CN116407346A - Artificial valve fixation device and valve replacement device comprising same - Google Patents

Abstract

The present application relates to an artificial valve fixing device, which is used to fix the artificial valve to the leaflets of the native valve, comprising: an inner bracket having an open proximal end, an open distal end and an opening along the proximal end and the open distal end. a tubular sidewall extending along the longitudinal axis of the prosthetic valve fixing device; and an outer frame having a three-dimensional annular shape bent along the axial direction and configured to be sleeved on the radially outer side of the inner frame; wherein the The inner stent and the outer stent are configured to clamp each leaflet of the native valve between the inner stent and the outer stent to secure the prosthetic valve fixation device to the leaflets of the native valve , and wherein the outer stent is fixedly connected to the inner stent in an axial direction along the longitudinal axis. The present application also relates to a valve replacement device comprising the above artificial valve fixing device.

Description

Artificial valve fixation device and valve replacement device comprising same

technical field

One aspect of the present application relates generally to a prosthetic valve fixation device, and in particular, to a device for securing a prosthetic valve to a native valve. Another aspect of the present application relates to a valve replacement device comprising the above artificial valve fixing device.

Background technique

Valvular disease is a common cardiovascular disease, including deformity, valvular stenosis, calcification, regurgitation and regurgitation caused by congenital hypoplasia or acquired disease and aging. These valvular diseases alter the normal flow dynamics of blood, and in turn cause a series of symptoms, such as palpitation after activity, shortness of breath, fatigue, edema, angina pectoris, fainting, etc. In particular, aortic valve calcification, stenosis, and regurgitation and regurgitation are common valvular diseases.

For patients with aortic valve calcification and stenosis, transcatheter aortic valve implantation (TAVI) is a common treatment in recent years. In TAVI, a balloon is delivered to the aortic valve area via, for example, the femoral artery by an interventional delivery device such as a sheath, and the balloon is radially inflated to squeeze the native valve apart to expose the annulus. A prosthetic valve, such as made from porcine pericardium, secured to a prosthetic valve fixation device is then collapsed into the interventional delivery device and delivered to the aortic valve area via, for example, the femoral artery. After reaching the aortic valve area, the balloon wrapped inside the artificial valve fixing device is radially expanded again, so as to force the artificial valve fixing device to radially expand, so as to be radially supported in the annulus of the aortic valve. After removal of the balloon and interventional delivery device, the implanted prosthetic valve replaces the function of the native valve, opening and closing as the left ventricle contracts and relaxes. Since the annulus of the native aortic valve of patients with aortic valve calcification and stenosis can provide a strong reaction force for the radial support of the artificial valve fixing device, the above-mentioned artificial valve fixing device can be relatively firmly fixed on this type of valve annulus. Inside.

However, for patients with simple aortic regurgitation (no stenosis or calcification of the aortic valve), the annulus tissue of the native aortic valve is usually too soft to provide sufficient radial support. In this case, it is often difficult to use the above-mentioned artificial valve fixing device to fix the artificial valve at the native valve annulus through radial support force. In addition, for patients with bicuspid aortic valve deformity accompanied by simple regurgitation without stenosis and calcification, it is also difficult to use the above artificial valve fixation device for treatment because the valve ring tissue is usually relatively soft. It can be seen that in the field of valve replacement devices, there is a need for an artificial valve fixing device with an improved fixing method and a valve replacement device comprising it, so as to solve the problem of valves without stenosis and calcification (such as simple aortic valves and pulmonary valves). sexual reflux disease, etc.) in the treatment of patients with prosthetic valves.

Contents of the invention

The prosthetic valve normalization and fixation device and the valve replacement device incorporating the same according to embodiments of the present application at least partially address the above-mentioned problems and other problems that will be discussed below. One aspect of the present application relates to a prosthetic valve fixation device for securing a prosthetic valve to leaflets of a native valve. The artificial valve fixation device may include an inner stent and an outer stent. The inner stent may have an open proximal end, an open distal end, and a tubular sidewall extending along the longitudinal axis of the prosthetic valve fixation device between the open proximal end and the open distal end. The outer stent may have a three-dimensional annular shape bent and extended in the axial direction, and may be configured to be sleeved on the radially outer side of the inner stent. The inner stent and the outer stent can be configured to clamp each leaflet of the native valve between the inner stent and the outer stent, so as to fix the artificial valve fixing device on the leaflet of the native valve. The outer stent can be connected to the inner stent in an axial direction along the longitudinal axis. By clamping the leaflets of the native valve, the artificial valve fixing device according to the present application can position the artificial valve carried by the leaflets of the native valve without relying on the radial support force to be supported on the inner circumference of the valve annulus, so it is suitable for In patients with valvular disease without calcification or stenosis. The three-dimensional, generally annular shape of the outer stent can "catch" the leaflets of the native valve from the outside, while the inner stent can push the leaflets toward the outer stent from the inside. In addition, the outer stent is fixedly connected to the inner stent in the axial direction along the longitudinal axis, eliminating the relative axial movement of the inner and outer stents during implantation, thereby simplifying the complexity of the interventional delivery device and implantation process , and reduces the risk of operational failure.

In some embodiments, the outer stent is configured such that, after the radial compressive force is radially compressed from the expanded state to a contracted radial dimension in the compressed state, when the radial compressive force is removed from the outer stent, The outer stent is at least partially self-expanding to return to the original radial dimension in the deployed state. With the help of the self-expanding property of the outer stent, the outer stent of the artificial valve fixation device according to the present application can at least partially recover its diameter by itself when protruding from the distal end of the interventional delivery device during implantation. Therefore, it is only necessary to adjust the circumferential angle of the artificial valve fixing device before capturing the leaflets of the native valve, without using expansion devices such as balloons to restore or expand the diameter of the outer stent.

In some embodiments, the outer diameter of the outer stent in the expanded state is not larger than the inner diameter of the annulus of the native valve, and the outer diameter is preferably 15mm-30mm. The artificial valve fixing device according to the present application is supported on the inner circumference of the valve annulus without relying on radial support force, so it can avoid any additional damage to the valve annulus while ensuring that the artificial valve fixing device does not shift.

In some embodiments, the outer scaffold is made of a shape memory material or a superelastic material. In some embodiments, the shape memory material is a shape memory nickel titanium alloy. Shape-memory nickel-titanium alloys such as Nitinol have good shape memory properties, so that the outer stent can recover to a large extent by itself to the original diameter of the deployed state, such as returning to more than 90% of the original diameter, preferably more than 95%, More preferably above 99%, and most preferably fully restored to the original diameter. In addition, the material also has excellent biocompatibility to reduce rejection.

In some embodiments, the three-dimensional annular shape of the outer stent comprises at least two distal raised portions, each of the at least two distal raised portions for clamping a corresponding leaflet of the native valve in a corresponding distal raised portion. Between the lifting part and the inner bracket. During the implantation procedure, the outer stent externally sleeves the leaflets of the native valve in a distal direction from proximal to distal. The distal raised portion faces the leaflet in a distal direction so as to capture it in the space between the outer stent and the inner stent in the retracted state.

In some embodiments, each of the at least two distal raised portions has a "U" shape. The "U" shape has rounded edges to avoid damaging or irritating the leaflets of the native valve.

In some embodiments, each pair of adjacent distal raised portions of the at least two distal raised portions are connected together at a proximal connecting portion to connect them to form a complete three-dimensional annular shape of the outer stent.

In some embodiments, the proximal connection portion is fixedly connected to the inner stent such that the outer stent is fixedly connected to the inner stent as a whole, in particular in an axial direction along the longitudinal axis.

In some embodiments, the outer frame can be connected to the inner frame by wire suture or binding, welding or welding.

In some embodiments, the inner stent has a compressible grid-like structure, so as to be collapsed and accommodated in an interventional delivery device such as a sheath.

In some embodiments, the inner stent is configured such that, after the radial compressive force is radially compressed from the expanded state to the compressed state, when the radial compressive force is removed from the inner stent, the inner stent at least partially retains the compressed state. When protruding from the distal end of the interventional delivery device during implantation, the outer stent of the artificial valve fixation device according to the present application can at least partially recover its diameter by itself, while the inner stent can at least partially maintain the compressed diameter, thereby in both Space is left in between to capture the leaflets of the native valve.

In some embodiments, the inner stent is configured such that, with the inner stent in the compressed state, the inner stent expands radially from the compressed state to the expanded state when a radially outward force is applied to the inner stent. After the leaflets of the native valve are captured in the space between the inner stent and the outer stent, the outer diameter of the inner stent can be expanded to be close to the diameter of the outer stent by means of radial expansion of an instrument such as a balloon arranged inside the inner stent. inner diameter, thereby clamping the leaflets between the two.

In some embodiments, the endostent is made of a non-shape memory material (ie, a material that does not have shape memory properties or superelasticity), such as cobalt chrome or stainless steel. Stents made from these materials are capable of retaining the compressed state dimensions after being compressed and the compressive force is removed, and are capable of returning to the expanded state dimensions when an expanding force is applied.

Another aspect of the present application relates to a valve replacement device, comprising the artificial valve fixing device and the artificial valve according to any one of the above embodiments. The perimeter of the prosthetic valve is secured to the inner surface of the inner stent. In some embodiments, the artificial valve can be made of natural materials such as porcine pericardium and bovine pericardium, or artificially synthesized biocompatible synthetic materials.

Description of drawings

The artificial valve fixing device and the valve replacement device according to various embodiments of the present application are described below with reference to the accompanying drawings. As used hereinafter, the term "artificial valve" means that it is made of natural materials such as porcine pericardium and bovine pericardium or biocompatible synthetic materials and functions to open, A membranous one-way valve structure with a closing function, excluding devices for securing the structure to the implanted site; the term "prosthetic valve fixation device" means a device for carrying such a "prosthetic valve" and securing the "prosthetic valve" to and the term "valve replacement device" means the combination of such "prosthetic valve fixation device" and such "prosthetic valve", wherein the periphery of the "prosthetic valve" can be fixed to the "prosthetic valve" Fixtures" on the inside.

It should be understood that the accompanying drawings are for illustration and explanation purposes only, and are not intended to constitute any limitation on the protection scope of the present application. In addition, each drawing only schematically shows the position and combination relationship of each component, and is not necessarily drawn to scale, wherein:

FIG. 1 is a schematic perspective view illustrating an artificial valve fixing device in a deployed state according to an embodiment of the present application;

2 is a schematic perspective view illustrating a prosthetic valve fixation device in a compressed state according to an embodiment of the present application;

3 is a schematic perspective view illustrating a valve replacement device retracted within an interventional delivery device according to an embodiment of the present application;

4 is a schematic perspective view illustrating a valve replacement device protruding from an interventional delivery device according to an embodiment of the present application;

5A is a schematic perspective view illustrating a valve replacement device during a process of capturing leaflets according to an embodiment of the present application;

Figure 5B is a schematic bottom view illustrating a valve replacement device during the process of capturing leaflets according to one embodiment of the present application;

5C is a schematic bottom view illustrating a valve replacement device during a process of capturing leaflets according to another embodiment of the present application;

6A is a schematic perspective view illustrating a valve replacement device during a process of clamping a leaflet according to an embodiment of the present application;

6B is a schematic bottom view illustrating a valve replacement device during the process of clipping the leaflets according to one embodiment of the present application;

6C is a schematic bottom view illustrating a valve replacement device during a process of clamping a leaflet according to another embodiment of the present application;

7A is a schematic perspective view illustrating a valve replacement device after implantation according to an embodiment of the present application;

7B is a schematic bottom view illustrating a valve replacement device after implantation is completed according to an embodiment of the present application;

Fig. 7C is a schematic bottom view illustrating a valve replacement device according to another embodiment of the present application after implantation is completed.

In some of these drawings, the illustration of some components may be omitted for the purpose of clarity of illustration or avoiding occlusion, which should not be interpreted as indicating that the corresponding components are not included in the illustrated embodiments.

Detailed ways

The artificial valve fixing device and the valve replacement device including the same, and the implantation process thereof according to the embodiments of the present application are described in detail below with reference to the accompanying drawings, wherein the same reference numerals refer to the same or corresponding elements in several views. As used herein, the term "distal" refers to the direction in which artificial valve fixation devices, valve replacement devices, interventional delivery instruments (such as sheaths, etc.) or parts thereof are far away from operators (such as doctors) (such as, as The lower left of each schematic perspective view 1, 2 and the lower right of each schematic perspective view 3, 4, 5A, 6A, 7A; in particular, for the aortic valve, indicates the direction perpendicular to the plane of the aortic valve from the aorta to the left ventricle direction), and the term "proximal" refers to the direction in which artificial valve fixation devices, valve replacement devices, implantation devices, interventional delivery devices (such as sheaths, etc.) or parts thereof are closer to operators (such as doctors) (such as, Such as the upper right of each schematic perspective view 1, 2 and the upper left of each schematic perspective view 3, 4, 5A, 6A, 7A; in particular, for the aortic valve, it means that it is perpendicular to the plane of the aortic valve from the left ventricle to the aorta direction). In other words, during the implantation process, the "distal end" of the artificial valve fixation device, valve replacement device, implantation device (such as an interventional delivery device such as a sheath), etc., or the inner stent, outer stent, etc. is the end that first enters the patient's body , while the "proximal end" is the other end that enters the patient. In this application, "valve" is used interchangeably with other valves such as aortic valve, pulmonary valve, etc., because the artificial valve fixation device and valve replacement device according to this application can be applied to repair various valves, as long as the The specific configuration of the inner and outer stents should be adjusted according to the number, size, shape and treatment needs of the leaflets to be treated. Therefore, the following explains the structure of the artificial valve fixing device and valve replacement device according to the present application, although it may be for the case of aortic valve bicuspid deformity (hereinafter used interchangeably with "bicuspid valve"). Functions and their functions and beneficial effects, but it should be understood that these components and their functions and beneficial effects are also applicable to the repair and treatment of other valve diseases.

One aspect of the present application relates to a prosthetic valve fixation device 100 . FIG. 1 is a schematic perspective view illustrating an artificial valve fixing device 100 in a deployed state according to an embodiment of the present application. As shown in FIG. 1 , the artificial valve fixing device 100 may include an outer stent 120 and an inner stent 140 , and the outer stent 120 is radially sleeved on the outside of the inner stent 140 . Inner stent 140 may have an open proximal end 146 , an open distal end 142 , and a tubular sidewall 144 extending along the longitudinal axis of prosthetic valve fixation device 100 between open proximal end 146 and open distal end 142 . The outer bracket 120 may have a three-dimensional ring shape. In other words, the outer stent 120 generally completely surrounds the outer side of the inner stent 140, but the annular structure of the outer stent 120 may not be in the same plane, but include a distal and/or The proximal undulations form an annular shape in three dimensions to facilitate capturing and clamping the leaflets of the native valve, as will be described in more detail below with reference to the accompanying drawings. In other words, the outer bracket 120 may be end-to-end annular in a bottom view viewed along the longitudinal axis, and may appear distally and/or proximally along the longitudinal axis in a side view viewed along the radial direction. Non-planar structures with raised ground. By clamping the leaflets of the native valve between the inner stent 140 and the outer stent 120, the artificial valve fixing device 100 can locate the carried artificial valve at the native valve position by means of the native valve leaflets without completely relying on the radial direction. The supporting force rests on the inner periphery of the annulus of the native valve.

In some embodiments, the outer bracket 120 can be fixedly connected to the inner bracket 140 in an axial direction along the longitudinal axis. In this case, when changing between a collapsed state (e.g., radially compressed to be collapsed within the interventional delivery device) and an expanded state (e.g., extended from the interventional delivery device and deployed in preparation for capturing the valve leaflets), There will not be any significant axial relative movement between the outer frame 120 and the inner frame 140 . Correspondingly, the interventional delivery device does not need to be equipped with components for delivering and releasing the outer stent 120 and the inner stent 140 respectively, thereby simplifying the complexity of the interventional delivery device and the complexity of the implantation process, and avoiding the increase of the outer diameter of the delivery push efficiency. In addition, this avoids relative axial position errors or misalignments that may be introduced when the outer stent 120 moves axially relative to the inner stent 140, thereby reducing the risk of implant failure. In some embodiments, the outer frame 120 can be axially fixedly sutured or bound to the inner frame 140 by thin wires such as nickel-titanium wire, or can be completely fixedly connected to the inner frame 140 by welding, welding, or the like.

FIG. 2 is a schematic perspective view illustrating the artificial valve fixing device 100 in a compressed state according to an embodiment of the present application. As shown in FIG. 2 , under radial compressive force, both the inner stent 140 and the outer stent 120 of the artificial valve fixing device 100 shrink to a smaller radial size in the radial direction. Still referring to FIG. 2 , in some embodiments, since the outer stent 120 can be fixedly connected to the inner stent 140 in an axial direction along the longitudinal axis, the outer stent 120 can be compared with the deployed state shown in FIG. 1 . The relative axial position between the inner stents 140 does not change in the contracted state. Applying a radial compressive force to the artificial valve fixing device 100 can be performed by existing or yet to be developed equipment in the art, for example, by crimping equipment or a loading tool, so as to be shrunk and accommodated in an interventional delivery device such as a sheath, as shown in Figure 3 shown. In some embodiments, the inner stent 140 in the contracted state may be pierced with an expansion device such as a balloon, as will be described in more detail later with reference to the accompanying drawings.

In some embodiments, after the prosthetic valve fixation device 100 is shrunk to the contracted state shown in FIG. When the prosthetic valve fixing device 100 is stretched out from the distal end of the interventional delivery device such as the sheath during the implantation process), the outer support 120 can self-expand to at least partially return to the original radial direction in the expanded state shown in FIG. 1 . size. By virtue of the self-expanding properties, when protruding from the distal end of the interventional delivery device during implantation, the outer stent 120 of the artificial valve fixing device 100 according to the present application can at least partially recover its diameter by itself, and each part of the outer stent 120 can at least partially to restore the original shape in the unfolded state. Therefore, it is only necessary to adjust the circumferential angle of the prosthetic valve fixing device 100 before capturing the leaflets of the native valve, without using expansion devices such as balloons to restore or expand the diameter of the outer stent 120 . Understandably, this simplifies the steps required to be manipulated during the implantation process and shortens surgical time, which may improve patient outcomes.

In some embodiments, outer frame 120 is made of a shape memory material or a superelastic material. In some embodiments, the shape-memory material is a shape-memory alloy, such as a shape-memory nickel-titanium alloy, such as Nitinol, which has good shape-memory properties. Alternatively, the outer frame 120 can also be made of other biocompatible and durable shape memory materials or superelastic materials existing or yet to be developed in the art, such as metals or polymers with shape memory or superelastic properties Material. The shape memory or superelastic properties of the material enable the outer stent 120 to have the above-mentioned self-expanding property, that is, it can recover to a large extent by itself to the original radial dimension of the deployed state after the radial compressive force is removed, such as returning to the original More than 90% of the diameter, preferably more than 95%, more preferably more than 99%, and most preferably fully restored to the original diameter.

In some embodiments, the three-dimensional annular shape of the outer stent 120 may include at least two distal raised portions 122, each distal raised portion 122 along the side of the prosthetic valve fixing device 100 in a radial direction. The longitudinal axis is convex distally. The distal raised portion 122 serves to capture and clamp the corresponding leaflet of the native valve between itself and the inner stent 140 . During the implantation procedure, the outer stent 120 may laterally sleeve the leaflets of the native valve in a proximal-to-distal distal direction. The distal raised portion 122 may face the leaflets in a distal direction so as to capture it in the space between the outer stent 120 and the inner stent 140 in the collapsed state, as will be described in more detail below with reference to FIGS. 4-6C . describe. In some embodiments, each distal raised portion 122 may have a "U" shape with a curvilinear base of the "U" extending distally along the longitudinal axis. The "U" shape has rounded edges to avoid damaging or irritating the leaflets of the native valve. In some embodiments, as shown in FIG. 1 , each pair of adjacent distal raised portions 122 may be connected together at a corresponding proximal connecting portion 124 to form a complete three-dimensional annular shape of the outer stent 120 . In some embodiments, as shown in FIG. 1 , each proximal connection portion 124 can be loosely or tightly stitched/bundled by wire, or fixedly connected to the outer periphery of the inner frame 140 by welding, welding, etc., so that The outer bracket 120 is fixedly connected to the inner bracket 140 in an axial direction along the longitudinal axis.

In addition, in some embodiments, the at least two distal raised portions 122 of the three-dimensional annular shape of the outer stent 120 may include a pair of opposite distal raised portions 122 connected at a pair of proximal connecting portions 124 together, as shown in Figure 1 and Figure 2. In this case, the pair of opposed distal raised portions 122 may each be used to capture and hold a corresponding leaflet of a pair of leaflets between itself and the inner frame 140 . Therefore, the artificial valve fixing device 100 according to these embodiments is particularly suitable for the treatment of valve diseases with two valve leaflets, such as the treatment of simple regurgitant aortic valve bicuspid deformity without stenosis and calcification. Even if the annulus of the bicuspid aortic valve of patients with this disease cannot be installed only by radial support due to the softness of the tissue, the artificial valve fixing device 100 according to these embodiments can also be installed by using a The pair of leaflets are clamped between the pair of opposed distal raised portions 122 of the outer stent 120 and the inner stent 140 to position the prosthetic valve in place of the native aortic valve.

In some embodiments, the three-dimensional annular shape of the outer stent 120 forms part of the tubular sidewall 144 in the deployed state. In other words, in the bottom view viewed from the distal side to the proximal side as shown in FIG. 5B , FIG. 5C , FIG. 6B , FIG. 6C , FIG. 7B and FIG. 7C , the outer stent 120 in the deployed state exhibits a ring shape. As an example, a cylindrical barrel of material may be cut by a process such as laser cutting to create the three-dimensional annular shape of outer bracket 120 . Alternatively, when the inner annulus wall of the native valve deviates significantly from the cylindrical shape, a tube of material simulating the native annulus shape can also be cut to make the three-dimensional annular shape of the outer stent 120 . In this case, when the artificial valve fixation device 100 is implanted so that the longitudinal axis is perpendicular to the plane of the native valve, the three-dimensional annular shape of the outer support 120 in the expanded state can best match the shape of the inner wall of the native valve annulus as a whole. , as will be described in more detail later with reference to FIG. 7A .

Since there is no need to rely on the radial support force to support the inner circumference of the original valve annulus, the artificial valve fixing device 100 according to the embodiment of the present application can be applied to the treatment of valve diseases without stenosis and calcification, even if the original valve The ring cannot provide sufficient reaction force for the radial support of the artificial valve fixing device 100 due to soft tissue. Correspondingly, in some embodiments, the outer diameter of the outer stent 120 in the expanded state may not be greater than the inner diameter of the annulus of the native valve, so that there may be substantially no radially outward supporting force after implantation, so as to avoid damage to the valve. rings for any additional damage. In other words, after implantation, the outer diameter of the outer stent 120 can be exactly equal to the inner diameter of the annulus of the native valve, so as to fit on the inner circumference of the annulus, but there is no need to generate radial expansion force on the annulus, or only a small The force of radial expansion; alternatively, the outer diameter of the outer stent 120 may also be slightly larger or slightly smaller than the inner diameter of the annulus of the native valve, so as to facilitate positioning and operation during implantation. It can be understood that the diameter of the outer stent 120 should not be too small to avoid paravalvular leakage. Preferably, the outer diameter of the outer stent 120 in the expanded state is 15 mm to 30 mm. In this way, when the inner diameter of the annulus of the native valve is constant, the outer diameter of the artificial valve fixing device 100 in the embodiment of the present application is smaller than that in the prior art. The outer diameter of the desired prosthetic valve stent.

In some embodiments, the tubular sidewall 144 of the inner stent 140 can have a lattice structure, so as to improve the radial compressibility, so that it can be accommodated in a smaller delivery diameter (profile) and more conveniently. into the delivery device. In some embodiments, the grid-like structure may be composed of polygonal grids such as hexagonal grids, quadrilateral grids, or combinations thereof in the unfolded state. It can be appreciated that the hexagonal mesh and quadrilateral mesh inner scaffold 140 are easier to be compressed to a smaller radial dimension or expanded to return to the original Radial dimension.

In some embodiments, the inner stent 140 can be configured to, after being radially compressed from the expanded state to the compressed state by a radial compressive force, at least partially retain the radial compressive force when the radial compressive force is removed from the inner stent compressed state. In other words, the inner stent 140 does not have self-expanding properties, or at least does not spontaneously fully expand back to its original radial dimension in the deployed state. When protruding from the distal end of the interventional delivery device during implantation, the outer stent 120 of the artificial valve fixation device 100 can at least partially restore itself to the original diameter in the expanded state, while the inner stent 140 can at least partially maintain the compressed diameter. radial dimension, and will not spontaneously fully expand and return to the original radial dimension in the deployed state, thereby retaining a space between the inner stent 140 and the outer stent 120 to capture the leaflets of the native valve, as will be referred to in the following figure 4—Figure 5C is described in more detail.

In some embodiments, the inner stent 140 can be configured such that, in the compressed state, the inner stent 140 can radially expand from the compressed state when a radially outward force is applied on the inner surface of the inner stent 140 to the original radial size of the expanded state. After the leaflets of the native valve are captured in the space between the inner stent 140 and the outer stent 120, the outer diameter of the inner stent 140 can be expanded by means of radial expansion of an instrument such as a balloon placed inside the inner stent 140 to approach the inner diameter of the outer stent 120, thereby clamping the leaflets therebetween, as will be described in more detail below with reference to FIGS. 6A-6C.

In some embodiments, inner stent 140 may be made of a non-shape memory material. In other words, the material of the inner stent 140 may not have self-expandability, shape memory property or superelasticity. In some embodiments, the material may be cobalt-chromium alloy or stainless steel, or a biocompatible and durable material with high rigidity existing or yet to be developed in the art. It will be appreciated that the inner stent 140 fabricated from these materials is capable of at least partially maintaining the radial dimension of the compressed state after being compressed and the compressive force is removed, and is capable of returning to the radial dimension of the expanded state upon application of the expanding force.

In some embodiments, the inner stent 140 and/or the outer stent 120 can be coated with a biocompatible coating, such as polyethylene terephthalate (PET), to improve biocompatibility and reduce rejection. response and promote endothelialization.

Another aspect of the present application relates to a valve replacement device, which includes the artificial valve fixing device 100 and the artificial valve in any embodiment of the above aspects. In some embodiments, the periphery of the prosthetic valve can be fixed to the inner surface of the inner stent 140 to form an integral body together with the prosthetic valve fixing device 100 and the annulus of the native valve to realize the function of the prosthetic valve. In some embodiments, the artificial valve can have, for example, three leaflets, and is sutured to the inner surface of the inner frame 140 at several points around it, or fixed to the inner surface of the inner frame 140 with a structure such as a base (not shown). The inner surface. In some embodiments, the artificial valve can be made of existing or yet to be developed material membranes in the field, such as natural materials such as porcine pericardium and bovine pericardium, or synthetic materials with biocompatibility and durability.

The implantation process of the valve replacement device including the artificial valve fixing device 100 and the artificial valve according to the present application will be explained below with reference to FIGS. 3-7C . Although in these drawings and the following description, reference is made to the treatment process for aortic valve bicuspid deformity, and the prosthetic valve fixation device 100 is shown and described as including a pair of distal raised portions 122, but Prosthetic valve fixation devices 100 and valve replacement devices according to the present application may also include a greater number (e.g., three) of distal raised portions 122 and be used to treat valves with three leaflets (such as non-bicuspid valves). Valvular malformation of the aortic valve, pulmonary valve, tricuspid valve, etc.) valve disease. In addition, in these drawings, the illustration of the artificial valve may be omitted for the purpose of clarity of illustration and avoiding occlusion, but only the artificial valve fixing device 100 is shown, which does not mean that there are no artificial valves during these implantation processes. Contains prosthetic valves.

FIG. 3 is a schematic perspective view illustrating a valve replacement device collapsed within an interventional delivery instrument 200 according to an embodiment of the present application. In the contracted state shown in FIG. 3, the valve replacement device is delivered to the vicinity of the aortic valve using an interventional delivery instrument 200, such as a sheath, through a minimally invasive surgical procedure such as a femoral intervention. As shown in FIG. 3 , the prosthetic valve fixing device 100 is compressed radially to a contracted size in a compressed state, and is contracted and housed in the interventional delivery device 200 . At this time, both the inner stent 140 and the outer stent 120 of the prosthetic valve fixing device 100 may be radially compressed, and the inner stent 140 and the outer stent 120 are positioned near the distal end of the interventional delivery device 200 such as a sheath. Although not shown, the prosthetic valve of the valve replacement device may also be retracted inside the inner stent 140 at this time. In addition, an expansion device such as a balloon (not shown in FIG. 3 ) can be sheathed inside the contracted inner stent 140, so that the inner stent 140 that does not have self-expanding properties can be expanded to return to the diameter of the expanded state in subsequent operations. to size. In some embodiments, the balloon can be connected to the distal end of a catheter (not shown) to form a balloon catheter, and the balloon catheter can also move axially along the guide wire (not shown), driving the valve replacement device and The sheath is delivered to the target site.

FIG. 4 is a schematic perspective view illustrating a valve replacement device protruding from an interventional delivery device 200 according to an embodiment of the present application. As an example, after reaching the target position, the valve replacement device may be driven to protrude from the distal end of the sheath through the distal movement of the balloon catheter relative to the sheath. It should be understood that at this time, the entire valve replacement device is still located near the aortic valve, that is, located on the aortic side without passing through the aortic valve plane to the left ventricle side. At this time, under the action of the self-expanding property of the shape memory material or the superelastic material of the outer stent 120, the outer stent 120 self-expands to at least partially recover to the original radial dimension in the deployed state, while the inner stent 140 still at least partially maintains The contracted radial dimension in the contracted state. In this case, by rotating the valve replacement device, the pair of distal protrusions 122 of the outer frame 120 of the artificial valve fixing device 100 can be respectively aligned with the pair of native aortic valves of the bicuspid aortic valve in the circumferential direction. leaflets in preparation for capturing the pair of native leaflets.

5A is a schematic perspective view illustrating a valve replacement device during a process of capturing leaflets according to an embodiment of the present application. As shown in FIG. 5A, after the extension and alignment operations described above with reference to FIG. The distal ends of the stent 120 and/or the inner stent 140 are substantially abutted against the proximal side of the aortic valve (i.e., the aortic side), so that the pair of native valve leaflets are covered by a pair of distal convex ends of the expanded outer stent 120. In the space between the raised portion 122 and the retracted inner stent 140. At this time, the outer stent 120 can be substantially fitted to the annulus 300 of the aortic valve, but the artificial valve fixing device 100 is fixed without relying on the radial support force between the outer stent 120 and the annulus 300 .

Fig. 5B is a schematic bottom view illustrating the valve replacement device during the process of capturing leaflets according to an embodiment of the present application (taking the aortic valve as an example, a view viewed from the left ventricle toward the aorta). As shown in FIG. 5B , at this time, the inner stent 140 together with the artificial valve 500 is sleeved on the outer periphery of the expansion device 400 such as a balloon, and the outer stent 120 has self-expanded to a radial dimension close to or equal to the inner diameter of the annulus 300 . In this embodiment, the outer bracket 120 and the inner bracket 140 are fixedly connected to each other only in the axial direction, but not necessarily fastened together in the radial direction. As an example, the outer frame 120 may be loosely bound/sewn with wire at a pair of proximal connection portions 124 at the corresponding positions of the inner frame 140 . In this case, there may be a radial space d1 between the distal raised portion 122 of the outer stent 120 and the inner stent 140 for accommodating native valve leaflets. In addition, as shown in FIG. 5B , at this time, the artificial valve 500 can be stretched by the expansion device 400 such as a balloon, so as to be attached to the inner side of the inner stent 140 .

Fig. 5C is a schematic bottom view illustrating a valve replacement device according to another embodiment of the present application during the process of capturing leaflets (taking the aortic valve as an example, a view viewed from the left ventricle toward the aorta). Compared with the embodiment shown in FIG. 5B , the outer frame 120 in the embodiment shown in FIG. 5C can be tightly bound/sewn with the inner frame 140 at a pair of proximal connection portions 124 by, for example, welding, welding, or wire and so on are fastened to each other. Thus, when the outer stent 120 extends out of the sheath and self-expands, the inner stent 140 is also at least partially expanded in a direction corresponding to the pair of proximal connection portions 124 of the outer stent 120 . In contrast, the inner stent 140 still at least partially maintains the radial dimension in the contracted state in the direction corresponding to the pair of distal raised portions 122 of the outer stent 120, so as to be connected to the distal side of the outer stent 120. A radial space d2 is left between the raised portions 122 for accommodating the leaflets that capture the native valve. It can be appreciated that in this case, the prosthetic valve 500 is also at least partially deployed along with the inner stent 140 in a direction corresponding to the pair of proximal connecting portions 124 of the outer stent 120, and still rests against the unexpanded balloon .

6A is a schematic perspective view illustrating a valve replacement device according to an embodiment of the present application during a leaflet clamping process, wherein the illustration of the prosthetic valve is omitted in order to illustrate the deployment of the balloon. After snapping a pair of native valve leaflets into the space between the pair of distal raised portions 122 of the expanded outer stent 120 and the collapsed inner stent 140, as shown in FIG. The expansion device 400 such as a balloon is radially expanded, thereby expanding the inner stent 140 in the radial direction to at least partially restore the radial size of the deployed state, so as to firmly clamp the captured native valve leaflets v1, v2 on the outer stent 120 and the inner frame 140. After that, the original valve leaflets v1 and v2 will always be in an open state due to being clamped, and will no longer play the function of opening and closing the valve, and the valve replacement device has been fixed on the original valve leaflet by clamping the original valve leaflets v1 and v2. location.

Fig. 6B is a schematic bottom view illustrating the valve replacement device according to an embodiment of the present application during the process of clipping the leaflets (taking the aortic valve as an example, a view viewed from the left ventricle toward the aorta). Corresponding to the embodiment shown in FIG. 5B , in the embodiment shown in FIG. 6B , the outer frame 120 can be loosely bound/sewn to the corresponding position of the inner frame 140 at a pair of proximal connecting parts 124 superior. As shown in FIG. 6B , during the leaflet clamping procedure shown in FIG. 6A , expansion device 400 , such as a balloon, is expanded such that inner stent 140 expands in radial dimension until approaching the inner diameter of outer stent 120 . At this time, the radial space between the inner frame 140 and the pair of distal protrusions 122 of the outer frame 120 is reduced to d3, so as to securely clamp the captured original leaflets v1, v2 between the inner frame 140 and the distal side. between the side raised portions 122 . It can be understood that during this process, the artificial valve 500 is pushed by the expansion device 400 to be close to the inner wall of the inner stent 140 . After this process, the artificial valve fixing device 100 together with the carried artificial valve 500 has been fixed at the position of the original valve by clamping the native valve leaflets v1 and v2.

Fig. 6C is a schematic bottom view illustrating a valve replacement device according to another embodiment of the present application during the process of clamping the leaflets (taking the aortic valve as an example, a view viewed from the left ventricle toward the aorta). Similar to the embodiment shown in FIG. 6B corresponding to the embodiment shown in FIG. 5B, the embodiment shown in FIG. 6C may correspond to the embodiment shown in FIG. 124 and the inner bracket 140 are fastened to each other by methods such as welding, welding or tight binding/sewing of metal wires. Similarly, after the inner stent 140 is expanded using the expansion device 400, the radial space between the inner stent 140 and the pair of distal raised portions 122 of the outer stent 120 is reduced to d4 to capture the native valve leaflet v1 , v2 are firmly clamped between the inner bracket 140 and the distal raised portion 122 .

FIG. 7A is a schematic perspective view illustrating the implantation of the valve replacement device according to an embodiment of the present application, wherein the illustration of the artificial valve is omitted in order to clearly show the inner stent 140 and the valve ring 300 . After clamping the native valve leaflets v1, v2, the expansion device 400 such as a balloon is deflated and the interventional delivery instrument (not shown in FIG. 7A ) such as guide wire, sheath and balloon catheter is removed from the patient. So far, the implantation process of the valve replacement device according to the embodiment of the present application is completed. After the expansion device 400 is contracted, the artificial valve (not shown in FIG. 7A ) returns to a normal working state by being close to the inner wall of the inner stent 140, thereby replacing the function of the original aortic valve, that is, following the contraction and relaxation of the left ventricle open and close respectively.

Fig. 7B is a schematic bottom view illustrating the implantation of the valve replacement device according to an embodiment of the present application (taking the aortic valve as an example, a view viewed from the left ventricle toward the aorta). Corresponding to the embodiment shown in FIGS. 5B and 6B , in the embodiment shown in FIG. 7B , the outer frame 120 can be loosely bound/sewn to the inner frame 140 at a pair of proximal connecting parts 124 . corresponding position. As shown in FIG. 7B, after the implantation is completed and instruments such as the expansion device 400, the guide wire and the sheath are removed, the artificial valve 500 returns to a normal working state, and the internal stent 140 of the artificial valve fixing device 100 is expanded. inside.

Fig. 7C is a schematic bottom view illustrating a valve replacement device according to another embodiment of the present application after implantation (taking the aortic valve as an example, a view viewed from the left ventricle toward the aorta). Compared with the embodiment shown in FIG. 7B corresponding to the embodiment shown in FIGS. 5B and 6B, the embodiment shown in FIG. 7C may correspond to the embodiment shown in FIGS. The proximal connection portion 124 and the inner frame 140 are fastened to each other by methods such as welding, welding or tight binding/sewing of wires.

As shown in Fig. 5B, Fig. 5C, Fig. 6B, Fig. 6C, Fig. 7B and Fig. 7C, since the artificial valve fixing device 100 according to the present application does not rely on the radial support force between the outer support 120 and the annulus 300 to fix the artificial valve valve, and thus the outer diameter of the outer stent 120 after implantation may not be greater than the inner diameter of the annulus 300 of the native valve. In other words, after the implantation is completed, the outer diameter of the outer stent 120 can be just equal to the inner diameter of the annulus 300 of the native valve, so as to fit on the inner circumference of the annulus 300 without exerting a higher radial expansion force on the annulus 300. force. In this way, the stable positioning of the artificial valve fixing device 100 can be achieved without using a bracket with high rigidity and radial support force, and at the same time, the artificial valve fixing device 100 can retain better flexibility and adherence, thereby avoiding displacement At the same time, the risk of paravalvular leakage and damage to the valve ring is reduced. Alternatively, after implantation, the outer diameter of the outer stent 120 may also be slightly larger or slightly smaller than the inner diameter of the annulus 300 of the native valve. Preferably, after implantation, the outer diameter of the outer stent 120 ranges from 15 mm to 30 mm. Additionally, as shown in FIGS. 3-7C illustrating the implantation process, no axial (ie, distal or proximal) relative movement between inner stent 140 and outer stent 120 occurs during the implantation process. This simplifies the complexity of the interventional delivery device 200 and the complexity of the implantation process. In addition, since errors or misalignments that may be introduced by relative axial movement between the outer stent 120 and the inner stent 140 are avoided, the risk of implant failure is reduced.

It should be understood that various modifications may be made to the disclosed apparatus. Accordingly, the above description should not be taken as limiting, but merely exemplifications of embodiments of the present disclosure. Those skilled in the art will envision other modifications within the scope and spirit of the disclosure. For example, any and all features of one described embodiment can be suitably incorporated into another embodiment, and the benefits of the feature in one embodiment can be contemplated to be realized in another embodiment.

Claims (15)

1. A prosthetic valve fixation device for securing a prosthetic valve to a leaflet of a native valve, comprising:

an inner stent having an open proximal end, an open distal end, and a tubular sidewall extending along a longitudinal axis of the prosthetic valve fixation device between the open proximal end and the open distal end; and

an outer bracket having a three-dimensional annular shape extending in an axial direction in a bending manner and configured to be sleeved on a radially outer side of the inner bracket;

wherein the inner and outer stents are configured to clamp each leaflet of the native valve between the inner and outer stents to secure the prosthetic valve securing device to the leaflets of the native valve, an

Wherein the outer stent is connected to the inner stent in an axial direction along the longitudinal axis.

2. The prosthetic valve fixation device of claim 1, wherein the outer stent is configured to at least partially self-expand to return to an original radial dimension in the expanded state when the radial compressive force is removed from the outer stent after being radially compressed from the expanded state to a contracted radial dimension in the compressed state under the force of the radial compressive force.

3. The prosthetic valve fixation device of claim 2, wherein the outer diameter of the outer stent in the deployed state is 15mm to 30mm.

4. The prosthetic valve fixation device of claim 2, wherein the outer stent is made of a shape memory material or a superelastic material.

5. The prosthetic valve fixation device of claim 4, wherein the shape memory material is a shape memory nickel titanium alloy.

6. The prosthetic valve fixation device of claim 1, wherein the three-dimensional annular shape of the outer stent comprises at least two distal raised portions, each of the at least two distal raised portions for sandwiching a respective leaflet of the native valve between the respective distal raised portion and the inner stent.

7. The prosthetic valve fixation device of claim 5, wherein each of the at least two distal protruding portions has a "U" shape.

8. The prosthetic valve fixation device of claim 5, wherein each pair of adjacent distal protruding portions of the at least two distal protruding portions are connected together at a proximal connection portion.

9. The prosthetic valve fixation device of claim 8, wherein the proximal connection portion is fixedly connected to the inner stent.

10. The prosthetic valve fixation device of claim 1, wherein the outer stent is connected to the inner stent by wire stitching or binding, welding or fusion.

11. The prosthetic valve fixation device of claim 1, wherein the inner stent has a compressible lattice-like structure.

12. The prosthetic valve fixation device of claim 11, wherein the inner stent is configured to at least partially retain the compressed state when the radial compressive force is removed from the inner stent after being radially compressed from the expanded state to the compressed state under the radial compressive force.

13. The prosthetic valve fixation device of claim 12, wherein the inner stent is configured to expand radially from the compressed state to the expanded state when a radially outward force is applied to the inner stent with the inner stent in the compressed state.

14. The prosthetic valve fixation device of claim 11, wherein the material of the inner stent is cobalt chrome or stainless steel.

15. A valve replacement device, comprising:

the prosthetic valve fixation device according to any one of claims 1-14; and

a prosthetic valve of the type comprising a plurality of valve elements,

wherein the periphery of the prosthetic valve is secured to the inner surface of the inner stent.

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