Patent Description:
This disclosure relates to stented prosthesis delivery devices and device components that have steering capabilities and methods of steering such delivery devices. <CIT> describes methods and devices for delivery of prosthetic heart valves and other prosthetics.

A human heart includes four heart valves that determine the pathway of blood flow through the heart: the mitral valve, the tricuspid valve, the aortic valve, and the pulmonary valve. The mitral and tricuspid valves are atrio-ventricular valves, which are between the atria and the ventricles, while the aortic and pulmonary valves are semilunar valves, which are in the arteries leaving the heart. Ideally, native leaflets of a heart valve move apart from each other when the valve is in an open position, and meet or "coapt" when the valve is in a closed position. Problems that may develop with valves include stenosis in which a valve does not open properly, and/or insufficiency or regurgitation in which a valve does not close properly. Stenosis and insufficiency may occur concomitantly in the same valve. The effects of valvular dysfunction vary, with regurgitation or backflow typically having relatively severe physiological consequences to the patient.

Diseased or otherwise deficient heart valves can be repaired or replaced using a variety of different types of heart valve surgeries. One conventional technique involves an open-heart surgical approach that is conducted under general anesthesia, during which the heart is stopped and blood flow is controlled by a heart-lung bypass machine.

More recently, minimally invasive approaches have been developed to facilitate catheter-based implantation of the valve prosthesis on the beating heart, intending to obviate the need for the use of classical sternotomy and cardiopulmonary bypass. In general terms, an expandable valve prosthesis is compressed about or within a catheter, inserted inside a body lumen of the patient, such as the femoral artery, and delivered to a desired location in the heart where the valve prosthesis is then deployed.

The present disclosure addresses problems and limitations relating to delivery devices, such as those of the related art.

The invention is as set forth in the appended claims. The present disclosure relates to numerous delivery devices for delivering a stented prosthesis including, but not limited to, stented prosthetic heart valves or coronary prosthesis, endoprosthesis, peripheral prosthesis, gastric devices or the like. Such delivery devices can include an optional outer sheath assembly, a shaft assembly for supporting the stented prosthesis and a handle assembly. The delivery device provides a loaded delivery state in which the stented prosthesis is loaded and compressed over the shaft assembly. The compression of the stented prosthesis can be adjusted with one or more tension members (e.g., sutures, cords, wires or filaments), which extend around the stented prosthesis and proximally to an actuation and release assembly, which can, in some embodiments, be provided in the handle assembly. The delivery device can be manipulated to adjust tension in the tension members to permit the stented prosthesis to self-expand, contract and ultimately release from the shaft assembly.

Embodiments disclosed herein further utilize tension members, routed through one or more lumens in the shaft assembly, to steer the delivery device during delivery of the stented prosthesis (e.g., to bend the shaft assembly through the aortic arch or to impact coaxiality of the stented prosthesis at a canted native heart valve). One or more steering rods can also be used to assist in such steering. The shaft assembly includes one or more lumens through which the tension members and optional steering rods are received. To "steer" and direct a distal end of the delivery device, tension is applied to one or more respective tension members to subsequently shorten the respective length of tension member within the shaft assembly, which effectively pulls and bends the shaft assembly to a side of the shaft assembly in which the tensioned tension member is positioned. In addition, steering with one or more steering rods can be accomplished by inserting one or more rods into lumens of the shaft assembly to straighten the shaft assembly. In some embodiments, one or more lumens are provided in the outer sheath assembly to receive a respective rod to assist in reinforcing the outer sheath assembly and/or assist in steering the delivery device. Steering control of the tension members and/or rods can be manual or motorized, as desired.

Specific embodiments of the present disclosure are now described with reference to the figures, wherein like reference numbers indicate identical or functionally similar elements. The terms "distal" and "proximal" are used in the following description with respect to a position or direction relative to the treating clinician. "Distal" or "distally" are a position distant from or in a direction away from the clinician. "Proximal" and "proximally" are a position near or in a direction toward the clinician.

As described below, some aspects of the present disclosure relate to delivery devices utilizing one or more tension members to compress and retain a stented prosthesis during transcatheter delivery to a target site. By way of background, general components of one non-limiting example of a delivery device <NUM> with which some aspects of the present disclosure are useful are illustrated in <FIG>. The delivery device <NUM> is arranged and configured for percutaneously delivering a stented prosthesis, such a stented prosthetic heart valve <NUM> (schematically illustrated), to a target site. The delivery device <NUM> includes an optional outer sheath assembly <NUM> having a flexible outer sheath <NUM>, a flexible shaft assembly <NUM> and a handle assembly <NUM>. The shaft assembly <NUM> can include a distal portion <NUM> and define a continuous lumen <NUM> (referenced generally) sized to slidably receive an auxiliary component such as a guide wire <NUM>. In this embodiment, the outer sheath <NUM> is interconnected to a capsule <NUM> that is selectively disposed over the stented prosthesis <NUM> and assists in constraining the stented prosthesis <NUM> in the compressed arrangement. The capsule <NUM> can be retracted by the handle assembly <NUM> to expose the stented prosthesis <NUM> for deployment.

One or more tension members <NUM> (e.g., sutures, cords, wires or filaments) are further provided, and can be considered part of the delivery device <NUM> in some embodiments or as part of the stented prosthesis <NUM> in other embodiments. Examples in which the tension members <NUM> can be arranged are schematically illustrated in <FIG> (the stented prosthesis and other delivery device components being omitted in <FIG> for ease of illustration). One end of each of the tension members <NUM> can be secured proximate the handle assembly <NUM>, then each tension member <NUM> can extend distally to wrap around the stented prosthesis <NUM> positioned over the distal portion <NUM> to a release pin <NUM> positioned adjacent the stented prosthesis <NUM> and then back to the handle assembly <NUM> or other mechanism for maintaining and adjusting the desired level of tension in the tension members <NUM> either individually or in pairs or groups of tension members. Other tension member arrangements are envisioned. The delivery device <NUM> provides a loaded, compressed arrangement (<FIG>) in which the stented prosthesis <NUM> is loaded over the shaft assembly <NUM> and is compressively retained on the distal portion <NUM> by the tension members <NUM>. As is schematically illustrated in <FIG>, compression of the stented prosthesis <NUM> is adjustable with the tension members <NUM>. In this illustrated embodiment, the tension members <NUM> wrap around the stented prosthesis <NUM> normal to an axis of the shaft assembly <NUM>. Alternatively, the tension members <NUM> can be configured to wrap around the stented prosthesis <NUM> at other angles with respect to the axis of the shaft assembly <NUM>.

After being loaded, compressed and optionally sheathed with the capsule <NUM>, the stented prosthesis <NUM> is delivered to the native defective heart valve. Once the stented prosthesis <NUM> is sheathed with the capsule <NUM>, tension in the tension members <NUM> can be released, if desired, as the capsule <NUM> maintains the stented prosthesis <NUM> in the compressed arrangement. Once in position, the capsule <NUM> is retracted (if provided) and/or tension in the tension members <NUM> is lessened or released to permit the stented prosthesis <NUM> to self-expand to an expanded arrangement, partially releasing and ultimately fully deploying the stented prosthesis <NUM> from the shaft assembly <NUM> (see, <FIG>). Then, the release pin <NUM> is proximally retracted to disengage from the tension members <NUM> so that the tension members <NUM> can be released from the stented prosthesis <NUM> and withdrawn from the patient along with the delivery device <NUM>. In alternate embodiments, the release pin <NUM> is omitted and the tension members <NUM> can be cut for release from the stented prosthesis <NUM>. The present disclosure focuses on numerous ways to steer a delivery device, such as the delivery device <NUM>, during delivery of the stented prosthesis <NUM>, which can be particularly useful when navigating the delivery device around a patent's aortic arch to avoid vessel trauma. It is to be understood that the delivery device disclosed above is provided as only one example and that aspects of the disclosure can also be used with minimally invasive surgical devices that are delivered without the use of tension members. Moreover, aspects of the present disclosure can also be used with transcatheter prosthetic valves where the delivery is accomplished in multiple steps (i.e. first deploying a stent or dock with a skirt and then delivering a valve inside the implanted dock).

As referred to herein, stented prostheses useful with the various devices and methods of the present disclosure may assume a wide variety of configurations. For example, the stented prosthesis can be a bioprosthetic heart valve having tissue leaflets or a synthetic heart valve having polymeric, metallic or tissue-engineered leaflets, and can be specifically configured for replacing valves of the human heart. The stented prostheses of the present disclosure may include sent frames that are self-expandable, balloon expandable and/or mechanically expandable or combinations thereof. In general terms, stented prosthetic heart valves of the present disclosure include a stent or stent frame having an internal lumen maintaining a valve structure (tissue or synthetic), with the stent frame having a normal, expanded condition or arrangement and collapsible to a compressed condition or arrangement for loading within the delivery device. The stents or stent frames are support structures that comprise a number of struts or wire segments arranged relative to each other to provide a desired compressibility and strength to the prosthetic valve. The struts or wire segments are arranged such that they are capable of self-transitioning from, or being forced from, a compressed or collapsed arrangement to a normal, radially expanded arrangement. The struts or wire segments can be formed from a shape memory material, such as a nickel titanium alloy (e.g., Nitinol™). The stent frame can be laser-cut from a single piece of material, or can be assembled from a number of discrete components.

One non-limiting example of a stented prosthesis is the stented prosthetic heart valve <NUM> (hereinafter "prosthetic valve") illustrated in <FIG>. As a point of reference, the prosthetic valve <NUM> is shown in a normal or expanded arrangement in the view of <FIG> and a compressed arrangement in <FIG>. The prosthetic valve <NUM> includes a stent or stent frame <NUM> and a valve structure <NUM>. The stent frame <NUM> can assume any of the forms mentioned above, and is generally constructed to be self-expandable from the compressed arrangement to the normal, expanded arrangement. As discussed above, compression of the prosthetic valve <NUM> can be achieved with one or more tension members <NUM>.

The valve structure <NUM> of the prosthetic valve <NUM> can assume a variety of forms, and can be formed, for example, from one or more biocompatible synthetic materials, synthetic polymers, autograft tissue, homograft tissue, xenograft tissue, or one or more other suitable materials. In some embodiments, the valve structure <NUM> can be formed, for example, from bovine, porcine, equine, ovine and/or other suitable animal tissues. In some embodiments, the valve structure <NUM> is formed, for example, from heart valve tissue, pericardium, and/or other suitable tissue. In some embodiments, the valve structure <NUM> can include or form one or more leaflets <NUM>. For example, the valve structure <NUM> can be in the form of a tri-leaflet bovine pericardium valve, a bi-leaflet valve, or another suitable valve.

In some prosthetic valve constructions, such as that of <FIG>, the valve structure <NUM> can comprise two or three leaflets <NUM> that are fastened together at enlarged lateral end regions to form commissural joints, with the unattached edges forming coaptation edges of the valve structure <NUM>. The leaflets <NUM> can be fastened to a skirt that in turn is attached to the stent frame <NUM>. The prosthetic valve <NUM> includes a first end <NUM> and an opposing second end <NUM> of the prosthetic valve <NUM>. As shown, the stent frame <NUM> can have a lattice or cell-like structure, and optionally forms or provides posts <NUM> corresponding with commissures of the valve structure <NUM> as well as features <NUM> (e.g., crowns, eyelets or other shapes) at the first and second ends <NUM>, <NUM>. If provided, the posts <NUM> are spaced equally around the stent frame <NUM> (only one post <NUM> is clearly visible in <FIG>).

Turning now also to <FIG>, which schematically illustrates select components of a delivery device <NUM> that is largely similar to the delivery device <NUM> of <FIG> except as explicitly stated. In this embodiment, a shaft assembly <NUM> (which is truncated for ease of illustration) is configured to have two lumens 126a, 126b on opposite sides along the diameter of the shaft assembly <NUM>. In one lumen 126a, a guide wire <NUM> is positioned. In the second lumen 126b, one or more tension members <NUM> are threaded from the proximal end of the delivery device (e.g., from the handle assembly <NUM> or the like), through the shaft assembly <NUM> to and around a stented prosthesis positioned on the shaft assembly (e.g., on the distal portion <NUM>) and then back down to the proximal end of the delivery device <NUM>. During delivery of the stented prosthesis, the capsule can optionally be secured over the crimpled valve to maintain the prosthetic valve in a compressed condition (see also, the prosthetic valve <NUM> and capsule <NUM> disclosed previously). Then, tension in the tension members <NUM> can be eased or entirely released. When steering of the delivery device <NUM> is desired during delivery of the stented prosthesis one or more of the tension member(s) <NUM> can be pulled proximally, which will result in the shaft assembly <NUM> bending toward the side of the shaft assembly <NUM> on which the tension member(s) <NUM> are positioned (i.e. in the direction of the second lumen 126b as is shown in <FIG>). Bending of the shaft assembly <NUM> creates a smallest arch angle <NUM> proximate the second lumen 126b that houses the tensioned tension member(s) <NUM>. In this way, the tension member(s) <NUM> are used for both compressing the stented prosthesis as well as bending the shaft assembly <NUM>, which provides a steering capability of the delivery device <NUM>.

A truncated alternate shaft assembly <NUM>, which can be used as a replacement for any of the above-disclosed shaft assemblies, is illustrated in <FIG>, which includes first, second and third lumens 226a-c. Optionally, the lumens 226a-c can be equally sized and/or symmetrically arranged within the shaft assembly <NUM>. The first lumen 226a can receive a guide wire <NUM>, the second lumen 226b can house one or more tension members <NUM> and the third lumen can receive the release pin <NUM>, if provided. Similar to the prior disclosed embodiment, the tension members <NUM> can be tensioned to steer the delivery device in the direction of the second lumen 226b. As the tension members <NUM> are pulled proximally, the length of the tension member(s) <NUM> shortens, thus correspondingly bending the shaft assembly <NUM> to have a smallest arch angle <NUM> proximate the second lumen 226b.

Turning now also to <FIG>, which illustrates a truncated alternate shaft assembly <NUM> including a central lumen 326a surrounded by four outer lumens 326b. In the illustrated embodiment, which can be a substitute for any of the above-disclosed shaft assemblies, the outer lumens 326b are equally sized and symmetrically spaced about the central lumen 326a, however, equal sizing and symmetric spacing is not required. In various embodiments, a guide wire (e.g., guide wire <NUM> of <FIG>) is received within the central lumen 326a and one or more tension members are threaded through one or more of the outer lumens 326b, as desired. The arrangement of tension members (not shown, see also <FIG>) within the outer lumens 326b is selected to provide the desired steering capabilities. For example, if at least one tension member is positioned in each outer lumen 326b, the shaft assembly <NUM> can be steered in four directions by tensioning respective tension members within one outer lumen 326b. See <FIG>, for example, which helps illustrate that if tension members are threaded through each of the outer lumens 326b of <FIG>, the shaft assembly <NUM> can be steered "North", "East", "South" and "West" (i.e. <NUM> degrees, <NUM> degrees, <NUM> degrees, <NUM> degrees). It may be also desirable to tension two adjacent tension members, thus providing an additional four directions of steering capability (e.g., "Northeast" <NUM> degrees, "Southeast" <NUM> degrees, "Southwest" <NUM> degrees and "Northwest" <NUM> degrees).

Alternatively, fewer or more external lumens can be provided. For example, <FIG> illustrates a similar truncated shaft assembly <NUM> having one central lumen 426a surrounded by eight outer lumens 426b that are optionally equally sized and symmetrically spaced therearound (only a few of which are labeled for ease of illustration). A guide wire (e.g., guide wire <NUM>) can be received in the central lumen 426a and one or more tension members can be routed through the outer lumens 426b (tension members not shown for ease of illustration, see also, <FIG>). If select tension member(s) routed through one of the outer lumens 426b are tensioned, the shaft assembly <NUM> will bend and define a smallest arch angle of the shaft assembly <NUM> proximate respective outer lumen 426b housing the tensioned tension member(s). It is also possible to keep the possible number of steering directions less complex and to provide fewer steering direction options. In such an embodiment, multiple adjacent tension members can be configured to be pulled or tensioned simultaneously. As will be understood, the shaft assembly <NUM> can be used in place of any of the shaft assemblies disclosed herein.

As generally depicted in <FIG>, all embodiments disclosed herein can optionally include a steering rod <NUM> that can be inserted into one of the outer lumens 426b to further aid in steering the delivery device (e.g., delivery device <NUM>). For example, to counteract the tension member steering or correct other undesired bending of the shaft assembly <NUM>, the steering rod <NUM> can be pushed distally through at least one respective outer lumen 426b to stiffen and straighten the shaft assembly <NUM>. In alternate embodiments, the release pin <NUM> can also be arranged and configured to function as a steering rod. In such embodiments, the release pin <NUM> can be positioned from a proximal position to a distal position to straighten the length of the shaft assembly <NUM> at the location(s) in which the release pin <NUM> is distally advanced. In further embodiments, the release pin <NUM> can be tubular and a steering rod <NUM> can be pushed therethrough to straighten the shaft assembly <NUM> at the locations in which the steering rod <NUM> is inserted. Therefore, the steering rod embodiments disclosed herein are useful with delivery devices utilizing tension members for steering.

It is further envisioned that a plurality of steering rods can be used. Referring now also to <FIG>, which illustrates a truncated alternate shaft assembly <NUM> having a central lumen 526a through which a guide wire (e.g., guide wire <NUM>) can be received. Surrounding the central lumen 526a are ten outer lumens 526b that are optionally generally uniform in size and evenly spaced around the central lumen 526a. One or more tension members can be threaded through all or fewer than all of the outer lumens 526b (tension members not shown for ease of illustration, see also <FIG>). In this embodiment, two or more steering rods <NUM> are provided, which can be inserted into respective outer lumens 526b or the like to straighten and steer the shaft assembly <NUM>, as desired. Steering of the shaft assembly <NUM> can be accomplished in similar ways disclosed above with respect to prior embodiments.

Turning now also to <FIG>, which illustrates the cross-section of an alternate shaft assembly <NUM> that can be used as an alternative for any shaft assembly disclosed herein. The shaft assembly <NUM> includes a lumen 626a, which is surrounded by a plurality of lumens 626b (only a few of which are referenced for ease of illustration). In this embodiment, the lumens 626a-b are offset and asymmetrical with respect to a central axis A of the shaft assembly <NUM>. It will be understood that this is one example of how the lumens 626a-b can be arranged and configured and that any of the above-referenced embodiments can be similarly arranged to be off-center and asymmetrical. Similar to prior embodiments, one or more straightening rods 660a can be inserted within the lumens 626a-b to steer the inner shaft <NUM> in the manner described above with respect to the embodiments. The shaft assembly <NUM> also includes optional spines or rods 660b positioned in respective lumens 626c, which extend through a length of the shaft assembly <NUM>. The rods 660b have a stiffness greater than that of the material of the shaft assembly <NUM> and the rods 660b can either be permanently fixed within the shaft assembly <NUM> to provide stiffening, alignment and support to the shaft assembly <NUM> or, alternately, the rods 660b can be removably insertable within their respective lumens 626c.

The steering rods or rods disclosed herein can take a variety of shapes. In many of the embodiments disclosed above, the rods have a flexible cylinder or wire form configuration. In alternate embodiments, such as that shown in <FIG>, a rod <NUM> can have a cross-section defining a plurality of radially-extending supports <NUM> (only a few of which are referenced for ease of illustration). In other words, the illustrated embodiment is configured to include a cross-section or end view having sinewave imposed on the radius of a circle. The embodiment of <FIG> is beneficial in that the supports <NUM> provide reduced surface contact with the respective lumen (e.g., any lumen disclosed herein) as compared to a cylindrical rod, which makes it easier to slide the rod <NUM> within the respective lumen. Other support <NUM> configurations are also envisioned.

To further reduce friction between a lumen and any element inserted therein, any of the shaft assembly lumens disclosed herein can optionally be configured to include a coating (not visible). The coating can be a low-friction coating such as high-density polyethylene (HDPE), polytetrafluoroethylene (PTFE) or the like to ease insertion of any disclosed rods or tension members. The coating can cover all of part of the surface defining the lumen, as desired.

Turning now also to <FIG>, which illustrates an alternate lumen <NUM> and rod <NUM>, which are collectively configured to provide a rod <NUM>, which is restricted to unidirectional movement within the lumen <NUM>. In this embodiment, the lumen <NUM> is formed within a resilient material of the shaft assembly <NUM>. The lumen <NUM> is configured to define a plurality of circumferential grooves <NUM> (only a few of which are referenced) that narrow a diameter of the lumen <NUM> along a length of the lumen at the grooves <NUM>. Therefore, the lumen <NUM> has a varying internal diameter along its length. The rod <NUM> is configured to include a plurality of protrusions <NUM>, positioned between a distal head <NUM> and a proximal end <NUM>. The protrusions <NUM>, distal head <NUM> and proximal end <NUM> can be generally conical in shape so that the rod <NUM> can be pushed distally past the grooves <NUM> to advance the rod <NUM> but the grooves <NUM> will catch on circular end surface <NUM>, <NUM>, <NUM> of the protrusions <NUM>, distal head <NUM> and proximal end <NUM>, respectively, if the rod <NUM> is urged in the proximal direction.

Turning now also to <FIG>, which collectively illustrate the outer sheath assembly <NUM> of <FIG> configured to receive one or more rods <NUM> via lumens <NUM> provided within the outer sheath assembly <NUM> (the outer sheath <NUM> and capsule <NUM> are shown as transparent for ease of illustration). Two lumens <NUM> are illustrated in <FIG>, however, it will be understood that fewer or more lumens can be provided and the lumens <NUM> can be positioned in different circumferential locations in the capsule <NUM> and/or outer sheath <NUM>, as desired. Each rod(s) <NUM> can be selectively inserted within one respective lumens <NUM> to increase the strength and support the capsule <NUM> for loading or recapture of the stented prosthesis, for example. The rod(s) <NUM> can be distally advanced and/or retracted within respective lumens <NUM>, as desired, to allow for selective stiffening of portions of the outer sheath assembly <NUM>. The rod(s) <NUM> and lumen(s) <NUM> can take the configuration of any rod and lumen disclosed herein with respect to other embodiments. For example, the lumen(s) <NUM> can optionally include a coating to reduce friction, as discussed above. It will further be understood that when the outer sheath assembly <NUM> is provided, tension members <NUM> are optional and may not be required to adequately compress the stented prosthesis for delivery (see also, <FIG>). It will further be understood in view of this disclosure that although the outer sheath assembly <NUM> is described in the context of use with the delivery device <NUM> of <FIG>, the outer sheath assembly <NUM> described with respect to <FIG> can be used with other delivery devices.

All embodiments disclosed herein can optionally be steered by sequentially releasing or tightening the one or more tension members in order to retain a particular orientation. In addition, all of the disclosed embodiments can include have one or more additional tension members running through the central lumen in various points that would either attach to the stent frame (e.g., eyelet) or a distal tip of the delivery device. This optional configuration would allow the user to steer the stented prosthesis to a desired orientation. In such embodiments, the tension members can be wrapped around the stented prosthesis at various angles with respect to a central axis of the shaft assembly to accomplish desired steering capabilities.

The number of lumens in the shaft assembly for receiving one or more tension members, release pins and/or steering rods or the like can, in some embodiments, be dictated by the number of tension members circumscribing the stented prosthesis. For example, in one example embodiment, three tension members circumscribe the stented prosthesis and three outer lumens can be provided in the shaft assembly such that each tension member tracks up to the stented prosthesis and the back down a single lumen. In other embodiments utilizing three tension members, six lumens can be provided in the shaft assembly such that each tension member is maintained in two lumens, one for a first length of tension member extending to the stented prosthesis and one adjacent lumen for a second length of a tension member extending from the stented prosthesis back toward the handle assembly. Similarly, four tension members can be managed with either four or eight lumens provided in the shaft assembly, and so on. The disclosure is not intended to be limited to any number of tension members, lumens or steering rods utilized nor is the disclosure intended to be limited to any specific arrangement thereof within a shaft assembly.

The disclosed embodiments can be motorized to control the steering of one or more tension members and/or rods. By controlling the tension of each rod and/or tension member with a motor, a user interface for steering can be simplified, which may be particularly desirable in embodiments having a large number of actuators for controlling the tensioning of each tension member and/or movement of each steering rod. In further embodiments, a joystick or the like can be utilized to direct and control a <NUM> degree steering range of the shaft assembly.

Further embodiments can include a device to limit the amount of tension that can be applied to the tension members to prevent damage to the device, which could compromise the procedure. Such tension limiting devices can include a drag washer system, similar to that used in fishing reels or the tension management devices disclosed in <CIT>. In further various embodiments, a motor of the handle assembly that powers an actuator that controls movement of the tension members, rod and, perhaps, other components of the delivery device, can be used to limit tension by utilizing a voltage sensor or by implementing a load cell on the actuator, for example.

Claim 1:
A delivery device (<NUM>, <NUM>) for delivering a stented prosthesis (<NUM>) to a native heart valve; the delivery device comprising:
a shaft assembly (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>) configured to retain the stented prosthesis (<NUM>), the shaft assembly including at least one lumen (126a, 126b, 226a, 226b, 226c, 326a, 326b); and
at least one tension member (<NUM>) extending through the lumen (126a, 126b, 226a, 226b, 226c, 326a, 326b) and securing the stented prosthesis (<NUM>) to the shaft assembly (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>); wherein the at least one tension member can be varied to correspondingly vary compression of the stented prosthesis (<NUM>); wherein one or more of the at least one tension members (<NUM>) can be further tensioned to steer the shaft assembly (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>).