the fibrous
`tissue of the diseased valve. The size of the bars and their
`number are determined to give both the maximal rigidity
`when said frame is expanded and the smallest volume when
`the frame is compressed.
`
`[0041] More preferably, the frame has projecting curved
`extremities and presents a concave shape. This is aimed at
`reinforcing the embedding and the locking of the implant-
`able valve in the distorted aortic orifice.
`
`In a preferred embodiment of the present invention,
`[0042]
`the IV is made in two parts, a first reinforced frame coupled
`with a second frame which is made of thinner bars than said
`first frame and which is embedded inside the second frame.
`This second frame to which the valvular structure is fastened
`as described above, is preferably less bulky than the first
`frame to occupy as little space as possible and to be easily
`expanded using low pressure balloon inflation.
`
`[0043] The present invention also relates to a double
`balloon catheter to separately position the first frame in the
`dilated stenosed aortic valve and place the second frame that
`comprises the valvular structure. This catheter comprises
`two balloons fixed on a catheter shaft and separated by few
`centimeters.
`
`[0044] The first balloon is of the type sufficiently strong to
`avoid bursting even at a very high pressure inflation and is
`aimed at carrying, in its deflated state, a strong frame aimed
`at scaffolding the previously dilated stenosed aortic valve.
`The second balloon is aimed at carrying the second frame
`with the valvular structure.
`
`[0045] An advantage of this double balloon catheter is that
`each balloon has an external diameter which is smaller than
`known balloons since each element to be expanded is
`smaller.
`
`[0046] Moreover, such a double balloon catheter allows to
`enlarge the choice for making an efficient valvular structure
`enabling to overcome the following two contradictory con-
`ditions:
`
`Page 22 of 32
`
`

`

`US 2003/0014104 Al (cid:9)
`
`Jan. 16, 2003
`
`4
`
`[0047] 1) having a soft and mobile valvular structure
`capable of opening and closing freely in the blood
`stream, without risk of being damaged by balloon
`inflation; and
`
`[0048] 2) needing a very strong structure able to
`resist the recoil force of the stenosed valve and
`capable of resisting, without any damage, a strong
`pressure inflation of the expanding balloon.
`
`[0049] Furthermore, the shaft of said double balloon cath-
`eter comprises two lumens for successive and separate
`inflation of each balloon. Of note, an additional lumen
`capable of allowing a rapid inflation takes additional room
`in the shaft.
`
`[0050] The invention also relates to a method of using a
`two-balloon catheter with a first frame and second frame to
`which a valve prosthesis of the type previously described is
`fastened.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`[0051] The invention will now be explained and other
`advantages and features will appear with reference to the
`accompanying schematical drawings wherein:
`
`[0052] FIGS. la, lb and lc illustrate, in section views,
`respectively, the normal aortic valve in systole, in diastole
`and a stenosed aortic valve;
`
`[0053] FIGS. 2a and 2b illustrate two examples of a
`metallic frame which are combined to a valvular structure
`according to the present invention;
`
`[0054] FIGS. 3a and 3b illustrate a frame according to the
`invention in its expanded position with an opening out of the
`extremities, respectively, with a cylindrical and a concave
`shape;
`
`[0055] FIGS. 4a and 4b illustrate an IV of the invention
`respectively in its compressed position and in its expanded
`position in an open position as in systole;
`
`[0056] FIGS. 5a and 5b illustrate respectively an IV of the
`invention in its closed position and a sectional view accord-
`ing to the central axis of such a valvular structure which is
`closed as in diastole;
`
`[0057] FIGS. 6a to 6d illustrate a sectional view accord-
`ing to the central axis of an IV according to the present
`invention and showing the internal cover and the external
`cover of the valvular structure overlapping partially or non
`overlapping the frame bars;
`
`[0058] FIG. 7 illustrates the frontal zig-zag fastening line
`of the valvular tissue on the frame;
`
`[0059] FIGS. 8a and 8b illustrate, respectively, a perspec-
`tive view of a valvular structure and an internal cover made
`all of one piece and a perspective view of the corresponding
`frame into which they will be inserted and fastened;
`
`[0060] FIGS. 9a and 9b illustrate inclined strengthening
`struts, an example of a valvular structure according to the
`invention, respectively in the open position and in the closed
`position;
`
`[0061] FIGS. 10a and 10b illustrate an example of a
`valvular structure comprising pleats, respectively in the
`open and in the closed position;
`
`[0062] FIGS. lla and llb illustrate a valvular structure
`comprising two trapezoidal slightly rigid portions, respec-
`tively in the open and in the closed position;
`
`[0063] FIGS. llc to lle illustrate a valvular structure
`comprising a rectangular stiffened zone, respectively in the
`open, intermediate and closed position;
`
`[0064] FIGS. 12a and 12b illustrate, respectively, a per-
`spective and cross sectional views of an implantable valve in
`its compressed presentation squeezed on a balloon catheter;
`
`[0065] FIGS. 13a to 13/ illustrate views of the successive
`procedure steps for the IV implantation in a stenosed aortic
`orifice;
`
`[0066] FIG. 14 illustrates an implantable valve made in
`two parts in its compressed presentation squeezed on a
`two-balloon catheter with a reinforced frame on a first
`balloon and with the implantable valve on the second
`balloon; and
`
`[0067] FIGS. 15a to 15f illustrate the successive steps of
`the implantation of the implantation valve in two parts with
`a two-balloon catheter.
`
`DETAILED DESCRIPTION OF THE
`PREFERRED EMBODIMENTS
`
`[0068] In the diastole and systole illustrations of section
`views of FIGS. la and lb, the arrows A indicates the general
`direction of the blood flow. The semi-lunar leaflets 1 and 2
`of a native aortic valve (with only two out of three shown
`here) are thin, supple and move easily 20 from the com-
`pletely open position (systole) to the closed position (dias-
`tole). The leaflets originate from an aortic annulus 2a.
`
`[0069] The leaflets 1' and 2' of a stenosed valve as illus-
`trated in FIG. lc, are thickened, distorted, calcified and
`more or less fused, leaving only a small hole or a narrow slit
`3, which makes the ejection of blood from the left ventricle
`cavity 4 into the aorta 5 difficult and limited. FIGS. la to lc
`show also the coronary artery ostium 6a and 6b and FIG. 1
`a shows, in particular, the mitral valve 7 of the left ventricle
`cavity 4.
`
`[0070] An implantable valve according to the invention
`essentially comprises a supple valvular structure supported
`by a strong frame. The positioning of the implantable valve
`is an important point since the expanded frame has to be
`positioned exactly at the level of the native valvular leaflets
`1, 2 of the native valve, the structures of which are pushed
`aside by the inflated balloon.
`
`[0071] Ideally, the implantable valve is positioned with the
`fastening line of the valvular structure on the frame exactly
`on the remains of the crushed stenosed valve to prevent any
`regurgitation of blood. In practice, it is difficult to position
`the implantable valve within less than 2 or 3 mm. However,
`any risk of regurgitation of blood is eliminated with the
`presence of an internal cover, as will be described below.
`
`[0072] The upper limit of the frame should be placed
`below the opening of the coronary arteries, i.e., the coronary
`ostia 6, or at their level so that the frame does not impede
`free blood flow in the coronary arteries. This point is a
`delicate part of positioning an IV since the distance between
`the superior limit of the leaflets of the natural valve and the
`coronary ostia 6 is only about 5 to 6 mm. However, the ostia
`
`Page 23 of 32
`
`

`

`US 2003/0014104 Al (cid:9)
`
`Jan. 16, 2003
`
`5
`
`are located in the Valsalva sinus 8 which constitutes a hollow
`that are located a little out of the way. This helps to prevent
`from impeding the coronary blood flow by the IV.
`
`[0073] At the time of implantation, the operator evaluates
`the exact positioning of the coronary ostia by looking at the
`image produced by a sus-valvular angiogram with contrast
`injection performed before the implantation procedure. This
`image will be fixed in the same projection on a satellite TV
`screen and will permit the evaluation of the level of the
`origin of the right and left coronary arteries. Possibly, in case
`the ostia are not clearly seen by sus-valvular angiography, a
`thin guide wire, as those used in coronary angioplasty, is
`positioned in each of the coronary arteries to serve as a
`marker of the coronary ostia.
`
`[0074] The lower part of the frame of the IV preferably
`extends by 2 or 3 mm inside the left ventricle 4, below the
`aortic annulus 2a. However, this part of the frame should not
`reach the insertion of the septal leaflet of the mitral valve 7,
`so that it does not interfere with its movements, particularly
`during diastole.
`
`[0075] FIGS. 2a and 2b show respectively an example of
`a cylindrical frame or stent 10 comprising intercrossing
`linear bars 11, with two intersections I by bar 11, the bars 11
`being soldered or provided from a folded wire to constitute
`the frame, with for instance a 20 mm, 15 mm or 12 mm
`height, and an example with only one intersection of bars 11.
`Preferably, such a frame is expandable from a size of about
`4 to 5 millimeters to a size of about 20 to 25 mm in diameter,
`or even to about 30-35 mm (or more) in particular cases, for
`instance for the mitral valve. Moreover, said frame, in its
`fully expanded state, has a height of approximately between
`10 and 15 mm and in its fully compressed frame, a height of
`a