CN115461016A

CN115461016A - Transcatheter valve leaflet replacement devices, delivery, guidance and fixation systems and methods thereof

Info

Publication number: CN115461016A
Application number: CN202180031063.1A
Authority: CN
Inventors: T·范; C·马丁; N·哈米德
Original assignee: Shuqia Medical Co
Current assignee: Shuqia Medical Co
Priority date: 2020-03-11
Filing date: 2021-03-10
Publication date: 2022-12-09
Also published as: WO2021183679A1; EP4117584A4; EP4117584A1; JP2023517066A

Abstract

A transcatheter heart valve leaflet replacement system includes a valve prosthesis and a multi-stage multi-lumen (MSML) heart valve delivery and implantation system for guiding and implanting the prosthesis to a native annulus. The prosthesis comprises: a stent frame including an upper atrial flare portion and a lower ventricular portion, a plurality of prosthetic leaflets, and at least one liner skirt. The prosthesis is configurable or otherwise sized to fit in an MSML delivery and implantation system and then selectively expanded to an operative size and position after being deployed within the annulus. Portions of the prosthesis may be configured to couple with a Dual Guide and Fixation (DGF) member to guide and fix the prosthesis to the annulus. In one aspect, the MSML delivery and implantation system includes a primary docking system, a DGF member delivery system, and a valve containment, positioning and locking system.

Description

Transcatheter valve leaflet replacement devices, delivery, guidance and fixation systems and methods thereof

Cross Reference to Related Applications

This application claims the benefit of co-pending U.S. provisional application serial No. 62/988,253 filed on day 3, 11 of 2020 and is a partial continuation of co-pending application serial No. 15/453,518 filed on day 3, 8 of 2017, which claims the benefit of 62/305,204 filed on day 2016 of 2016 3, 8 of 2016, 62/413,693 filed on day 27 of 2016, 10, 27 of 2016 and 62/427,551 filed on day 11, 29 of 2016 and is a partial continuation of co-pending application serial No. 17/121,615 filed on day 14 of 2020, 12, 615, which is a continuation of international application No. PCT/US2019/037476 filed on day 17 of 2019, which claims the benefit of U.S. provisional application No. 62/685,378 filed on day 15 of 2018, 6, 15 of 2018, the disclosures of which (including the specification and drawings) are all hereby incorporated by reference in their entirety.

Technical Field

The present application relates generally to transcatheter implantation of heart valve replacement systems and prosthetic heart valves, e.g., for replacing diseased mitral and/or tricuspid valves in humans or animals. More particularly, embodiments of the present subject matter relate to tissue-based valve leaflet replacement systems and methods of operably delivering and securing a leaflet replacement valve in its target location.

Background

The Mitral Valve (MV) is located between the Left Atrium (LA) and the Left Ventricle (LV) of the human heart and is typically composed of the Mitral Annulus (MA), two leaflets, chordae tendineae ("chordae"), two papillary muscles and the left ventricular myocardium. The mitral annulus is subdivided into anterior and posterior portions.

When the mitral valve is closed, the respective anterior and posterior leaflets come into close contact to form a single area of apposition. As will be understood by those skilled in the art, normal MV function involves proper force balancing, with each component working in concert during the cardiac cycle. Pathological changes affecting any component of MV, such as chordal rupture, annular dilation, papillary muscle displacement, leaflet calcification, and myxoma disease, can lead to altered MV function and cause Mitral Regurgitation (MR).

Mitral regurgitation is a dysfunction of MVs that causes blood to leak from the LV abnormality back into the left atrium during systole (i.e., the phase of cardiac cycle expulsion where blood moves from the LV into the aorta).

Current treatments for MV disease include surgical repair and replacement of MV, and more recently transcatheter repair and replacement of MV.

Challenges seen by effective MV replacement devices generally include operational delivery challenges; positioning and fixation challenges; sealing and paravalvular leakage challenges; and hemodynamic functional challenges such as Left Ventricular Outflow Tract (LVOT) occlusion.

With respect to the perceived operational delivery challenges, because conventional mitral valve prostheses are larger than conventional aortic prostheses, it is more difficult to fold and compress the larger mitral valve prosthesis into a catheter for deployment and retrieval by conventional trans-tip or trans-femoral delivery techniques.

Turning to the positioning and implantation challenges, instability and migration are the most significant obstacles given that the mitral valve is subject to high and repetitive loads in the case of high transvalvular pressure gradients and dynamic motion of the beating heart in the cardiac cycle.

With respect to sealing and paravalvular leakage, since the mitral annulus is large, it is desirable that the fit between the native annulus and the prosthesis be good with minimal paravalvular leakage. Generally, a prosthetic mitral valve may have a large, overhanging atrial portion or flare (flare) that may prevent leakage, but it also requires a large valve size at the ventricular level so that the prosthesis can fit tightly in the native MV. Conventionally, prosthetic mitral valves are smaller than diseased native valves, and additional material is added around the prosthetic valve to compensate for the large native mitral annulus. Undesirably, adding more material to the prosthetic valve increases the size of the delivery system and may cause valve thrombosis.

Some of the current transcatheter delivery systems utilize the folded structure of the replacement valve stent to capture and grasp the native leaflets and annulus, thereby anchoring the replacement valve. Such methods often suffer from device dislodgement-instability and/or migration of the implant due to insufficient interaction force between the implant and the native tissue, or excessive interaction force resulting in damage (e.g., tearing) and/or remodeling (e.g., elongation, reshaping) of the native tissue.

Finally, with respect to preservation of hemodynamic function, operational positioning of a conventionally large prosthetic mitral valve device as described above should not occlude the LVOT at the anterior portion of the mitral annulus and should not interfere with the native aorta and/or the associated structures of the mitral valve.

Accordingly, a heart valve leaflet replacement device and delivery and implantation system that do not suffer from the disadvantages and drawbacks of the current systems would be beneficial. It is desirable to secure a prosthetic mitral valve replacement system to the native mitral annulus. It is also desirable to improve the positioning of the mitral valve prosthesis, avoid LVOT obstruction, and prevent blood leakage between the mitral valve prosthesis and native MV. Furthermore, other desirable features and characteristics will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and the foregoing technical field and background.

Disclosure of Invention

Described herein are heart valve leaflet replacement systems that include a heart valve leaflet replacement device (e.g., a prosthetic mitral valve replacement device) and a multi-stage multi-lumen (MSML) heart valve delivery and implantation system for guiding and securing the heart valve leaflet replacement device to one or more of the native valve annulus. In one aspect, an MSML heart valve delivery and implantation system may be configured to guide and secure a mitral valve replacement device to a native mitral valve annulus. In another aspect, the MSML heart valve delivery and implantation system may be configured to guide and secure a prosthetic tricuspid replacement device to the native tricuspid annulus. For clarity, it will be understood that the present disclosure will focus on the delivery and implantation of valve leaflet replacement devices for treating functional and degenerative mitral regurgitation, however, it is contemplated that the valve leaflet replacement devices, MSML delivery and implantation systems and related methods may also be used or otherwise configured for treating other valve disease conditions and replacing other valves of the human heart, or may be used or otherwise configured for use in other mammals or animals suffering from valve defects.

In one aspect, a heart valve leaflet replacement system may include a heart valve leaflet replacement device, or prosthesis, that is configurable or otherwise sized to fit within an MSML delivery and implantation system and then selectively expanded to an operational size and position upon removal from the MSML delivery and implantation system within the heart. In other aspects, at least a portion of the prosthesis may include a stent having an upper atrial flare portion and a lower ventricular portion. In one aspect, the atrial flare may be configured to couple with a plurality of Dual Guide and Fixation (DGF) members to guide and fix the stent on the annulus, which may help prevent paravalvular leakage and prosthesis displacement after implantation. The lower ventricular portion of the prosthesis can displace a portion of the native leaflet out of the blood flow passage and house at least one prosthetic leaflet. In another aspect, a heart valve leaflet replacement device can include a lining skirt (lining skirt) that can be coupled to at least a portion of an inner surface and/or an outer surface of a stent. Optionally, the outer surface of the stent may be configured with additional skirt material to prevent paravalvular leakage. In one exemplary aspect, at least one prosthetic leaflet can be mounted on the inner lumen of the stent and/or on at least a portion of the outside of the stent that can function in place of at least one native leaflet to restore normal valve function, such as preventing mitral regurgitation.

In an exemplary embodiment, the MSML delivery system may be configured to implant the heart valve leaflet replacement system in a two-step procedure. In step 1, a plurality of DGF members are implanted into the native annulus of a diseased valve. In step 2, a prosthetic heart valve leaflet replacement device is implanted and secured in place at the implanted DGF member.

It should be apparent to one of ordinary skill in the art that various other prosthetic valve replacement devices, whether they are half-valves or whole-valves, circular or non-circular in shape, may be delivered and implanted using the MSML delivery methods described in the present disclosure.

In one aspect, delivery of the prosthesis may be performed using several desired delivery access (access) approaches, such as, for example, but not meant to be limited to, minimally invasive surgery, trans-septal, or trans-atrial approaches. In one exemplary aspect, the transseptal approach can include creating an opening in an internal jugular vein or femoral vein for subsequent minimally invasive delivery of a portion of a heart valve leaflet replacement device or prosthetic device through a superior vena cava or inferior vena cava flowing into the right atrium of the heart. In this exemplary aspect, the transseptal access path traverses the interatrial septum of the heart, and once complete, the components of the heart valve leaflet replacement device are operably positionable in the left atrium, native mitral valve, and left ventricle.

In one aspect, an MSML delivery and implantation system may include a primary docking/guidance system, a DGF member delivery system, and a valve containment, positioning, and locking system (VHPL).

In one exemplary aspect, the VHPL may include an introducer sheath, a plurality of locking catheters, a stent holder sheath, and a valve chamber sheath.

In one aspect, it is contemplated that the primary docking sheath may be placed within the access path to allow desired components of the heart valve leaflet replacement system to be operably positioned within the left atrium without complications.

In one aspect, a component of a heart valve leaflet replacement device can include a DGF member that can be operably positioned and implanted at a desired location in the native annulus prior to delivery of a prosthesis. In this aspect, the DGF member may guide the subsequent precise positioning and fixation of the prosthesis. In other aspects, the plurality of DGF members may help prevent blood leakage between the operatively positioned prosthesis and the native mitral annulus. In one aspect, the DGF member can be configured with a removable component that can help guide the heart valve leaflet replacement device to an operable position and then be removed from the patient's body after the prosthesis is secured, and a permanent component that remains in the patient's body to hold the heart valve leaflet replacement device secured to the native annulus.

In exemplary aspects, the DGF member may comprise a plurality of segments, such as a nose member, a body member, and a tail member. In one aspect, the DGF head member is operably insertable and embeddable in annular tissue. In one aspect, the DGF body member can be configured with a DGF locking member to secure the heart valve leaflet replacement device to the native mitral annulus. In another aspect, the DGF body member can be configured such that it can be engaged to a catheter, the DGF head member drilled into tissue, and disengaged from the catheter to leave the entire DGF member permanently implanted in the annulus. The DGF member is designed to be removable and repositionable. In one aspect, the DGF tail member may be configured as a flexible member extending from a proximal portion of the DGF body to a proximal end of the MSML system. Optionally, the DGF tail may be configured to be selectively removable such that it can be removed from the body at the completion of the heart valve leaflet replacement system implantation procedure.

As will be appreciated by those skilled in the art, during an operation, the patient's heart is beating and the annulus tissue is moving, so it may be difficult to: 1) Engaging annulus tissue; and 2) maintain proper positioning of the DGF delivery system throughout implantation of the DGF member. Under such conditions, it may be considered necessary to have a stabilizing member. In this aspect, the DGF head member may be configured with a stabilizer member, e.g., a concentric needle within the DGF head member, for stabilizing the DGF member and DGF member delivery mechanism during DGF member implantation. In one aspect, the stabilizer member may be configured with other mechanisms that may engage and/or disengage tissue, such as vacuum suction, a clamping and release mechanism, or other mechanisms due to changes induced by electromagnetic or thermal fields.

In one aspect, a DGF body member can be configured with a prosthetic valve securing mechanism that includes a plurality of DGF locking members. In one aspect, the DGF locking member can be configured to engage the prosthetic valve to secure it in the operative position.

In an exemplary aspect, the DGF locking member may be configured to attach to the DGF body member via a flexible component.

The DGF locking member may be configured to engage the DGF tail member.

In one aspect, the prosthesis may be configured to engage the DGF locking member via a plurality of through holes in an atrial flare portion of the stent frame. In this aspect, the DGF tail member may be a tether configured such that one end of the tether is attached to the DGF body member and the other end of the tether can exit the body. The tether may then be inserted through an aperture in the atrial flare of the stent so that the prosthesis may be delivered over the DGF tail member and the atrial flare of the stent may be accurately delivered to the DGF body member embedded in the annulus.

In one aspect, the positioning of such DGF members is not random. The spacing of the DGF members on the annulus should closely match the spacing of the through holes on the prosthetic stent to ensure accurate positioning and placement of the prosthesis within the posterior annulus.

Alternatively, two sets of DGF members may be deployed separately. In this aspect, an initial set of DGF members may be implanted near the commissures of the native valve and in the middle of the posterior annulus. The set of DGF members will guide the precise positioning and deployment of the prosthesis. After valve deployment, a second set of DGF members may be implanted directly on top of the deployed prosthesis. In another aspect, a second set of DGF members may be deployed on top of the flared section of the prosthetic stent. The skilled artisan will appreciate that in the case of an additional DGF member implanted in the annulus, the gap between the prosthesis and the native annulus is smaller, thereby preventing paravalvular leakage and ultimately rupture of the prosthetic valve.

In one aspect, the DGF locking member may be configured such that it can be selectively compressed to a diameter smaller than the diameter of the aperture on the atrial flare portion of the stent such that it can pass through the aperture and then selectively re-expanded to its original size greater than the diameter of the aperture on the flare portion of the stent to prevent reverse movement of the DGF locking member through the aperture.

In one exemplary aspect, the DGF locking member may be configured with a plurality of radially compressible legs, e.g., forming a conical shape, wherein a proximal tip of the conical shape has a smaller diameter than the aperture on the atrial flare of the stent and a distal base of the conical shape has a larger diameter than the aperture on the atrial flare of the stent. In operation, the DGF tail may be tensioned to pull the proximal tip of the DGF locking member into the hole on the atrial flare of the stent and, upon contact of the locking member legs with the edges of the hole, will compress radially to allow the DGF locking member to be pulled completely through the hole. After the locking member has fully passed through the stent, the DGF locking member legs may be re-expanded to full size to prevent reverse movement of the DGF locking member through the holes in the atrial stent flares.

In one aspect, the VHPL system may include an introducer sheath that fits within the lumen of the docking sheath and may house all other VHPL system components. In one exemplary aspect, the introducer sheath may be configured with a divider at the distal tip that organizes all of the inner tubing and prevents the DGF tail and locking catheter from tangling or overlapping.

In another aspect, the entire introducer sheath may be configured with multiple lumens to organize the inner tubes. In one exemplary aspect, the divider may have four chambers: a central chamber surrounded by three outer chambers. A stent holder sheath may pass through the central lumen of the divider and a locking catheter may pass through each of the three outer lumens.

In one aspect, VHPL may comprise a valve chamber. In this aspect, the heart valve leaflet replacement device can be crimped down to fit within a valve chamber on the distal end of the VHPL system, and then selectively expanded to an operative size and positioned after removal from the valve chamber in the VHPL system.

In one aspect, the stent holder can be configured to fit within a lumen of a valve chamber and facilitate release of the prosthetic valve. In this aspect, the stent holder may be configured to attach to a distal tip of a stent holder sheath extending to a proximal side of the VHPL system such that a position of the stent holder within the valve chamber may be controlled by manipulating the stent holder sheath on the proximal side of the VHPL system.

In one aspect, the valve chamber sheath can be configured to be steerable or non-steerable to fit within the lumen of the stent holder sheath. The valve chamber sheath may optionally be configured as a tube or solid rod.

In an exemplary aspect, the stent may be crimped over a stent holder sheath proximal to the stent holder and loaded into the valve chamber. The prosthesis may then be subsequently released from the valve chamber by distally advancing the valve chamber sheath while keeping the stent holder position fixed. The stent holder will prevent distal movement of the prosthesis, whereas when the valve chamber is moved distally, the prosthetic valve will be released from the valve chamber-starting proximally of the prosthetic valve and ending distally of the prosthetic valve.

In one exemplary aspect, three DGF head members may be implanted first in the annulus: one at the medial commissure, one at the lateral commissure, and one in the center of the posterior annulus. The slits on the valve chamber will align with the holes on the medial, lateral and central edges of the atrial flare portion of the crimped prosthetic valve, respectively, so that the trailing (trailing) DGF tail can be easily fed through (fed through) the corresponding atrial flare orifice and then through the corresponding locking catheter in the valve containment, positioning and locking system.

In one aspect, the VHPL system may be inserted into the body of a patient, and the DGF tail may be tensioned to guide the valve chamber, and thus the prosthetic valve, to an operational position at the previously implanted DGF cephalic member. After being in place at the mitral annulus, the valve chamber sheath can be advanced to begin releasing the prosthetic valve at the atrial flare and continue until the entire ventricular portion of the prosthetic valve has been released.

In one aspect, to obtain better positioning of the heart valve leaflet replacement system, one or more sheaths within the MSML delivery system may be configured to be deflectable and/or steerable. Further in this aspect, it is contemplated that the heart valve leaflet replacement system can be implanted in the mitral annulus by a transfemoral, transseptal procedure. In this way, the docking sheath may be inserted into the femoral vein, advanced into the inferior vena cava, and then may be engaged to bend the distal tip from the inferior vena cava through the septal puncture site at the fossa ovalis to gain access to the left atrium. The VHPL system may be inserted through the docking sheath and advanced to the left atrium. The stent holder and valve chamber sheath may be advanced, and the stent holder sheath may be engaged to bend the stent holder sheath tip toward the left ventricle and position the valve chamber in the center of the mitral annulus orifice.

In one aspect, the prosthesis can be secured in place at one or more implanted DGF cephalad members by tensioning the respective DGF tails and engaging the corresponding DGF locking devices with the prosthesis before fully releasing the crimped prosthesis from the valve chamber.

In one aspect, the VHPL system can be configured with a suture tensioning mechanism operable to individually tension the DGF tails, or optionally simultaneously tension multiple DGF tails, to guide the positioning and locking of the heart valve replacement system.

In one aspect, after valve deployment, a plurality of locking catheters may be advanced distally against the atrial flare of the stent while tensioning the DGF tail to engage the DGF locking mechanism with the prosthesis.

In one aspect, the locking catheter is configured to be flexible and can be bent with other steerable sheaths during prosthesis locking. In another aspect, the inner diameter of the distal tip of the locking catheter is larger than the DGF locking member so that they can pass over the DGF locking member. In this aspect, the locking catheter will be pushed against the atrial flare portion of the prosthesis until the DGF locking member is pulled through the atrial flare opening.

In one aspect, the lower ventricular portion of the stent may be configured with a mechanism that selectively engages the VHPL system such that the prosthesis can be guided, positioned, and secured in place in a highly controlled manner. In one exemplary aspect, the stent holder may be configured with a recess having a shape complementary to a projection on the lower ventricular portion of the stent frame such that the projection fits within the recess of the stent holder and the recess acts to hold the projection of the stent frame against the valve chamber inner wall until the valve chamber is advanced distally sufficiently to expose the projection recess.

In one aspect, the lower ventricular part of the stent frame may be configured with a protrusion on the tip of the extension member that is longer than the rest of the stent, such that the protrusion is the lowest point of the stent when in operation. In one exemplary aspect, the stent frame may be configured to resemble a stingray in shape, wherein the extension member resembles a stingray tail that may extend longer than the main body of the stent frame, and the tip of the extension member may be configured to engage with the stent holder. Alternatively, the lower ventricular portion of the stent frame may be configured with a plurality of projections or holes, or other engagement members, on the tips of a plurality of extension members that are longer than the remainder of the stent. The engagement member is operably engageable with a complementary engagement member, such as a recess or projection on a stent holder or stent holder sheath.

In an optional aspect, the prosthesis may be released from the valve chamber leaving only the extension member projections engaged in the stent holder so that the prosthesis may be fully expanded in the mitral annulus. The locking catheter can be advanced and the DGF tail can be tensioned to lock the prosthesis in place at the implanted DGF member while keeping the stent tabs engaged in the stent holder. One skilled in the art will appreciate that once the prosthesis is released, blood pressure in the left ventricle may cause the prosthesis to undesirably migrate without a mechanism to hold the prosthesis in place. By including a mechanism to constrain the prosthesis in the valve chamber until the prosthesis is secured by the DGF locking member, the safety of the delivery and implantation process is greatly improved. This mechanism may be accomplished by a variety of different engagement members that may engage and disengage the prosthetic valve device from portions of the VHPL system during deployment of the prosthetic valve.

In one aspect, it is contemplated that after deployment of the prosthetic valve and DGF locking members, if there is any paravalvular leak or instability of the valve in the operative position, a plurality of additional DGF members may be deployed atop the prosthetic leaflet device using the DGF delivery system such that each DGF head member of the additional DGF members is driven through the skirt material on the atrial flare portion of the prosthesis and embedded in the muscle annulus tissue until the body portion of the DGF body member is flush with the atrial flare portion of the prosthesis. In this aspect, no additional securing mechanism, i.e., locking member, is required on the DGF body member.

It is contemplated that after implantation of the heart valve leaflet replacement system, all components of the MSML delivery system may be removed and a septum closure device may be inserted through the docking sheath to close the ostium on the atrial septum. The entire MSML delivery system may then be removed from the body.

The various embodiments described in this disclosure may include additional systems, methods, features and advantages that are not necessarily expressly disclosed herein but will be apparent to one of ordinary skill in the art upon examination of the following detailed description and accompanying drawings. It is intended that all such systems, methods, features and advantages be included within this disclosure and be protected by the accompanying claims.

Drawings

A better understanding of the features and advantages of the present subject matter will be obtained by reference to the following detailed description that sets forth illustrative embodiments, in conjunction with the accompanying drawings. The features and components of the following drawings are illustrated to emphasize the general principles of the disclosure. Corresponding features and components may be designated by matching reference characters throughout the drawings for consistency and clarity.

Fig. 1A-1D illustrate various schematic views of a prosthetic valve. Fig. 1A illustrates a front view of a stent frame of a prosthetic valve showing an atrial flare portion featuring a plurality of through holes, and a lower ventricular portion featuring an elongated member with projections. Fig. 1B illustrates a side view of a stent frame of a prosthetic valve. Fig. 1C illustrates an anterior view of a prosthetic valve showing three leaflets. Fig. 1D illustrates a side view of a leaflet attached to a prosthetic valve stent, showing the prong structure of the middle leaflet attached to the inner stent surface.

Fig. 2A-2C show exemplary aspects of a DGF member. FIG. 2A illustrates the components of a DGF member. Fig. 2B illustrates a top view of a DGF head member. FIG. 2C illustrates a DGF locking member and its components.

Fig. 3A and 3B are schematic views of a stent held in place by a plurality of DGF members. Fig. 3A is a side view showing the atrial flare portion of the stent sandwiched between the DGF head and the DGF locking member. Fig. 3B illustrates the location of three DGF members along the flared portion of the prosthetic valve stent.

Fig. 4 is a schematic diagram depicting one aspect of an additional DGF member, without a DGF locking member, implanted in the atrial flare portion of the stent.

Fig. 5 is a schematic view of the docking system and valve containment, positioning and locking system mounted on an angled base.

FIG. 6 is a schematic view of a valve containment, positioning and locking system catheter with the valve chamber attached to the distal section, followed by a stent holder mounted on a steerable stent holder sheath, and a plurality of locking catheters; all residing within the guide sheath and separated by a divider.

Fig. 7 is a perspective view of a valve chamber attached to the distal end of a valve chamber sheath.

Fig. 8A-8D illustrate a heart valve leaflet replacement system and steps for loading, releasing and locking a prosthetic valve. Fig. 8A shows the prosthetic valve (only the stent is shown for visual clarity) loaded into the valve chamber. Fig. 8B shows the release of the prosthetic valve by distally advancing the valve chamber. Fig. 8C shows the prosthetic valve stabilized in the valve chamber during locking by the mechanism, and the locking catheter is guided by the DGF member tail (not shown) to the DGF member (not shown) on the prosthetic valve flared section and locks the prosthetic valve in place. Fig. 8D shows the prosthesis being secured at the first three DGF members, and the entire valve containment, positioning and locking system can be removed.

Detailed Description

The present invention may be understood more readily by reference to the following detailed description, examples, drawings, and claims, and their previous and following description. However, before the present devices, systems, and/or methods are disclosed and described, it is to be understood that this invention is not limited to the specific devices, systems, and/or methods disclosed unless otherwise specified, as such can, of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing particular aspects only and is not intended to be limiting.

The following description is provided as an example of the ability to teach the apparatus, system, and method. To this end, those skilled in the relevant art will recognize and appreciate that many changes can be made to the various aspects described herein, while still obtaining the beneficial results of the present invention. It will also be apparent that some of the desired benefits of the embodiments of the inventions herein can be obtained by selecting some of the features without utilizing other features.

Thus, those who work in the art will recognize that many modifications and adaptations are possible and can even be desirable in certain circumstances and are a part of the present invention. Accordingly, the following description is provided as illustrative of the principles of the present invention and not in limitation thereof.

For clarity, it will be understood that the present disclosure will focus on the treatment of functional mitral regurgitation; however, it is contemplated that the heart valve leaflet replacement system and related methods can also be used or otherwise configured for treating other types of mitral regurgitation or replacing other diseased valves of the human heart, such as the tricuspid valve, or can also be used or otherwise configured for other mammals that also have valve defects.

As used throughout, the singular forms "a", "an" and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to "a leaflet" can include two or more such leaflets, unless the context indicates otherwise.

Ranges may be expressed herein as from "about" one particular value, and/or to "about" another particular value. When such a range is expressed, another aspect includes from the one particular value and/or to the other particular value. Similarly, when values are expressed as approximations, by use of the antecedent "about," it will be understood that the particular value forms another aspect. It will be further understood that the endpoints of each of the ranges are significant both in relation to the other endpoint, and independently of the other endpoint.

As used herein, the term "optional" or "optionally" means that the subsequently described event or circumstance can or cannot occur, and that the description includes instances where said event or circumstance occurs and instances where it does not.

The word "or" as used herein means any one member of a particular list and also includes any combination of members of that list. Furthermore, it should be noted that conditional language, such as "can," "might," or "might," unless expressly stated otherwise or understood otherwise in the context of usage, is generally intended to convey that certain aspects include certain functions, elements, and/or steps, while others do not. Thus, such conditional language is not generally intended to imply that features, elements, and/or steps are in any way required for one or more particular aspects or that one or more particular aspects necessarily include logic for determining (with or without author input or prompting) whether such features, elements, and/or steps are included or are to be performed in any particular embodiment.

Components are disclosed that can be used to perform the disclosed methods and systems. These and other features are disclosed herein, and it is understood that when combinations, subsets, interactions, groups, etc. of these features are disclosed that while specific reference of each various individual and collective combinations and permutation of these may not be explicitly disclosed, each is specifically contemplated and described herein for all methods and systems. This applies to all aspects of the present application including, but not limited to, steps in the disclosed methods. Thus, if there are a plurality of additional steps that can be performed it is understood that each of these additional steps can be performed with any specific embodiment or combination of embodiments of the disclosed methods.

The present method and system may be understood more readily by reference to the following detailed description of preferred embodiments.

Throughout the description, the terms "prosthetic valve" and "prosthesis" and "valve stent" and "heart valve leaflet replacement device" and "valve device" are used interchangeably and are considered as the heart valve replacement devices described herein.

Throughout the description, the terms "distal" and "proximal" are expressed with respect to an operator during use of the delivery system. The "distal" indicating device portion is distal, or in a direction away from the operator, while the "proximal" indicating device portion is closer, or in a direction toward the operator.

One skilled in the art can appreciate the complexity of transcatheter methods and systems for successfully deploying a prosthetic valve into the heart. Such a method involves a number of components and a number of steps. Although these components and steps are described in various parts of the description, it should be understood that these components and steps do not necessarily need to be used and performed in the order described herein in the description.

The heart valve replacement systems described herein may be used in conjunction with any heart valve replacement device or prosthesis. It is contemplated that the heart valve replacement system described herein comprises a series of systems that can be used simultaneously to deliver the prosthetic valve 2 into the heart of a subject.

In one aspect, the heart valve replacement system includes a multi-stage multi-lumen (MSML) delivery system that may be configured to deliver a heart valve replacement device or prosthesis 2 to an implantation site or native mitral annulus. Such systems may include Dual Guidance and Fixation (DGF) delivery systems and valve containment, positioning and locking (VHPL) systems. In one aspect, the DGF delivery systems described herein are configured to implant multiple DGF members in the native annulus and to help guide and secure the prosthetic valve to a targeted implantation location. In one aspect, the novel VHPL system may be configured to house and organize a plurality of DGF member tail, crimped prosthetic valves, and may be designed to progressively release the crimped prosthetic valves and secure the prosthetic valves at the implanted DGF members via DGF body securing mechanisms.

In one aspect, the MSML delivery system may access the mitral valve: via the inferior vena cava, into the right atrium, across the interatrial septum to the left atrium, and then down to the native mitral annulus. It is contemplated that the MSML delivery system may also navigate to the implant site via the superior vena cava and follow the same previously described path toward the native mitral annulus.

Referring to fig. 1A-1D, in one aspect, a crescent-shaped stent 3 of an MSML delivery system may include an atrial flare portion 4, a ventricular portion 5, and a neck portion 6. In one aspect, the atrial flare 4, ventricular portion 5 and neck portion 6 are continuously attached to form a single body. At least portions of the atrial flare 4 and/or portions of the ventricular portion 5 may be formed to be self-expandable or balloon expandable to a desired operating position. In this aspect, it is contemplated that the stent 3 can be conventionally laser cut or braided into a desired shape, which can be radially collapsible and expandable. Thus, it is further contemplated that the stent 3 may comprise a plurality of components operatively connected to form an expandable mesh or non-mesh body, which may be made of: metallic or polymeric materials or bio-made materials including but not limited to cobalt chrome, stainless steel; or metals with inherent shape memory properties, including but not limited to nitinol. Optionally, it is contemplated that the scaffold 3 may include a plurality of vertical rigid structures connected by compliant materials such as biological tissue, synthetic materials such as polymers, and the like. The stent 3 can be configured to allow natural dynamic motion of any remaining native leaflet(s) to coapt with the prosthetic leaflet(s) 10.

In one aspect, it is contemplated that the atrial flare 4 of the stent 3 may be configured to be positioned on and/or over the native annulus when implanted. In this aspect, the atrial flare 4 of the stent 3 may be configured to facilitate fixation and sealing of the prosthesis 2, which may help prevent paravalvular leakage and post-implantation displacement. The mitral annulus is asymmetrical. The atrial flare 4 of the prosthesis 2 may be configured to cover or overlay the posterior aspect of the mitral annulus, which is divided into three leaflets, i.e., P1, P2 and P3. In one aspect, the flaring atrial portion 41 may span both commissures, i.e., the AC-anterior commissure and the PC-posterior commissure. In another aspect, the flared atrial portion 4 may include an anterior flared atrial portion and a posterior flared atrial portion such that when operably positioned it covers the entire circumference of the mitral valve.

In one aspect, as depicted in FIGS. 1A-1B, at least a portion of the atrial flare 4 has a bend 14. In this aspect, the bend may be an upward bow away from the heart chamber wall to prevent over-expansion of the heart chamber, which may result in deep penetration of the heart tissue. In other aspects, the upward buckling portion is oriented between about ninety degrees and one hundred twenty degrees (90-120 °) from the atrial flare 4. In other aspects, the bend 14 is only at the cell strut of the atrial flare 4, and therefore does not interfere with or distort the circular shape of the through hole 9 in the atrial flare 4.

On the other hand, at least part of the atrial flare 4 is configured with a plurality of through holes 9 to selectively engage the DGF member 101. On the one hand, the through-holes 9 may be designed with a circular shape, connecting the cell pillars and forming a bridge connection with the adjacent cells. A through hole 9 may be designed at each bridge junction of the atrial flare 4. On the other hand, the through-holes 9 may be designed at a position less than the total number of bridge connections of the atrial flare 4.

In one aspect, the entire circumference of the ventricular part 5 of the stent may be curved towards the left ventricular wall. Referring to fig. 1B, the bend angle 15 may be between sixty degrees and one hundred twenty degrees (60-120 °) relative to the atrial flare 4 of the stent 3.

Referring to fig. 1A and 1B, on the one hand, the bracket 3 is configured with an extension member 7. On the one hand, the extension member 7 may be configured as a straight section. On the other hand, the extension member 7 may be configured with a short extension length and a projection 8 continuously connected with the straight section at the distal end.

On the one hand, the protrusion 8 may be configured to have a larger width than the rest of the extension member 7.

In exemplary aspects, the at least one extension member 7 may be designed at the center of the distal portion of the ventricular part 5 of the stent. In this aspect, in the operative position, the extension member 7 is the longest section of the stent 3 that extends furthest into the left ventricle. In this aspect, the extension member 7 is about 2 to 7 millimeters (2 to 7 mm) longer than the rest of the stent 3.

In an exemplary aspect, and as depicted in fig. 1B, the extension member 7 may be configured to curve radially inward to avoid interfering with the posterior wall of the ventricle when in operation.

In optional aspects, the extension member 7 may be located at other sections along the circumference of the ventricular portion 5 of the stent. In an exemplary aspect, referring to fig. 1A, the extension member 7 may extend from one or more lower cells of the ventricular portion 5 of the stent 3.

Referring to fig. 1A, in one aspect, the projections 8 of the extension member 7 are configured to hold the prosthesis during release from the VHPL system to prevent it from migrating unintentionally before the DGF fixation mechanism can be engaged. In this aspect, the (VHPL) system 1 is selectively designed to attach to the projection 8 of the extension member 7 until the prosthesis is secured to the targeted implant site. After the prosthesis 2 is fully secured in the implanted position, the projections 8 can be selectively released from the (VHPL) system 1 to disengage the prosthesis 2 from the (VHPL) system 1.

In one aspect, the projections 8 are configured with a dome, circular, square, rectangular, triangular, or irregular shape. On the other hand, the projection 8 is provided with at least one through hole.

In one aspect, as depicted in fig. 1C and 1D, at least one prosthetic leaflet 10 is mounted on an inner surface of the ventricular portion 5 of the stent 3. In other aspects, at least one prosthetic leaflet 10 of the plurality of prosthetic leaflets has a different shape. In another aspect, the at least one prong structure 11 of the at least one prosthetic leaflet 10 comprises a plurality of prong structures 11. It is contemplated that at least one prong structure 11 is coupled to the leaflet free edge.

In one aspect of the MSML delivery system, the prosthetic leaflet 10 can be configured to resemble a native posterior mitral leaflet in shape.

It is contemplated that the at least one prosthetic leaflet 10 and the at least one prong structure 11 can be configured from a single, flat, flexible material, such as biological tissue, a polymeric material, or a piece of fabric, and can be attached to the stent 3 in such a way that it creates a 3D dome-like structure that bulges radially inward from the stent attachment point. The prosthetic leaflet 10 can be configured to be movable during a cardiac cycle, wherein the prosthetic leaflet 10 moves closer to the inner surface of the stent during diastole and moves further from the inner surface of the stent during systole.

Referring to fig. 1C, in one aspect, the at least one prosthetic leaflet 10 can comprise three leaflets: two smaller lateral leaflets and one large central leaflet, which form three distinct dome-like structures extending radially from the inner surface of the ventricular portion 5 of the stent 3. In this aspect, the three leaflets may be configured to span the circumference of the lower ventricular portion of the stent. The prosthetic leaflets 10 can be tightly fitted together on the inner surface of the stent 3 to prevent transvalve leakage during operation. Further, in this aspect, the leaflets may be configured to bulge radially inward from the stent 3 such that they are positioned in the blood flow trajectory when in operation and may close the mitral valve orifice under systolic blood pressure.

In one exemplary aspect, as shown in fig. 1C-1D, the smaller lateral leaflets can be asymmetric, with shorter lengths on the lateral edges corresponding to the shape of the lower ventricular portion 5 of the stent 3. In one aspect, the larger central leaflet may have a symmetrical shape and two prong structures 11 extending from the free edge of the leaflet. Furthermore, in this aspect, the free ends of the prongs 11 may be attached to portions of the support 3, for example by sewing the ends of the prongs 11 to the support via through holes 12 in the lower ventricular portion 5 of the support 3. In this aspect, the prong structure 11 prevents excessive bulging and prolapse of the large central leaflet and also helps to distribute stresses evenly in the prosthetic leaflet 10, which is important for durability. Optionally, one or more prong structures 11 may be added to the lateral leaflets.

Referring to fig. 5, the msml delivery and implantation system may include a docking system 326, a DGF member delivery system, and a VHPL system 1, which may be mounted on a handle platform 301 to facilitate the delivery process. The handle platform 301 is mounted on the base 324.

In one aspect, the base 324 features a mechanism that: it allows angular adjustment of the MSML system to optimally access the body's access site. The base 324 may be made of, but is not limited to, a rigid material such as metal, plastic, and other similar materials.

In one aspect, the docking system 326 includes a docking sheath 327 and a docking handle. The docking sheath 327 may be first passed through an introducer sheath into the body. In one exemplary aspect, the docking sheath 327 may be configured to be deflectable in order to access the implant site. In this aspect, the distal end of the docking sheath 327 may be configured to bend up to one hundred eighty degrees (180 °) relative to the proximal end of the sheath.

After the docking system 326 is in place, the DGF system can be piloted. In this aspect, multiple DGF members 101 (e.g., as shown in fig. 2) may be delivered and implanted at desired locations on the annulus, either sequentially or simultaneously.

In other aspects, it is contemplated that the method of implanting the DGF member 101 can be performed prior to delivery of the prosthesis 2.

Referring to fig. 2A, in one aspect, DGF member 101 may comprise a DGF head member 102, a DGF body member 103, a DGF locking member 105, and a tether 114, which is intended to be permanently implanted in the mitral annulus.

On the other hand, after delivery and fixation of the prosthesis 2, implantation of additional DGF members 101A may be performed. In this aspect, the DGF member 101A may be configured with a DGF head member 102, a DGF body member 103, and a DGF tether 114 forming a loop.

In one aspect, as shown in fig. 2B, the DGF member 101 is configured with: a head portion 102 that engages tissue on or around the annulus; and a body portion 103 having an adapter 109 that engages the DGF delivery conduit.

It is also contemplated that the DGF head member 102 may be configured to be implanted into the native annulus tissue and resist separation after implantation. In exemplary aspects, the DGF head member 102 may have, but is not limited to, a helical shape, a coil shape, a fork shape, a screw shape, and a barbed hook shape that engages the annulus tissue. The DGF nose member 102 may be formed from, but is not limited to, nitinol, stainless steel, cobalt chromium alloys, polymers, and the like.

In one exemplary aspect, the DGF head member 102 is configured with a coil 108, the coil 108 having a length of between about four and ten millimeters (4-10 mm) and a diameter of between about two and five millimeters (2-5 mm), formed from wire having a diameter of between 0.25 and one millimeter (0.25-1.0 mm).

In one aspect, the DGF head member 102 can be configured with a stabilizing member 111 to facilitate controlled implantation of the DGF head member 102 into the annulus tissue via a DGF delivery system when in operation. In one exemplary aspect, the stabilizing member 111 is configured as a straight wire having a diameter of between about 0.25 and one millimeter (0.25-1.0 mm) extending axially through the center of the spiral, the straight wire having a sharp tip extending beyond the end of the spiral by between about one and three millimeters (1-3 mm). In other aspects, the stabilizing member 111 may be configured as a needle with a sharp distal tip 112, the distal tip 112 extending axially about one to five millimeters (1-5 mm) beyond the DGF head member coil 108. In operation, the stabilizing member 111 can be used to engage the annulus tissue prior to screwing the DGF head member 102 into the tissue, which will help prevent unwanted movement of the DGF delivery system so the DGF head member 102 can be easily implanted at a desired location along the annulus. It will be appreciated that such a stabilizing member 111 can be used to engage tissue with the DGF member at a preferred implantation site and prevent the DGF member from moving from the target position during implantation.

In other aspects, the tip 119 of the coil 108 of the DGF head member 102, as exemplified in fig. 2A, may be shaped and configured to facilitate easy penetration into the annulus tissue. In one exemplary aspect, the tip 119 of the coil 108 is sharp and bent to the same pitch as the rest of the coil 108. In another exemplary aspect, the tip 119 can be straight. In another optional aspect, the tip 119 can have an arc length of between about one and three millimeters (1-3 mm).

In another aspect, as shown in fig. 2B, the DGF body member 103 includes a base and an extruded section 109 configured to engage a DGF delivery conduit. In this aspect, the base and the extruded section may be one piece. In other aspects, the extruded section 109 has a smaller dimension than the outer diameter of the base such that a DGF delivery catheter can be engaged therewith.

In one aspect, the extrusion section 109 includes three through holes, wherein two of the holes 110 are configured for attaching the DGF locking member 105 via the tether 114. In this aspect, the distal sections of the tethers 114 are secured to the DGF body via the two attachment holes 110, the intermediate portions of the tethers 114 are configured to be looped through the DGF locking members 105 in a manner that constrains the DGF locking members 105 from moving along the tethers 114, and the proximal sections of the tethers 114 that are proximal to the DGF locking members 105 are configured with loops.

In one aspect, a DGF body member 103 comprising a DGF locking member is configured to attach the DGF tail member 104 via a loop proximal of the tether 114.

In one aspect, the tether 114 may be straight, curvilinear, single or double or multiple lines.

In one aspect, the distance between the DGF body member 103 and the DGF locking member 105 may be between about 0.4 and one millimeter (0.4-1.0 mm) so that the atrial flare 4 of the stent 3 may fit tightly between the DGF body member 103 and the DGF locking member 105 in the operating position. Optionally, each DGF body member 103 may include a plurality of DGF lock members 105, wherein the spacing between adjacent DGF lock members 105 may be between about 0.4 and two millimeters (0.4-2.0 mm). The DGF body member 103 and DGF locking member 105 may be spaced apart on the tether 114 by tying a plurality of knots on the tether 114, for example. In other aspects, if the tether 114 is made of metal or plastic, the like, small protrusions may be welded, molded, or attached to the flexible member to maintain spacing.

In one aspect, it is contemplated that the tether 114 containing the DGF locking member 105 can be formed from a suture, rope, wire, or tether made of a polymeric material.

With reference to fig. 2A, it is contemplated that the DGF head member 103 and DGF body member 103 may be formed as a single component, or optionally by joining different parts by one or more of welding, bonding, adhesives or the like that are resistant to separation during in vivo loading. Further, in this aspect, the DGF head member 103 and DGF body member 103 may be formed of a strong and biocompatible material such that they may be permanently implanted in the human body and resist damage, such as, but not limited to, stainless steel, cobalt-chromium alloys, nitinol, non-absorbable polymers, biomaterials, and the like.

In one exemplary aspect, it is contemplated that the DGF locking member 105 may be configured to allow a portion of the atrial flare 4 of the stent 3 guided by the DGF tail member 104 to pass in only one direction and resist subsequent movement of the atrial flare 4 of the stent 3 in the opposite direction.

In one aspect, the DGF locking member 105 may be configured such that it may be selectively compressed to a diameter smaller than the diameter of the through-hole 9 on the atrial flare 4 of the stent 3 such that it may pass through the hole, and then selectively re-expanded to its original size greater than the diameter of the through-hole 9 to prevent reverse movement of the DGF locking member 105 through the hole.

In one exemplary aspect, referring to fig. 2c, the dgf locking member 105 may be configured with a proximal 107 portion and a distal 106 portion. In one aspect, the locking member 105 may have an overall length of between about 1.5 and 3.5 millimeters. The length of proximal portion 107 may be between about 0.5 and 1.5 millimeters. The length of the distal portion 106 may be between about one and two millimeters (1.0-2.0 mm).

In one aspect, the proximal portion 106 comprises a tubular shape having an outer diameter ranging between about 0.5 and 1.5 millimeters and an inner diameter ranging between about 0.4 and 1.2 millimeters. In one aspect, the distal portion 106 of the DGF member 101 includes a plurality of radially compressible legs that form a tapered shape in their original state. On the one hand, the outer diameter of the proximal portion of the locking member is smaller than the inner diameter of the through hole 9 on the atrial flared portion 4 of the stent 3. Further, in this aspect, the distal tip 107 of the DGF locking member 105 may be configured with a maximum fully expanded outer diameter that is larger than the inner diameter of the through hole 9 on the atrial flare 4 of the stent 3, so that it cannot pass through the through hole 9. The proximal 107 portion and the distal 106 portion of the DGF locking member 105 may be connected and continuous.

In operation, the DGF member tail 104 may be tensioned to pull the proximal portion 107 of the DGF locking member 105 into the through-hole 9 and when the distal portion 106 of the DGF locking member comes into contact with the edge of the through-hole 9, it will collapse radially such that its outer diameter is smaller than the inner diameter of the through-hole 9, which will allow the DGF locking member 105 to pass through the through-hole 9. After the DGF locking member 105 has completely passed through the through hole 9, the DGF distal portion 106 can re-expand to its original size to prevent reverse movement of the DGF locking member 105 through the through hole 9.

It is contemplated that the DGF locking member 105 may be manufactured, for example, by laser cutting a plurality of slits from a tube and then deforming the legs by bending them radially outward. In an exemplary embodiment, the slits may be between about 0.3 and 0.6 millimeters wide and between about 0.6 and 1.5 millimeters long. A heat treatment process may be performed to form the final flared cone geometry. The legs are designed so that they can be selectively compressed to pass through the through-hole 9 and then re-expand and return to their original shape after passing completely through the through-hole 9.

In one aspect, it is contemplated that the one or more DGF locking members 105 can be formed from, but not limited to, polymers, polytetrafluoroethylene (PTFE), stainless steel, nitinol and metal-like materials, or a combination of these materials.

In one aspect, the extruded section 109 of the DGF body member 103 may be configured as a protrusion shaped to fit closely into a complementary recess within the distal tip of the DGF delivery catheter such that when the protrusion is engaged with the distal DGF delivery catheter, rotation of the DGF delivery catheter in one direction will engage the DGF head member 102 with the tissue, while rotation of the DGF delivery catheter in the other direction will cause the DGF head member 102 to disengage from the tissue.

In an exemplary aspect, the extruded section 109 of the DGF body member 103, as shown in fig. 2B, can have a rounded rectangular shape that rises about 0.5 to two millimeters (0.5-2 mm) from the base of the DGF body member 103.

In one aspect, as shown in fig. 2A, a loop on the tether 114 may be configured to engage the DGF tail member 104. In one exemplary aspect, one end of the DGF member tail 104 may be inserted through a loop on the tether 114, while the two free ends of the DGF member tail 104 may extend through and out of the proximal side of the MSML delivery system.

In one aspect, a DGF component tail 104 connects the DGF delivery system and the VHPL system 1. In this aspect, the DGF member tail 104 acts as a bridging element to guide the VHPL system 1 from the access site to the implantation site.

In one aspect, it is contemplated that both free ends of the DGF member tail 104 may be inserted through the atrial flare opening 9 of the prosthesis 2 after deployment of the DGF member 101. In this way, both free ends of the DGF member tail 104 can also be inserted into the VHPL system 1 so that when the operator pulls the free end of the DGF member tail 104 away from the body, the DGF member tail 104 can be tensioned and guide the VHPL system components towards the DGF member 101 implanted in the annulus. Further tensioning of the DGF tail member 104 will help secure the prosthesis to the annulus via the DGF locking member 105 on the DGF member 101. After device implantation, the DGF member tail 104 may be removed from the VHPL system and body by pulling on one free end of the DGF member tail 104.

Alternatively, one end of the DGF tail member 104 may be tied to the loop and the other end may extend out of the body, proximal to the MSML delivery system. In this aspect, after the heart valve leaflet replacement device is implanted and secured in place, the trailing DGF tail can be cut by conventional cutting methods or by transcatheter suture cutting devices.

It is contemplated that DGF tail member 104 may be configured to fit within the inner conduit of the MSML delivery system and be long enough to extend from DGF body member 103 and away from the MSML delivery system. In this aspect, the DGF tail member 104 may have a diameter of about 0.1 to 0.5 millimeters, and may be at least about 2.5 meters in length.

Referring to fig. 3A, in one aspect, after implantation of the prosthesis 2, the atrial flare 4 of the prosthesis 2 will be sandwiched between the DGF locking member 105 and the DGF body member 103. It will be appreciated that the spacing between the DGF locking member 105 and the DGF body member 103 is optimised such that there is limited movement of the prosthesis 2 after implantation.

Referring to fig. 3B, in one aspect, at least three DGF members 101 are implanted, two of the DGF members 101 being implanted at lateral portions of the atrial flare 4 of the stent 3 and one being implanted at the center of the atrial flare 4 of the stent 3.

In one aspect of the method of using the MSML delivery system, at least three DGF members 101 are implanted in the annulus before the prosthesis 2 is implanted via the VHPL system 1. After implantation of the prosthesis 2, at least one additional DGF member 101A, without the DGF locking member 105, will be implanted over the atrial flare 4 of the prosthesis 2. The DGF member 101A may penetrate the skirt material of the prosthesis and anchor into the tissue. On the other hand, the DGF member 101A may be configured to pass through the through hole 9 of the atrial flare 4. Referring to fig. 4, as shown, three DGF members 101 may be implanted at the lateral sides (P1 and P3) of the atrial flare 4, and one DGF member 101 may be implanted at the center (P2) of the atrial flare 4. Additional DGF members 101A may be implanted between the DGF members 101 at the P1 and P2 positions and P2 and P3 positions. By implanting the additional DGF member 101A, as will be understood by those skilled in the art, paravalvular leakage between the prosthesis 2 and the annulus can be eliminated and displacement of the prosthesis 2 can be prevented, allowing for normal coaptation between the prosthetic and native leaflets.

For clarity, the following description outlines one exemplary VHPL system 1 design for successful delivery and fixation of a prosthesis. The shape and design of the outer compartment, configuration and assembly controlled by the VHPL system 1 may vary as long as they are capable of performing the same general function, i.e., translation or limited movement of the sheath, tensioning of the wire or tether, etc. Thus, the examples shown herein are for the purpose of better description and illustration, but are not limited to the specific design of any component.

Referring to fig. 6, in one aspect, a VHPL system 1 may include an outer sheath 306, the outer sheath 306 housing a plurality of conduits and tubes that function to deliver a prosthesis.

In one aspect, the outer sheath 306 may be a guide sheath. In this aspect, the guide sheath 306 may house the stent holder sheath 206 attached to the valve chamber 201, the valve chamber 201 housing the prosthetic valve in the crimped stage. In this aspect, the stent holder sheath 206 may deflect to guide and position the valve chamber 201 from the access site to the left ventricle. In this aspect, the valve chamber 201 is connected to a valve chamber sheath 203, and the valve chamber sheath 203 can slide along the lumen of the stent holder sheath 206. In this aspect, sliding of the valve lumen sheath 203 is the mechanism to release the prosthetic valve.

In one aspect, the outer sheath 306 can house a plurality of locking catheters 317. In this aspect, the locking catheter 317 and stent holder sheath 206 may be organized with a multi-lumen guiding sheath 306, all of which may be inserted into the body through a larger diameter docking sheath 327. In operation, by tracking along the DGF tail 104, the prosthetic valve 2 is guided to a plurality of previously implanted DGF members 101, the DGF tail 104 is loaded through the atrial flare opening 9 of the crimped prosthetic valve 2 and through a corresponding locking catheter 317 to the proximal end of the VHPL system 1.

In this aspect, the valve chamber sheath 203, the stent holder sheath 206, the locking catheter 317, and the guide sheath 306 are configured to move independently of the docking sheath 327 to obtain proper positioning. Further, the valve chamber sheath 203 and the stent holder sheath 206 are configured to move together and independently of the locking catheter 317 and the guide sheath 306. To deploy the valve 2, the valve chamber sheath 203 may be advanced relative to the stent holder sheath 206. To secure the prosthesis 2 in place, the DGF member tails 104 must be individually tensioned while each locking catheter 317 is advanced individually. After the prosthesis 2 is completely released and secured in place, all the sheaths can be retracted together out of the patient's body.

One skilled in the art can appreciate the need for a precise and stable valve release mechanism. Thus, the VHPL system may be mounted on a handle platform 301, for example, as shown in fig. 5. In the example shown, handle platform 301 is located on base 324, proximal to docking system 326. The outermost introducer sheath 306 and associated inner sheath on the handle platform 301 are inserted into the docking sheath 327. The handle platform 301 is configured such that it allows the introducer sheath 306, stent holder sheath 206, and valve chamber sheath 203 to simultaneously slide a specified distance along the base 324. In other aspects, the handle platform 301 is designed to prevent rotation of the introducer sheath 306 throughout the valve delivery process. The handle platform 301 may be made of any rigid and durable material such as metal, plastic, and the like.

In one aspect, the introducer sheath 306 is comprised of a distal portion and a proximal portion.

In one aspect, the distal portion of the introducer sheath 306 may be made of a composition of materials that are flexible and conform to the sharp curvature of the deployment paths in the natural heart chambers, one of the deployment paths including from the inferior vena cava to the septum; while the proximal portion of the guide sheath 306 may be made of a more rigid combination of materials than the distal portion in order to prevent buckling during delivery.

In one aspect, the distal end of the introducer sheath 306 may be configured with a divider 307. In this aspect, the divider 307 of the guide sheath 306 acts as a organizer to space the inner sheath within the guide sheath 306 to avoid entanglement throughout prosthetic valve delivery.

In one aspect, the divider 307 of the guide sheath 306 is a separate component secured to the distal portion of the guide sheath 306. In one aspect, divider 307 may be a cylindrical member having a plurality of cavities. In one aspect, the divider 307 may have a plurality of chambers, such as four chambers, with one central chamber and three outer chambers surrounding the central chamber. In this aspect, a central lumen housing the deflectable stent holder sheath 206 and three peripheral lumens housing the locking catheters 317. As the skilled artisan will appreciate, the divider 307 organizes the inner sheath within the guide sheath 306 to avoid entanglement throughout the delivery of the prosthetic valve 2.

In another optional aspect, the introducer sheath 306 may be configured as a multi-lumen tube throughout its entire length without the addition of a divider 307. In this aspect, the multi-lumen introducer sheath may have four lumens, one in the center and three in the periphery, and all of the lumens are separated by walls.

In one aspect, the stent holder sheath 206 can deflect and translate along the handle platform. In this aspect, the stent holder sheath 206 may be mounted on a

handle system

309, 301, the

handle system

309, 301 allowing an operator to deflect a distal portion of the stent holder sheath 206. In other aspects, the stent holder sheath 206 may be mounted on a slidable handle system.

Referring to fig. 6, in one aspect, the deflectable stent holder sheath 206 may be located at the central lumen of the guide sheath divider 307. In one aspect, the deflectable stent holder sheath 206 may be configured as a composite sheath that includes portions having varying stiffness and flexibility other significant characteristics, such as pushability and kink resistance. These characteristics allow the stent holder sheath 206 to deflect from 0 ° to 180 ° while maintaining its integrity and ability to deflect the sheath contained therein.

In one aspect, the deflectable stent holder sheath 206 may comprise three sections, a distal section, a middle section, and a proximal section. In this aspect, the distal section is a stiff straight section with the prosthetic valve 2 crimped thereon. The middle section of the deflectable stent holder sheath 206 is a soft coiled section that has the inherent ability to bend at a small radius (tip radius) without kinking or causing damage to any sheath residing therein. The proximal portion of the deflectable stent holder sheath 206 is a long stiff section that provides stability and stiffness across the entire VHPL 1. At least one pull wire is embedded within the wall of the deflectable stent holder sheath 206. By selectively tensioning at least one pulling wire, the deflection of the soft intermediate section can be controlled.

In this aspect, the stent holder 207 serves as a safety feature within the delivery system to maintain control and repositioning capabilities of the prosthetic valve before it is fully deployed and locked to the native mitral annulus. When the valve chamber 201 is translated distally past the stent holder 207, the protrusions 8 on the extension members 7 of the stent 3 are released from the stent holder 207, thereby fully releasing the prosthetic valve from the valve chamber 201.

In one aspect, the distal section of the VHPL system 1 may comprise a valve chamber 201 to house the prosthetic valve 2 within the VHPL system 1. In this aspect, the prosthetic valve 2 can be crimped down to fit within the valve chamber 201 on the distal end of VHPL 1, and then selectively expanded to an operative size and positioned once released from the valve chamber 201.

In one aspect, referring to fig. 7, the valve chamber 201 may comprise a cylindrical or conical shape that is closed on the distal end and has an inner diameter of about six to eight millimeters (6 to 8 mm), or is large enough to accommodate the crimped prosthetic valve 2, and an outer diameter of about seven to nine millimeters (7-9 mm), or is small enough to fit within the docking sheath. The length of the valve lumen can be configured to be greater than the length of the crimped prosthetic valve 2 so that it can accommodate the entire crimped prosthetic valve 2 inside. The valve chamber cavity can be about twenty to fifty millimeters (20-50 mm) in length.

In other aspects, the smaller diameter valve chamber sheath 203 may be configured to attach to a closed end on the distal end of the valve chamber 201, extending to the proximal side of the VHPL system 1, such that the valve chamber 201, and thus the position of the prosthetic valve 3 within the heart, may be controlled by manipulating the valve chamber sheath 203 on the proximal, i.e. operator, side of the VHPL system 1.

It is contemplated that the distal end 204 of the valve chamber and the cylindrical portion of the valve chamber 201 may be made from one solid piece of material, or optionally separate pieces of similar or different materials that are otherwise attached together. Referring to fig. 6, in an optional aspect, the distal end of the valve chamber 201 may be configured with: a central lumen to facilitate attachment with the valve chamber sheath 203; and rounded edges to prevent damage to surrounding tissue during operation.

The valve chamber sheath 203 can optionally be configured as a tube or solid rod. In one aspect, the valve chamber sheath 203 may be configured with multiple sections of varying stiffness along its length. Ideally, the valve lumen sheath 203 may be configured with: a rigid distal section within the valve chamber 201; followed by a compliant intermediate section to allow bending and facilitate steering of the VHPL system 1 within the patient; followed by another rigid section at the proximal end to provide pushability.

In one aspect, the stent holder 207 may be configured to fit within the lumen of the valve chamber 201 at the same outer diameter as the crimped prosthesis 2. The stent holder 207 may be configured to attach to the distal tip of a smaller diameter stent holder sheath 206 extending to the proximal side of the VHPL system 1, such that the position of the stent holder 207 within the valve chamber 201 may be controlled by manipulating the stent holder sheath 206 on the proximal side of the VHPL system 1.

In one aspect, in operation, the stent holder 207 may be positioned distal to the crimped prosthesis 2 within the valve chamber 201. Thus, the valve lumen may be configured with a length that is longer than the length of the stent holder 207 and the crimped prosthesis 2 added together.

It is contemplated that the prosthetic valve 2 can be crimped over (around) the stent holder sheath 206 proximal to the stent holder 207 and loaded into the valve chamber 201. The valve stent 2 can then be subsequently released from the valve chamber 201 by distally advancing the valve chamber sheath 203 relative to the stent holder 207. The stent holder 207 will prevent distal movement of the prosthesis 2, whereas when the valve chamber 201 is moved distally, the prosthesis 2 will be released from the valve chamber 201 — starting proximally of the valve stent 2 and ending distally of the prosthesis 2.

In one aspect, referring to fig. 6, the stent holder 207 can include a recess 208, the recess 208 configured to receive the projection 8 on the extension member 7 of the prosthetic valve stent frame 3. In operation, the projections 8 on the extension members 7 of the stent 3 will be inserted into the recesses 208 on the stent holder 207, and the stent holder 207 will be advanced into the valve chamber 201 to clamp the projections 8 between the recesses 208 and the inner wall of the valve chamber 201. The prosthesis 2 will be crimped around the stent holder sheath 206 and the stent holder 207 will be advanced to the distal end of the valve chamber 201 to load the crimped prosthesis 2 into the valve chamber 201. To release the prosthesis 2, the valve chamber sheath 203 will be advanced distally while keeping the stent holder 207 positionally fixed. In this aspect, the projections 8 will engage with the stent holder 207 until the valve chamber 201 is advanced enough to expose the recesses 208 in the stent holder 207. It will be appreciated by those skilled in the art that this recess 208 thus acts as a safety mechanism to secure the prosthesis 2 to the VHPL system 1, such that its positioning and manipulation within the heart may be controlled using the VHPL system 1 until it is selectively released.

In one aspect, the valve chamber 201 may have a plurality of slits 205 extending axially from the proximal end of the valve chamber 201, about one to five millimeters (1-5 mm) in length. Slits 205 can be positioned on the valve chamber 201 to align with the holes 9 on the flared portion of the crimped stent 3 so that after DGF member 101 implantation, the trailing DGF member tail 104 can be inserted through the slits 205 of the valve chamber 201, the slits 205 can be designed to correspond to the number and location of the implanted DGF members 101.

In one exemplary aspect, three DGF head members 102 may be implanted first in the annulus: one at the medial commissure representing the P3 location, one at the lateral commissure representing the P1 location, and one in the center of the posterior annulus representing the P2 location. The slits 205 will be located along the circumference of the valve chamber 201 to align with the holes 9 on the medial, lateral and centre respectively of the flared portion of the crimped prosthesis 2 when the crimped prosthesis 2 is loaded into the valve chamber 201, so that the trailing DGF tail 104 can be easily fed through the slits 205 and into the corresponding flared hole 9 and then through the corresponding locking conduit 317 in the VHPL system 1.

In one aspect, the VHPL system 1 may be inserted into the body of a patient and the DGF member tail 104 may be tensioned to guide the valve chamber 201 and hence the valve stent into an operative position at the previously implanted DGF member 101, the valve chamber sheath 203 may be advanced to release the prosthesis starting from the atrial flare 4 and continuing until the entire ventricular part 5 of the prosthesis 2 has been released, once in place at the mitral annulus.

In one aspect, the plurality of locking conduits 317 serve to prevent proximal movement of the prosthesis 2 when the plurality of DGF member tails 104 are tensioned to pull the locking members 105 on the DGF member 101 through the atrial flare aperture 9 of the prosthesis 2, thereby locking the prosthesis 2 in place on the native mitral annulus. The locking catheter 317 is a composite sheath that, in one exemplary aspect, consists of three distinct segments that facilitate fixation of the prosthesis 2. The proximal section of the locking catheter 318 may include, but is not limited to, a long rigid metal tube. The metal tube 318 may span a substantial portion of the delivery system and may serve to control the translation locking catheter 317 through the valve housing, positioning and locking system handle 1. The middle portion of the locking catheter 319 may comprise a flexible material that conforms to the sharp curvature of the deployment path. The flexible portion 319 of the locking catheter 317 can be bent at a small bend radius equal to or greater than about 90 degrees (90 °), to ensure that locking can be achieved along all portions of the annulus. The flexible portion 319 can be made of, but is not limited to, metal, polymer or rubber materials, and the like, and optionally can be characterized by a coiled configuration that allows for low bending stiffness and prevents collapse of the lumen. The distal section of the locking catheter 320 may include a metal locking insert that engages with the locking member 105 and the atrial flare 4 of the prosthetic valve 2 to help secure the prosthetic valve 2 at the DGF body member 103.

In one exemplary aspect, the locking catheter 317 may be attached to a handle to enable an operator to grasp and ease the locking process.

In one aspect, the suture tensioning mechanism may be configured to allow each of the DGF locking members 105 to be independently locked in place on top of the atrial flare portion of the valve 4. In this aspect, each individual DGF member tail 104 is controlled in the suture tensioning mechanism.

In one aspect, the DGF tail tensioning mechanism comprises a ratchet gear and knob assembly. The ratchet gear comprises a circular gear with pivotable teeth. The spring loaded finger members engage the teeth of the gears. The gear teeth are uniform and both slopes on the teeth are symmetrical, allowing the teeth to move in both forward and reverse directions. The stiffness of the spring loaded fingers and the ramps on the gear teeth will allow for controlled progressive rotation of the gears and thus controlled progressive tensioning of the DGF member tail 104.

On the other hand, the gears may be configured with asymmetric ramps to allow rotation in one direction, preventing the DGF tail member 104 from loosening during the procedure.

Further, in describing representative embodiments, the specification may have presented the method and/or process as a particular sequence of steps. However, to the extent that a method or process does not rely on the particular order of steps set forth herein, the method or process should not be limited to the particular sequence of steps described. Other sequences of steps are possible as will be understood by those of ordinary skill in the art. Therefore, the particular order of the steps set forth in the specification should not be construed as limitations on the claims.

While the invention is susceptible to various modifications and alternative forms, specific examples thereof have been shown in the drawings and are herein described in detail. It should be understood, however, that the invention is not to be limited to the particular forms or methods disclosed, but to the contrary, the invention is to cover all modifications, equivalents, and alternatives falling within the scope of the appended claims.

Claims

1. A heart valve leaflet replacement delivery system for implanting a prosthetic heart valve to treat a diseased heart valve, the system comprising:

a prosthetic valve comprising a stent and at least one prosthetic leaflet, the stent comprising a plurality of through-holes;

a multi-stage multi-lumen (MSML) delivery system comprising a dual guidance and securement (DGF) delivery system and a valve containment, positioning and locking (VHPL) system cooperatively configured for advancement to an operative position and for delivery and implantation of a plurality of DGF members to the operative position and for guidance, delivery and securement of a prosthetic valve to the operative position;

a DGF delivery system configured to implant a plurality of DGF members in a native annulus to help guide and secure the prosthetic valve; wherein each DGF member comprises: a head portion configured to be embedded in tissue; a body portion including a securing mechanism; and a tail portion extending from the body portion to a proximal side of the DGF delivery system to guide prosthetic valve delivery via the plurality of through-holes; and

a VHPL system configured to track a plurality of DGF member tail portions to desired implantation locations at a previously implanted DGF member, progressively release the prosthetic valve from a crimped state starting with a proximal-most portion of the prosthetic valve and moving to a distal-most portion of the prosthetic valve, and secure the prosthetic valve to the DGF member via the securing mechanism.

2. The system of claim 1, wherein each head portion is configured with a helix of between 4-10mm in length and between 2-5mm in diameter, the helix being formed with wire of between 0.25-1.0mm in diameter, and wherein each DGF component further comprises a stabilizing member configured as a straight wire of between 0.25-1.0mm in diameter extending axially through the center of the helix, the straight wire having a sharp tip extending between 1-3mm beyond the end of the helix.

3. The system of claim 1, wherein each body portion is configured to attach to a respective head portion and resist separation, and each body portion is configured with a plurality of engagement structures designed to engage with the DGF delivery system, and comprises a plurality of channels, wherein at least one channel is configured for securing a securing mechanism to the body portion, and at least one channel is for attaching a stabilizing member.

4. The system of claim 1, wherein the securing mechanism comprises at least one locking member and at least one tether; wherein the tether is configured to attach the at least one locking member to the body portion, and the at least locking member is configured to pass through a through-hole in the prosthetic valve in only one direction.

5. The system of claim 4, wherein the at least locking member is configured with a plurality of radially compressible legs that flare outwardly, forming a conical or dome shape.

6. The system of claim 4, wherein the at least one locking member is attached to the body portion via a tether looped through a channel in the body portion, wherein the tether is configured with a proximal loop for selectively attaching a tail portion of a respective DGF member.

7. The system of claim 1, wherein the VHPL system comprises:

a valve chamber sheath comprising a distal end carrying a valve chamber, the valve chamber sheath extending proximal to the VHPL system;

a stent holder sheath carrying a stent holder that fits within the valve chamber, the stent holder sheath configured to travel over the valve chamber sheath and extend proximal to the VHPL system;

a plurality of locking catheters positioned proximal to the stent holder and extending to the proximal side of the VHPL system; and

a multi-lumen guiding sheath for housing the stent holder sheath and locking catheter.

8. The system of claim 1, wherein the crimped prosthetic valve is housed in a crimped delivery condition within a valve chamber at a distal end of the VHPL system.

9. The system of claim 8, wherein the valve chamber is configured as a cylinder comprising: a closed distal side; an atraumatic distal tip that prevents tissue damage and assists navigation while in operation; and a mechanism to attach the valve chamber to a valve chamber sheath such that a position of the valve chamber can be controlled by operating the valve chamber sheath on the proximal side of the VHPL system.

10. The system of claim 8, wherein the valve chamber is configured with a plurality of axial slits extending from a proximal end of the valve chamber that align with corresponding through-holes in the prosthetic valve when the prosthetic valve is crimped and loaded within the valve chamber.

11. The system of claim 8, wherein the VHPL system is configured to accommodate a trailing tail of the DGF member implanted prior to valve delivery, wherein a plurality of locking catheters are positioned proximal to the crimped prosthetic valve in the VHPL system.

12. The system of claim 8, wherein a proximal end of the VHPL system is configured with a suture tensioning mechanism to individually, selectively tension the tail portion to guide prosthetic valve delivery and fixation.

13. The system of claim 12 wherein the suture tensioning mechanism comprises an assembly of ratchet gears such that the DGF member can be selectively attached and detached from the assembly and selectively rotating the gear in one rotational direction increases tension in the tail portion, rotating the gear in another rotational direction releases tension in the tail portion, and non-rotating maintains previously reached tension in the tail portion.

14. The system of claim 1, wherein the prosthetic valve stent is configured with at least one elongate member extending between about two and six millimeters (2-6 mm) from a lower flared portion of the stent, and wherein the lower flared portion can be configured to be straight or curved radially inward.

15. The system of claim 14, wherein the at least one elongate member is configured to selectively engage the VHPL system such that the prosthetic valve can be guided, expanded, and fixed in position at a plurality of DGF members prior to selectively disengaging the prosthetic valve from the VHPL system.

16. The system of claim 15, wherein the at least one projection at the distal tip of the elongate member is configured to fit within at least one recess in a stent holder positioned distally of the prosthetic valve when the prosthetic valve is crimped within a valve chamber, such that the prosthetic valve can be selectively attached to the VHPL system by placing the at least one projection within the at least one recess in the stent holder and inserting the stent holder into the valve chamber such that the projection is sandwiched between an inner wall of the valve chamber and the at least one recess in the stent holder, and the prosthetic valve can be selectively detached from the VHPL system by advancing the valve chamber distally relative to the stent holder to expose the at least one recess in the stent holder and release the projection.

17. The system of claim 3, wherein each head member is configured to be implanted through an upper flared portion of the prosthetic valve such that a plurality of additional DGF members can be implanted on top of the prosthetic valve in the operative position after the prosthetic valve has been secured in place with DGF locking members by a plurality of previously implanted DGF members.