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`
`United States Patent Application
`20110251675
`A1
`Kind Code
`October 13, 2011
`Dwork; Joshua
`Transcatheter Prosthetic Heart Valve Delivery Device With Partial Deployment and Release
`Features and Methods
`
`Abstract
`A delivery device for percutaneously deploying a stented prosthetic heart valve, including a delivery sheath,
`an inner shaft, and a spindle. The inner shaft is slidably disposed within a lumen of the delivery sheath. The
`spindle is attached to the shaft and includes a hub defining at least one longitudinal slot sized to slidably
`receive a post of the stented valve. An outer surface of the hub forms a curved proximal segment. The device
`provides a loaded state in which the delivery sheath retains the stented valve over the inner shaft and coupled
`to the spindle via the slot. In a deployed state, the distal end of the delivery sheath is withdrawn from the
`prosthesis to permit the stented valve to release from the slot, sliding along the curved outer surface of the
`hub.
`
`Inventors: Dwork; Joshua; (Santa Rosa, CA)
`Assignee: Medtronic, Inc.
`Minneapolis
`MN
`Family ID: 44761494
`Appl. No.: 12/757088
`April 9, 2010
`Filed:
`
`Current U.S. Class:
`Current CPC Class:
`Class at Publication:
`International Class:
`
`623/1.23 ; 623/1.26
`A61F 2/2418 20130101; A61F 2/2436 20130101; A61F
`2002/9665 20130101
`623/1.23 ; 623/1.26
`A61F 2/84 20060101 A61F002/84; A61F 2/82 20060101
`NORRED EXHIBIT 2281 - Page 1 A61F002/82
`Medtronic, Inc., Medtronic Vascular, Inc.,
`& Medtronic Corevalve, LLC
`v. Troy R. Norred, M.D.
`Case IPR2014-00395
`
`

`
`Claims
`
`1. A delivery device for percutaneously deploying a stented prosthetic heart valve including a stent frame to
`which a valve structure is attached, the device comprising: a delivery sheath assembly terminating at a distal
`end and defining a lumen; an inner shaft slidably disposed within the lumen; and a spindle attached to the
`shaft, the spindle including: a tubular base, a hub projecting radially outwardly relative to the base, wherein:
`the hub defines at least one longitudinal slot sized to slidably receive a corresponding post of a prosthetic
`heart valve stent frame, an outer surface of the hub forms a proximal segment and a distal segment, the
`proximal segment being curved in extension toward the distal segment; wherein the device is configured to
`provide a loaded state in which the delivery sheath assembly retains a stented prosthetic heart valve over the
`inner shaft and coupled to the spindle via the at least one slot, and a deployment state in which the distal end
`of the delivery sheath assembly is withdrawn from the prosthetic heart valve to permit the prosthetic heart
`valve to release from the at least one longitudinal slot.
`2. The delivery device of claim 1, wherein the at least one longitudinal slot includes a plurality of
`circumferentially spaced longitudinal slots formed in the hub.
`3. The delivery device of claim 2, wherein the plurality of longitudinal slots are equidistantly spaced from
`one another about a circumference of the hub.
`4. The delivery device of claim 1, wherein the proximal segment defines a proximal face of the hub and the
`distal segment defines a distal face of the hub, and further wherein the at least one longitudinal slot is open at
`the proximal and distal faces.
`5. The delivery device of claim 4, wherein the at least one longitudinal slot is defined by opposing side walls
`and a floor, and further wherein the tubular base includes a ring immediately proximal the hub, the ring
`having a surface aligned with the floor.
`6. The delivery device of claim 5, wherein the spindle further includes a flange projecting radially outwardly
`relative to the base and proximally spaced from the hub by the ring.
`7. The delivery device of claim 6, wherein an outer diameter of the flange approximates a maximum outer
`diameter of the hub.
`8. The delivery device of claim 1, wherein the outer surface defines a convex curve in longitudinal extension
`along the proximal segment.
`9. The delivery device of claim 1, wherein the outer surface, as collectively defined by the proximal and
`distal segments, approximates a semi-circle in longitudinal extension.
`10. The delivery device of claim 1, further comprising: a release sheath assembly disposed between the
`delivery sheath assembly and the spindle in the loaded state, the release sheath assembly including a release
`sheath slidably received over at least the proximal segment of the hub in the loaded state.
`11. The delivery device of claim 10, wherein the release sheath assembly is configured to proximally retract
`the release sheath relative to the hub with proximal retraction of the delivery sheath distal end from the
`release sheath.
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`12. The delivery device of claim 10, wherein the release sheath forms at least one longitudinal notch
`extending from a distal end of the release sheath, and further wherein upon final assembly in the loaded state,
`the at least one notch is longitudinally aligned with the at least one slot.
`13. The delivery device of claim 12, wherein the at least one longitudinal slot includes a plurality of
`circumferentially spaced longitudinal slots, and the at least one notch includes a plurality of circumferentially
`spaced notches, and further wherein each of the slots is longitudinally aligned with a respective one of the
`notches.
`14. The delivery device of claim 13, wherein the spindle further forms a circumferential trough between the
`hub and a flange formed proximal the hub, and further wherein the release sheath includes a plurality of
`fingers spaced from one another by the plurality of notches, and further wherein the loaded state includes the
`fingers extending across the circumferential trough.
`15. A system for repairing a defective heart valve of a patient, the system comprising: a prosthetic heart valve
`having a stent frame and a valve structure attached to the stent frame, the stent frame defining a distal region
`and a proximal region, the proximal region forming at least one post; and a delivery device comprising: a
`delivery sheath assembly terminating at a distal end and defining a lumen, an inner shaft slidably disposed
`within the lumen, a spindle attached to the inner shaft, the spindle including: a tubular base, a hub projecting
`radially outwardly relative to the base and defining at least one longitudinal slot sized to slidably receive the
`at least one post, wherein the outer surface of the hub forms a proximal segment and a distal segment, the
`proximal segment being curved in extension toward the distal segment; wherein the system is configured to
`provide a loaded condition in which the prosthetic heart valve is retained between the delivery sheath
`assembly and the inner shaft, including the at least one post slidably captured within the at least one
`longitudinal slot.
`16. The system of claim 15, wherein the at least one longitudinal slot includes a plurality of circumferentially
`spaced longitudinal slots, and further wherein the at least one post includes a plurality of posts corresponding
`with the plurality of longitudinal slots.
`17. The system of claim 15, wherein the spindle further includes a flange projecting radially outwardly
`relative to the base and proximally spaced from the hub to define a circumferential trough.
`18. The system of claim 17, wherein the at least one post includes a proximal shoulder and a distal head, the
`shoulder sized to slidably nest within the longitudinal slot and the head sized to slidably nest within the
`trough.
`19. The system of claim 18, wherein a circumferential width of the head is larger than a circumferential width
`of the shoulder.
`20. The system of claim 19, wherein the shoulder and the head collectively define a T-like shape.
`21. The system of claim 15, wherein the system is further configured to provide a deployment condition in
`which the distal end of the delivery sheath assembly is proximal the hub to permit the post to release from the
`slot, including a head of the post sliding along the curved proximal segment of the hub outer surface.
`22. The system of claim 21, wherein the stent frame is configured to radially self-expand from a compressed
`arrangement to a normal arrangement, and further wherein the loaded condition that includes the delivery
`sheath assembly compressively retaining the prosthetic heart valve in the compressed arrangement.
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`23. The system of claim 22, wherein the deployment condition includes the stent frame self-expanding to the
`normal arrangement.
`24. The system of claim 15, wherein the delivery device further includes: a release sheath assembly disposed
`between the delivery sheath assembly and the spindle in the loaded state, the release sheath assembly
`including a release sheath slidably received over at least the proximal segment of the hub in the loaded state.
`25. The system of claim 24, wherein the release sheath forms at least one longitudinal notch extending from a
`distal end of the release sheath, and further wherein upon final assembly in the loaded condition, the at least
`one notch is longitudinally aligned with the at least one slot.
`26. The system of claim 25, wherein the system is further configured to provide a deployment condition
`includes the release sheath proximally retracted from the hub and the at least one post self-pivoting through
`the at least one slot and the at least one notch.
`27. The system of claim 26, wherein the at least one post includes a distal shoulder and a proximal head, and
`further wherein the spindle forms a circumferential trough proximal the hub such that the loaded condition
`includes the shoulder disposed within the slot and the head disposed within the trough, the head being
`releasably captured within the trough by the release sheath.
`28. A method of percutaneously deploying a stented prosthetic heart valve to an implantation site of a patient,
`the method comprising: receiving a delivery device loaded with a radially expandable prosthetic heart valve
`having a stent frame to which a valve structure is attached, the delivery device including a delivery sheath
`assembly containing the prosthetic heart valve in a compressed arrangement over an inner shaft in a loaded
`state of the device, and a spindle attached to the shaft, the spindle including: a tubular base, a hub projecting
`radially outwardly relative to the base and defining at least one longitudinal slot and an outer surface forming
`a proximal segment and a distal segment, the proximal segment being curved in extension toward the distal
`segment, wherein a post of the stent frame is slidably captured within the at least one slot in the loaded state;
`delivering the prosthetic heart valve in the compressed arrangement through a bodily lumen of the patient and
`to the implantation site via the delivery device in the loaded state; proximally retracting the delivery sheath
`assembly from the prosthetic heart valve; and permitting the post to release from the at least one slot,
`including a surface of the post sliding along the curved proximal segment of the hub outer surface such that
`the prosthetic heart valve deploys from the delivery device.
`29. The method of claim 28, wherein the at least one longitudinal slot includes a plurality of circumferentially
`spaced longitudinal slots, and further wherein the at least one post includes a plurality of posts corresponding
`with the plurality of longitudinal slots.
`30. The method of claim 28, wherein the stent frame is configured to radially self-expand from a compressed
`arrangement to a normal arrangement, and further wherein the loaded state includes the delivery sheath
`assembly compressively retaining the prosthetic heart valve in the compressed arrangement.
`31. The method of claim 28, wherein the delivery device further includes: a release sheath assembly disposed
`between the delivery sheath assembly and the spindle in the loaded state, the release sheath assembly
`including a release sheath slidably received over at least the proximal segment of the hub.
`32. The method of claim 31, wherein the release sheath forms at least one longitudinal notch extending from
`a distal end of the release sheath, and further wherein permitting the post to release from the at least one slot
`includes the post pivoting relative to the spindle such that a portion of the post moves through the at least one
`slot and a corresponding one of the at least one notch.
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`Description
`
`BACKGROUND
`[0001] The present disclosure relates to systems, devices, and methods for percutaneous implantation of a
`prosthetic heart valve. More particularly, it relates to delivery systems, devices, and methods for transcatheter
`implantation of a stented prosthetic heart valve.
`[0002] Diseased or otherwise deficient heart valves can be repaired or replaced with an implanted prosthetic
`heart valve. Conventionally, heart valve replacement surgery is an open-heart procedure conducted under
`general anesthesia, during which the heart is stopped and blood flow is controlled by a heart-lung bypass
`machine. Traditional open surgery inflicts significant patient trauma and discomfort, and exposes the patient
`to a number of potential risks, such as infection, stroke, renal failure, and adverse effects associated with the
`use of the heart-lung bypass machine, for example.
`[0003] Due to the drawbacks of open-heart surgical procedures, there has been an increased interest in
`minimally invasive and percutaneous replacement of cardiac valves. With percutaneous transcatheter (or
`transluminal) techniques, a valve prosthesis is compacted for delivery in a catheter and then advanced, for
`example, through an opening in the femoral artery and through the descending aorta to the heart, where the
`prosthesis is then deployed in the annulus of the valve to be repaired (e.g., the aortic valve annulus).
`Although transcatheter techniques have attained widespread acceptance with respect to the delivery of
`conventional stents to restore vessel patency, only mixed results have been realized with percutaneous
`delivery of the more complex prosthetic heart valve.
`[0004] Various types and configurations of prosthetic heart valves are available for percutaneous valve
`replacement procedures, and continue to be refined. The actual shape and configuration of any particular
`transcatheter prosthetic heart valve is dependent to some extent upon the native shape and size of the valve
`being repaired (i.e., mitral valve, tricuspid valve, aortic valve, or pulmonary valve). In general, prosthetic
`heart valve designs attempt to replicate the functions of the valve being replaced and thus will include valve
`leaflet-like structures. With a bioprostheses construction, the replacement valve may include a valved vein
`segment that is mounted in some manner within an expandable stent frame to make a valved stent (or
`"stented prosthetic heart valve"). For many percutaneous delivery and implantation devices, the stent frame
`of the valved stent is made of a self-expanding material and construction. With these devices, the valved stent
`is crimped down to a desired size and held in that compressed arrangement within an outer delivery sheath,
`for example. Retracting the sheath from the valved stent allows the stent to self-expand to a larger diameter,
`such as when the valved stent is in a desired position within a patient. In other percutaneous implantation
`devices, the valved stent can be initially provided in an expanded or uncrimped condition, then crimped or
`compressed on a balloon portion of catheter until it is as close to the diameter of the catheter as possible. The
`so-loaded balloon catheter is slidably disposed within an outer delivery sheath. Once delivered to the
`implantation site, the balloon is inflated to deploy the prosthesis. With either of these types of percutaneous
`stented prosthetic valve delivery devices, conventional sewing of the prosthetic heart valve to the patient's
`native tissue is typically not necessary.
`[0005] It is imperative that the stented prosthetic heart valve be accurately located relative to the native
`annulus immediately prior to full deployment from the catheter as successful implantation requires the
`prosthetic heart valve intimately lodge and seal against the native annulus. If the prosthesis is incorrectly
`positioned relative to the native annulus, serious complications can result as the deployed device can leak and
`may even dislodge from the native valve implantation site. As a point of reference, this same concern does
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`not arise in the context of other vascular stents; with these procedures, if the target site is "missed," another
`stent is simply deployed to "make-up" the difference.
`[0006] To carefully and safely deploy a transcatheter prosthetic heart valve, a clinician can employ imaging
`technology to evaluate the location of the prosthesis immediately prior to deployment. In particular, one
`desirable transcatheter prosthetic heart valve implantation technique entails partially deploying a distal region
`of the prosthesis from the delivery device and then evaluating a position of the deployed distal region relative
`to the native annulus. The clinician may further desire the ability to resheath or recapture the partially
`deployed region for subsequent repositioning of the prosthesis. Regardless, in the partially deployed state, the
`proximal region of the prosthetic heart valve must remain coupled to the delivery device. While, in theory,
`retaining a partially deployed prosthetic heart valve to the delivery device is straightforward, in actual
`practice the constraints presented by the stented prosthetic heart valve render the technique exceedingly
`difficult. In particular, the delivery device must not only securely retain the prosthetic heart valve in the
`partially deployed state, but also must consistently operate to release the prosthetic heart valve when full
`deployment is desired.
`[0007] A stented heart valve is purposefully designed to rigidly resist collapsing forces once deployed so as
`to properly anchor itself in the anatomy of the heart. Thus, the delivery device component (e.g., outer
`delivery sheath) employed to retain the prosthesis in a collapsed arrangement must be capable of exerting a
`significant radial force. Conversely, the component cannot be overly rigid so as to avoid damaging the
`transcatheter heart valve during deployment. Along these same lines, the aortic arch must be traversed with
`many percutaneous heart valve replacement procedures, necessitating that the delivery device provide
`sufficient articulation attributes. To meet these constraints, the outer delivery sheath typically incorporates a
`circumferentially rigid capsule, and a coupling structure is disposed within the delivery sheath for
`temporarily capturing the stented valve. While viable, conventional delivery device designs robustly engage
`the prosthetic heart valve within the capsule; this robust engagement facilitates the partial deployment
`technique described above, but the prosthetic heart valve may undesirably catch on the inner engagement
`structure when full deployment is intended and/or numerous, complex components are required to ensure
`complete deployment. Further, clinicians prefer that a significant portion of the prosthetic heart valve be
`exposed/expanded in the partially deployed state (e.g., the inflow region and at least a portion of the outflow
`region of the prosthesis). Unfortunately, existing delivery system designs cannot consistently meet this need.
`[0008] In light of the above, a need exists for heart valve repair systems and corresponding stented
`transcatheter prosthetic heart valve delivery devices and methods that satisfy the constraints associated with
`percutaneous heart valve implantation and permit consistent partial and full deployment of the prosthesis.
`SUMMARY
`[0009] Some aspects in accordance with principles of the present disclosure relate to a delivery device for
`percutaneously deploying a stented prosthetic heart valve. The prosthetic heart valve has a stent frame to
`which a valve structure is attached. The delivery device includes a delivery sheath assembly, an inner shaft,
`and a spindle. The delivery sheath assembly terminates at a distal end and defines a lumen. The inner shaft is
`slidably disposed within the lumen. The spindle is attached to the shaft and includes a tubular base and a hub.
`The hub projects radially outwardly relative to the base, and defines at least one longitudinal slot sized to
`slidably receive a corresponding post component of the prosthetic heart valve stent frame. Further, an outer
`surface of the hub forms a proximal segment and a distal segment, with the proximal segment being curved in
`extension toward the distal segment. With this in mind, the device is configured to provide a loaded state in
`which the delivery sheath assembly retains the stented prosthetic heart valve over the inner shaft and coupled
`to the spindle via the at least one longitudinal slot. The device is further configured to provide a deployed
`state in which the distal end of the delivery sheath assembly is withdrawn from the prosthetic heart valve to
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`permit the prosthetic heart valve to release from the longitudinal slot. In some embodiments, the hub forms a
`plurality of circumferentially spaced longitudinal slots. In other embodiments, the outer surface, as
`collectively defined by proximal and distal segments, approximates a semi-circle. In yet other embodiments,
`the delivery device further includes a release sheath assembly disposed between the delivery sheath assembly
`and the spindle in the loaded state, the release sheath assembly including a release sheath slidably received
`over the proximal segment of the hub. In related embodiments, the release sheath forms a plurality of
`circumferentially spaced notches at a leading end thereof, with the notches being longitudinally aligned with
`respective ones of the slots in the hub.
`[0010] Yet other aspects in accordance with principles of the present disclosure relate to a system for
`repairing a defective heart valve of a patient. The system includes a prosthetic heart valve and a delivery
`device. The prosthetic heart valve has a stent frame and a valve structure attached to the stent frame. Further,
`the stent frame includes a proximal region forming at least one post. The delivery device includes a delivery
`sheath assembly, an inner shaft, and a spindle. The delivery sheath assembly terminates at a distal end and
`defines a lumen. The inner shaft is slidably disposed within the lumen. The spindle is attached to the inner
`shaft and includes a tubular base and a hub. The hub projects radially outwardly relative to the base and
`defines at least one longitudinal slot sized to slidably receive the post of the stent frame. Further, an outer
`surface of the hub forms a proximal segment and a distal segment, with the proximal segment being curved in
`extension toward the distal segment. With this construction, the system is configured to provide a loaded
`condition in which the prosthetic heart valve is retained between the delivery sheath assembly and the inner
`shaft, including the post being slidably captured within the longitudinal slot. In some embodiments, the post
`has a T-like shape. In other embodiments, the proximal region of the stent frame forms a plurality of the
`posts, with the hub forming a corresponding number of longitudinal slots. In other constructions, a
`deployment condition of the system includes the stent frame self-expanding from the delivery device, with
`the post sliding along the curved proximal segment of the hub outer surface.
`[0011] Yet other aspects in accordance with principles of the present disclosure relate to a method of
`percutaneously deploying a stented prosthetic heart valve to an implantation site of a patient. The method
`includes receiving a delivery device loaded with a radially expandable prosthetic heart valve having a stent
`frame to which a valve structure is attached. The delivery device includes a delivery sheath assembly
`containing the prosthetic heart valve in a compressed arrangement over an inner shaft in a loaded state of the
`device, as well as a spindle attached to the shaft. The spindle includes a tubular base and a hub projecting
`radially outwardly relative to the base and defining at least one longitudinal slot within which a post of the
`stent frame is slidably received in the loaded state. Further, an outer surface of the hub includes a curved
`proximal segment. The prosthetic heart valve is delivered in the compressed arrangement through a bodily
`lumen of the patient and to the implantation site via the delivery device in the loaded state. The delivery
`sheath assembly is proximally retracted from the prosthetic heart valve. The post is permitted to release from
`the slot, including a surface of the post sliding along the curved proximal segment of the hub's outer surface
`such that the prosthetic heart valve deploys from the delivery device. In some embodiments, the delivery
`device further includes a release sheath slidably coupled over the proximal segment of the hub in the loaded
`state to capture the post relative to the spindle, with the release sheath forming a notch that is longitudinally
`aligned with the slot and being proximally retractable with proximal retraction of the delivery sheath
`assembly. With these embodiments, the method can further include proximally retracting the release sheath
`relative to the hub, with the post self-pivoting relative to the spindle, including a portion of the post passing
`through the slot and the corresponding notch.
`BRIEF DESCRIPTION OF THE DRAWINGS
`[0012] FIG. 1A is a side view of a stented prosthetic heart valve useful with systems and methods of the
`present disclosure and in a normal, expanded arrangement;
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`[0013] FIG. 1B is a side view of the prosthetic heart valve of FIG. 1A in a compressed arrangement;
`[0014] FIG. 2 is an enlarged, perspective view of a post portion of the prosthetic heart valve of FIGS. 1A and
`1B;
`[0015] FIG. 3 is an exploded, perspective view of a stented prosthetic heart valve delivery device in
`accordance with principles of the present disclosure;
`[0016] FIG. 4A is an enlarged, perspective view of a spindle portion of the delivery device of FIG. 3;
`[0017] FIG. 4B is a side view of the spindle of FIG. 4A;
`[0018] FIG. 5 is a perspective view of a portion of a release sheath assembly component of the delivery
`device of FIG. 3;
`[0019] FIG. 6A is a simplified, side view of the release sheath assembly component of the delivery device of
`FIG. 3 and in a normal state;
`[0020] FIG. 6B is a simplified view of the release sheath assembly of FIG. 6A and in a compressed state;
`[0021] FIG. 7A is a cross-sectional view of a portion of a heart valve repair system in accordance with the
`present disclosure, including the delivery device of FIG. 3 loaded with the prosthetic heart valve of FIG. 1A;
`[0022] FIG. 7B is an enlarged, perspective view of a portion of the system of FIG. 7A;
`[0023] FIG. 8A is a perspective view of the delivery device of FIG. 3 in an initial stage of a partial
`deployment state;
`[0024] FIG. 8B is a simplified side view of the system of FIG. 7A in an initial stage of a deployment
`condition, includes the delivery device in the arrangement of FIG. 8A;
`[0025] FIG. 8C is an enlarged, perspective view of a portion of the delivery system in the partial deployment
`stage of FIG. 8A;
`[0026] FIG. 8D is an enlarged, perspective view of the system of FIG. 7A in a further stage of the partial
`deployment state;
`[0027] FIGS. 9A and 9B are simplified perspective views of the delivery device of FIG. 3 in various stages of
`transitioning to a deployment state; and
`[0028] FIGS. 10A and 10B are enlarged, perspective views of a portion of the delivery system of FIG. 7A
`and illustrating transitioning to a deployment condition in which the a prosthetic heart valve deploys from the
`delivery device.
`DETAILED DESCRIPTION
`[0029] As referred to herein, stented transcatheter prosthetic heart valves useful with and/or as part of the
`various systems, devices, and methods of the present disclosure may assume a wide variety of different
`configurations, such as a bioprosthetic heart valve having tissue leaflets or a synthetic heart valve having
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`polymeric, metallic, or tissue-engineered leaflets, and can be specifically configured for replacing any heart
`valve. Thus, the stented prosthetic heart valve useful with the systems, devices, and methods of the present
`disclosure can be generally used for replacement of a native aortic, mitral, pulmonic, or tricuspid valve, for
`use as a venous valve, or to replace a failed bioprosthesis, such as in the area of an aortic valve or mitral
`valve, for example.
`[0030] In general terms, the stented prosthetic heart valves of the present disclosure include a stent or stent
`frame maintaining a valve structure (tissue or synthetic), with the stent having a normal, expanded
`arrangement and collapsible to a compressed arrangement for loading within a delivery device. The stent is
`normally constructed to self-deploy or self-expand when released from the delivery device. For example, the
`stented prosthetic heart valve useful with the present disclosure can be a prosthetic valve sold under the trade
`name CoreValve.RTM. available from Medtronic CoreValve, LLC. Other non-limiting examples of
`transcatheter heart valve prostheses useful with systems, devices, and methods of the present disclosure are
`described in U.S. Publication Nos. 2006/0265056; 2007/0239266; and 2007/0239269, the teachings of each
`which are incorporated herein by reference. The stents or stent frames are support structures that comprise a
`number of struts or wire portions arranged relative to each other to provide a desired compressibility and
`strength to the prosthetic heart valve. In general terms, the stents or stent frames of the present disclosure are
`generally tubular support structures having an internal area in which valve structure leaflets will be secured.
`The leaflets can be formed from a variety of materials, such as autologous tissue, xenograph material, or
`synthetics as are known in the art. The leaflets may be provided as a homogenous, biological valve structure,
`such as porcine, bovine, or equine valves. Alternatively, the leaflets can be provided independent of one
`another (e.g., bovine or equine paracardial leaflets) and subsequently assembled to the support structure of
`the stent frame. In another alternative, the stent frame and leaflets can be fabricated at the same time, such as
`may be accomplished using high-strength nano-manufactured NiTi films produced at Advance BioProsthetic
`Surfaces (ABPS), for example. The stent frame support structures are generally configured to accommodate
`at least two (typically three) leaflets; however, replacement prosthetic heart valves of the types described
`herein can incorporate more or less than three leaflets.
`[0031] Some embodiments of the stent frames can be a series of wires or wire segments arranged such that
`they are capable of self-transitioning from a compressed or collapsed arrangement to the normal, radially
`expanded arrangement. In some constructions, a number of individual wires comprising the stent frame
`support structure can be formed of a metal or other material. These wires are arranged in such a way that the
`stent frame support structure allows for folding or compressing or crimping to the compressed arrangement in
`which the internal diameter is smaller than the internal diameter when in the normal, expanded arrangement.
`In the compressed arrangement, such a stent frame support structure with attached valves can be mounted
`onto a delivery device. The stent frame support structures are configured so that they can be changed to their
`normal, expanded arrangement when desired, such as by the relative movement of one or more sheaths
`relative to a length of the stent frame.
`[0032] The wires of these stent frame support structures in embodiments of the present disclosure can be
`formed from a shape memory material such as a nickel titanium alloy (e.g., Nitinol.TM.) With this material,
`the support structure is self-expandable from the compressed arrangement to the normal, expanded
`arrangement, such as by the application of heat, energy, and the like, or by the removal of external forces
`(e.g., compressive forces). This stent frame support structure can also be compressed and re-expanded
`multiple times without da