CN215019734U - Heart valve prosthesis device - Google Patents

Abstract

The utility model discloses a heart valve prosthesis device, including the frame construction that is used for bearing artificial valve leaf and cover the sealing mechanism who locates the frame construction surface, wherein, sealing mechanism includes that at least one deck has the first sealing member and the at least one deck second sealing member of imbibition ability, and the frame construction lateral surface is located in the second sealing member cover, and second sealing member surface is located in the first sealing member cover, wherein, has expanded form behind the first sealing member imbibition. The heart valve prosthesis device of the utility model is used for replacing the native valve, the sealing mechanism has the sealing function, if the surface of the first sealing element contacted with the tissue has seepage, the first sealing element can absorb liquid and expand, the volume is enlarged, the auxiliary sealing is realized, and the further leakage is prevented; and the first sealing element becomes flexible after imbibing and expanding, and the expanded shape can be matched with the irregular shape of the natural valve ring. Furthermore, the hydrophilic nature of the first sealing member also facilitates adhesion and proliferation of endothelial cells, thereby facilitating endothelialisation.

Description

Heart valve prosthesis device

Technical Field

The utility model relates to the technical field of medical equipment, in particular to a heart valve prosthesis device for replacing native valves.

Background

The heart contains four chambers, the left atrium and left ventricle being located on the left side of the heart, and the right atrium and right ventricle being located on the right side of the heart. A ventricular inflow channel is formed between the atrium and the ventricle, a left ventricular outflow channel is formed between the left ventricle and the aorta, and a right ventricular outflow channel is formed between the right ventricle and the pulmonary artery. Valves with the function of 'one-way valves' are arranged at the inflow channel and the outflow channel of the chamber, so that the normal flow of blood in the heart cavity is ensured. When a problem occurs with the valve, the hemodynamics of the heart change and the heart functions abnormally, which is called valvular heart disease.

With the development of socioeconomic and the aging of population, the incidence rate of valvular heart disease is obviously increased, and researches show that the incidence rate of valvular heart disease of the old people over 75 years old is up to 13.3%. At present, the traditional surgical treatment is still the first treatment method for patients with severe valvular diseases, but for the patients with advanced age, complicated multiple organ diseases, chest-open operation history and poor cardiac function, the traditional surgical treatment has high risk and high death rate, and some patients even have no operation chance. The transductal replacement/repair has the advantages of no need of thoracotomy, small wound, quick recovery of patients and the like, and is widely concerned by experts and scholars.

Despite the rapid advances in the field of transcatheter delivery of prosthetic valves in recent years, there remain several challenges, such as leakage between the implanted valve prosthesis and the surrounding native tissue, that need to be addressed. Minimally invasive percutaneous heart valve replacement typically does not involve actual physical removal of the diseased or injured heart valve, but rather delivers the stented valve prosthesis in a compressed condition to the native valve site. At the valve site, the prosthetic valve is expanded to its working state within the diseased valve. The calcified or diseased native leaflets are pressed against the sidewalls of the native valve by the radial force of the prosthetic valve stent. This can be a source of paravalvular leakage (PVL) as calcified leaflets do not fit perfectly to the shape of the stent.

In addition, significant pressure gradients across the valve can also cause leakage of blood through gaps between the implanted prosthetic valve and calcified anatomy.

SUMMERY OF THE UTILITY MODEL

The utility model provides a heart valve prosthesis device, which can solve the defects in the prior art.

The technical scheme of the utility model as follows:

a heart valve prosthesis device comprises a frame structure for bearing artificial valve leaflets and a sealing mechanism covering the surface of the frame structure, wherein the sealing mechanism comprises at least one layer of first sealing element with imbibition capability and at least one layer of second sealing element, the second sealing element covers the outer side surface of the frame structure, the first sealing element covers the outer side surface of the second sealing element, and the first sealing element has an expanded shape after imbibition.

The utility model discloses a heart valve false body device is used for replacing the native valve of pathological change, and the frame construction is peripheral side bears artifical valve leaf, and frame construction's periphery side is attached in native tissue week side. The sealing mechanism plays a sealing role, furthermore, the outermost side of the sealing mechanism is configured to be a first sealing element, if liquid seepage occurs on the surface of the first sealing element, which is in contact with the tissue, the first sealing element can absorb liquid and expand, the volume is increased, sealing is assisted, and further leakage is prevented. Moreover, the first sealing member becomes flexible upon imbibing expansion thereof, and the expanded shape can conform to the irregular shape of the native valve annulus to fill the gap between the prosthetic device and the tissue. Furthermore, the hydrophilic nature of the first sealing member also facilitates adhesion and proliferation of endothelial cells, thereby facilitating endothelialisation.

In some embodiments, the frame structure includes a first frame portion affixed to native tissue, the first frame portion including an inflow end and an outflow end at both ends, and an intermediate section between the inflow end and the outflow end, the sealing mechanism being disposed in the intermediate section of the first frame portion. Wherein, this frame construction is single-layer frame construction, and artificial valve leaf is fixed in the interlude of first frame portion, therefore this department structure needs to have certain rigidity, and this makes the interlude difficult to laminate with the tissue, and after the implantation, blood easily flows out along unexpected direction, and it leaks to cause the perivalvular to flow out to pass the interlude from prosthetic devices center. The sealing mechanism arranged in the middle section can play a role in sealing, so that the problem of valve leakage is solved.

In some embodiments, the frame structure comprises a first frame portion and a second frame portion disposed axially inward of the first frame portion with an annular gap disposed therebetween, the first frame portion comprising an inflow end and an outflow end at each end, and an intermediate section between the inflow end and the outflow end, the sealing mechanism being disposed at the intermediate section of the first frame portion; the annular gap is provided with a third seal connecting the first frame part and the second frame part, the third seal and the sealing mechanism closing the annular gap, thereby forming an annular space allowing blood to flow in and preventing thrombus from flowing out.

The frame structure is a double-layer frame structure, the first frame part is attached to tissues for anchoring, the artificial valve leaf is fixed to the inner peripheral side of the second frame part to form an inner-outer sleeved structure, and an annular gap is formed between the outer peripheral side of the second frame part and the inner peripheral side of the first frame part. The third seal may be provided by stitching, secured to the inflow end of the first frame portion, across the annular gap, and secured to the second frame portion. The third sealing element may be a single piece of material or may be formed by splicing a plurality of pieces of material, and at the outflow end near the first frame part, the third sealing element covers the end of the first frame part and the end of the second frame part, so as to form a closed annular space.

According to the double-layer frame structure, the expected flowing direction of blood flows from one end of the second frame part to the other end, but in practical application, the blood can generate unexpected flow, such as flowing into the annular gap or flowing out from the middle section of the first frame part, the third sealing element is matched with the sealing mechanism, thrombus can be trapped in the annular space, the sealing mechanism arranged at the middle section of the first frame part can play a role in preventing the unexpected flow of the blood, the paravalvular leakage is prevented, and the stability, the safety and the effectiveness of the valve device are further improved.

In some embodiments, the sealing mechanism comprises a layer of the second seal, wherein the second seal is made of a non-permeable material. The second sealing piece made of non-permeable materials is matched with the first sealing piece, so that the first sealing piece can be helped to fix leaked blood, perivalvular leakage is prevented, the blood is prevented from permeating the first frame portion, and free thrombus is caused.

In some embodiments, the sealing mechanism includes at least two layers of second sealing members disposed on the lateral side and the medial side of the first frame portion. Double-deck second sealing member can play effective sealedly, cooperates first sealing member simultaneously, can further prevent the valve perivalvular leakage.

In some embodiments, the second seal is made of a permeable material such that blood can penetrate one layer of the second seal, clot to form thrombus in the sandwiched region of the two layers of the second seal, and be trapped between the two layers of the second seal.

In some embodiments, the sealing mechanism comprises at least two layers of the first sealing member, wherein at least one layer of the first sealing member is disposed between two adjacent layers of the second sealing member. If blood permeates between the double-layer second sealing elements, the first sealing element absorbs liquid and expands, on one hand, the blood is promoted to form microcapsules to reduce paravalvular leakage, and on the other hand, the first sealing element fixes the blood and keeps in an interlayer of the second sealing element to prevent thrombus from flowing out and causing embolism risk. Therefore, through the cooperation of at least two layers of first sealing member and second sealing member, can effectively prevent the perivalvular leakage, reduce the embolism risk simultaneously.

In some embodiments, the third seal surface is provided with a liquid-absorbent polymer coating on the side of the annular gap proximal the outflow end of the first frame part. The provision of the third seal reduces the unintended flow of blood, which can be absorbed by the polymeric coating when penetrating the third seal towards the annular gap, promoting the formation of microcapsules of blood, which are retained in the coating or in the annular space, preventing the flow of thrombus out of the annular space, and the third seal, the imbibed polymeric coating, the sealing means and the thrombus-filled annular space can serve as a potting for the inner layer structure of the valvular prosthesis, further stabilizing the valvular prosthesis.

In some embodiments, the polymer coating is made of a hydrophilic polymer material selected from the group consisting of: at least one of polyethylene oxide, polyvinyl alcohol, polyacrylic acid, polypropylene fumaric acid-co-ethylene glycol and polypeptide, agarose, alginate, chitosan, collagen, fibrin, gelatin, hyaluronic acid, polyhydroxyethyl methacrylate, poly-2-hydroxyethyl methacrylate and their copolymers, polyvinylpyrrolidone, poly-N-vinylpyrrolidone hydrogel, poly-2-hydroxyethyl methacrylate/poly-N-vinylpyrrolidone copolymer, polyacrylamide.

In some embodiments, the polymer coating is formed by spraying, electrospinning, or rolling.

In some embodiments, the first sealing member is made of a hydrophilic polymer material selected from the group consisting of: at least one of polyethylene oxide, polyvinyl alcohol, polyacrylic acid, polypropylene fumaric acid-co-ethylene glycol and polypeptide, agarose, alginate, chitosan, collagen, fibrin, gelatin and hyaluronic acid, polyhydroxyethylmethacrylate, poly-2-hydroxyethylmethacrylate (p-HEMA) and copolymers thereof, polyvinylpyrrolidone (PVP), poly-N-vinylpyrrolidone (pNVP) hydrogel, poly-2-hydroxyethylmethacrylate (p-HEMA)/poly-N-vinylpyrrolidone (pNVP) copolymer, polyacrylamide (pAM).

In some embodiments, the first sealing element is a coating layer coated on the surface of the second sealing element, and the coating layer is formed by spraying, electrospinning or rolling.

Compared with the prior art, the beneficial effects of the utility model are as follows:

first, the utility model discloses a heart valve prosthesis device is used for replacing the native valve of pathological change, sealing mechanism plays sealed effect, and is further, and this sealing mechanism's the outside configuration is first sealing member, if the surface of first sealing member and tissue contact the weeping appears, first sealing member can imbibition inflation, and the volume grow is supplementary sealed, prevents further seepage. Moreover, the first sealing member becomes flexible upon imbibing expansion thereof, and the expanded shape can conform to the irregular shape of the native valve annulus to fill the gap between the prosthetic device and the tissue. Furthermore, the hydrophilic nature of the first sealing member also facilitates adhesion and proliferation of endothelial cells, thereby facilitating endothelialisation.

Secondly, the double-layer frame structure of the heart valve prosthesis device of the utility model can distribute the functions of bearing the artificial valve leaflet, bearing anchoring, sealing and the like to different frames, thereby achieving the purposes of not influencing the normal operation of other structures of the heart and better exerting the implantation treatment function; the third sealing member is arranged to reduce the unexpected flow of blood, when the surface of the side of the third sealing member near the outflow end is provided with the polymer coating, when blood penetrates through the third sealing member and flows to the annular gap, the blood is absorbed by the polymer coating to promote the blood to form microcapsules and is retained in the coating or the annular space, and the third sealing member, the imbibed polymer coating and the annular space filled with thrombus can be used for encapsulating the inner layer structure of the valve prosthesis, so that the valve prosthesis is further stabilized.

Of course, it is not necessary for any particular product to achieve all of the above-described advantages at the same time.

Drawings

Fig. 1 is a schematic structural view of a heart valve prosthesis device according to example 1 of the present invention;

fig. 2 is a schematic structural view of a first frame part according to embodiment 1 of the present invention;

fig. 3 is a schematic structural view of a heart valve prosthesis device according to embodiment 2 of the present invention.

Detailed Description

The utility model provides a heart valve prosthesis device, which solves the problem of valve leakage by arranging a sealing mechanism. The following embodiments all take mitral valve prosthesis as an example, and it should be noted that the heart valve prosthesis device of the present invention is also applicable to aortic, tricuspid or pulmonary valve.

In the present invention, it should be noted that the "inner side" refers to a side close to the axial center of the valve prosthesis, and the "outer side" refers to a side away from the axial center of the valve prosthesis.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplification of description, but do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art.

As used in this specification, the singular forms "a," "an," and "the" include plural referents unless the content clearly dictates otherwise. As used in this specification, the term "or" is generally employed in its sense including "and/or" unless the content clearly dictates otherwise.

The present invention will be further described with reference to the following specific examples.

Example 1

The present embodiment provides a mitral valve prosthesis 100, as shown in fig. 1, the mitral valve prosthesis 100 includes a frame structure 110 for carrying a prosthetic leaflet 130, and a sealing mechanism 120 disposed on a surface of the frame structure 110, wherein the sealing mechanism 120 includes at least one layer of a first sealing member 121 having imbibition capability and at least one layer of a second sealing member 122, the second sealing member 122 is disposed on an outer side of the frame structure 110, the first sealing member 121 is disposed on a surface of the second sealing member 122, and the first sealing member 121 has an expanded configuration after imbibition.

The frame structure can provide several functions for heart valve prosthesis 100, including serving as a main structure, an anchoring structure (including fluke structures to capture or puncture leaflets, etc.), a support to carry inner prosthetic leaflets 130, a seal to inhibit paravalvular leakage between mitral valve prosthesis 100 and the native valve, an attachment structure (hangers or fixation ears) to a delivery system, and so forth. The frame structure may be a biocompatible metal frame or a laser cut solid metal tube made of, for example, nitinol, titanium alloy, cobalt chromium alloy, MP35n, 316 stainless steel, L605, Phynox/Elgiloy, platinum chromium, or other biocompatible metals as known to those skilled in the art. Preferably, it is made of a shape memory alloy, but alternatively, it may comprise an elastically or plastically deformable material, such as a balloon expandable, or may be a shape memory alloy that responds to temperature changes to transition between a contracted delivery state and an expanded deployed state. Alternatively, the frame structure 110 may be constructed from braided wire or other suitable material.

The prosthetic leaflets 130 are dynamically switched between open and closed states in which the prosthetic leaflets 130 coapt or come together in sealing abutment. The prosthetic leaflet 130 can be formed from any suitable material or combination of materials. In some embodiments, the biological tissue may be selected, for example, a chemically stable tissue from a heart valve of an animal (e.g., porcine), or a pericardial tissue of an animal, such as bovine (bovine pericardium) or ovine (ovine pericardium) or porcine (porcine pericardium) or equine (equine pericardium), preferably bovine pericardial tissue. The artificial leaflet 130 may also be made of small intestine submucosal tissue. In addition, synthetic materials may also be used for the artificial leaflet 130. Such as expanded polytetrafluoroethylene or polyester. Optionally, thermoplastic polycarbonate polyurethane, polyether polyurethane, segmented polyether polyurethane, silicone-polycarbonate polyurethane, and ultra-high molecular weight polyethylene are also included. Additional biocompatible polymers can optionally include polyolefins, elastomers, polyethylene glycols, polyethersulfones, polysulfones, polyvinylpyrrolidones, polyvinyl chlorides, other fluoropolymers, silicone polyesters, siloxane polymers and/or oligomers, and/or polylactones, and block copolymers using the same. Optionally, leaflets 130 have surfaces treated with (or reacted with) anticoagulant, including but not limited to heparinized polymers.

When the valve prosthesis 100 is deployed within the annulus of a native heart valve, the frame structure 110 expands within the native leaflets of the patient's defective native valve, thereby holding the native leaflets in a permanently open state (against the sidewalls). The native annulus may include surface irregularities on its inner surface, and thus one or more gaps may exist or may be formed between the periphery of the valve prosthesis 100 and the native annulus. For example, there may be calcium deposits on the native leaflets and/or there may be a shape difference between the native heart valve annulus and the prosthesis 100. More particularly, some native valve annuluses are not perfectly circular, but rather have a concavity corresponding to the commissure points of the native leaflets (e.g., the mitral annulus is saddle-shaped (or D-shaped or kidney-shaped), with both horizontal and vertical planes being subject to movement and morphological changes). Thus, a prosthesis having a substantially circular cross-section does not provide an accurate fit to the native leaflets. For whatever reason, eventually these surface irregularities can make it difficult for the valve prosthesis to form a blood seal between the inner surfaces of the valve annulus, causing undesirable paravalvular leakage and/or regurgitation at the implantation site.

In the mitral valve prosthesis of the present embodiment, the sealing mechanism 120 performs a sealing function, and further, the outermost side of the sealing mechanism 120 is configured as the first sealing member 121, and if the surface of the first sealing member 121 contacting with the tissue is weeping, the first sealing member 121 can absorb liquid to expand, so that the volume of the first sealing member 121 increases, and the first sealing member assists in sealing and prevents further leakage. Furthermore, the first sealing member 121 becomes flexible after imbibing expansion, and the expanded shape can be matched with the irregular shape of the natural valve annulus, thereby solving the problem of sealing between the valve prosthesis and the inner surface of the valve annulus. Furthermore, the hydrophilic nature of the first seal 121 also facilitates adhesion and proliferation of endothelial cells, thereby facilitating endothelialization.

With continued reference to fig. 1 and 2, the frame structure 110 of the present embodiment is a single-layer frame, and includes a first frame part 111, the first frame part 111 is configured as a mesh-hole structure, and the artificial leaflet 130 is fixed to the inner peripheral side of the first frame part. The first frame part 111 comprises an inflow end 101 and an outflow end 103 at two ends, and a middle section 102 located between the inflow end 101 and the outflow end 103, the edge of the inflow end 101 expands outwards to be a horn mouth structure, after the mitral valve prosthesis 100 is implanted into a human body, the inflow end 101 is attached to the native mitral valve annulus of the heart to prevent the prosthetic valve from falling into the left ventricle from the left atrium, and the middle section 102 is used for bearing the prosthetic valve leaflet 130, and simultaneously supports on the calcified leaflet by virtue of the anchoring force of the frame structure 110 to play roles of anchoring and sealing. Blood flows in from the inflow end 101 of the first frame part and out from the outflow end 103.

In particular, the first frame portion 111 may be a cylindrical, elliptical, or other cylindrical structure having a cross-section that is circular, elliptical, D-shaped, saddle-shaped, petal-shaped, or a combination thereof, that may be compressed, loaded into a delivery device, released upon delivery to a target location, and self-expands to a target shape.

The artificial leaflet 130 of this embodiment is fixed to the middle section 102 of the first frame part 111, and therefore the structure needs to have a certain rigidity, which makes the middle section 102 difficult to adhere to the tissue, and after implantation, blood is liable to flow out in an unintended direction, i.e., from the center of the first frame part 111 through the middle section 102 to cause paravalvular leakage. Therefore, the sealing mechanism 120 of the present embodiment is disposed on the middle section 102 of the first frame part 111, and the first sealing member 121 serves as an auxiliary sealing member for filling the gap between the first frame part 111 and the valve annulus or native valve leaflet after imbibition and expansion, thereby preventing paravalvular leakage.

In some embodiments of the present invention, the,the sealing mechanism 120 includes a layer of the second sealing member 122, wherein the second sealing member 122 is made of a non-permeable material. The sealing mechanism 120 of the present embodiment is composed of a layer of the second sealing member 122 and the first sealing member 121 located outside the second sealing member 122, wherein the non-permeable material is used in combination with the first sealing member 121, which can help the first sealing member 121 to fix the leaked blood, prevent paravalvular leakage and prevent the blood from penetrating into the first frame part 111, and form thrombus capable of freely moving. Specifically, the non-permeable material has a permeability of less than 300ml/cm under 100-140 mmHg²Min, polyester fabric, PTFE, ePTFE, etc. can be selected. Of course, in alternative embodiments, the second seal 122 may be made of a permeable material.

In some embodiments, the sealing mechanism 120 includes at least two layers of the second sealing member 122, where the two layers of the second sealing member 122 are disposed on the lateral side and the medial side of the first frame portion 111. The sealing mechanism 120 of this embodiment comprises two-layer second sealing member 122 and the first sealing member 121 that is located the outside, and two-layer second sealing member 122 can play effective seal, cooperates first sealing member 121 simultaneously, can effectively prevent the valve perivalvular leakage.

Further, when the sealing mechanism 120 includes two layers of second sealing members 122, the second sealing members 122 are made of a permeable material, such that blood can penetrate one layer of the second sealing members 122, clot in the sandwiched region of the two layers of the second sealing members 122, and become trapped between the two layers of the second sealing members 122. Specifically, the permeable material has a permeability of more than 500ml/cm under 100-140 mmHg²Min, polyester fabric, PTFE, ePTFE, etc. can be selected.

Further, when the sealing mechanism 120 includes at least two layers of the second sealing members 122, at least one layer of the first sealing member 121 is disposed between two adjacent layers of the second sealing members 122. If blood permeates between the double-layer second sealing elements 122, the first sealing element 121 absorbs the liquid to expand, on one hand, the blood is promoted to form a microcapsule to reduce paravalvular leakage, and on the other hand, the first sealing element 121 fixes the blood to be kept in the interlayer of the second sealing element 122 to prevent thrombus from flowing out to cause embolism risk. Therefore, by the cooperation of the at least two layers of the first sealing member 121 and the second sealing member 122, paravalvular leakage can be effectively prevented, and simultaneously the risk of embolism is reduced.

The first sealing member 121 is made of a cross-linked hydrophilic macromolecular material forming a hydrogel polymer coating, the hydrogel polymer having a three-dimensional network structure, which is capable of swelling and contains about 20 wt% to about 95 wt% of water. Natural hydrogel polymers include fibrin, collagen, elastin, and the like. The hydrogel polymer may be a solution, gel, foam, or the like. In some cases, the hydrogel polymer is capable of absorbing greater than 50%, greater than 75%, greater than 100%, greater than 150%, etc., of water (or bodily fluid, e.g., blood) relative to its dry weight. Hydrogel polymers include polyethylene oxide, polyvinyl alcohol, polyacrylic acid, polypropylene fumaric acid-co-ethylene glycol and polypeptides, agarose, alginate, chitosan, collagen, fibrin, gelatin and hyaluronic acid, polyhydroxyethylmethacrylate, poly-2-hydroxyethylmethacrylate (p-HEMA) and copolymers thereof, polyvinylpyrrolidone (PVP), poly-N-vinylpyrrolidone (pNVP) hydrogel, pHEMA/pNVP copolymer, polyacrylamide (pAM), or other similar materials. Suitable materials can be selected according to actual clinical requirements.

Specifically, the first sealing element 121 is a coating layer coated on the surface of the second sealing element 122, and the coating layer is formed by spraying, electrostatic spinning, rolling or the like.

Further, the inflow end 101 and the outflow end 103 of the first frame portion 111 are provided with a skirt, which may be a single layer or a double layer, and the material of the skirt may be selected from knitted, woven, and braided polyester fabric, PTFE, ePTFE, etc., and the skirt mainly plays a role of sealing.

Specifically, the second sealing member 122 and the skirt are covered on the surface (inner side surface and/or outer side surface) of the first frame portion 111, and may be fixed to the frame structure by sewing.

Example 2

The present embodiment provides a mitral valve prosthesis, which comprises a frame structure 210 for carrying a prosthetic leaflet 230 and a sealing mechanism 220 disposed on a surface of the frame structure 210, wherein the frame structure 210 is used for supporting the prosthetic leaflet. The valve prosthesis of the present embodiment is similar to embodiment 1, except that the frame structure 210 of the present embodiment is a double-layered frame structure.

Due to the anatomically large annulus size of the mitral valve, the portion of the support body of the prosthetic valve implanted in the mitral valve to carry the prosthetic valve leaflet needs to be of a larger size, both in circumferential diameter and axial height, resulting in a larger size of the prosthetic structure under the valve after the prosthetic valve is implanted in the mitral valve, with a greater risk of damage to the sub-valvular structure of the native valve assembly. Meanwhile, the structure of the prosthesis under the valve is too large, so that the blood ejection function of the aorta is affected, and the left ventricular outflow tract is blocked. For some patients with mitral regurgitation, the valve of the patient has no calcified part, and the existing working principle of preventing the displacement of the prosthetic valve by using the radial supporting force generated between the prosthetic valve and the native valve cannot be adopted, so the prosthetic valve of the double-layer stent has better treatment effect. The double-layer mitral valve prosthesis can distribute the functions of bearing artificial valve leaflets, anchoring, sealing and the like to different single-layer valve components, thereby achieving the purposes of not influencing the normal operation of other structures of the heart and better playing the implantation treatment function.

Specifically, the frame structure 210 of the present embodiment includes a first frame portion 211 and a second frame portion 212, the second frame portion 212 is axially disposed inside the first frame portion 211, and an annular gap is disposed between the first frame portion 211 and the second frame portion 212. The first frame part 211 comprises an inflow end 201 and an outflow end 203 at both ends, and an intermediate section 202 between the inflow end 201 and the outflow end 203, and the sealing mechanism 220 is provided at the intermediate section 202 of the first frame part 211. The annular gap is provided with a third seal 240, the third seal 240 connects the first frame part 211 and the second frame part 212, the third seal 240 and the sealing mechanism 220 close the annular gap, thereby forming an annular space 250 which allows blood to flow in and prevents thrombus from flowing out.

The third sealing element 240 may be a whole skirt, or may be formed by splicing multiple skirt materials, the third sealing element 240 may be a single-layer structure, or may be a double-layer structure, and the skirt material is similar to that of the skirt in embodiment 1.

When the valve prosthesis 200 is placed in the annulus of a human heart valve, blood from the atrium can flow into and out of the annular gap between the first frame part 211 and the second frame part 212. Blood can clot to form a thrombus, which can be transported by the flow of blood during the circulatory pumping of the heart, causing vascular obstruction, and in severe cases cerebral thrombosis and even life-threatening events. By the cooperation of the third seal 240 and the sealing mechanism 220, thrombus formed when blood flows into the annular space is trapped within the annular space, thereby serving to reduce the risk of embolism. Meanwhile, the sealing mechanism 220 can effectively prevent the valve from leaking.

The sealing mechanism 220 of the present embodiment includes a second sealing member 222 covering the inner side surface and the outer side surface of the first frame portion 211, and a first sealing member 221 covering the surface of the second sealing member 222 and located outside the valve prosthesis 200. Of course, the second seal 222 may be provided in only one layer, such as on the inner or outer side of the first frame portion 211. Wherein, a layer of the first sealing member may also be disposed between the two layers of the second sealing members 222.

In some embodiments, the third sealing element 240 is provided with a liquid-absorbent polymer coating 241 on the surface, and the polymer coating 241 is located on the side of the annular gap near the outflow end 203 of the first frame part 211.

In this embodiment, a polymer coating 241 is added to the inner layer of the third seal 240 at the annular gap, where the inner layer is referred to as being located in the annular space. If blood penetrates into the annular space 250 and contacts the polymer coating 241, the polymer coating 241 will imbibe and expand, fixing the blood within the annular space 250 and preventing thrombus from flowing out and causing an embolism risk. The expanded polymer coating 241, the thrombus-filled annular space 250 can serve as a potting to the inner structure of the valve prosthesis 100 (including the inner first frame portion 211 and its skirt, the prosthetic valve leaflets) to further stabilize the valve prosthesis. In addition, the encapsulation formed by the sealing mechanism 220 and the annular space 250 can further improve stability.

Wherein, the polymer coating 241 is made of hydrophilic polymer material, and the hydrophilic polymer material is selected from: at least one of polyethylene oxide, polyvinyl alcohol, polyacrylic acid, polypropylene fumaric acid-co-ethylene glycol and polypeptide, agarose, alginate, chitosan, collagen, fibrin, gelatin and hyaluronic acid, polyhydroxyethylmethacrylate, poly-2-hydroxyethylmethacrylate (p-HEMA) and copolymers thereof, polyvinylpyrrolidone (PVP), poly-N-vinylpyrrolidone (pNVP) hydrogel, poly-2-hydroxyethylmethacrylate (p-HEMA)/poly-N-vinylpyrrolidone (pNVP) copolymer, polyacrylamide (pAM). The polymer coating is formed by spraying, electrostatic spinning or rolling and the like.

In this embodiment, the shape, structure, material, and molding manner of the first frame portion 211 and the second frame portion 212 are similar to those of the first frame portion 111 in embodiment 1, and the description thereof is omitted. The first frame portion 211 and the second frame portion 212 of the present embodiment may be identical in shape, structure, material, and molding method, or may be different.

In this embodiment, the first frame portion 211 and the second frame portion 212 are abutted at one end near the outlet end 203, specifically, at the side near the outlet end 203, the outer peripheral side of the second frame portion 212 abuts against the inner peripheral side of the first frame portion 211, and the two are connected and sealed by a skirt C, and the skirt C covers the bottom ends (near the outlet end) of the first frame portion 211 and the second frame portion 212, respectively. The first frame portion 211 is flared outward on the side close to the inflow end 201, and a predetermined gap is provided between the side close to the inflow end of the second frame portion 212 and the inner side of the first frame portion 211, so that the first frame portion 211 and the second frame portion 212 form the annular gap on the side close to the inflow end 201.

Of course, the first frame portion 211 and the second frame portion 212 may have a certain gap at one end near the outflow end 203, and be covered and connected by the skirt C.

In this embodiment, blood can flow into the annular space 250 from the third seal 240 above the annular gap and can flow out of the skirt on the side surface of the second frame portion 212, and thrombus is confined within the annular space, forming a potting.

In this embodiment, the annular gaps of the first frame portion 211 and the second frame portion 212 on the side close to the inflow end are continuous annular gaps along the circumferential direction, but of course, in some embodiments, the annular gaps may also be configured as discontinuous gaps along the circumferential direction or arc-shaped gaps along the circumferential direction, and the shape and size of the annular gaps are not limited in this embodiment.

While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not to be limited to the disclosed embodiment, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

The embodiments were chosen and described in order to best explain the principles of the invention and its practical application, to thereby enable others skilled in the art to best utilize the invention. In practical applications, the improvement and adjustment made by those skilled in the art according to the present invention still belong to the protection scope of the present invention. The technical features in the different embodiments above may be combined arbitrarily without conflict.

Claims (12)

1. A heart valve prosthesis device, which is characterized by comprising a frame structure for bearing a prosthetic valve leaflet and a sealing mechanism covering the surface of the frame structure, wherein,

the sealing mechanism comprises at least one layer of first sealing element with imbibition capability and at least one layer of second sealing element, the second sealing element is covered on the outer side surface of the frame structure, the first sealing element is covered on the outer side surface of the second sealing element, and the first sealing element has an expanded form after imbibition.

2. The heart valve prosthesis device of claim 1, wherein the frame structure comprises a first frame portion affixed to native tissue, the first frame portion comprising an inflow end and an outflow end at both ends, and an intermediate section between the inflow end and the outflow end, the sealing mechanism being disposed in the intermediate section of the first frame portion.

3. The heart valve prosthesis device of claim 1, wherein the frame structure comprises a first frame portion and a second frame portion disposed axially inward of the first frame portion, an annular gap being configured between the first frame portion and the second frame portion,

the first frame part comprises an inflow end and an outflow end which are positioned at two ends, and a middle section which is positioned between the inflow end and the outflow end, and the sealing mechanism is arranged at the middle section of the first frame part;

the annular gap is provided with a third sealing element which covers the inflow end of the first frame part and the second frame part, and the annular gap is closed by the third sealing element and the sealing mechanism, so that an annular space which allows blood to flow in and limits thrombus to flow out is formed.

4. The heart valve prosthetic device of claim 1, 2, or 3, wherein the sealing mechanism comprises a layer of the second seal, wherein the second seal is made of a non-permeable material.

5. The heart valve prosthesis device of claim 1, 2 or 3, wherein the sealing mechanism comprises at least two layers of second sealing members disposed on the outer and inner sides of the first frame portion.

6. The heart valve prosthetic device of claim 5, wherein the second seal is made of a permeable material.

7. The heart valve prosthetic device of claim 5, wherein at least one layer of the first seal is disposed between two adjacent layers of the second seal.

8. The heart valve prosthesis device of claim 3, wherein the third seal surface is provided with a liquid-absorbent polymer coating, the second polymer coating being provided on the annular gap on a side proximal to the outflow end of the first frame portion.

9. The heart valve prosthetic device of claim 8, wherein the polymer coating is made of a hydrophilic polymer material selected from the group consisting of: at least one of polyethylene oxide, polyvinyl alcohol, polyacrylic acid, polypropylene fumaric acid-co-ethylene glycol and polypeptide, agarose, alginate, chitosan, collagen, fibrin, gelatin, hyaluronic acid, polyhydroxyethyl methacrylate, poly-2-hydroxyethyl methacrylate and their copolymers, polyvinylpyrrolidone, poly-N-vinylpyrrolidone hydrogel, poly-2-hydroxyethyl methacrylate/poly-N-vinylpyrrolidone copolymer, polyacrylamide.

10. The heart valve prosthetic device of claim 9, wherein the polymer coating is formed by spraying, electrospinning, or rolling.

11. The heart valve prosthetic device of claim 1, 2, or 3, wherein the first seal is made of a hydrophilic polymer material selected from the group consisting of: at least one of polyethylene oxide, polyvinyl alcohol, polyacrylic acid, polypropylene fumaric acid-co-ethylene glycol and polypeptide, agarose, alginate, chitosan, collagen, fibrin, gelatin, hyaluronic acid, polyhydroxyethyl methacrylate, poly-2-hydroxyethyl methacrylate and their copolymers, polyvinylpyrrolidone, poly-N-vinylpyrrolidone hydrogel, poly-2-hydroxyethyl methacrylate/poly-N-vinylpyrrolidone copolymer, polyacrylamide.

12. The heart valve prosthesis device of claim 11, wherein the first seal is a coating applied to a surface of the second seal, the coating being formed by spraying, electrospinning, or rolling.

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