An artificial heart valve and its delivery system

Abstract

The present invention relates to the field of medical devices, and in particular to an artificial heart valve and a delivery system thereof, wherein the artificial heart valve comprises an outer stent and an inner stent, wherein the outer stent and the inner stent are detachably connected, or when the artificial heart valve is in use, the inner stent is placed inside the outer stent, and the inner stent is not connected to the outer stent, wherein the outer stent comprises an outer stent frame and a disposable valve leaflet arranged on the outer stent frame, and the inner stent comprises an inner stent frame and an artificial valve leaflet arranged in the inner stent frame. The delivery system comprises a delivery sheath, a guidewire cavity sleeved in the delivery sheath, and a stent catheter, wherein the stent catheter is configured to be suitable for connection with the artificial heart valve. The artificial heart valve and the delivery system thereof of the present invention reduce the delivery size of the delivery system, and improve the safety of implantation and the universality of the size.

Description

Technical Field

[0001] The present invention relates to the field of medical devices, and in particular to an artificial heart valve and a delivery system thereof. Background Art

[0002] Heart valves are membrane-like structures that can open and close inside the organs of humans or certain animals. Each person has four valves in their heart, namely the aortic valve connecting the left ventricle and the aorta, the pulmonary valve connecting the right ventricle and the pulmonary artery, the mitral valve connecting the left atrium and the left ventricle, and the tricuspid valve connecting the right atrium and the right ventricle. These heart valves all act as one-way valves, allowing blood to flow from one direction to another but not back.

[0003] With the development of social economy and the aging of population, the incidence of valvular heart disease has increased significantly. Studies have shown that the incidence of valvular heart disease in the elderly population over 75 years old is as high as 13.3%. At present, traditional surgical treatment is still the first choice for patients with severe valvular disease. However, for patients of advanced age, patients with multiple organ diseases, patients with a history of open-chest surgery, and patients with poor heart function, traditional surgical treatment has high risks and mortality rates, and some patients do not even have the opportunity for surgery. The tricuspid valve is the atrioventricular valve of the right heart, and its structure is similar to that of the mitral valve, including leaflets, valve rings, chordae tendineae, papillary muscles, and myocardium. Transcatheter tricuspid valve replacement / repair has the advantages of no need for open-chest surgery, less trauma, and faster patient recovery, and has received widespread attention from experts and scholars.

[0004] At present, tricuspid valve designs are divided into two types: double-layer stents and single-layer stents. For single-layer stents, it is often necessary to use a valve with a larger radius. The valve with a larger radius will bear greater blood pulsation pressure than the valve with a smaller radius during the cardiac cycle, and the larger valve force will have a greater impact on the fatigue strength of the stent. In addition, it is not easy for a single-layer stent to maintain the shape of the stent and valve during the cardiac cycle. The valve diameter of the double-layer stent is relatively small, and the bearing of the artificial valve leaflets and the functions of anchoring and sealing can be distributed to components of different layers, so as to achieve the purpose of not affecting the normal operation of other structures of the heart and better exerting the implantation treatment function. However, double-layer stents often face the problem of an overall delivery size (Profile) that is too large, which makes delivery difficult, resulting in a smaller range of applicable populations and safety hazards during use. Summary of the invention

[0005] In view of the above-mentioned shortcomings of the prior art, an object of the present invention is to provide an artificial heart valve and a delivery system thereof, so as to solve the problems in the prior art.

[0006] To achieve the above-mentioned purpose and other related purposes, the present invention provides an artificial heart valve, which includes an outer stent and an inner stent. The outer stent and the inner stent are detachably connected, or when the artificial heart valve is in use, the inner stent is placed inside the outer stent, and the inner stent is not connected to the outer stent. The outer stent includes an outer stent frame and a disposable leaflet arranged on the outer stent frame, and the inner stent includes an inner stent frame and an artificial leaflet arranged in the inner stent frame.

[0007] The present invention also provides a delivery system for an artificial heart valve, the delivery system comprising a delivery sheath, a guidewire cavity sleeved in the delivery sheath, and a stent catheter, wherein the stent catheter is configured to be suitable for connection with the artificial heart valve.

[0008] The present invention also provides a heart valve replacement system, which includes the artificial heart valve and the delivery system.

[0009] As described above, an artificial heart valve and its delivery system of the present invention have the following beneficial effects:

[0010] 1. When the assembled stent is loaded into the delivery system, it does not need to overlap radially like the traditional double-layer stent, so the size of the delivery system (profile) can be greatly reduced;

[0011] 2. A lower delivery system size (Profile) can reduce the resulting delivery risk, improve implant safety and universality of size.

[0012] 3. A lower profile can be adapted to a wider range of people, such as those with relatively small femoral veins.

[0013] 4. After the assembled stent is pressed and loaded into the delivery system, it has less rigidity than a traditional double-layer stent, making it easier for the stent to pass through tortuous blood vessels, such as the aortic arch. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 Shown is a schematic cross-sectional view of an artificial heart valve of the present invention.

[0015] Figure 2 Shown is a schematic cross-sectional view of the outer stent of the artificial heart valve of the present invention, wherein the shadow in the figure is the projection of the skirt.

[0016] Figure 3 Shown is a schematic cross-sectional view of an inner stent of an artificial heart valve of the present invention.

[0017] Figure 4-1 Shown is a cross-sectional schematic diagram of a delivery system for an artificial heart valve of the present invention.

[0018] Figure 4-2 A cross-sectional schematic diagram of another delivery system for an artificial heart valve of the present invention is shown.

[0019] Figure 4-3 A cross-sectional schematic diagram of another delivery system for an artificial heart valve of the present invention is shown.

[0020] Figure 4-4 A cross-sectional schematic diagram of another delivery system for an artificial heart valve of the present invention is shown.

[0021] Figure 5-1 Displayed as used Figure 4-1 Schematic diagram of the delivery system showing the procedure for implanting a prosthetic heart valve.

[0022] Figure 5-2 Displayed as used Figure 4-2 and Figure 4-3 Schematic diagram of the delivery system showing the procedure for implanting a prosthetic heart valve.

[0023] Figure 5-3 Displayed as used Figure 4-2 and Figure 4-4 Schematic diagram of the delivery system showing the procedure for implanting a prosthetic heart valve.

[0024] Component number description

[0025] 1 External bracket

[0026] 11 External support frame

[0027] 111 Flange

[0028] 111a First flange section

[0029] 111b Second flange section

[0030] 111c Third flange section

[0031] 112 Main body

[0032] 112a Inner wall

[0033] 112b outer wall

[0034] 113 Ear Grabbing

[0035] 12 Disposable leaflets

[0036] 13 Anchor

[0037] 2 Internal support

[0038] 21 Inner support frame

[0039] 211 Inflow segment

[0040] 212 outflow section

[0041] 22 Prosthetic valve leaflets

[0042] 23 Inner bracket skirt

[0043] 31 Delivery Sheath

[0044] 32 Guidewire Lumen

[0045] 33 Stent Catheter

[0046] 331 External Stent Catheter

[0047] 332 Stent Catheter

[0048] 33a Wide part

[0049] 34 Control Bend Sheath DETAILED DESCRIPTION

[0050] The following is a description of the implementation of the present invention by means of specific embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification.

[0051] See also Figure 1 to Figure 5-3 . It should be noted that the structures, proportions, sizes, etc. illustrated in the drawings in this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions for the implementation of the present invention, so they have no substantial technical significance. Any modification of the structure, change in the proportional relationship, or adjustment of the size should still fall within the scope of the technical content disclosed by the present invention without affecting the effects and purposes that can be achieved by the present invention. At the same time, the terms such as "upper", "lower", "left", "right", "middle" and "one" quoted in this specification are only for the convenience of description, and are not used to limit the scope of the implementation of the present invention. Changes or adjustments in their relative relationships should also be regarded as the scope of the implementation of the present invention without substantially changing the technical content.

[0052] like Figure 1 and 2 As shown, the present invention provides an artificial heart valve, which includes an outer support 1 and an inner support 2. The outer support 1 and the inner support 2 are detachably connected, or when the artificial heart valve is in use, the inner support 2 is placed inside the outer support 1, and the inner support 2 is not connected to the outer support 1. The outer support 1 includes an outer support frame 11 and a disposable leaflet 12 arranged on the outer support frame 11, and the inner support 2 includes an inner support frame 21 and an artificial leaflet 22 arranged in the inner support frame 21.

[0053] In one embodiment, the inner support frame 21 is cylindrical. The outer support 1 has a cylindrical space, so as to ensure that the inner support frame 21 can be sleeved therein.

[0054] In one embodiment, the outer support frame 11 includes a flange portion 111 , a main body portion 112 , and a gripping ear portion 113 which are connected in sequence.

[0055] After the artificial heart valve is implanted in the body, the flange portion 111 is placed in the atrium. The flange portion 111 and the gripping ear portion 113 together clamp the native tissue to achieve the effect of anchoring the valve.

[0056] In one embodiment, the flange portion 111 includes a first flange segment 111 a , a second flange segment 111 b , and a third flange segment 111 c that are sequentially connected.

[0057] In one embodiment, when the outer support frame 11 is placed vertically, the angle α between the second flange section 111b and the horizontal direction is -10° to 55°. That is, in the outer support frame 11, the angle between the second flange section 111b and the radial direction of the outer support frame 11 is -10° to 55°.

[0058] In one embodiment, the main body 112 includes an inner wall 112a and an outer wall 112b, and the inner wall 112a and the outer wall 112b are connected end to end to form a closed structure. Specifically, the wall near the central axis of the artificial heart valve is the inner wall 112a, and the wall far from the central axis of the artificial heart valve is the outer wall 112b. The inner wall 112a is used to support the inner stent 2. The outer wall 112b can form a certain amount of compression between the outer stent 1 and the native valve ring, so that the outer stent 1 forms a radial anchoring force between the atrioventricular chamber.

[0059] The closed structure of the main body 112 is hollow inside.

[0060] In one embodiment, the ear gripping portion 113 includes a first ear gripping section 113a, a second ear gripping section 113b, and a third ear gripping section 113c which are connected in sequence.

[0061] In one embodiment, when the outer support frame 11 is placed vertically, the angle β between the third gripping ear section 113c and the vertical direction is -15° to 15°, that is, the angle between the third gripping ear section 113c and the axial direction of the outer support frame 11 is -15° to 15°.

[0062] There is no specific limitation on other angles of the gripping portion 113, as long as the angle between the third gripping segment 113c and the vertical direction is maintained. The gripping portion 113 and the outer wall 112b may form a U-shaped space.

[0063] The grabbing ears 113 can hook the valve leaflets and pass through the chordae tendineae to prevent the external support 1 from circumferential rotation.

[0064] The external support 1 is anchored between the chambers by the flange portion 111 , the main body portion 112 and the gripping ear portion 113 .

[0065] In one embodiment, the disposable leaflet 12 is disposed on the inner wall 112a.

[0066] In one embodiment, the disposable leaflet 12 is composed of a polymer braid. The main function of the disposable leaflet 12 is to be used as a temporary artificial leaflet from the beginning of the release of the outer stent 1 to the end of the release of the inner stent 2 to prevent reflux. After the inner stent 2 is released, the disposable leaflet 12 is filled between the inner and outer stents, which can increase the friction between the inner and outer stents, thereby increasing the anchoring force; the disposable leaflet 12 is filled between the inner and outer stents to reduce leakage between the inner and outer stents; and it helps endothelialization. If the disposable leaflet 12 is not provided, when the artificial heart valve is implanted, severe reflux will occur between the beginning of the release of the inner stent and the completion of the release of the inner stent, which can easily cause heart failure.

[0067] In one embodiment, the outer bracket 1 further includes an outer bracket skirt, and the outer bracket skirt is at least provided on the surfaces of the flange portion 111 and the main body portion 112 .

[0068] The outer bracket skirt is covered on the surface of the flange part 111 and the main body part 112. The outer bracket skirt can be an integral structure, that is, the same outer bracket skirt is provided on the surface of the flange part 111 and the main body part 112 at the same time; the outer bracket skirt can also be a separate structure, that is, more than two outer bracket skirts are provided on the surface of the flange part 111 and the main body part 112 respectively.

[0069] The function of the external stent skirt is to block the flow between the atrioventricular chambers and assist endothelialization after the external stent 1 is implanted.

[0070] In one embodiment, the outer support 1 further includes an anchor 13, and the anchor 13 is disposed on the outer support frame 11. In a preferred embodiment, the anchor 13 is disposed on the inner wall 112a of the outer support frame 11. The specific location of the inner wall 112a is not specifically limited. In a preferred embodiment, the anchor 13 is disposed in the middle position of the inner wall 112a.

[0071] The anchor 13 can be a protrusion integrally formed with the inner wall 112a, or a separate component fixedly connected to the inner wall 112a. The material of the anchor 13 can be a biocompatible metal or synthetic material, etc., which is not limited by the present invention. In a preferred embodiment, the surface of the anchor 13 is uneven. The unevenness serves to provide an anchoring position and an anchoring force for the release of the inner stent 2.

[0072] The disposable valve leaflet 12 is arranged below the anchor 13. Such an arrangement can ensure that a cavity is not easily formed after the inner stent 2 is implanted, thereby reducing the risk of thrombosis; at the same time, it is convenient for sewing and helps prevent leakage from the ventricle to the atrium.

[0073] The inner support frame 21 includes an inflow section 211 and an outflow section 212. The inflow section 211 is a section for blood to flow from the atrium into the inner support 2, and the outflow section 212 is a section for blood to flow from the inner support 2 through the valve leaflets to the ventricle.

[0074] The material of the inner stent frame 21 is selected from nickel-titanium alloy or cobalt-chromium alloy. Nickel-titanium can expand by itself, while cobalt-chromium needs to be expanded with a ball.

[0075] The material of the artificial valve leaflet 22 is not particularly limited, and common or general materials in the prior art can be selected. In one embodiment, biological tissues such as chemically stable tissues from heart valves of animals (such as pigs) are selected, or pericardial tissues of animals such as cattle (bovine pericardium) or sheep (sheep pericardium) or pigs (pig pericardium) or horses (horse pericardium), preferably bovine pericardial tissue. In another embodiment, it can be made of submucosal tissue of the small intestine. In other embodiments, synthetic materials can be selected. For example, expanded polytetrafluoroethylene or polyester. Optionally, synthetic materials also include thermoplastic polycarbonate polyurethane, polyether polyurethane, segmented polyether polyurethane, silicone polyether polyurethane, silicone-polycarbonate polyurethane, and ultra-high molecular weight polyethylene. Synthetic materials also include biocompatible polymers, such as polyolefins, elastomers, polyethylene glycol, polyether sulfone, polysulfone, polyvinyl pyrrolidone, polyvinyl chloride, other fluorinated polymers, silicone polyesters, siloxane polymers and / or oligomers, and / or polylactones and block copolymers using them.

[0076] In one embodiment, an anticoagulant is provided on the surface of the artificial valve leaflet 22. The anticoagulant includes but is not limited to a heparinized polymer.

[0077] In one embodiment, the inner support 2 further comprises an inner support skirt 23 , and the position of the inner support skirt 23 is not limited, as long as the skirt can block the flow between the chambers. In one embodiment, the inner support skirt 23 is arranged on the inner surface of the inner support frame 21 .

[0078] In one embodiment, the artificial valve leaflets 22 are connected to the inner stent skirt 23. The inner stent skirt 23 provides a location for the artificial valve leaflets 22 to cling to.

[0079] The material of the outer stent skirt or the inner stent skirt 23 in the present invention is not particularly limited, and common or general materials in the prior art can be selected. Knitted, woven, braided polyester fabrics, PTFE, ePTFE and other materials can be selected. The outer stent skirt or the inner stent skirt 23 mainly plays a sealing role to prevent regurgitation or paravalvular leakage.

[0080] The materials of the outer support 1 and the inner support 2 in the present invention are not particularly limited, and can be selected from common or general materials in the prior art, such as nitinol, titanium alloy, cobalt-chromium alloy, MP35n, 316 stainless steel, L605, Phynox / Elgiloy, platinum-chromium, or other biocompatible metals known to those skilled in the art or solid metal tubes cut by laser. Preferably, they are selected from shape memory alloys. For example, they can be selected from other elastically or plastically deformable materials, such as balloon expandable, or they can be shape memory alloys that respond to temperature changes to transform between a contracted delivery state and an expanded deployment state. Optionally, the stent can also be constructed of braided wire or other suitable materials.

[0081] The detachable connection or non-connection between the outer stent 1 and the inner stent 2 allows the outer stent 1 to be implanted in the body first, stably anchored in the atrioventricular space, and then the inner stent 2 is released; the inner stent 2 relies on its own grid structure, or self-expands, or expands in a ball shape, and is fixed in the middle of the outer stent. This detachable design of the inner and outer stents reduces the radial size of the delivery sheath in the delivery system, and can reduce the size of the first delivery system with a size of more than 35Fr to 28Fr; the size of the second delivery system or the third delivery system with a size of more than 35Fr can be reduced to 24Fr, which can solve the delivery problem caused by the oversized size of the double-layer stent delivery system in the prior art, and improve the safety of implantation and the universality of size.

[0082] like Figures 4-1 to 4-4 As shown, the present invention also provides a delivery system for an artificial heart valve, the delivery system comprising a delivery sheath 31, a guidewire cavity 32 sleeved in the delivery sheath 31, and a stent catheter 33, wherein the stent catheter 33 is configured to be suitable for connection with the artificial heart valve.

[0083] In such Figure 4-1 In the delivery system (first delivery system) shown, the stent catheter 33 includes an outer stent catheter 331 and an inner stent catheter 332, which are arranged in a front-to-back order in the delivery sheath 31, and the outer stent catheter 331 and the inner stent catheter 332 are both tubular. In this embodiment, the material of the inner stent frame 21 is selected from nickel-titanium alloy. The inner stent frame 21 can be self-expanding.

[0084] The cross-sectional area of ​​the inner support conduit 332 is larger than that of the outer support conduit 331. The outer support conduit 331 is inserted into the inner support conduit 332. The inner support conduit 332 is uniform in thickness. One end of the inner support conduit 332 is used to connect with the inner support 2. One end of the outer support conduit 331 is provided with a wide portion 33a. The wide portion 33a is used to connect with the outer support 1.

[0085] like Figure 5-1 As shown, the steps of implanting an artificial heart valve using such a delivery system are as follows: first, the inner and outer stents are respectively loaded on the inner stent catheter 332 and the outer stent catheter 331 and then implanted. During the implantation process, when the outer stent 1 is released, the delivery sheath 31 is retracted; after the outer stent 1 is released, the guidewire cavity 32 is retracted until it is close to the inner stent 2; the delivery system is adjusted so that the inner stent 2 is coaxially arranged with the outer stent 1 (the delivery system can be used to assist in coaxiality); the delivery sheath 31 continues to retract to release the inner stent 2; after the release is completed, the delivery sheath 31 is retracted and the delivery system is withdrawn.

[0086] In such Figure 4-2 and Figure 4-3 In the delivery system (second delivery system) shown, the delivery system further includes a bending control sheath 34 sleeved outside the delivery sheath tube 31, the stent catheter 33 is tubular, and a wide portion 33a is provided at one end of the stent catheter 33. The wide portion 33a is used to connect with the outer stent 1 or the inner stent 2.

[0087] In this embodiment, the material of the inner stent frame 21 is selected from nickel-titanium alloy. The inner stent frame 21 can be self-expanding.

[0088] like Figure 5-2 As shown, the steps of implanting an artificial heart valve using this delivery system are as follows: first, load the inner and outer stents into two identical delivery systems respectively. When implanting, implant the outer stent 1 first. The delivery system passes through the bending control sheath 34, and releases the outer stent 1 between the atrium and the chamber by withdrawing the delivery sheath 31. Then withdraw the delivery system. Next, pass the delivery system loaded with the inner stent 2 through the bending control sheath 34, and release the inner stent 2 into the cylindrical space of the outer stent 1 between the atrium and the chamber by withdrawing the delivery sheath 31.

[0089] In such Figure 4-4 In the delivery system (third delivery system) shown, the delivery system further includes a bending control sheath 34 sleeved outside the delivery sheath tube 31 , and the stent catheter 33 is in the shape of a balloon. The stent catheter 33 is used to be placed in the inner stent 2 .

[0090] In the delivery system of this embodiment, the material of the inner stent frame 21 is selected from cobalt-chromium alloy. The inner stent frame 21 can be expanded by balloon.

[0091] like Figure 5-3 As shown in the figure, the steps of implanting an artificial heart valve using this delivery system are as follows: first, load the outer stent 1 into the Figure 4-2 In the delivery system shown in FIG. 1 , the inner stent 2 is loaded into the Figure 4-4 In the delivery system shown in the figure, when implanting, the outer stent 1 is implanted first. Then, the delivery system equipped with the inner stent 2 is passed through the bending control sheath 34, and the delivery sheath 31 is first withdrawn between the atrioventricular space. Then, physiological saline is filled into the stent catheter 33, thereby expanding the inner stent 2 and fixing the inner stent 2 at the center position of the inner wall 112a of the outer stent 1.

[0092] The present invention also provides a heart valve replacement system, which includes the artificial heart valve and the delivery system.

[0093] In summary, the present invention effectively overcomes various shortcomings of the prior art and has high industrial utilization value.

[0094] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. An artificial heart valve, characterized in that: The artificial heart valve comprises an outer support (1) and an inner support (2), wherein the outer support (1) and the inner support (2) are detachably connected, or when the artificial heart valve is in use, the inner support (2) is located inside the outer support (1), the outer support (1) comprises an outer support frame (11) and a disposable valve leaf (12) arranged on the outer support frame (11), the outer support (1) further comprises an anchor (13), wherein the anchor (13) is arranged on the outer support frame (11); the surface of the anchor (13) is uneven; the disposable valve leaf (12) is arranged below the anchor (13); the outer support frame (11) comprises a flange portion (111), a main body portion (112) and a gripping ear portion (113) which are connected in sequence; the flange portion (111) comprises a first flange segment (111a), a second flange segment (111b) and a third flange segment (111c) which are connected in sequence, and when the outer support frame (11) is in use, the outer support frame (11) is detachably connected to the inner support frame (11); ... When the support frame (11) is placed vertically, the angle α between the second flange section (111b) and the horizontal direction is -10° to 55°; the main body (112) includes an inner wall (112a) and an outer wall (112b), the inner wall (112a) and the outer wall (112b) are connected end to end to form a closed structure, and the anchor (13) is a protrusion integrally formed with the inner wall (112a), or is an independent component fixedly connected to the inner wall (112a). a); the grabbing ear portion (113) comprises a first grabbing ear segment (113a), a second grabbing ear segment (113b) and a third grabbing ear segment (113c) which are connected in sequence; when the outer stent frame (11) is placed vertically, the degree of the angle β between the third grabbing ear segment (113c) and the vertical direction is -15° to 15°; the inner stent (2) comprises an inner stent frame (21) and an artificial valve leaflet (22) placed in the inner stent frame (21).

2. The artificial heart valve according to claim 1, characterized in that: The disposable leaflet (12) is arranged on the inner wall (112a).

3. The artificial heart valve according to claim 1, characterized in that: The outer bracket (1) further comprises an outer bracket skirt, wherein the outer bracket skirt is at least arranged on the surface of the flange portion (111) and the main body portion (112).

4. The artificial heart valve according to claim 1, characterized in that: The anchor (13) is arranged on the inner wall (112a).

5. The artificial heart valve according to claim 1, characterized in that: The inner support frame (21) is divided into an inflow section (211) and an outflow section (212), and the inner support (2) further comprises an inner support skirt (23), and the inner support skirt (23) is arranged on the inner surface of the inner support frame (21).

6. The artificial heart valve according to claim 5, characterized in that: The artificial valve leaflet (22) is connected to the inner support skirt (23).

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