WO2022078525A1

WO2022078525A1 - Interventional mitral valve stent

Info

Publication number: WO2022078525A1
Application number: PCT/CN2021/129991
Authority: WO
Inventors: 钟生平; 靳永富
Original assignee: 金仕生物科技（常熟）有限公司
Priority date: 2020-10-12
Filing date: 2021-11-11
Publication date: 2022-04-21
Also published as: CN112402058A

Abstract

An interventional mitral valve stent, comprising an upper flap portion (11) and a leaflet suspension portion (12), the upper flap portion (11) being connected above the leaflet suspension portion (12), and the stiffness of the upper flap portion (11) being less than that of the leaflet suspension portion (12). By means of the stiffness of the upper flap portion (11) of the valve stent being less than that of the leaflet suspension portion (12), the softer upper flap portion (11) is enabled to fully fit the human mitral valve, and adopt the natural shape of the human mitral valve, thereby effectively reducing the occurrence of mitral regurgitation, and accelerating the endothelialization after surgery, so that the interventional valve can stably operate in the body. The leaflet suspension portion (12) has a larger stiffness, so that the reliability of the fixation of the leaflet can be improved, the normal work of the interventional valve is ensured, and the service life is prolonged.

Description

Interventional mitral valve stent

technical field

The present application relates to the technical field of medical devices, and in particular, to an interventional mitral valve stent.

Background technique

Since the human mitral valve orifice is generally saddle-shaped, its front, back, left and right are not in the same plane, although these factors have been fully considered in the design of the interventional mitral valve, so that the upper part of the interventional valve can be aligned with the human mitral valve. The valve orifice is fitted as much as possible to reduce paravalvular leakage and endothelialization as soon as possible, so that the interventional valve can be integrated with the human body. However, due to the great individual differences in the human body, it is difficult for a stereotyped product to adapt to each individual shape, which may cause paravalvular leakage, inability to endothelialize or the valve cannot be integrated with the human body as a whole. , the interventional valve may be displaced or detached from the valve opening due to improper force, resulting in irreversible consequences.

Since the human aorta is very close to the mitral valve, there is only a layer of curtain separated. During the opening of the aortic valve and the closing of the mitral valve, the curtain is pushed to the side of the mitral valve by the blood, so that the aortic inflow channel is more unobstructed. to reduce blood flow resistance. However, if the valve opening of the interventional valve is too rigid, the curtain cannot be pushed to the side of the interventional valve, resulting in poor hemodynamics of the aortic valve. However, if the part connected to the valve leaflet on the stent of the interventional valve is too soft, it will cause unstable fixation of the valve leaflet, which affects the normal operation of the interventional valve and the lifespan of the interventional valve.

For this reason, some existing manufacturers design the interventional valve into a two-layer stent, the inner layer is used for fixing the valve leaflets, which is relatively rigid, and the outer layer is used for fixing with the human body, which is relatively soft. However, this kind of valve is large in size and needs to be implanted through a larger delivery system, which makes the surgical trauma larger, and at the same time, the opening area of the valve is small, which also has a certain impact on the hemodynamics.

Application content

The present application relates to an interventional mitral valve stent, which can realize natural shaping according to the shape of the valve orifice of the human body through one layer of the valve frame, so as to ensure the stable hemodynamics while the valve is working normally.

The purpose of the present application is to provide an interventional mitral valve stent, which includes a valve upper part and a leaflet suspension part, the valve upper part is connected above the valve leaflet suspension part, and the valve upper part has a lower stiffness than the valve upper part. Stiffness of the leaflet suspension to reduce the incidence of regurgitation and accelerate postoperative endothelialization;

The upper part of the valve and the suspension part of the valve leaflet are both mesh structures, a plurality of mesh holes are arranged in the mesh structure, and a connecting beam is formed between two adjacent mesh holes;

The total cross-sectional area of the connecting beam on the upper part of the valve is smaller than the total cross-sectional area of the connecting beam on the leaflet suspension part.

In a possible implementation manner, the ratio between the total cross-sectional area of the connecting beam on the upper part of the valve and the total cross-sectional area of the connecting beam on the leaflet suspension portion ranges from 0.3 to 0.7.

In a possible implementation manner, the thickness of the connecting beam in the leaflet suspension part is not less than the thickness of the connecting beam on the upper part of the valve.

In a possible implementation manner, the width of the connecting beam of the leaflet suspension part is not less than the width of the connecting beam on the upper part of the valve.

In a possible implementation manner, the width or thickness of the connecting beam on the upper portion of the valve and the width or thickness of the connecting beam on the leaflet suspension portion gradually transition between the upper valve portion and the leaflet suspension portion .

In a possible implementation manner, the number of connecting beams of the leaflet suspension part is not less than the number of connecting beams of the upper part of the valve.

In a possible implementation, the height of the upper part of the flap is 3-8 mm.

The technical solution provided by this application can achieve the following beneficial effects:

The interventional mitral valve stent provided by the present application is a single-layer valve stent. The single-layer valve stent has better elastic deformation ability. Compared with the existing double-layer valve stent, the single-layer valve stent is compressed after compression. With a smaller volume, it can be more easily loaded into the delivery system and implanted into the human body through the delivery system. At the same time, since the volume of the interventional valve with the single-layer valve holder provided in this embodiment is reduced, the enlargement of the surgical trauma is avoided, and the opening area of the interventional valve is relatively increased, which is beneficial to the stability of the hemodynamics.

In addition, by making the stiffness of the upper portion of the valve on the valve support smaller than that of the leaflet suspension portion, the upper portion of the valve is made softer, while the stiffness of the leaflet suspension portion is relatively large and less deformable than the upper portion of the valve. In the process of implantation into the human body, the interventional valve can be pulled from the atrium to the ventricle through the delivery system, so that the upper part of the softer valve can be fully fitted with the human valve, and naturally shaped according to the shape of the human valve, which can effectively reduce The occurrence of regurgitation and accelerated postoperative endothelialization enable the interventional valve to work stably in vivo.

In addition, by making the upper part of the valve relatively small, the upper part of the valve can have relatively strong elastic deformation ability, so that the curtain can be more easily pushed by the blood to the side of the intervention valve, ensuring the aortic blood flow Dynamic stability. At the same time, by making the valve leaflet suspension part have greater rigidity relative to the upper part of the valve, the valve leaflet suspension part can be relatively less deformed, thereby improving the reliability of the valve leaflet fixation, ensuring the normal operation of the interventional valve and prolonging the use of the valve. life.

It is to be understood that the foregoing general description and the following detailed description are exemplary only and do not limit the application.

Description of drawings

1 is a schematic structural diagram of an interventional mitral valve stent provided in an embodiment of the present application;

2 is a schematic structural diagram of an interventional mitral valve stent after deployment provided by an embodiment of the present application;

Fig. 3 is the side view of Fig. 2;

4 is a schematic structural diagram of an interventional mitral valve stent after deployment provided by another embodiment of the present application;

Fig. 5 is the side view of Fig. 4;

6 is a schematic structural diagram of an interventional mitral valve stent after deployment provided by another embodiment of the present application;

FIG. 7 is a side view of FIG. 6 .

Reference number:

1-Valve stent;

11-petal upper part;

12 - leaflet suspension;

13 - connecting beam;

14-mesh;

h - height;

b1-thickness;

b2-thickness;

c1 - width;

c2 - width.

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the application and together with the description serve to explain the principles of the application.

Detailed ways

In order to make the purpose, technical solutions and advantages of the present application more clearly understood, the present application will be described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application, but not to limit the present application.

In the description of this application, unless otherwise clearly specified and limited, the terms "first" and "second" are only used for the purpose of description, and should not be construed as indicating or implying relative importance; unless otherwise specified or explained , the term "multiple" refers to two or more; the terms "connection" and "fixed" should be understood in a broad sense, for example, "connection" can be a fixed connection, a detachable connection, or an integral Connection, or electrical connection; either directly or indirectly through an intermediary. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific situations.

In the description of this specification, it should be understood that the directional words such as "upper" and "lower" described in the embodiments of the present application are described from the perspective shown in the drawings, and should not be construed as a description of the embodiments of the present application. limited. Also, in this context, it should also be understood that when an element is referred to as being "on" or "under" another element, it can not only be directly connected "on" or "under" the other element, but also Indirectly connected "on" or "under" another element through intervening elements.

As shown in FIG. 1 to FIG. 7 , an embodiment of the present application provides an interventional mitral valve stent, which includes a valve upper part 11 and a leaflet suspension part 12 , the valve upper part 11 is connected above the valve leaflet suspension part 12 , and the valve The stiffness of the upper portion 11 is less than the stiffness of the leaflet suspension portion 12 .

Among them, stiffness refers to the ability of a material or structure to resist elastic deformation when it is stressed. In this embodiment, the stiffness is used to represent the ability of the upper valve portion 11 and the valve leaflet to resist elastic deformation under force, that is, the smaller the stiffness of the upper valve portion 11 or the valve leaflet, the weaker the ability to resist deformation, and the ability to elastically deform under force. the stronger.

As shown in FIG. 1 , the interventional mitral valve stent provided in this embodiment is a single-layer valve stent, and the single-layer valve stent has better elastic deformation ability. Compared with the existing double-layer valve stent, the single-layer valve stent The stent has a smaller volume after compression, and can be more easily loaded into the delivery system and implanted into the human body through the delivery system. At the same time, since the volume of the interventional valve with the single-layer valve holder provided in this embodiment is reduced, the enlargement of the surgical trauma is avoided, and the opening area of the interventional valve is relatively increased, which is beneficial to the stability of the hemodynamics.

In addition, in the valve holder provided in this embodiment, by making the stiffness of the upper valve part 11 relatively small, the upper valve part 11 is made softer, while the stiffness of the valve leaflet suspension part 12 is relatively large, which is relatively stiffer than the upper valve part 11 . In the process of implanting the interventional valve into the human body, the interventional valve can be pulled from the atrium to the ventricle through the delivery system, so that the softer upper part 11 of the valve can be fully fitted with the human body valve, and be naturally shaped according to the shape of the human valve orifice, thereby It can effectively reduce the occurrence of regurgitation and accelerate postoperative endothelialization, so that the interventional valve can work stably in the body.

Understandably, the human aorta is relatively close to the mitral valve, separated only by a curtain. When the aortic valve is open and the mitral valve is closed, the curtain is pushed by the blood to one side of the mitral valve, making the aorta The inflow channel is more open to reduce blood flow resistance. However, in the interventional mitral valve stent provided in this embodiment, the upper valve portion 11 can have relatively strong elastic deformation ability by making the upper valve portion 11 have a relatively small rigidity, so that during the mitral valve closing and the aorta opening period , which can make the curtain more easily pushed to the side of the intervention valve by the blood, and ensure the stability of the aortic hemodynamics.

In addition, the valve leaflet generally needs to be fixed on the valve leaflet suspension portion 12 to realize the connection between the valve leaflet and the valve frame. If the valve leaflet suspension portion 12 has the same smaller stiffness as the valve upper portion 11, the valve leaflet suspension portion 12 will be relatively small. Soft, it is not conducive to the connection and fixation of the valve leaflets, and it is also not conducive to the effective sealing of the valve leaflet to the intervention valve passage during the working process.

For this reason, in this embodiment, by making the leaflet suspension portion 12 have greater rigidity relative to the upper portion 11 of the valve, the leaflet suspension portion 12 can be relatively less deformed, thereby improving the reliability of the fixation of the valve leaflet and ensuring that the valve leaflet is fixed. The normal operation of the interventional valve and the extended service life.

Among them, as shown in FIG. 1 , the upper part 11 of the valve and the hanging part 12 of the valve leaflet are both mesh structures, a plurality of mesh holes 14 are arranged in the mesh structure, and a connecting beam 13 is formed between two adjacent mesh holes 14 .

It should be noted that, in order to facilitate the deformation of the intervening mitral valve stent, the shape of the mesh hole 14 may be a rhombus. Wherein, the valve support 1 may be a memory alloy plate, such as a nickel-titanium alloy.

Wherein, the valve upper part 11 and the valve leaflet suspension part 12 can be integrally formed.

As a specific implementation manner, the total cross-sectional area of the connecting beams of the upper valve portion 11 is smaller than the total cross-sectional area of the connecting beams of the leaflet suspension portion 12 .

In a natural state, the whole of the valve support 1 presents a hollow columnar structure, and its cross-sectional shape can be D-shaped, oval or circular.

Therefore, by making the total cross-sectional area of the connecting beams of the upper valve portion 11 smaller than the total cross-sectional area of the connecting beams of the leaflet suspension portion 12, the amount of material used for the connecting beams 13 in the upper valve portion 11 can be relatively small, so that it is possible to The stiffness of the upper flap 11 is relatively low, while the softness is relatively enhanced. Relatively, the amount of material used for the connecting beam 13 in the leaflet suspension portion 12 is relatively large, so that the leaflet suspension portion 12 has a relatively high stiffness and a relatively strong ability to resist deformation.

As a specific implementation manner, the ratio between the total cross-sectional area of the connecting beams of the upper petal portion 11 and the total cross-sectional area of the connecting beams of the leaflet suspension portion 12 may range from 0.3 to 0.7. In this embodiment, the ratio may preferably be 0.4, 0.5 or 0.6.

In a specific embodiment, as shown in FIGS. 1 to 3 , the thickness b2 of the connecting beam 13 of the leaflet suspension portion 12 is not less than the radial thickness b1 of the connecting beam 13 of the upper portion 11 of the valve.

Wherein, the thickness b2 of all the connecting beams 13 in the leaflet suspension portion 12 may be greater than the thickness b1 of all the connecting beams 13 in the upper portion 11 of the valve; or the thickness b2 of a part of the connecting beams 13 in the leaflet suspension portion 12 may be greater than The thickness b1 of the connecting beam 13 in the upper petal 11 , and the thickness b2 of another part of the connecting beam 13 in the leaflet suspension 12 is equal to the thickness b1 of the connecting beam 13 in the upper petal 11 . Therefore, the material of the connecting beam 13 in the leaflet suspension portion 12 can be used in a relatively large amount, so that the stiffness of the leaflet suspension portion 12 is relatively high, and the ability to resist deformation is relatively strong. At the same time, the amount of material used for the connecting beam 13 in the upper flap 11 can be relatively small, so that the stiffness of the upper flap 11 can be relatively low, and the softness can be relatively enhanced.

It should be noted that, as shown in FIG. 2 and FIG. 3 , in this embodiment, the width and number of the connecting beams 13 in the upper flap 11 and the flap suspension 12 can be the same, and only by changing the upper flap 11 and the flap The thickness of the connecting beams 13 in the leaf suspension portion 12 can change the total cross-sectional area of the two connecting beams, thereby changing the stiffness of the valve upper portion 11 and the leaflet suspension portion 12 .

Of course, while changing the thickness of the connecting beams 13 in the upper valve portion 11 and the leaflet suspension portion 12, the width and quantity of the connecting beams 13 in the upper valve portion 11 and the valve leaflet suspension portion 12 can also be appropriately changed. The total cross-sectional area of the connecting beams of 11 is smaller than the total cross-sectional area of the connecting beams of the leaflet suspension portion 12 and the rigidity requirements of the two, which are not limited in this embodiment.

In another specific embodiment, as shown in FIGS. 4 and 5 , the width c2 of the connecting beam 13 of the leaflet suspension portion 12 is not less than the width c1 of the connecting beam 13 of the upper portion 11 of the valve.

Wherein, in the unfolded state of the valve stent 1 , the width of the connecting beams 13 may be the distance between two adjacent mesh holes 14 separated by one connecting beam 13 .

Specifically, the width c2 of all the connecting beams 13 in the leaflet suspension portion 12 may be greater than the width c1 of all the connecting beams 13 in the upper portion 11 of the valve, as shown in FIG. 4 ; it may also be a part of the leaflet suspension 12 The width c2 of the connecting beam 13 is greater than the width c1 of the connecting beam 13 in the upper petal 11 , and the width c2 of another part of the connecting beam 13 in the leaflet suspension 12 is equal to the width c1 of the connecting beam 13 in the upper petal 11 . Therefore, the material of the connecting beam in the leaflet suspension portion 12 can be used in a relatively large amount, so that the stiffness of the leaflet suspension portion 12 is relatively high, and the ability to resist deformation is relatively strong. At the same time, the usage of the material of the connecting beam 13 in the upper flap 11 can be relatively small, so that the rigidity of the upper flap 11 can be relatively low, and the softness can be relatively enhanced.

It should be noted that, as shown in FIG. 4 and FIG. 5 , in this embodiment, the thickness and number of the connecting beams 13 in the upper petal 11 and the valve leaflet suspension 12 can be the same, and only by changing the upper petal 11 and the petals The width of the connecting beams 13 in the leaf suspension portion 12 can change the total cross-sectional area of the two connecting beams, thereby changing the stiffness of the valve upper portion 11 and the leaflet suspension portion 12 .

Of course, while changing the width of the connecting beams 13 in the upper valve portion 11 and the leaflet suspension portion 12, the thickness and quantity of the connecting beams 13 in the upper valve portion 11 and the valve leaflet suspension portion 12 can also be appropriately changed. The total cross-sectional area of the connecting beams of 11 is smaller than the total cross-sectional area of the connecting beams of the leaflet suspension portion 12 and the rigidity requirements of the two, which are not limited in this embodiment.

In yet another specific embodiment, as shown in FIGS. 6 and 7 , the number of connecting beams 13 of the leaflet suspension portion 12 is not less than the number of connecting beams 13 of the upper portion 11 of the valve.

Among them, as shown in FIG. 6 , when there are fewer connecting beams 13 in the upper part 11 of the flap, the number of meshes 14 formed between the connecting beams 13 is also less, and the area of the meshes 14 increases, resulting in the number of connecting beams 13 It is also less, that is, the amount of material of the connecting beams 13 is relatively reduced, and the rigidity is reduced; and when there are many connecting beams 13, the arrangement between the connecting beams 13 is denser, and the number of connecting beams 13 increases, that is, the material of the connecting beams 13 The amount is relatively increased, and the stiffness increases.

Specifically, the number of all connecting beams 13 in the leaflet suspension portion 12 may be greater than the number of all connecting beams 13 in the upper portion 11 of the valve, as shown in FIG. 6 ; it may also be that a part of the leaflet suspension 12 is connected The number of beams 13 is greater than the number of connecting beams 13 in the upper petal 11 , and the number of the other part of the connecting beams 13 in the leaflet suspension 12 is equal to the number of connecting beams 13 in the upper petal 11 . Therefore, the material of the connecting beam 13 in the leaflet suspension portion 12 can be used in a relatively large amount, so that the stiffness of the leaflet suspension portion 12 is relatively high, and the ability to resist deformation is relatively strong. At the same time, the usage of the material of the connecting beam 13 in the upper flap 11 can be relatively small, so that the rigidity of the upper flap 11 can be relatively low, and the softness can be relatively enhanced.

It should be noted that, as shown in FIG. 6 and FIG. 7 , in this embodiment, the thickness and width of the connecting beams 13 in the upper flap 11 and the flap suspension 12 can be the same, and only by changing the upper flap 11 and the flap The number of connecting beams 13 in the leaf suspension portion 12 can be used to change the total cross-sectional area of the connecting beams, thereby changing the stiffness of the valve upper portion 11 and the leaflet suspension portion 12 .

Of course, while changing the number of connecting beams 13 in the upper valve portion 11 and the valve leaflet suspension portion 12, the thickness and width of the connecting beams 13 in the upper valve portion 11 and the valve leaflet suspension portion 12 can also be appropriately changed. The total cross-sectional area of the connecting beams of 11 is smaller than the total cross-sectional area of the connecting beams of the leaflet suspension portion 12 and the rigidity requirements of the two, which are not limited in this embodiment.

Wherein, in a more preferred embodiment, when changing the stiffness of the upper petal 11 and the leaflet suspension 12 by changing the thickness, width or quantity of the connecting beams 13, the thickness or width of the connecting beams 13 can be There is a gradual transition between the upper portion 11 and the leaflet suspension portion 12, so that there is a gradual transition between the total cross-sectional area of the connecting beam of the upper portion 11 of the valve and the total cross-sectional area of the connecting beam of the leaflet suspension portion 12, without forming a strict alignment. The boundary line of the total cross-sectional area can make the force from the blood flow evenly transition on the valve support 1 and the valve leaflets, and ensure the stable operation of the interventional valve in the human body.

As a specific implementation, as shown in FIG. 2 , the height h of the upper portion 11 of the flap may be 3-8 mm. Therefore, the upper part 11 of the valve can be effectively fitted with the mitral valve orifice of the human body, so as to reduce paravalvular leakage and endothelialize as soon as possible, so that the intervention valve can be integrated with the human body. Wherein, the height h of the upper portion 11 of the flap may preferably be 4 mm, 5 mm, 6 mm, or 7 mm.

It should be noted that the interventional mitral valve stent provided in the embodiment of the present application may also be applicable to other valve positions.

The above descriptions are only preferred embodiments of the present application, and are not intended to limit the present application. For those skilled in the art, the present application may have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of this application shall be included within the protection scope of this application.

Claims

An interventional mitral valve stent, characterized in that it comprises a valve upper portion (11) and a valve leaflet suspension portion (12), wherein the valve upper portion (11) is connected above the valve leaflet suspension portion (12), so that the The stiffness of the valve upper part (11) is smaller than the stiffness of the valve leaflet suspension part (12), so as to reduce the incidence of regurgitation and accelerate postoperative endothelialization;

The valve upper part (11) and the valve leaflet suspension part (12) are both mesh structures, and a plurality of mesh holes (14) are arranged in the mesh structure, and between two adjacent mesh holes (14) A connecting beam (13) is formed;

The total cross-sectional area of the connecting beams of the valve upper part (11) is smaller than the total cross-sectional area of the connecting beams of the leaflet suspension (12).
The intervening mitral valve stent according to claim 1, characterized in that the total cross-sectional area of the connecting beam of the valve upper part (11) and the total cross-sectional area of the connecting beam of the leaflet suspension part (12) is the sum of the The ratio between them ranges from 0.3 to 0.7.
The stent for interventional mitral valve according to claim 1, characterized in that the thickness (b2) of the connecting beam (13) of the leaflet suspension (12) is not less than the connecting beam of the upper part of the valve (11) (13) Thickness (b1).
The interventional mitral valve stent according to claim 3, characterized in that, the width (c2) of the connecting beam (13) of the leaflet suspension (12) is not smaller than the connecting beam of the valve upper part (11) (13) width (c1).
The intervening mitral valve stent according to claim 4, wherein the width or thickness of the connecting beam on the upper part of the valve and the width or thickness of the connecting beam on the suspension part of the valve leaflet are the same as the width or thickness of the connecting beam on the upper part of the valve and the upper part of the valve. There is a gradual transition between the leaflet suspensions.
The interventional mitral valve stent according to claim 1, characterized in that, the number of connecting beams (13) of the leaflet suspension (12) is not less than the connecting beams (13) of the valve upper part (11) )quantity.
The interventional mitral valve stent according to any one of claims 1-5, characterized in that, the height (h) of the upper part of the valve (11) is 3-8 mm.