Patent Description:
The present technology is generally related to delivery devices and methods for transcatheter delivery and deployment of a prosthesis to a heart valve.

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 a prosthetic heart valve or prosthesis on the beating heart, intending to obviate the need for the use of classical sternotomy and cardiopulmonary bypass. In general terms, an expandable prosthetic valve 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.

The heart valve prosthesis employed with catheter-based, or transcatheter, procedures generally includes an expandable multi-level frame or stent that supports a valve structure having a plurality of leaflets. The frame can be contracted during percutaneous transluminal delivery, and expanded upon deployment at or within the native valve. One type of valve stent can be initially provided in an expanded or uncrimped arrangement, then crimped or compressed about a balloon portion of a catheter. The balloon is subsequently inflated to expand and deploy the prosthetic heart valve. With other stented prosthetic heart valve designs, the stent frame is formed to be self-expanding. With these systems, the valved stent is crimped down to a desired size and held in that compressed state within a sheath for transluminal delivery. Retracting the sheath from this valved stent allows the stent to self-expand to a larger diameter, fixating at the native valve site. In more general terms, then, once the prosthetic valve is positioned at the treatment site, for instance within an incompetent native valve, the stent frame structure may be expanded to hold the prosthetic valve firmly in place.

The present disclosure addresses problems and limitations associated with the related art. <CIT> describes hydraulic delivery systems for prosthetic heart valve devices.

The techniques of this disclosure generally relate to delivery devices and methods for transcatheter delivery and deployment of a prosthesis, such as a prosthetic heart valve, to a defective heart valve. Aspects of the disclosure are particularly beneficial for transcatheter edge-to-edge tricuspid repair as various delivery devices are configured to reduce the depth in which the device needs to be inserted into the right ventricle during delivery of the prosthesis. Access to a tricuspid valve can be challenging in that existing implanted devices may be in the anatomy, reducing the space available for the delivery device. In addition, visualization of the delivery system and implant may be challenging as metallic capsules can cause artifacts due to density. Further, chordae, papillary muscles serve as obstacles for delivery and the right ventricle is generally shorter than the left ventricle. All of these considerations result in a general desire for a delivery device capable of delivering an implant to a tricuspid valve while reducing a length the delivery device extends into the right ventricle. Aspects of the disclosure are also suitable for the delivery of other cardiovascular implants or gastrointestinal stents, for example.

In one aspect, the present disclosure provides a delivery device including a handle assembly and a piston mount having a distal portion. The distal portion includes a stop extending radially from and fixed to the distal portion. Additionally, the delivery device includes a capsule assembly including a helical compression spring and a plurality of retraction members secured about a distal end of the compression spring. Tensioning of the retraction members compresses the compression spring against the stop.

In an example (not claimed), the disclosure provides methods including providing a delivery device including a handle assembly, a piston mount connected to the handle assembly and having a distal portion terminating at a nose cap. The distal portion includes a stop extending radially from and fixed to the distal portion. The delivery device further includes a capsule assembly including a biasing element and a plurality of retraction members secured about a distal end of the biasing element. An implant is compressed onto the piston mount and within the capsule assembly. The method further includes delivering the implant to a heart valve with the delivery device and tensioning the retraction members to collapse the biasing element against the stop to partially unsheathe the implant. In addition, the method includes distally advancing the nose cap to fully unsheathe the implant and release the implant from the delivery device. Aspects of the discourse also include methods of loading an implant to a delivery device.

The invention relates to a delivery device as defined by claim <NUM>. 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 referred to herein, implants, stented prostheses, stented prosthetic heart valves or "prosthetic valves" useful with the various systems, devices and methods of the present disclosure may assume a wide variety of configurations. Stented prosthetic heart valves can include, for example, 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 prosthetic valves and stented prostheses of the present disclosure may be self-expandable, balloon expandable and/or mechanically expandable or combinations thereof. In general terms, the prosthetic 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 an uncompressed, expanded condition or arrangement and collapsible to a compressed condition or arrangement for loading within the delivery device. For example, 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 or implant <NUM> suitable for use with systems and devices of the disclosure is illustrated in <FIG>. In this example, the implant is a prosthetic heart valve <NUM> including a valve support <NUM>, an anchoring member <NUM> attached to the valve support <NUM>, and a prosthetic valve assembly <NUM> within the valve support <NUM>. Referring in particular to <FIG>, the valve support <NUM> has an inflow region <NUM> and an outflow region <NUM>. The prosthetic valve assembly <NUM> is arranged within the valve support <NUM> to allow blood to flow from the inflow region <NUM> through the outflow region <NUM> (arrows BF), but prevent blood from flowing in a direction from the outflow region <NUM> through the inflow region <NUM>.

The anchoring member <NUM> includes a base <NUM> attached to the outflow region <NUM> of the valve support <NUM> and a plurality of arms <NUM> projecting laterally outward from the base <NUM>. The anchoring member <NUM> also includes a fixation structure <NUM> extending from the arms <NUM>. The fixation structure <NUM> can include a first portion <NUM> and a second portion <NUM>. The first portion <NUM> of the fixation structure <NUM>, for example, can be an upstream region of the fixation structure <NUM> that, in a deployed configuration as shown in <FIG>, is spaced laterally outward apart from the inflow region <NUM> of the valve support <NUM> by a gap G. The second portion <NUM> of the fixation structure <NUM> can be a downstream-most portion of the fixation structure <NUM>. The fixation structure <NUM> can be a cylindrical ring (e.g., straight cylinder or conical), and the outer surface of the fixation structure <NUM> can define an annular engagement surface configured to press outwardly against the native heart valve annulus. The fixation structure <NUM> can further include a plurality of fixation elements <NUM> that project radially outward and are inclined toward an upstream direction. The fixation elements <NUM>, for example, can be barbs, hooks, or other elements that are inclined only in the upstream direction (e.g., a direction extending away from the downstream portion of the implant <NUM>).

The anchoring member <NUM> has a smooth bend <NUM> between the arms <NUM> and the fixation structure <NUM>. For example, the second portion <NUM> of the fixation structure <NUM> extends from the arms <NUM> at the smooth bend <NUM>. The arms <NUM> and the fixation structure <NUM> can be formed integrally from a continuous strut or support element such that the smooth bend <NUM> is a bent portion of the continuous strut. In other examples, the smooth bend <NUM> can be a separate component with respect to either the arms <NUM> or the fixation structure <NUM>. For example, the smooth bend <NUM> can be attached to the arms <NUM> and/or the fixation structure <NUM> using a weld, adhesive or other technique that forms a smooth connection. The smooth bend <NUM> is configured such that the implant <NUM> can be recaptured in a capsule or other container after the implant <NUM> has been at least partially deployed.

The implant <NUM> can further include a first sealing member <NUM> on the valve support <NUM> and a second sealing member <NUM> on the anchoring member <NUM>. The first and second sealing members <NUM>, <NUM> can be made from a flexible material, such as a polymeric material. The first sealing member <NUM> can cover the interior and/or exterior surfaces of the valve support <NUM>. The first sealing member <NUM> is attached to the interior surface of the valve support <NUM>, and the prosthetic valve assembly <NUM> is attached to the first sealing member <NUM> and commissure portions of the valve support <NUM>. The second sealing member <NUM> is attached to the inner surface of the anchoring member <NUM>. As a result, the outer annular engagement surface of the fixation structure <NUM> is not covered by the second sealing member <NUM> so that the outer annular engagement surface of the fixation structure <NUM> directly contacts the tissue of the native annulus.

The implant <NUM> can further include an extension member or brim <NUM>. The extension member <NUM> can be an extension of the second sealing member <NUM>, or it can be a separate component attached to the second sealing member <NUM> and/or the first portion <NUM> of the fixation structure <NUM>. The extension member <NUM> can be a flexible member that, in a deployed state as shown in <FIG>, flexes relative to the first portion <NUM> of the fixation structure <NUM>. In operation, the extension member <NUM> guides the implant <NUM> during implantation such that the device is located at a desired elevation and centered relative to the native annulus. In some embodiments, one or more components of the extension member <NUM> can be made of or include a radiopaque material.

As best shown in <FIG>, valve support <NUM> defines a first frame (e.g., an inner frame) and fixation structure <NUM> of the anchoring member <NUM> defines a second frame (e.g., an outer frame) that each include a plurality of structural elements. The fixation structure <NUM>, more specifically, includes structural elements <NUM> arranged in diamond-shaped cells <NUM> that together form at least a substantially cylindrical ring when freely and fully expanded as shown in <FIG>. The structural elements <NUM> can be struts or other structural features formed from metal, polymers, or other suitable materials that can self-expand or be expanded by a balloon or other type of mechanical expander.

The fixation structure <NUM> can be a generally cylindrical fixation ring having an outwardly facing engagement surface. For example, in the example shown in <FIG>, the outer surfaces of the structural elements <NUM> define an annular engagement surface configured to press outwardly against the native annulus in the deployed state. In a fully expanded state without any restrictions, the fixation structure <NUM> is at least substantially parallel to the valve support <NUM>. However, the fixation structure <NUM> can flex inwardly (arrow I) in the deployed state when it presses radially outwardly against the inner surface of the native annulus of a heart valve.

The first sealing member <NUM> lines the interior surface of the valve support <NUM>, and the second sealing member <NUM> along the inner surface of the fixation structure <NUM>. The extension member <NUM> has a flexible web <NUM> (e.g., a fabric) and a support member <NUM> (e.g., metal or polymeric strands) attached to the flexible web <NUM>. The flexible web <NUM> can extend from the second sealing member <NUM> without a metal-to-metal connection between the fixation structure <NUM> and the support member <NUM>. For example, the extension member <NUM> can be a continuation of the material of the second sealing member <NUM>. Several embodiments of the extension member <NUM> are thus a floppy structure that can readily flex with respect to the fixation structure <NUM>. The support member <NUM> can have a variety of configurations and be made from a variety of materials, such as a double-serpentine structure made from Nitinol. Additional details regarding the implant <NUM> can be found in <CIT>.

In one example, the implant <NUM> has a diameter of <NUM> in the expanded arrangement for delivery within a <NUM> French capsule or the like. In another example, the implant <NUM> has a diameter of <NUM> in the expanded arrangement.

Referring now in addition to <FIG>, which illustrate select components of a delivery device <NUM> suitable for transcatheter delivery of an implant or prosthesis, such as that of <FIG>. In general terms, the delivery device <NUM> includes a handle assembly <NUM> supporting an optional outer sheath <NUM> and/or an optional inner catheter <NUM>, The delivery device includes a piston mount <NUM>, which may be provided within the inner catheter <NUM>. The piston mount <NUM> may support a piston or valve retainer <NUM> (not visible) within a nose cap <NUM> that may be of any of the type known in the art for releasably retaining an implant compressed within a catheter or the like. The piston mount <NUM> can be an elongated shaft or catheter, for example. Over a distal end <NUM> of piston mount <NUM>, a capsule assembly <NUM> may be provided that is configured to transition from a loaded arrangement in which the capsule assembly <NUM> compressively sheathes the implant to a partially-deployed arrangement in which the capsule assembly is at least partially withdrawn from the implant, to a deployed arrangement in which the implant is fully unsheathed from the capsule assembly so that the implant can expand, releasing the implant from the piston and the delivery device <NUM>. In various embodiments of the disclosure, the capsule assembly <NUM> includes a biasing element <NUM> that is a helical compression spring and two or more retraction wires <NUM> secured to the biasing element <NUM> and which may extend proximally for tensioning to correspondingly pull the biasing element against its bias to unsheathe the implant <NUM>. At the distal end <NUM> of the piston mount <NUM>, distal to the capsule assembly <NUM>, a nose cap <NUM> can be provided. In some embodiments, the capsule assembly <NUM> may at least partially be positioned within the nose cap <NUM> in the loaded arrangement (<FIG>) and in other examples, the capsule assembly <NUM> may merely abut or otherwise terminate proximal to the nose cap <NUM> in the loaded arrangement. In non-limiting examples, the nose cap <NUM> can have a length of about <NUM> (+<NUM>/-<NUM>), which greatly minimizes a depth in which the delivery device <NUM> needs to be deployed into the right ventricle during a transcatheter tricuspid replacement procedure and can reduce anatomical interactions, particularly for small and/or curved right ventricles. In some examples, the nose cap <NUM> is tapered in a distal direction.

Actuation of the retraction members <NUM> can be mechanically accomplished by tensioning the retraction members <NUM>. In another example, the retraction wires <NUM> can be tensioned using a first fluid path <NUM> connected to a first fluid source 242a as is depicted in <FIG>, which can also be configured to recapture the implant <NUM> within the capsule assembly <NUM>. With one hydraulically driven device <NUM>, once implant position is finalized within the patient anatomy, fluid from a second inflation device or connection 242b may be injected into a second fluid path <NUM> configured to deploy the implant <NUM> by releasing the implant from the piston/valve retainer <NUM>. Fluid may be directed through the second fluid path <NUM> into the nose cap <NUM> to push the nose cap distally into the ventricle, for example, releasing the implant <NUM> from the delivery device <NUM> and allowing for full deployment of the implant. It is further envisioned that tensioning of the retraction members <NUM> can be pneumatically or mechanically achieved.

The capsule assembly <NUM> can take many forms. Referring in addition to <FIG>, which illustrate the piston mount <NUM> supporting an implant (e.g., implant <NUM>) compressed thereon and retained with the piston <NUM> (not visible). In one example, the capsule assembly <NUM> includes the biasing element <NUM> being a helical compression spring or the like, that is biased against compression of the biasing element. The plurality of elongated retraction members <NUM> (generally referenced) are secured to the biasing element <NUM> via any suitable method including, but not limited to, welding or crimping. In the illustrated example, four retraction members <NUM> are provided although not all retraction members are visible in the drawings. In other examples, between <NUM>-<NUM> retraction members <NUM> are provided. Each retraction member <NUM> can be a wire, cord, filament or the like. In one example, the retraction members <NUM> are approximately equally spaced (+/- <NUM> degrees). Each retraction member <NUM> is secured to the biasing element <NUM>, at a distal end 238a of the biasing element <NUM>. In one example, the retraction members <NUM> are brought together or joined at a proximal end 238b of the biasing element <NUM>. The retraction members <NUM> or elongated member <NUM> interconnecting the retraction members <NUM> may extend proximally to the handle assembly <NUM> for tensioning to transition the capsule assembly <NUM> from the loaded arrangement to the deployed arrangement. Proximal movement and tensioning of the retraction members <NUM> may correspondingly pull the biasing element <NUM> proximally to compress the biasing member <NUM> and unsheathe the implant <NUM> for expansion and deployment in the process as is generally shown in <FIG>.

In one embodiment, the piston mount <NUM> includes a stop <NUM> that is secured to the piston mount <NUM> and extends radially therefrom. In one example, the stop <NUM> is positioned between the biasing element <NUM> and the inner catheter <NUM>. The stop <NUM> is configured to restrict movement of the biasing element <NUM> proximally past the stop <NUM>. In this way, the stop <NUM> can be made of a metal or rigid polymer, for example. The stop <NUM> can be one of many configurations suitable for this purpose. In the example of <FIG>, the stop <NUM> can include a central aperture <NUM> through which the piston mount <NUM> can be threaded and/or notches or grooves <NUM> within a periphery surface <NUM> of the stop <NUM> in which one respective retraction member <NUM> can be positioned. In the example of <FIG>, an alternate stop <NUM>' can include apertures <NUM>' provided through a thickness of the stop through which the retraction members <NUM> extend as they are tensioned. Alternatively, if the retraction members <NUM> are joined as shown in <FIG>, for example, one or more apertures can be provided in the stop to receive the elongated member <NUM>. It will be understood that the number and placement of notches and apertures can vary depending on the number and orientation of the retraction members provided.

The biasing element <NUM> of the disclosure can take many configurations. Generally, the biasing member <NUM> can include any structure that biases both the capsule assembly <NUM> against compression along a length of the capsule assembly. Therefore, the biasing element <NUM> has a natural arrangement in which the biasing element is not exposed to external forces and a compressed arrangement in which the biasing element is compressed against its bias to reduce its length as compared to the natural arrangement. In one example, the biasing element <NUM> is a helical compression spring formed of a round wire or a flat wire, in particular that is about <NUM> thick (+/-<NUM>) so that any cleat/feature protrusion of the implant (typically between <NUM>-<NUM>) would be within the profile of the spring wire of the helical compression spring biasing element <NUM> when the implant <NUM> is compressed within the biasing element <NUM>. In one example, the biasing element <NUM> has a length of about <NUM> (+/- <NUM>) in the natural arrangement to fully cover the atrial and intra-annular segments of the implant <NUM>, assuming the implant has approximately a <NUM> intra-annular frame and <NUM> brim <NUM> length in the compressed arrangement. Further wire forming the biasing element <NUM> can be radiused to be atraumatic to the anatomy and the implant <NUM>.

In various examples, a pitch of the wire forming a biasing element <NUM> can be set to hold the implant <NUM> in a compressed configuration until the implant <NUM> is deployed while maintaining gaps <NUM> (generally referenced in <FIG>) between wraps <NUM> (generally referenced in <FIG>) to allow for visualization during the procedure and lessens echogenic shadowing under ultrasound as compared to a denser metal capsule design. In one example, the gap <NUM> between wraps <NUM> is at least equivalent to the width of the wire and up to <NUM> when the biasing element <NUM> is in a natural arrangement. In various examples, any metal components of the delivery device <NUM>, such as the biasing element <NUM>, can include a dimpled or otherwise textured surface to provide echogenic attributes. The present inventors have found that gaps <NUM> formed between wraps <NUM> of the helical compression spring are beneficial in that they provide enhanced visualization of the capsule assembly <NUM> as compared to metallic sheath capsules that are more likely to cause artifacts due to their metallic density.

Referring now in addition to <FIG>, the biasing element <NUM> can optionally be configured specifically to accommodate attributes of the particular implant to be delivered. For example, if the implant <NUM> (<FIG>) has a lower outwardly radial force at an area A1 at its proximal end or brim <NUM> as compared to an area A2 at the distal, outflow region <NUM> of the implant <NUM>, a biasing element <NUM> can optionally have the corresponding attributes of <FIG>. For example, a proximal end 338a of the biasing element <NUM> may have an area A3 having a lower pitch as compared to an area A4 a distal end 338b of the biasing element. As shown in <FIG>, an area A5 at a proximal end 438a of biasing element <NUM> can be made of a thinner wire as compared to an area A6 at a distal end 438b of the biasing element <NUM>. Other illustrative examples include a biasing element having varying pitch, filar count, material composition or wire thickness, for example. The respective transition points for changes in pitch, filar count, material composition or wire thickness can correspond to transition points along a length L of the implant <NUM> when the implant is in the compressed arrangement. It will be understood that biasing elements of the disclosure can be modified to suit other particular implant forces in a similar manner. Further, it is to be understood that the features of all of the biasing elements disclosed herein are combinable and interchangeable.

Referring now in addition to <FIG>, in various embodiments of the disclosure, the capsule assembly <NUM> can optionally include a sleeve <NUM> covering the biasing element <NUM>. A few non-limiting examples of materials suitable for the sleeve <NUM> include thermoplastic polyurethanes or polyether block amide <NUM>/<NUM>. The sleeve <NUM> is beneficial in that it can protect the anatomy from implant <NUM> features until the implant is ready for deployment. In such an embodiment, the biasing element <NUM> holds the implant <NUM> in a crimped configuration until deployment while maintaining gaps <NUM> between helical spring wraps <NUM> to allow for visualization of the capsule assembly <NUM> during deployment of the implant <NUM>.

Referring now in addition to <FIG>, which illustrate one method of loading an implant (e.g., implant <NUM>) to the delivery device <NUM> of <FIG>. In this example, the biasing element <NUM> is positioned and compressed such that both distal and proximal ends 238a, 238b of the biasing element <NUM> are adjacent the nose cap <NUM> (<FIG>). Then, the implant <NUM> is loaded over the piston mount <NUM> and crimped to compress the implant using any known technique (<FIG>). In one example, the implant <NUM> is loaded onto piston <NUM> (see also, <FIG>). Next, compression of the biasing element <NUM> is released at a controlled rate to allow the biasing element to expand and sheathe the implant <NUM>. In some methods, at least part of the capsule assembly <NUM> remains in the nose cap <NUM> as the biasing element <NUM> is allowed to expand. If the implant <NUM> includes cleats, the biasing element <NUM> is released in the same direction as the cleats to prevent snagging (<FIG>). Then, the retraction wires <NUM> can be attached to the distal end 238a of the biasing element <NUM> (<FIG>). If applicable, piston <NUM> can be then be fixed to any implant retention features (e.g., T-bars or the like as known in the art) and the nose cap <NUM> can be moved proximally to lock the implant <NUM> in place, compressed within the capsule assembly <NUM> (<FIG>). Optionally, the nose cap <NUM> can be moved proximally to at least partially cover the capsule assembly <NUM>, including covering one or more of the biasing element <NUM>, one or more retraction members <NUM> and/or any sleeve <NUM>.

Referring in addition now to <FIG>, which schematically illustrates one method of the disclosure. In this example, an implant (e.g., implant <NUM>) is crimped and loaded onto the piston mount <NUM> of the delivery device <NUM> having the capsule assembly <NUM> sheathing the implant <NUM> as shown in <FIG>. The physician then advances the delivery device <NUM> via transcatheter procedure from the interior vena cava IVC into the right atrium RA of a patient's heart. The nose cap <NUM> can optionally be connected to steering components, as used in the art, used to steer the nose cap during delivery. The nose cap <NUM> can be steered through the tricuspid valve annulus TV until the compressed, loaded implant <NUM> is within the tricuspid valve annulus TV. Proper positioning of the implant <NUM> in the right atrium RA, proximal to the annulus TV can be confirmed via imaging techniques. Once the physician navigates the implant <NUM> to the desired position, the implant <NUM> can be transitioned to a partially expanded arrangement by proximally withdrawing and compressing the distal end 238a of the biasing element <NUM> against the stop <NUM> by tensioning the retraction members <NUM>. Partial, unsheathing of the implant <NUM> will cause the proximal end or brim <NUM> of the implant <NUM> to expand outwardly. Optionally, the biasing element <NUM> position can be monitored via fluoroscopy. If desired, tension in the retraction members <NUM> can be lessened to at least partially recapture the implant <NUM> within the capsule assembly <NUM> for recovery or repositioning of the implant <NUM>, as desired. When the implant <NUM> is in the desired location, the nose cap <NUM> can be advanced distally via actuation at the handle assembly <NUM>, thereby freeing the implant <NUM> from the piston <NUM> and delivery device <NUM>. The implant <NUM> is then fully seated in the patient's anatomy. The nose cap <NUM> and piston mount <NUM> can be proximally retracted through the implant <NUM> and the delivery system can be withdrawn from the patient in the same manner as delivered.

In methods where the implant is a replacement tricuspid valve and the implantation site is a tricuspid valve, only the nose cap will be deployed into the right ventricle (a length of about <NUM>-<NUM>), which is generally a <NUM>-<NUM>% reduction in depth that the device deploys into the right ventricle as compared to a traditional sheath capsule, which can have a length of about <NUM>. Due to the reduction in right ventricle deployment depth, devices of the disclosure are suitable for a wider number of patient anatomies. In addition, the smaller, tapered nose cap reduces the risk of anatomical interactions, which are more common with tricuspid valve replacement procedures.

Referring in addition now to <FIG>, which schematically illustrates another method of the disclosure. In this example, an implant (e.g., implant <NUM>) is crimped and loaded onto the piston mount <NUM> of the delivery device <NUM> having the capsule assembly <NUM> sheathing the implant <NUM> as shown in <FIG>. The physician then advances the delivery device <NUM> via transcatheter procedure into the left atrium LA of a patient's heart. The nose cap <NUM> can optionally be connected to steering components, as used in the art, used to steer the nose cap during delivery. The nose cap <NUM> can be steered through a mitral valve annulus MV until the compressed, loaded implant <NUM> is within the mitral valve annulus MV. Proper positioning of the implant <NUM> in the left atrium LA, proximal to the annulus MV can be confirmed via imaging techniques. Once the physician navigates the implant <NUM> to the desired position, the implant <NUM> can be transitioned to a partially expanded arrangement by proximally withdrawing and compressing the distal end 238a of the biasing element <NUM> against the stop <NUM> by tensioning the retraction members <NUM>. Partial, unsheathing of the implant <NUM> will cause the proximal end or brim <NUM> of the implant <NUM> to expand outwardly. Optionally, the biasing element <NUM> position can be monitored via fluoroscopy. If desired, tension in the retraction members <NUM> can be lessened to at least partially recapture the implant <NUM> within the capsule assembly <NUM> for recovery or repositioning of the implant <NUM>, as desired. When the implant <NUM> is in the desired location, the nose cap <NUM> can be advanced distally via actuation at the handle assembly <NUM>, thereby freeing the implant <NUM> from the piston <NUM> and delivery device <NUM>. The implant <NUM> is then fully seated in the patient's anatomy. The nose cap <NUM> and piston mount <NUM> can be proximally retracted through the implant <NUM> and the delivery system can be withdrawn from the patient in the same manner as delivered. In one example, only the nose cap <NUM> is advanced into the left ventricle LV during the procedure as the capsule assembly <NUM> will remain in the left atrium. In one example, the delivery device does not extend further than <NUM> into a left ventricle adjacent the mitral valve during the release of the implant.

Claim 1:
A delivery device (<NUM>) comprising:
a handle assembly (<NUM>);
a piston mount (<NUM>) having a distal portion, the distal portion including a stop (<NUM>) extending radially from and fixed to the distal portion; and
a capsule assembly (<NUM>) including a helical compression spring (<NUM>) and a plurality of retraction members (<NUM>) secured about a distal end of the compression spring; wherein tensioning of the retraction members compresses the compression spring against the stop.