Patent Description:
Referring first to <FIG>, the human heart is generally separated into four pumping chambers, which pump blood through the body. Each chamber is provided with its own one-way exit valve. The left atrium receives oxygenated blood from the lungs and advances the oxygenated blood to the left ventricle through the mitral (or bicuspid) valve. The left ventricle collects the oxygenated blood from the left atrium and pushes it through the aortic valve to the aorta, where the oxygenated blood is then distributed to the rest of the body. Deoxygenated blood from the body is then collected at the right atrium and advanced to the right ventricle through the tricuspid valve. The right ventricle then advances the deoxygenated blood through the pulmonary valve and the pulmonary arteries to the lungs to again supply the blood with oxygen.

Each of the valves associated with the chambers of the heart are one-way valves that have leaflets to control the directional flow of the blood through the heart, and to prevent backflow of the blood into other chambers or blood vessels that are upstream of the particular chamber. For example, as described above, the mitral valve controls the flow of oxygenated blood from the left atrium to the left ventricle, while preventing blood flow back into the left atrium. The valves are each supported by an annulus having a dense fibrous ring attached either directly or indirectly to the atrial or ventricular muscle fibers. When a valve become diseased or damaged, leakage or regurgitation may occur, where some of the blood travels back upstream through the diseased or damaged valve, and the efficiency and/or general functionality of the heart may be compromised.

Various surgical techniques can be performed to repair or replace a diseased or damaged valve. In some valve replacement procedures, the leaflets of the diseased or damaged native valve are first removed to prepare the valve annulus for receiving the prosthetic replacement valve. <FIG> shows an example of one type of popular prosthetic replacement valve <NUM> that is a tissue-type bioprosthetic valve generally constructed with natural-tissue valve leaflets <NUM>, made for example, from porcine tissue or bovine pericardium, or from synthetic leaflets, that are mounted on a surrounding valve stent structure <NUM>. The shape and structure of the leaflets <NUM> is supported by a number of commissure posts <NUM> positioned circumferentially around the valve stent structure <NUM>. In these valves, a biocompatible cloth-covered suture or sewing ring <NUM> can also be provided on an inflow end of the stent structure <NUM> of the valve <NUM>, to facilitate easier attachment to the native valve annulus. Such prosthetic valves function much like natural human heart valves, where the leaflets coapt against one another to effect the one-way flow of blood.

When implanting a tissue type prosthetic valve as described above at a native valve annulus, a number of sutures may be involved in the attachment process, many of which may be pre-installed for providing a track on which the valve is advanced to and properly positioned at the implant site. Additional sutures may also be applied between the prosthetic valve and the heart walls after proper placement, to securely attach or hold the valve implant in place. Meanwhile, in some cases, the prosthetic valves are implanted through small access channels using one of various minimally invasive surgical procedures, where visibility at the implant site may be impeded or obstructed. In addition, depending on the direction of implantation, for example, with some mitral valve replacement procedures, commissure posts of the stent or frame, or other portions, of the prosthetic valve may be pointed distally and advanced on a blind side of the valve, thereby obstructing visibility of the posts or other portions during advancement and implantation.

Each of the above factors may lead to tangling of the sutures with the valve prosthesis, most commonly with the commissure posts of the frame, since the commissure posts provide a protrusion on which the sutures can easily loop around and tangle. This type of entanglement of sutures with prosthetic valves is referred to as "suture looping," which specifically refers to instances where a suture is inadvertently wrapped around one or more of the commissure post tips, where it can then migrate towards and damage the leaflets or interfere with proper leaflet coaptation or other valve operation when the sutures are tightened or secured, resulting in improper valve operation. In some cases, such tangling may not be apparent to the practitioner at the time of implantation, and will only be revealed some time later when valve operation is observed to be improper or other complications arise in the patient, in which case, it may be necessary to initiate another procedure to repair or replace the prosthetic valve.

In addition, many existing bioprosthetic valves are not amenable to implantation through a minimal-size incision, such as in thoracotomy procedures. Such procedures can require a surgical valve and its holder to fit through incisions of approximately <NUM>-<NUM> in its narrowest direction.

Attempts have been made to resolve the issue of suture looping, some of which involve holders that hold the prosthetic valves during delivery of the valves to the native valve annulus. In one example, a holder has a mechanism that urges the commissure posts of the prosthetic valve radially inwardly during delivery, such that the ends of the commissure posts are pointed inwards, to reduce the possibility of sutures catching against or looping around the commissure posts. After the valve prosthesis is delivered to the implant site, the holder is removed thereby releasing and expanding the commissure posts to their original positions. However, such holders may not be amenable to minimally invasive surgical techniques as the holder and valve combination may have a high or large profile, for example with the entire holder system positioned outside the valve, or the holder may not pull in the commissures enough to reduce the valve profile.

Meanwhile, Edwards Lifesciences has developed a valve holder system that can be used in mitral valve replacement procedures to protect the valve from suture looping during valve implantation. The system includes monofilament sutures that attach to both the holder and the commissures of the prosthetic valve, so that the sutures run over the outflow end of the valve between the ends of the commissures. When the holder is actuated, a central post extends distally through the prosthetic valve between the leaflets and pushes against the sutures that run across the middle of the valve between the commissures, pushing the sutures distally and causing an angled tent-like or "umbrella" effect on the sutures. The pressure on the sutures deflects the commissures slightly inwardly, while also forming angled surfaces or tracks with the sutures that slope outwardly from the central post to the commissure posts. These angled surfaces deflect any other sutures that might otherwise be looped over a commissure or leaflet away from the prosthetic valve. However, this system may not be very amenable to a minimally invasive surgical approach. The system does not pull in the commissures enough to reduce the valve profile, and the central post of the holder adds to the overall height of the valve once deployed, hindering minimally invasive surgical procedures.

In addition to the above, many of the newer holder designs also incorporate many additional parts that must be assembled by the practitioner or other end user, which may also lead to additional complications. Some holders incorporate various mechanisms and line connections, such that a number of additional steps must be taken by the practitioner to operate the holders correctly. Many of these holders have proven to be too complicated and/or prone to user error. For example, some holders may allow valves to be implanted without requiring that its mechanism be activated or deployed prior to delivery, for example, holders that allow delivery without deploying its mechanism to urge the commissure posts radially inward prior to insertion. Consequently, when practitioners use these holders improperly, suture looping still commonly occurs, while the implant process may also be further complicated by issues arising from user error. Further, some holders may require the practitioner to manually adjust the tightening of the holder to the prosthetic valves. Tightening too little can make the holder ineffective to prevent suture looping, while over-tightening can risk breaking one or more sutures of the system or damaging the valve. <CIT> discloses a valve holder for facilitating implantation of a prosthetic heart valve by preconstricting and shielding valve commissure posts. The valve holder has solid legs that directly contact and constrict and hold the commissure posts without the use of sutures in tension that might creep over the time in storage. The holder has a base in contact with the inflow end and a shaft portion that projects through the valve leaflets and cooperates with movable legs on the outflow end of the valve in contact with the commissure posts. <CIT> and <CIT> disclose other valve holders for facilitating implantation of a prosthetic heart valve by preconstricting and shielding valve commissure posts.

Accordingly, a new replacement valve holder includes built-in mistake-proofing to ensure the anti-suture looping mechanism is engaged. In some embodiments, the new replacement valve holder can be designed to enable surgeons to implant the valve through minimal incisions, such as in thoracotomy procedures.

In one example, to fit through a minimal size incision, such as a <NUM>-<NUM> incision, a valve and holder combination can be collapsible in at least one direction. However, such holders and valves may not include a mechanism to actively collapse the valve into the reduced size configuration for delivery. Accordingly, an introducer according to other embodiments of the invention can be used with collapsible surgical valves and/or holders to introduce them into narrow surgical incisions, such as thoracotomies.

Features of the present disclosure provide for new holder systems and methods of using the holder systems, which reduce or eliminate the occurrence of suture looping or other damage to the prosthetic valves during implantation, for example, for mitral valve replacement using minimally invasive procedures or other procedures. Operation of the holders is also simplified, whereby the valves are prevented from being implanted prior to deployment of the holders, for example, via a holder that automatically activates upon connection of a handle to the holder, thereby reducing or eliminating mistakes caused by user error. According to embodiments, the system cannot be implanted until the handle is attached and activates the system. The holders also provide for integrated alignment features or other safety features, such that over-deployment or under-deployment of the holders is prevented.

According to embodiments of the invention, holders for prosthetic valve delivery reduce or eliminate occurrences of suture looping and/or other damage to the valves when the valves are implanted, while the mechanisms for deploying these features are integrated into the holders in a way that reduces or eliminates mistakes in use and deployment.

According to embodiments of the invention, the prosthetic valve includes a wireform and stiffener band made of materials that exhibit superelastic properties, such as nitinol, so that the stiffener band can be ovalized to a high degree for delivery through a small surgical incision. In addition, the holder according to some embodiments includes flexible arms to allow the valve holder to deform along with the prosthetic valve when compressed for insertion through a small incision, such as in minimally invasive procedures.

In the embodiments of the invention, a mitral valve holder is provided that uses a linearly movable piston to pull in the commissures of the valve towards the center of the valve, thereby eliminating the risk of suture looping. The holder has mistake-proofing features that prevent the physician from implanting the valve without engaging the system. For example, attaching the handle to the valve holder causes the piston to translate and thereby activate the system. The valve holder is prevented from being implanted before the handle is attached to the system. In some embodiments, by collapsing or deforming the profile of the valve and the valve holder, the holder system can allow implantation of the valve through a small or minimal incision. According to some embodiments, an introducer is provided to aid in implanting replacement valves through a minimal size incision, for example, by aiding in collapsing or otherwise reducing the profile of the valve and/or valve holder. The introducer can be used, for example, with mitral and/or aortic surgical valves. In some embodiments, such an introducer can be relatively short and only long enough to pass the valve past a patient's ribs. In other embodiments, the introducer can be relatively long and, for example, act as an atrial retractor, forming a channel all the way to the implant site in the case of a mitral valve.

Further features and advantages of the invention will become apparent from the description of embodiments using the accompanying drawings. In the drawings:.

Disclosed herein are various tools, such as valve holders and introducers, for assisting in the delivery and implantation of prosthetic heart valves, such as mitral heart valves, at an implant site. Disclosed are also methods for preparing the prosthetic heart valves for such procedures. Also disclosed are valves having a wireform and stiffener band made of materials that exhibit superelastic properties, such as nitinol, so that the stiffener band can be ovalized to a high degree for delivery through a small surgical incision. Embodiments of the valve holders and valves reduce occurrences of various complications that may arise during implantation, while remaining simple for end users to use. By providing these improved valve holders and valves, damage to the prosthetic valves during surgical procedures can be reduced, and additional costs for extended or additional procedures and/or replacement valves can be avoided.

The valve holders disclosed herein are particularly useful for avoiding suture looping and other valve damage during advancement of the prosthetic valves to the implant sites, as well as during final suturing of the valves at the native valve annulus. In many existing mitral valve replacement procedures, commissure posts of the prosthetic valve point distally away from practitioners, and in the direction of valve advancement and may be more prone to suture looping or other entangling. For such procedures, valve holders according to embodiments of the invention can urge the commissure posts radially inwards toward a center of the valve to reduce or eliminate suture looping. The presented embodiments can also include features that prevent valve implantation until the valve holders are in the activated or deployed positions. The holders can also include alignment features that prevent over-deployment or under-deployment. In this fashion, the holders provide ease of use while minimizing user errors.

The disclosed mitral valve holder and handle system is specifically designed to address shortcomings in previous valve holders. The disclosed system prevents clinicians from forgetting or neglecting to deploy the system by means of a handle that deploys the valve holder upon attachment of the handle. Specifically, the disclosed valve holder system deploys automatically when the clinician attaches the handle to the valve holder, thereby preventing implantation before the system is deployed. The valve holder is unable to be implanted until the handle is attached, thereby enhancing safety of surgical procedures. In addition, the disclosed system becomes fully deployed upon attaching the handle, thereby preventing under-deployment or over-deployment of the system and damage to the valve or the sutures. As such, attachment of the handle to the valve holder provides mistake-proof deployment of the system as an automatically-deploying suture looping protection mechanism. The mechanism deploys when the handle is attached to it, thereby eliminating extra steps of deployment of the valve and adding a degree of mistake-proofing. Further, the disclosed valve holder allows the valve to be compressed to fit through a minimal size incision such as a thoracotomy. The prosthetic valve, for example, a prosthetic valve that is structurally similar to the prosthetic valve shown in <FIG>, can be made of a nitinol wireform and nitinol stiffener band exhibiting a large amounts of flexibility to temporarily compress or deform the valve to fit through a minimal size incision.

<FIG> show views of a valve holder <NUM>. <FIG> shows an exploded perspective view of the valve holder <NUM>, <FIG> shows a perspective view of the valve holder <NUM> in an assembled state, <FIG> shows a cross-sectional view of the valve holder <NUM> in the assembled state, and <FIG> shows a perspective view of the valve holder <NUM> in the assembled state with an attached prosthetic valve.

The valve holder <NUM> includes a body <NUM>, an insert <NUM>, a piston <NUM>, a shaft <NUM>, and a suture mount <NUM>. As described in more detail below, a prosthetic heart valve can be attached to the body <NUM>. The insert <NUM> is positioned in a bore of the body <NUM> and connectable to a handle <NUM> to deploy or activate the valve holder <NUM> to adjust the prosthetic valve to a delivery or implantation position. The piston <NUM> is attached to the body <NUM> and to the insert <NUM>. The piston <NUM> is movable from a first configuration where the valve holder <NUM> is un-deployed for connecting the prosthetic valve to the valve holder <NUM>, to a second configuration where the valve holder <NUM> is deployed for implantation of the prosthetic valve in a heart of a human body. The shaft <NUM> is for connecting the piston <NUM> to the suture mount <NUM>. The suture mount <NUM> is for routing sutures used to connect the valve holder <NUM> to the prosthetic valve.

The body <NUM> of the valve holder <NUM> is shown in further detail in <FIG> and <FIG>. The body <NUM> includes a generally cylindrically-shaped central hub <NUM> having a central axis, and a plurality of arms <NUM> extending from the central hub <NUM>. The central hub <NUM> extends from a first proximal end 102a of the body <NUM> to a second distal end 102b of the body <NUM>. The arms <NUM> serve as routing points for connecting commissure posts of the prosthetic valve to the valve holder <NUM> via sutures or other flexible material. The arms <NUM> are flexible and hinged relative to the central hub <NUM>, and may be utilized as flexible living hinges during implantation. The flexible arms <NUM> allow the valve holder <NUM> to deform along with the prosthetic valve when compressed for insertion through a small incision, such as in minimally invasive procedures. In particular, the arms <NUM> are able to flex inward towards the hub <NUM>, and laterally in some cases, to accommodate an ovalization of the valve as it is passed through a small surgical opening. Thereby, the valve and valve holder are able to pass through an opening about the size of a typical thoracotomy procedure without rib spreading, which may be approximately <NUM> in the narrowest direction. The flexible arms <NUM> may be resilient such that the flexible arms <NUM> may be deformed to fit through a small incision, and return to their original shape when the valve and valve holder <NUM> pass through the small incision.

In the embodiment shown, the body <NUM> includes three arms <NUM>, but can include more or fewer arms <NUM> in other embodiments depending on the prosthetic valve the valve holder <NUM> is intended to hold. The number of arms <NUM> generally corresponds to the number of commissure posts on the prosthetic valve. When three arms <NUM> are included in the body <NUM>, the arms <NUM> can be positioned around the body <NUM> at approximately <NUM> degrees relative to each other.

Each of the arms <NUM> includes one or more through holes or bores <NUM> for routing sutures connecting the valve holder <NUM> to the prosthetic valve. As will be further described below, the sutures are used to deploy or activate the valve holder <NUM> and place the valve in a delivery position where the commissure posts are urged radially inwards toward a center of the valve to reduce or eliminate suture looping. The through holes <NUM> extend transversely through the arms <NUM>. The through holes <NUM> route the sutures across the top of the arms <NUM> (as illustrated) to a region below the arms <NUM> where the sutures can connect to tips of the commissure posts, for example, by passing the sutures over and/or through other portions of the valve. Multiple through holes <NUM> can be provided. Through holes 118a located near free ends of the arms <NUM> are used to route and position the sutures for connection to the commissure posts. Through holes 118b closer to the central hub <NUM> can be used to fasten or tie off an end of the sutures to the body <NUM>, and to facilitate easier release of the valve from the valve holder <NUM>. In some embodiments, through holes 118c on the central hub <NUM> may further be provided to facilitate easier release of the valve from the valve holder <NUM>.

Referring to <FIG>, the valve holder <NUM> may be connected to the prosthetic valve via sutures as follows. An end of the suture is fastened to the arms <NUM>, for example, via a knot, and routed into the through holes 118a of the arms <NUM> near the free ends of the arms <NUM>. The ends of the arms <NUM> are attached to the sewing ring of the valve via the suture, such that the flexible arms <NUM> can serve as living hinge areas to be compressed for implantation in minimally invasive surgical procedures. As shown in <FIG>, the ends of the arms <NUM> may be respectively attached to the sewing ring of the valve at a single location. This attachment method, unlike previous valve holders which require two attachment points at each location, allows the arms <NUM> to pivot on the sewing ring when the system is deformed. The sutures are routed through the sewing ring of the valve, connected to the commissure posts of the valve, and routed through channels <NUM> of the suture mount <NUM>. The sutures are then routed back through the valve and into through holes 118b, 118c located on or near the central hub <NUM>. In some embodiments, a different number of through holes <NUM> can be provided for each suture, and in some embodiments, only one through hole <NUM> is provided for each suture, located on each respective arm <NUM>.

An individual suture may be routed through both through holes 118b and 118c to provide a quick and easy method for removal of the valve from the valve holder <NUM> (see <FIG>). At the first end 102a of the body <NUM>, an upper surface of the central hub <NUM> includes a recess or slot <NUM> between the through holes 118b and 118c. The sutures extend across the recesses <NUM> such that there is a clearance underneath the sutures in the region of the recesses <NUM> to provide space for cutting the sutures. Cutting the sutures at the region of the recess <NUM> will release the valve from the valve holder <NUM>. For example, when three arms <NUM> and three sutures are provided, the three sutures can be cut in the region of the recesses <NUM> to release the valve. If the valve is in the delivery position, cutting the sutures will also allow the commissures to spring back to a normal or unbiased geometry by releasing the commissure posts.

In use, the valve is designed to be placed over and/or around the second end 102b of the body <NUM> such that the body <NUM> is inserted into the valve. At the first end 102a, a bore <NUM> is provided in the central hub <NUM> for receiving the insert <NUM> therein. The bore <NUM> extends from the first end 102a and towards the second end 102b. Two through holes 118d are provided at the first end 102a for connecting the insert <NUM> to the central hub <NUM> via a single suture. A single suture connection to the insert <NUM> allows for quick and easy removal of the insert <NUM> from the body <NUM> by cutting the suture (see <FIG>). At the second end 102b, an opening <NUM> is provided to allow a portion of the piston <NUM> to extend therethrough. An outer surface of the central hub <NUM> at the second end 102b may be tapered (e.g., may have a width or diameter that increases in a direction towards the first end 102a) to facilitate mounting of the valve or passing of the central hub <NUM> through the valve. The second end 102b additionally includes engagement portions <NUM> for connection to locks <NUM> of the piston <NUM>. Each of the engagement portions <NUM> of the body <NUM> includes a channel 126a and a notch or protrusion 126b to facilitate engagement of the locks <NUM> of the piston <NUM>, as further described below. The number of engagement portions <NUM> matches the number of locks <NUM> of the piston <NUM>. In the embodiments shown, two engagement portions <NUM> and two locks <NUM> are provided. However, it should be appreciated that the number of engagement portions <NUM> and locks <NUM> may be varied in other embodiments.

The insert <NUM> of the valve holder <NUM> is shown in further detail in <FIG> and <FIG>. The insert <NUM> has a generally cylindrical shape with a flange <NUM> at a first proximal end 104a. The flange <NUM> includes two through holes <NUM> for communicating with the through holes 118d of the body <NUM> to connect the insert <NUM> to the body <NUM> via a single suture. The flange <NUM> may cover the other sutures discussed above that hold the body <NUM> to the valve, thereby preventing the holder <NUM> from being inadvertently or unintentionally released from the valve when, for example, releasing the insert <NUM> and the handle <NUM> from the body <NUM>.

The insert <NUM> further includes a central opening <NUM> that extends through the insert <NUM> from the first proximal end 104a to a second distal end 104b, and a central axis. The insert <NUM> is configured to be received in the bore <NUM> of the body <NUM> such that the central axis of the insert <NUM> is aligned with (e.g., collinear with) the central axis of the body <NUM>. The second end 104b of the insert <NUM> is designed to receive the piston <NUM> therein. The second end 104b includes slots or channels <NUM> extending towards the first end 104a to provide clearance for the locks <NUM> of the piston <NUM>. The number of slots <NUM> matches the number of locks <NUM> of the piston <NUM>. The insert <NUM> additionally includes an unthreaded lead-in portion 136a at the first end 104a followed by a threaded portion 136b for connection to the handle <NUM>. The threaded portion 136b extends towards the second end 104b. The unthreaded portion 136a acts as a guide when inserting the handle <NUM> into the insert <NUM> to ensure proper alignment between the two parts before threading begins. This will greatly reduce the chances of cross-threading between the parts and generating undesirable particles. In addition, an outer surface of the insert <NUM> may include a key <NUM> for mating with a keyway <NUM> of the body <NUM>. The key <NUM> and keyway <NUM> enable proper alignment of the insert <NUM> relative to the body <NUM>.

The piston <NUM> of the valve holder <NUM> is shown in further detail in <FIG> and <FIG>. The piston <NUM> has a generally cylindrical shape from a first proximal end 106a to a second distal end 106b. The second end 106b includes a bore <NUM> for receiving a portion of the shaft <NUM> therein. An outer surface of the piston <NUM> at the second end 106b may be tapered (e.g., may have a width or diameter that increases in a direction towards the first end 106a). Meanwhile, the outer surface of the piston <NUM> includes the locks <NUM> for connection to the engagement portions <NUM> of the body <NUM>. The locks <NUM> are provided on flexible arms <NUM> of the piston <NUM> that extend in a direction towards the first end 106a. In some embodiments, the locks <NUM> may be shaped as outwardly facing protrusions configured to be received in the channels 126a of the body <NUM>. In some embodiments, the locks <NUM> of the piston <NUM> may be shaped as openings configured to receive inwardly facing protrusions of the body <NUM>. The flexible arms <NUM> are spaced apart from the remainder of the piston <NUM> by gaps <NUM> on either side of the flexible arms <NUM> such that the flexible arms <NUM> are movable (e.g., bendable) relative to the other parts of the piston <NUM>. The flexible arms <NUM> may be bent inwards relative to the other parts of the piston <NUM> and towards or into a cavity <NUM> of the piston <NUM>. The flexible arms <NUM> may be resilient such that the arms <NUM> can be deflected inwards and then released, causing the arms <NUM> to spring back outwards to a relaxed shape when no longer deflected. In addition, the first end 106a of the piston <NUM> includes a bore <NUM> for connection to a tip portion <NUM> of the handle <NUM>. The piston <NUM> also includes a central post <NUM> that acts as a stop for the tip portion <NUM> of the handle <NUM>.

The suture mount <NUM> is used for suture routing. The suture mount <NUM> has a plurality of channels <NUM> extending from a first end 110a of the suture mount to a second end 110b of the suture mount (see <FIG> and <FIG>). The number of channels <NUM> generally corresponds to the number of commissure posts on the prosthetic valve. As described above, each channel <NUM> is used for routing a suture between one of the commissure posts of the valve and the central hub <NUM> of the body <NUM>. As described in further detail below, the suture mount <NUM> may be moved distally (e.g., in a direction away from the first end 102a of the body <NUM>) to urge the commissure posts downward and radially inwards toward a center of the prosthetic valve. In addition, the first end 110a of the suture mount <NUM> has a bore <NUM> to connect to the shaft <NUM>. In some embodiments, the suture mount <NUM> may have a generally spherical shape, but is not limited thereto or thereby.

The shaft <NUM> is used to connect the piston <NUM> to the suture mount <NUM>. The shaft <NUM> may be connected to the bore <NUM> of the suture mount <NUM> via a press fit, interference fit, through fasteners such as a set screw, and/or via an adhesive or the like. Similarly, the shaft <NUM> may be connected to the bore <NUM> of the piston <NUM> via a press fit, interference fit, through fasteners such as a set screw, and/or via an adhesive or the like. It should be appreciate that the shaft <NUM> may be connected to the piston <NUM> via a different type of connection than is used to connect the shaft <NUM> to the suture mount <NUM>. For example, the shaft <NUM> may be connected to the piston <NUM> via an adhesive, and the shaft <NUM> may be connected to the suture mount <NUM> via a set screw.

The valve holder <NUM> may be assembled according to some embodiments as follows. The piston <NUM> may be inserted into the body <NUM> at the first end 102a, and moved distally such that the piston <NUM> extends out of the second end 102b of the body <NUM>. In some embodiments, the suture mount <NUM> may have a larger diameter or width than the opening <NUM> of the second end 102b of the body <NUM>, such that the suture mount <NUM> cannot be attached to the valve holder <NUM> until after the piston <NUM> is inserted into the body <NUM>. In some embodiments, the piston <NUM> may be preassembled with the shaft <NUM> such that the piston <NUM> and the shaft <NUM> are inserted together into the body <NUM>. In other embodiments, the shaft <NUM> may be connected to the piston <NUM> after the piston <NUM> is inserted into the body <NUM>. The opening <NUM> of the body <NUM> is larger than the maximum diameter or width of the shaft <NUM> such that the shaft <NUM> may be inserted therethrough. In some embodiments, the suture mount <NUM> may have a smaller maximum diameter or width than the opening <NUM> of the body <NUM>, such that the piston <NUM>, the shaft <NUM>, and the suture mount <NUM> may be preassembled, and all three components may be inserted together into the body <NUM>. After the piston <NUM> is inserted into body <NUM> and the shaft <NUM> and suture mount <NUM> are connected, the valve may be connected to the body <NUM> and the suture mount <NUM> via sutures as described above. Subsequently, the insert <NUM> may be inserted into the body <NUM> and connected to the body <NUM> using a single suture as described above. The insert <NUM> is inserted into the body <NUM> such that the key <NUM> of the insert <NUM> is aligned with the keyway <NUM> of the body <NUM>, and such that the slots <NUM> of the insert <NUM> are aligned with the locks <NUM> of the piston <NUM>. In some embodiments, the slots <NUM> of the insert <NUM> permit translation of the piston <NUM> relative to the insert <NUM>, but restrict or prevent rotation of the piston <NUM> relative to the insert <NUM>. Further, in some embodiments, the insert <NUM> may be inserted into the body <NUM> before connecting the prosthetic valve to the valve holder <NUM>.

Referring to <FIG> and <FIG>, the valve holder <NUM> may be moved between a first configuration for connecting the prosthetic valve to the valve holder <NUM>, and a second configuration where the prosthetic valve is in a collapsed or delivery position for implantation of the valve.

In the first configuration as shown in <FIG>, the piston <NUM> is recessed relative to the body <NUM> such that the locks <NUM> of the piston <NUM> are adjacent or near end portions 134a of the slots <NUM> of the insert <NUM>, for connection to the handle <NUM> having a tip portion <NUM> and a threaded portion <NUM>. In the first configuration, the handle <NUM> can be inserted into the insert <NUM> and advanced distally until the tip portion <NUM> contacts or is positioned in the bore <NUM> of the piston <NUM> and the threaded portion <NUM> is adjacent or positioned in the unthreaded lead-in portion 136a of the insert <NUM>. In other words, the threaded portion <NUM> of the handle <NUM> will first reach the unthreaded lead-in portion 136a of the insert <NUM> before reaching the threaded portion 136b of the insert <NUM>. The unthreaded portion 136a helps prevent potential cross threading and particle generation by ensuring axial alignment of the handle <NUM> and the threaded portion 136b of the insert <NUM>. In some embodiments, the threaded portion <NUM> of the handle <NUM> may have a thread size of, for example, #<NUM>-<NUM> or M5.

When the valve holder is in the first configuration, the handle <NUM> can be screwed into the valve holder <NUM> to actuate the anti-suture-lopping mechanism. In particular, the handle <NUM> can be screwed in such that the threaded portion <NUM> of the handle <NUM> engages the threaded portion 136b of the insert <NUM>. In so doing, the tip portion <NUM> of the handle <NUM> will axially press against the piston <NUM> to cause the piston <NUM> to move distally away from the first end 102a of the body <NUM>. When the sutures are connected to the suture mount <NUM>, the axial movement of the piston <NUM> will create tension in the suture lines and cause the sutures to be pulled in the direction of the moving piston <NUM>. Because the sutures are connected to the commissure posts of the prosthetic valve, this distal pulling force activates or deploys the valve holder <NUM> to adjust the prosthetic value to a collapsed or delivery position by transferring the force onto the commissure posts of the prosthetic valve. The commissure posts are thereby radially urged inwards toward a center of the prosthetic valve.

The handle <NUM> can continue to be screwed into the valve holder <NUM> to reach a second configuration in <FIG>, where the locks <NUM> of the piston <NUM> engage the engagement portions <NUM> of the body <NUM>. Thereby, the locks <NUM> of the piston <NUM> will be pressed against the notches 126b of the engagement portions <NUM> to move into engagement with the channels 126a. In some embodiments where the locks <NUM> of the piston <NUM> include outwardly extending protrusions, the locks <NUM> will deflect inwards upon contact with the notches 126b, and snap into the channels 126a. The notches 126b of the body <NUM> may have a tapered shape widening towards the first end 102b to facilitate deflection of the locks <NUM> of the piston <NUM>. In the second configuration, the piston <NUM> is in a fully extended position relative to the body <NUM> such that the first end 106a of the piston <NUM> is at a maximum distance away from the first end 102a of the body <NUM>. By the engagement of the locks <NUM> of the piston <NUM> with the channels 126a of the body <NUM> in the second configuration, the piston <NUM> is prevented or hindered from moving back towards the first configuration, thereby enhancing safety of the valve holder <NUM>. That is, the engagement of the locks <NUM> and the channels 126a act as a stop to prevent or hinder relative motion between the piston <NUM> and the body <NUM> while in the second configuration. Safety of procedures using the holder <NUM> is also enhanced because the valve holder <NUM> becomes automatically deployed when connecting the handle <NUM> to the valve holder <NUM>. In addition, the locations of the piston <NUM> and the suture mount <NUM> in the second configuration are designed to place a desired amount of tension in the suture lines to radially urge the commissure posts of the valve inwards to a predetermined degree. Safety is thus further enhanced by eliminating over-tightening or under-tightening of the valve. By fully threading the handle <NUM> into the valve holder <NUM> (e.g., by bottoming out the handle <NUM>, or at least until the piston <NUM> snaps into the second configuration), the valve holder <NUM> will automatically achieve the desired amount of tightening of the valve. Meanwhile, safety is further enhanced because the valve holder <NUM> is prevented from being implanted until the handle <NUM> is connected and the valve holder <NUM> is in the second configuration. In addition, the various components of the valve holder <NUM> can be preassembled prior to use in surgical procedures, as described above.

Upon implantation to a desired location in a patient, the insert <NUM> can be disconnected and removed from the valve holder <NUM> by cutting the single suture connecting the insert <NUM> to the body <NUM> (see <FIG>). Thereby, the handle <NUM> and the insert <NUM>, which are threadably connected, can be removed together from the rest of the valve holder <NUM>. Safety of the valve holder <NUM> is enhanced because the flange <NUM> of the insert <NUM> blocks the other sutures connecting the valve to the holder <NUM> to prevent the holder <NUM> from being inadvertently or unintentionally released from the valve until the insert <NUM> is removed. Once the insert <NUM> is removed, final adjustments and implantation steps can be taken to implant the prosthetic vale at the implant site, and the valve holder <NUM> can then be disconnected and removed from the valve afterwards by cutting the sutures connecting the body <NUM> to the valve (see <FIG>).

The presented embodiments further include a prosthetic valve exhibiting a large amount of flexibility for use in minimally invasive surgical procedures. The prosthetic valve can be made of a wireform and stiffener band exhibiting large amounts of flexibility to temporarily compress or deform the valve to fit through a minimal size incision, and revert to its uncompressed state after passing through the minimal size incision. In particular, the wireform and the stiffener band can be made of a material exhibiting superelastic properties, such as nitinol. However, other materials may be used that can withstand high amounts of elastic strain and provide sufficient radial stiffness. In some embodiments, the stiffener band exhibiting superelastic properties can be ovalized to a high degree for delivery through a small surgical incision of approximately <NUM>-<NUM> by <NUM>-<NUM>, and the stiffener band can be returned to it its original circular shape, while maintaining circularity of the valve during manufacture and after implantation. Such wireforms and stiffener bands having superelastic properties can be used in replacement of existing cobalt-chrome or cobalt-chromium (CoCr) wireforms and stiffener bands, which do not permit ovalization for delivery through minimally invasive procedures.

In some embodiments, a nitinol stiffener band can have the same radial stiffness as existing prosthetic valves utilizing CoCr stiffener bands. For example, nitinol may have an initial elastic modulus that is approximately <NUM>% of the elastic modulus for CoCr alloys used in prosthetic valves. The resistance to radial force can be matched between the nitinol stiffener band and an existing CoCr band by setting the product of their area moments of inertia and their Young's moduli equal. For example, for a <NUM> valve, a CoCr stiffener band may be approximately <NUM>" or <NUM> thick. Matching the stiffness in the initial elastic range of nitinol, would result in a thickness of about <NUM>" or <NUM> for a nitinol stiffener band based on an assumed Young's modulus for nitinol that is <NUM>% of CoCr. Such a thickness for a nitinol stiffener band does not add significantly to the overall size of the valve, and permits the valve to be constructed similarly to existing prosthetic valves that utilize CoCr stiffener bands, while also being able to utilize a collapsible wireform and stiffener band that can be temporarily collapsed into an oval configuration of approximately <NUM> by <NUM>. Such a valve is able to fully recover to a circular configuration after passing through an introducer, as described above. In addition, the nitinol stiffener band can incorporate the commissure "towers" used with existing polyester bands, thereby also eliminating the need for the polyester bands and simplifying construction.

The disclosed stiffener band can be manufactured from a nitinol sheet using laser cutting, die cutting, photo etching, or other common methods of producing 2D parts from sheet material. Subsequently, the 2D parts can be formed into 3D circular parts by heat treatment methods for nitinol. The ends of the nitinol stiffener bands can be joined using laser or resistance welding, or could alternatively be temporarily joined using an elastic sleeve.

Some of the presented embodiments may also include an introducer which aids in delivering valve holders in minimally invasive surgical procedures. The introducer can be used with the collapsible surgical valves having superelastic properties described above to introduce the valves into a narrow surgical incision, such as a thoracotomy. The introducer can be used, for example, for delivering a prosthetic mitral valve to the mitral position. The introducer has a funnel-like shape for passing a collapsible heart valve from outside the body to inside the body through a narrow opening, such as the space between two ribs. In thoracotomy procedures, an incision is introduced into the chest cavity through the chest wall. In intercostal approaches, the incision is made between adjacent ribs to minimize cuts through bone, nerves, and muscle. In a typical thoracotomy procedure, the distance between the ribs, without spreading the ribs, is about <NUM> to <NUM>. Parallel to the ribs, the incision can be longer as needed, for example, approximately <NUM> or greater. Collapsible valve holders can have a small size that is particularly suited to fit in the small gap between the ribs in thoracotomy procedures.

<FIG> show views of an introducer <NUM> for introducing a valve and holder into a human body according to another embodiment. The introducer <NUM> provides a simple approach for implanting collapsible heart valves connected to flexible holders through a minimal size incision, such as in a thoracotomy procedure. Due to the small gap between human ribs, the introducer <NUM> is used as an aid for inserting valves mounted on flexible holders past the ribs and into the chest cavity during a thoracotomy or other minimally invasive procedures.

The introducer <NUM> has a hollow, funnel-like shape for receiving flexible holders with mounted valves, with a central axis of the valves pointed in a direction of insertion, for example, with an outflow end of the valve pointed or directed towards the introducer <NUM>, as shown in <FIG>. The introducer <NUM> has a first, proximal end <NUM>, and a second, distal end <NUM>. The distal end <NUM> of the introducer faces towards the incision during placement or positioning, while the proximal end <NUM> faces away from the incision and towards the operator of the holder. The proximal end <NUM> has a circular cross-sectional shape corresponding to the circular shape of the prosthetic heart valves. In use, the proximal end <NUM> is located outside of the incision. In one embodiment, the cross-section of the proximal end <NUM> is <NUM> in diameter. The distal end <NUM> has an oval cross-sectional shape corresponding to a size and shape of a surgical opening between ribs in a thoracotomy procedure. In one embodiment, the major diameter of the cross section of the distal end <NUM> is <NUM> in diameter and the minor diameter of the cross section is <NUM> to <NUM> in diameter. Between the proximal and distal ends <NUM>, <NUM>, the introducer <NUM> includes a smooth transition zone or region <NUM> connecting the ends <NUM>, <NUM>. The transition region <NUM> may have a smooth, continuous inner profile between the ends <NUM>, <NUM>, which is substantially free from corners.

The introducer <NUM> can be made very inexpensively as a disposable item that is supplied with a valve. The introducer <NUM> can be made of or include polypropylene, or any other suitable material having a low coefficient of friction. The introducer <NUM> can be a molded part. Meanwhile, the valve to be implanted can be made of a nitinol wireform band exhibiting a large degree of elasticity. In one embodiment, the valve exhibits superelastic properties.

In use, the introducer <NUM> is first introduced into an incision in the chest cavity with the distal end <NUM> positioned between two ribs. The valve, connected to a flexible holder, is inserted into the proximal end <NUM> of the introducer <NUM>, as shown in <FIG>. The valve is then pushed towards the smaller, distal end <NUM> of the introducer <NUM>, where the valve elastically deforms to squeeze through the smaller cross-sectional shape. The valve can take on the oval shape of the introducer or another generally collapsed shape as it is pushed through the introducer <NUM>, due to the superelastic properties of the valve. Once the valve clears the distal end <NUM> of the introducer <NUM>, the valve regains its undeformed shape (e.g., its circular shape). In this way, the deformation of the valve and holder <NUM> is passive, being imposed or dictated by the shape of the introducer rather than by a mechanism on the holder itself. The advantage of this configuration is that the holder can be a very inexpensive molded component.

In one embodiment, a length of the introducer <NUM> is sufficient to introduce the valve into an internal surface of the chest wall past the rib cage. In such an embodiment, a length of the introducer from the proximal end <NUM> to the distal end <NUM> may be up to <NUM> long. In other embodiments, a length of the introducer can be made longer. In one embodiment, the distal end <NUM> could be extended many more centimeters so that it would extend, for example, into the left atrium of the heart, for a mitral valve replacement, to act as an atrial retractor. Meanwhile, the proximal end <NUM> of the introducer <NUM> can remain positioned outside of the incision in the chest cavity. This would provide a tunnel from the outside of the body all the way to the site of implantation at the mitral annulus.

In alternative embodiments, the introducer <NUM> can include various additional features, for example, a slit in a wall of the introducer <NUM> can be provided to give clearance for sutures passing through a side of the introducer during surgical procedures. In addition, lighting, such as light emitting diodes ("LEDs"), can be added to the introducer, along with a power supply, such as batteries, to power the lighting. LED lighting can be inexpensively added to the introducer with a built-in battery. The lighting can be particularly useful with the extended version of the introducer. The lighting can provide excellent illumination at the site of implantation and reduce the need for additional external lighting.

For purposes of this description, certain aspects, advantages, and novel features of the embodiments of this disclosure are described herein. The disclosed methods, apparatus, and systems should not be construed as being limiting in any way. Instead, the present disclosure is directed toward all novel and nonobvious features and aspects of the various disclosed embodiments, alone and in various combinations and sub-combinations with one another. The methods, apparatus, and systems are not limited to any specific aspect or feature or combination thereof, nor do the disclosed embodiments require that any one or more specific advantages be present or problems be solved.

For example, operations described sequentially can in some cases be rearranged or performed concurrently. The actual operations that correspond to these terms can vary depending on the particular implementation and are readily discernible by one of ordinary skill in the art.

Claim 1:
A valve holder (<NUM>) for holding and implanting a prosthetic heart valve comprising a frame and a plurality of flexible leaflets, the valve holder (<NUM>) comprising:
a body (<NUM>) for holding the prosthetic heart valve, the body (<NUM>) having a proximal end (102a), a distal end, and a central axis extending between the proximal and distal ends;
an insert (<NUM>) positioned in a bore of the body (<NUM>) and being connectable to a handle (<NUM>);
a piston (<NUM>) attached to the body (<NUM>) and to the insert (<NUM>) and being configured to be positioned at least partially in the body (<NUM>), wherein when the prosthetic heart valve is held by the body (<NUM>), the piston (<NUM>) is configured to translate relative to the body (<NUM>) along the central axis to adjust the prosthetic heart valve to a delivery position;
a suture mount (<NUM>) for routing sutures connecting the valve holder (<NUM>) to the prosthetic heart valve; and
a shaft (<NUM>) for connecting the piston (<NUM>) to the suture mount (<NUM>); wherein the piston (<NUM>) is configured to move axially relative to the body (<NUM>) from a first configuration to a second configuration, such that the piston (<NUM>) is further from the proximal end (102a) of the body (<NUM>) in the second configuration than in the first configuration,
wherein the body (<NUM>) comprises a hub (<NUM>) and a plurality of arms (<NUM>), the arms (<NUM>) being flexible to allow the body (<NUM>) to deform for insertion into a small surgical opening, and
wherein the flexible arms (<NUM>) of the body (<NUM>) are configured to deform inwards in a direction towards the hub (<NUM>) such that a maximum width of the body decreases when the arms (<NUM>) are deformed,
wherein the insert (<NUM>) is between the piston (<NUM>) and the body (<NUM>), and configured to threadably engage the handle (<NUM>) to adjust the piston (<NUM>) from the first configuration to the second configuration, and
wherein in the second configuration the piston (<NUM>) and the suture mount (<NUM>) are located to place tension in the sutures to radially urge commissure posts of the prosthetic heart valve inwards.