.
`
`Ulllt?d States Patent [19]
`Teitelbaum
`
`USOO5332402A
`
`[11] Patent Number:
`[45] Date of Patent:
`
`5,332,402
`Jul. 26, 1994
`
`[54] PERCUTANEOUSLY-INSERTED CARDIAC
`
`3,911,502 10/1975 Boretos ................................. .. 623/2
`
`VALVE
`
`[76] Inventor: George P- Teitelbaum, 12138 Laurel
`
`Terrace Dr., Studio City, Calif.
`92604
`[21] Appl. No.: 881,969
`[22] Filed:
`May 12, 1992
`
`4,030,142 6/1977 Wolfe . . . . .
`
`4,503,569 3/1985 Dotter
`4,759,758 7/1988 Gabbay . . . . . .
`
`. . . . . . . . .. 623/2
`
`604/8X
`. . . . . . . . .. 623/2
`
`4,994,077 2/1991 Dobben . . . . . .
`Primary Examiner-—Randa1l L. Green
`Assistant Examiner-Mary Beth Jones
`Attorney, Agent, or Fzrm-James H. Laughlin, Jr.
`
`. . . . .. 623/2
`
`[51] Int. 0.5 .............................................. .. A61F 2/24
`[52] US. Cl. ....................................... .. 623/2; 623/900
`[58] Field of Search .................................. .. 623/2, 900
`.
`References cued
`U.S. PATENT DOCUMENTS
`3,626,518 12/1971 Leibinsohn ........................... .. 623/2
`
`[56]
`
`ABSTRACT
`[57]
`A cardiac valve implanted within the heart is given
`where a expansible valve maintained in a collapsed form
`by cold temperature is percutaneously inserted along a
`releasable guide wire in a cooled sheath and when posi
`tioned is expanded by withdrawing the cold tempera
`“Ire
`
`3,691,567 9/1972 Cromie . . . . . . . . . . . .
`
`. . . . . . .. 623/2
`
`3,868,956 3/1975 Al?di et a1. ....................... .. 606/194
`
`8 Claims, 2 Drawing Sheets
`
`Edwards Exhibit 1038, pg. 1
`
`

`
`US. Patent
`
`July 26, 1994
`
`Sheet 1 0f 2
`
`5,332,402
`
`Edwards Exhibit 1038, pg. 2
`
`

`
`US. Patent
`
`July 26, 1994
`
`Sheet 2 of 2
`
`5,332,402
`
`Edwards Exhibit 1038, pg. 3
`
`

`
`1
`
`PERCUTANEOUSLY-INSERTED CARDIAC
`VALVE
`
`5
`
`15
`
`20
`
`25
`
`30
`
`5,332,402
`2
`regurgitant) cardiac valve. The device is inserted percu
`taneously via an appropriately sized small sheath, such
`as, for example, a 14F sheath using the jugular venous
`routes. The sheath is positioned to extend across the
`interatrial septum.
`The device is fabricated from a “shaped memory”
`alloy, nitinol, which is composed of nickel and titanium.
`Nitinol wire is ?rst fashioned into the desired shape for
`the device and then the device is heat annealed. When
`the components of the valve are then exposed to ice
`cold temperatures, they become very ?exible and sup
`ple, allowing them to be compressed down and pass
`easily through the delivery sheath. A cold temperature
`is maintained within the sheath during delivery to the
`deployment site by constantly infusing the sheath with
`an iced saline solution. Once the valve components are
`exposed to body temperature at the end of the sheath,
`they instantaneously reassume their predetermined
`shapes, thus allowing them to function as designed.
`The percutaneous cardiac valve has two possible
`designs, each of which consists of two components. In
`the ?rst design, one of the components is a meshwork of
`nitinol wire of approximately 0.008 inch gauge formed
`into a tubular structure with a minimum central diame
`ter of 20 min. Away from its central portion, the tubular
`structure ?ares markedly at both ends in a trumpet-like
`con?guration. The maximum longitudinal dimension of
`this component which shall be referred to as the stent or
`doubly-?ared stent is approximately 20 mm. The maxi
`mum diameter of the ?ared ends of the stent is approxi
`mately 30 mm. The purpose of the stent is to maintain a
`semi-rigid patent channel through the diseased cardiac
`valve following its balloon dilation. The ‘?ared ends of
`the stent maintain the position of this component across
`the native valve following deployment. The stent con
`tains a thin hydrophilic plastic coating that helps pre
`vent thrombus formation along the inner surface of the
`stent.
`In the second component of the ?rst percutaneous
`cardiac valve designis referred to as the sliding obtura
`tor. At one end of this component are two nitinol wires
`of 0.038 inch diameter which are fashioned into dual
`loops a right angles to one another. At the other end
`these dual wires are connected to an umbrella-shaped
`structure composed of small, thin slats of nitinol metal
`covered by silicone rubber with a hydrophilic coating.
`The dual wires and umbrella structure can be com
`pressed down so as to ?t through a 14F delivery sheath
`with continuous ?ushing of this sheath with ice-cold
`heparinized saline. When exposed to body temperature
`at the end of the delivery sheath, the sliding obturator
`will expand to its functional size, with a ?nal umbrella
`diameter of 20—25 mm.
`The sliding obturator will be deployed within the
`expanded stent. The loop formed by the dual wires of
`the sliding obturator will have sufficient diameter so as
`not to allow the sliding obturator being carried away by
`the force of blood ?ow. The umbrella portion of the
`sliding obturator will ?air out so that its widest diame
`ter will face the interior of the cardiac ventricle. This
`will allow the sliding obturator to ‘move forward during
`diastole (relaxation of the heart), thus opening the valve
`and allowing ?lling of the ventricle. However, during
`systole (contraction of the heart), when there is mark
`edly increased intraventricular pressure, the force of
`blood will act against the open or widest portion of the
`umbrella pushing back against the ?ared opening of the
`
`BACKGROUND OF THE INVENTION
`‘1. FIELD OF THE INVENTION
`This invention relates to cardiac valvular surgery
`techniques for replacement of diseased cardiac valves.
`More particularly, this invention relates to materials
`and techniques for replacement of diseased mitral
`valves in humans as well as other animals.
`2. PRIOR ART
`Cardiac valvular surgery is performed in cases where
`there is a diminished ?ow area within a cardiac valve
`which results in a blockage of normal ?ow. This block
`age leads to cardiac failure. Cardiac valvular surgery
`may also be required in cases of valvular incompetence
`in which back ?ow of blood occurs across a valve that
`cannot close fully. This is also known as valvular regur
`gitation Each of the above conditions are frequently
`due to rheumatic heart disease. Replacement of stenotic
`or narrowed cardiac valves and regurgitant or incom
`petent cardiac valves requires open-heart surgery
`which utilizes a heart-lung machine.
`Expansible devices for implantation have been
`known by the medical community. These devices in
`clude, for example, the so-called recovery metals such
`as titanium-nickel equiatomic intermetallic compounds
`which demonstrate mechanica “memory” whereby
`after being formed into speci?c shapes, these metals are
`compressed or otherwise given temporary different
`shapes for insertion and thereafter, when in place, are
`expanded whereby their mechanical “memory” of the
`originally formed shape causes the device to assume its
`originally formed shape.
`Materials which are known for having properties
`useful in such systems include nickel based alloys such
`as those described in US. Pat. No. 3,174,851. Typically,
`these materials comprise 52 to 56 percent nickel by
`weight with the remainder being titanium. An initial
`shape may be permanently set into such recovery metals
`by heating them while they are held in the desired con
`?guration. The forming temperature for setting the
`initial shape into the described titanium-nickel alloy is
`typically about 930° F. The alloy is then cooled and
`thereafter deformed plastically to a deformed con?gu
`ration which can be retained until the alloy is reheated
`to a transition temperature whereafter the alloy will
`recover its initial con?guration.
`Various implantable appliances have been described
`in the patent literature. For example, U.S. Pat. No.
`3,868,956 uses an expansible appliance implanted with a
`vessel through a catheter involving a positioning de
`vice. The positioning device is complex because it re
`quires the use of electrical conductors to heat the expan
`sible appliance to allow it to function. US. Pat. No.
`4,503,569 positions and expands a graft prosthesis using
`hot saline.
`Generally, the known art applies these techniques to
`the repair of blood vessels narrowed or occluded by
`disease.
`If a satisfactory means could be devised of replacing
`diseased cardiac valves percutaneously, many major
`open-heart surgeries could be avoided.
`
`35
`
`45
`
`55
`
`SUMMARY OF THE INVENTION
`This invention generally describes a device that
`serves as a replacement for a diseased (either stenotic or
`
`65
`
`Edwards Exhibit 1038, pg. 4
`
`

`
`4
`BRIEF DESCRIPTION OF THE DRAWINGS
`FIG. 1 is a cutaway portion of a heart showing the
`catheter following a guide wire entering through the
`interatrial septum.
`FIG. 2 is a cutaway portion of a heart showing the
`stent in place along the guide wire after the catheter has
`been withdrawn from the heart.
`FIG. 3 is a cutaway portion of a heart showing the
`installed cardiac valve, a sliding obturator, positioned
`within the stent.
`FIG. 4 is a perspective view of the sliding obturator
`of this invention in its expanded and normal form.
`FIG. 4A is and FIG. 4B are partial side views of the
`sliding obturator of FIG. 4 inserted and in use where
`FIG. 4A shows its position within the stent in systole
`while FIG. 4B shows its position within the stent in
`diastole.
`FIG. 5 is a perspective view of a different embodi
`ment of this invention, namely, a ball valve and stent
`design.
`FIG. 6. is a view of the ball of the ball valve of FIG.
`5 after in?ation.
`
`5,332,402
`3
`wire mesh stent, thus closing the valve. The sliding
`obturator will therefore allow blood ?ow in only one
`direction.
`The second version of the percutaneous cardiac valve
`is the ball design. In this design, the distal end of the
`wire mesh stent possesses two curved wires that extend
`beyond the stent into the ventricle, forming a cage
`structure that will house a small silicone rubber sphere
`or ball. The silicone sphere will have a hydrophilic
`coating to diminish thrombogenicity. The silicone
`sphere will be introduced de?ated attached to the end
`of an 8F catheter through the same delivery sheath used
`for the placement of the stent with the distal cage. Once
`in position within the cage, the sphere will be in?ated
`with a polymer mixture that will have a rapid set-up
`time (it will harden within minutes). After the sphere
`has been in?ated it will be separated from its delivery
`catheter and will remain in?ated due to a self-sealing
`valve at its attachment point with the delivery catheter.
`During diastole (ventricular falling stage), the sphere
`will be carried forward by blood ?ow, thus opening the
`valve. The cage will act to restrict the motion of the
`sphere, preventing it from being lost within the ventri
`cle. During systole, the sphere will be forced backwards
`due to markedly increased intraventricular pressure,
`thus closing the valve. The design of the second version
`of the percutaneous cardiac valve is similar to the Starr
`Edwards cardiac valve which also uses a ball-valve
`mechanism to allow only one-way ?ow through the
`valve.
`Both versions of the percutaneous cardiac valve are
`introduced via the right internal jugular venous ap
`proach. Following puncture of this vein, a catheter and
`needle combination are used to puncture the interatrial
`septum allowing passage of a guide wire and catheter
`from the right to the left atrium. The same catheter and
`guide wire or catheter is then ?oated with blood ?ow
`out the left ventricle and into the thoracic aorta. The
`transjugular guide wire is then captured by a snare or
`basket and dragged out through the right or left com
`mon femoral artery. In so doing, one will have control
`over both ends of the guide wire used to introduce the
`percutaneous cardiac valve. Over this guide wire, a
`high-pressure balloon catheter is advanced across the
`diseased mitral valve where it is in?ated. Once the
`valve is fully dilated, the balloon catheter is de?ated
`and replaced with a 14F delivery sheath inserted via the
`right internal jugular approach. The sheath’s tip will be
`positioned in the left ventricle. The nitinol stent (with or
`without distal cage) is advanced to the site of the dilated
`valve by means of a pusher rod. All the while, the deliv
`ery sheath is being ?ushed with cold heparinized saline
`to keep the stent compressed, soft, and ?exible. Once
`the stent has been pushed to the distal end of the sheath
`55
`where it bridges the site of the dilated valve, the pusher
`will be held steady while the sheath is withdrawn, al
`lowing the stent to come into contact with body tem
`perature. This will cause the rapid expansion of the stent
`and create an adequate ?ow lumen through the diseased
`valve.
`At this point, either the sliding obturator or the sili
`cone sphere are deployed with the appropriate valve
`stent. Since both versions of the stent have a hydro
`philic silicone coating, when the sliding obturator or
`silicone sphere come into contact with the stent lumen,
`they seal or close the valve, preventing back?ow of
`blood.
`
`50
`
`60
`
`30
`
`45
`
`DESCRIPTION OF THE PREFERRED
`EMBODIMENTS
`As noted earlier, cardiac valvular surgery is per
`formed in cases where there is a diminished ?ow area
`within a cardiac valve which results in a blockage of
`normal ?ow which can leads to cardiac failure. Surgery
`is often required in cases of valvular incompetence in
`which back ?ow of blood occurs across a valve that
`cannot close fully. Replacement of stenotic and regurgi
`tant cardiac valves can be accomplished in accordance
`with this invention using percutaneous techniques al
`lowing for avoidance of many major open-heart sur
`gery procedures.
`This invention describes a device that serves as a
`replacement for a diseased stenotic or regurgitant car
`diac valve. By this invention, a technique and the de
`vices which serve as a replacement for a stenotic or
`.regurgitant diseased cardiac valves is given. This tech
`nique and the devices employed are particularly useful
`in replacement of diseased mitral valves.
`In this invention, compressed devices are inserted
`percutaneously by way of an appropriately sized sheath
`using the jugular venous routes and expanded to form
`new valve mechanisms which provide replacement
`cardiac valves.
`The catheter and delivery sheath of this invention are
`appropriately sized for use. One such appropriate cathe
`ter is a 14F plastic catheter used for delivery and de
`ployment of both stents and the valve structures of this
`invention. Such a delivery sheath is used in the normal
`matter and may have a pusher capable of moving a stent
`or other valve part to its ultimate location in the heart.
`With reference to FIG. 1, FIG. 2 and FIG. 3, in the
`technique and procedure of this invention, the percu
`taneous cardiac valve is introduced via the right inter
`nal jugular venous approach. Following puncture of
`this vein, a catheter and needle combination (not
`shown) are used to puncture the interatrial septum 4
`allowing passage of a guide wire 8 and catheter 6 from
`the right to the left atrium. The same catheter and guide
`wire or catheter is then ?oated with blood ?ow out the
`left ventricle and into the thoracic aorta 10. The trans
`jugular guide wire is then captured by a snare or basket
`(not shown) and dragged out through the right or left
`
`Edwards Exhibit 1038, pg. 5
`
`

`
`20
`
`5,332,402
`5
`common femoral artery. This allows control over both
`ends of the guide wire used to introduce the percutane
`ous cardiac valve.
`Over the guide wire 8, a high-pressure balloon cathe
`ter (not shown) is advanced across the diseased mitral
`valve where it is in?ated. Once the valve is fully dilated,
`the balloon catheter is de?ated and replaced with a 14F
`delivery sheath 6 inserted via the right internal jugular
`approach. The sheath’s tip will be positioned in the left
`ventricle. A compressed nitinol stent, doubly-?ared
`stent 12 as shown, is advanced to the site of the dilated
`valve by means of pusher rod (not shown). All the
`while, the delivery sheath is being ?ushed with iced
`cold heparinized saline to keep the stent compressed,
`soft, and ?exible. Once the stent has been pushed to the
`distal end of the sheath 6 where it bridges the site of the
`dilated valve, the pusher will be held steady while the
`sheath is withdrawn allowing the stent to come into
`contact with body temperature. This will cause the
`rapid expansion of the stent 12 as shown in FIG. 2 and
`create a channel for adequate ?ow lumen through the
`diseased valve.
`At this point, a valve mechanism is inserted. While
`various valve mechanisms can be employed, this inven
`tion is particularly effective with a sliding obturator 14
`position as shown in FIG. 3 and shown in more detail in
`FIG. 4. Alternatively, a silicone sphere can be deployed
`with the appropriate valve stent as shown in FIG. 5.
`Since both versions of the stent have a hydrophilic
`silicone coating, when the sliding obturator or silicone
`sphere come into contact with the stent lumen, a seal is
`created when the valve is closed preventing back?ow
`of blood.
`The devices of this invention are fabricated from a
`“shaped memory” alloy, nitinol, which is composed of
`nickel and titanium. Nitinol wire is ?rst fashioned into
`the desired shape for the device and then the device is
`heat annealed. When the components of the valve are
`then exposed to ice-cold temperatures, they become
`very ?exible and supple, allowing them to be com
`pressed down and pass easily through a delivery sheath.
`Cold temperature is maintained with the sheath during
`delivery to the deployment site by constantly infusing
`the sheath with an iced saline solution. Once the valve
`components are exposed to body temperature at the end
`of the sheath, they instantaneously reassume their pre
`determined shapes, thus allowing them to function as
`designed.
`The sliding obturator cardiac valve has two compo
`nents. As shown in FIG. 2, one of the components is a
`stent 12 which comprises a meshwork of nitinol wire of
`approximately 0.008 inch gauge formed into a tubular
`structure with a minimum central diameter of 20 mm.
`Away from its central portion, the tubular structure
`55
`?ares markedly at both ends in a trumpet-like con?gura
`tion. The maximum longitudinal dimension of this stent,
`or more particularly, a doubly-?ared stent, is approxi
`mately 20 mm. The maximum diameter of the ?ared
`ends of the stent is approximately 30 mm. The purpose
`of the stent is to maintain a semi-rigid patent channel
`through the diseased cardiac valve following its balloon
`dilation as shown in FIG. 2. The ?ared ends of the stent
`maintain the position of this component across the na
`tive valve following deployment. The stent contains a
`thin hydrophilic plastic coating (not shown) that helps
`prevent thrombus formation along the inner surface of
`the stent.
`
`6
`The second component of the sliding obturator valve
`design is shown in FIG. 4. At one end of this component
`are two nitinol wires of 0.038 inch diameter which are
`fashioned into dual loops 16 and 18 at right angles to
`one another. At the other end these dual wires are con
`nected to an umbrella-shaped structure 20 composed of
`small, thin slats of nitinol metal covered by silicone
`rubber with a hydrophilic coating. The dual wires and
`umbrella structure can be compressed down so as to ?t
`through a delivery sheath with continuous ?ushing of
`this sheath with ice-cold heparinized saline. When ex
`posed to body temperature at the end of the delivery
`sheath, the sliding obturator will expand to its func
`tional size, with a ?nal umbrella diameter of 20-25 mm.
`The sliding obturator will be deployed within the
`expanded stent as shown in FIG. 4A and 4B. The loops
`16 and 18 formed by the dual wires of the sliding obtu
`rator will have sufficient diameter so as not to allow the
`sliding obturator being carried away by the force of
`blood ?ow. The umbrella portion 20 of the sliding obtu
`rator will flair out so that its widest diameter will face
`the interior of the cardiac ventricle. This will allow the
`sliding obturator to move forward during diastole or
`relaxation of the heart as shown in FIG. 4B, thus open
`ing the valve and allowing ?lling of the ventricle allow
`ing ?ow as shown by arrows. However, during systole
`or contraction of the heart, when there is markedly
`increased intraventricular pressure, the force of blood
`will act against the open or widest portion of the um
`brella 20 as shown in FIG. 4A pushing back against the
`?ared opening of the wire mesh stent, thus closing the
`valve. The sliding obturator will therefore allow blood
`?ow in only one direction.
`In another embodiment of the percutaneous cardiac
`valve which may be used in this invention, a ball design
`is employed. In this design as shown in FIG. 5, the distal
`end of the wire mesh stent possesses two curved wires
`24 and 26 that extend beyond the stent into the ventri
`cle, forming a cage structure that will house a small
`silicone rubber sphere or ball 28. The silicone sphere
`will have a hydrophilic coating to diminish throm
`bogenicity. The silicone sphere will be introduced de
`?ated (not shown) attached to the end of a smaller
`catheter, such as, for example one sized 8F, through the
`same delivery sheath used for the placement of the stent
`with the distal cage. Once in position within the cage,
`the sphere will be in?ated with a polymer mixture that
`will have a rapid set-up time hardening within minutes.
`Silicone materials are well known to be suitable for this
`purpose. After the sphere has been in?ated as shown in
`FIG. 6, it will be separated from its delivery catheter
`and will remain inflated due to a self-sealing valve 30 at
`its attachment point with the delivery catheter. During
`diastole or the ventricular ?lling stage, the sphere will
`be carried forward by blood ?ow, thus opening the
`valve. The cage will act to restrict the motion of the
`sphere, preventing it from being lost within the ventri
`cle. During systole, the sphere will be forced backwards
`due to markedly increased intraventricular pressure,
`thus closing the valve. The design of the ball version of
`the percutaneous cardiac valve useful in this invention
`is similar to the Starr-Edwards cardiac valve which also
`uses a ball-valve mechanism to allow only one-way
`?ow through the valve.
`Uniquely in this invention, the stent and valves of this
`invention are made from a shaped memory nitinol alloy
`with a transition temperature in the range of about 90°
`to about 96° F. and preferably about 95° F. Those
`
`35
`
`45
`
`65
`
`Edwards Exhibit 1038, pg. 6
`
`

`
`5,332,402 _
`
`8
`cool temperature suf?cient to maintain the cardiac
`valve in said compressed form and which is capa
`ble of passing through heart within which the car
`diac valve is to be implanted;
`manipulating the positioning device within the heart
`so as to position the cardiac valve at a desired
`location with the heart;
`ceasing maintaining cool temperature to effect expan
`sion of the cardiac valve to a desired shape wherein
`the valve engages the walls of the heart;
`disengaging the positioning device from the ex
`panded cardiac valve; and
`removing the positioning device to leave the cardiac
`valve implanted within the heart.
`2. The method of claim 1 wherein the cardiac valve
`comprises a stent and sliding obturator.
`3. The method of claim 1 wherein the cardiac valve
`comprises stent and caged ball.
`4. The method of claim 1 wherein the cardiac valve
`expands at about body temperature.
`5. The method of claim 1 wherein the cardiac valve is
`a mitral valve.
`6. A cardiac heart valve comprising a stent and slid
`ing obturator formed of a shaped memory alloy which
`has a transition temperature of from about 90° to about
`96° F.
`7. The cardiac heart valve of claim 6 wherein the
`transition temperature is about 95° F.
`8. A mitral cardiac heart valve comprising a stent and
`ball and cage formed of a shaped memory alloy which
`has a transition temperature of from about 90° to about
`96° F.
`
`* * * * *
`
`5
`
`7
`skilled in the art will appreciate that the transition tem
`peratures of the nitinol family of alloys can be manipu
`lated over a wide range by altering the nickel-titanium
`ratio, by adding small amounts of other elements, and
`by varying deformation and annealing processes.
`Therefore, no further description of the composition of
`the shape memory nitinol alloy is necessary.
`In this invention, the cool and cold temperatures used
`are those temperatures below about 75° F. In particular,
`iced-cold temperatures are generally below about 32° F.
`and those skilled in the art will appreciate that the com
`pression temperatures of the nitinol family of alloys can
`be manipulated over a wide range by altering the nickel
`titanium ratio, by adding small amounts of other ele
`ments, and by varying deformation and annealing pro
`cesses. Therefore, no further description of the compo
`sition of the shape memory nitinol alloy is necessary.
`While this invention has been described in its pre
`ferred form with a certain degree of particularity, it is
`understood that the present disclosure of the preferred
`forms and embodiments have been made only by way of
`example and that numerous changes in the details of
`construction and the combinations and arrangement of
`parts may be resorted to without departing from the
`spirit and the scope of the invention as claimed.
`What is claimed is:
`1. A method of implanting an expansible cardiac
`valve within a heart wherein the expansible cardiac _
`valve is comprised of a recovery metal having memory
`and which is capable of expanding to a desired shape
`comprising:
`releasably coupling a cardiac valve in a compressed
`form to a positioning device while maintaining a
`
`25
`
`35
`
`45
`
`55
`
`60
`
`65
`
`Edwards Exhibit 1038, pg. 7