A valve fixation device and method of manufacturing the same, a prosthetic heart valve system

Abstract

The present application relates to a kind of valve fixation device and its manufacturing method, artificial heart valve system, the valve fixation device, for the fixed effect of artificial heart valve outside organism blood vessel, it is C-shaped ring body with 5-30 ° opening, main body uses flexible biocompatibility material, multiple magnets are embedded in the material inside, and be completely wrapped by the material;The inner diameter a of C-shaped ring body is greater than the outer diameter b of the part matched with artificial heart valve, and the difference between inner diameter a and outer diameter b is (4-12]mm;Valve fixation device provides radial attractive force to artificial heart valve by multiple magnets, to fix artificial heart valve in its installed position in blood vessel.The present application is applicable to aortic valve, pulmonary valve replacement surgery such as valve replacement surgery, does not rely on the implementation of the existence of calcification at valve, and simple and reliable operation.

Description

Technical Field

[0001] This invention relates to the field of medical devices, specifically to a valve fixation device and its manufacturing method, and an artificial heart valve system. Background Technology

[0002] Aortic valve stenosis can easily lead to poor blood flow, causing pain and even endangering life. Currently, one of the main treatments for aortic valve stenosis is transcatheter implantation of an artificial heart valve, which is placed at the stenosis site to replace the diseased native valve and perform its function. However, this treatment method is currently only feasible if there is pathological thickening (i.e., calcification) of the aortic valve.

[0003] When artificial heart valves are used to replace native valves in other valves such as the pulmonary valve, there are also technical problems such as difficulty in fixing the artificial heart valve and complexity in operation. Summary of the Invention

[0004] Based on the above situation, the main objective of this invention is to provide a valve fixation device and its manufacturing method, as well as an artificial heart valve system, which is suitable for valve replacement surgery of aortic valve, pulmonary valve, etc., does not depend on the presence of calcification at the valve site for implementation, and is simple and reliable to operate.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows: In a first aspect, the present invention provides a valve fixation device for fixing an artificial heart valve outside the blood vessels of a living organism. The valve fixation device is a C-shaped ring with an opening, and the central angle corresponding to the opening is 5-30°. The main body of the valve fixation device is made of flexible biocompatible material. Multiple magnets are dispersed and embedded in the flexible biocompatible material along the circumference of the C-shaped ring and are completely wrapped by the flexible biocompatible material. The inner diameter a of the C-shaped ring of the valve fixation device is greater than the outer diameter b of the portion of the artificial heart valve that matches it, and the difference between the inner diameter a and the outer diameter b is (4-12) mm. The valve fixation device provides radial attraction to the artificial heart valve through the plurality of magnets to fix the artificial heart valve at its placement site within the blood vessel.

[0006] Preferably, the magnet is a spherical magnetic bead with a diameter of 3-10 mm and a distance of 5-12 mm between adjacent spherical magnetic beads in the circumferential direction of the C-shaped ring.

[0007] Preferably, the magnet is a cylindrical magnetic bead with a length of 3-10 mm and a diameter of 3-10 mm, and the distance between adjacent cylindrical magnetic beads in the circumferential direction of the C-shaped ring is 5-12 mm.

[0008] Preferably, the axis of the cylindrical magnetic beads is arranged along the radial direction of the valve fixation device, or parallel to the axial direction of the valve fixation device.

[0009] Preferably, the cross-section of the C-shaped annulus is circular, with a cross-sectional diameter of 6-12 mm.

[0010] Preferably, the difference between the inner diameter a and the outer diameter b is 5-8 mm.

[0011] Preferably, the main body of the valve fixation device includes flexible fibers, and multiple magnets are fixed into a single piece by weaving the flexible fibers.

[0012] In a second aspect, the present invention also provides a method for manufacturing a valve fixation device, as described above, whose body does not contain flexible fibers, comprising the following steps: S100, a molten flexible biocompatible material is injected into a lower mold, the lower mold having a first C-shaped groove with a semi-circular cross-section, the flexible biocompatible material filling the first C-shaped groove or reserving part of the space; S200, embedding multiple magnets at predetermined positions, each magnet being embedded to the extent of one-third to one-half of its volume; S300, scrape off the biocompatible material that overflowed from the first C-shaped groove due to the embedded magnet in step S200, and fasten the upper mold on the lower mold. The upper mold has a second C-shaped groove with a semi-circular cross section. After fastening, the second C-shaped groove is symmetrical in shape and corresponding in position to the first C-shaped groove. S400, inject molten flexible biocompatible material into the second C-shaped groove until the second C-shaped groove is filled; S500, the flexible biocompatible material in the upper mold and the lower mold is cooled to room temperature, and the mold is opened to obtain the valve fixation device.

[0013] Preferably, the flexible biocompatible material is silicone. The operating temperature for steps S100-S400 is 120~350°C.

[0014] Thirdly, the present invention also provides a method for manufacturing a valve fixation device with flexible fibers inside the body as described above, comprising the following steps: S100', multiple magnets are woven and fixed into a single piece at a preset interval using flexible fibers with a diameter of 0.02-0.1 mm. The flexible fibers surrounding each magnet can extend at least a first predetermined length to both sides of the magnet along a direction that coincides with the first central cross section of the magnet. S200', the integral part from step S100' is placed into the lower mold. The lower mold has a first C-shaped groove with a semi-circular cross-section. The width of the portion on both sides of the radial direction of the first C-shaped groove on the upper surface of the lower mold is less than the first predetermined length. The flexible fiber surrounding each magnet is extended outward from the portion on both sides of the radial direction of the first C-shaped groove. S300', the upper mold is fastened to the lower mold. The upper mold has a second C-shaped groove with a semi-circular cross-section. After fastening, the second C-shaped groove is symmetrical in shape and corresponding in position to the first C-shaped groove. In step S400', the flexible fibers extending outward from the radial sides of the first C-shaped groove in the flattening step S200' make the first central section of each magnet coincide with the snap-fit ​​plane between the lower mold and the upper mold, so that the multiple magnets can be located in the middle of the corresponding position of the cavity formed between the first C-shaped groove and the second C-shaped groove. S500', inject molten flexible biocompatible material into the cavity of step S400' until the cavity is filled, cool to room temperature, and open the mold to obtain a semi-finished product; S600', the flexible fibers exposed in the semi-finished product obtained in step S500' are removed, and the outer surface is polished until smooth to obtain the valve fixation device.

[0015] Preferably, in step S500', the flexible biocompatible material is silicone; the operating temperature when injecting the molten flexible biocompatible material is 120~350°C.

[0016] Preferably, step S500' involves injecting a predetermined ratio of polyisocyanate and polyol into the cavity of step S400' until the cavity is filled, generating the flexible biocompatible material through a crosslinking reaction, and then opening a mold to obtain a semi-finished product.

[0017] Fourthly, the present invention also provides an artificial heart valve system, including an artificial heart valve and a valve fixation device, wherein the valve fixation device is the valve fixation device described above or a valve fixation device made according to the method described above, and the artificial heart valve is used to be placed in a corresponding part of a blood vessel in an organism to replace the original heart valve. The artificial heart valve includes a valve stent, at least a portion of which is made of magnetic material.

[0018] Preferably, at least a portion of the distal end of the valve stent is made of magnetic material.

[0019] Preferably, the valve stent is made entirely of a magnetic material that does not exhibit magnetic properties, and at least a portion of the distal end is magnetized to make the distal end magnetic.

[0020] Preferably, the distal end of the valve stent is made of magnetic material, while the other parts of the valve stent are made of non-magnetic alloy material, and the distal end and the other parts are fixedly connected as a whole by welding.

[0021] The valve fixation device and its manufacturing method, as well as the artificial heart valve system provided by this invention, are designed as a C-shaped ring with a flexible biocompatible material as the main body. Multiple magnets are uniformly dispersed and embedded inside the flexible biocompatible material. The inner diameter of the valve fixation device is larger than the matching portion of the artificial heart valve by a sufficient margin, so that the inner diameter of the valve fixation device is slightly larger than the outer diameter of the blood vessel. Thus, the multiple magnets can provide radial attraction to the artificial heart valve to fix it at its placement site in the blood vessel. This invention is suitable for heart valve replacement surgery in the aorta, pulmonary artery, and other locations. It does not depend on the presence of calcification at the valve site for the procedure, does not cause damage to the blood vessel, and is easy to operate. The magnetic force is easy to adjust and control, and the fixation effect is good.

[0022] Other beneficial effects of the present invention will be explained in detail through the introduction of specific technical features and technical solutions in specific embodiments. Those skilled in the art should be able to understand the beneficial technical effects brought about by these technical features and technical solutions through the introduction of these technical features and technical solutions. Attached Figure Description

[0023] Preferred embodiments of the present invention will now be described with reference to the accompanying drawings. In the drawings: Figure 1 A schematic diagram of a preferred embodiment of the valve fixation device provided by the present invention in use inside the heart; Figure 2 This is a schematic diagram of a preferred embodiment of the valve fixation device provided by the present invention used in conjunction with an artificial heart valve (heart not shown); Figure 3 A three-dimensional structural schematic diagram of a preferred embodiment of the valve fixation device provided by the present invention; Figure 4 A cross-sectional structural schematic diagram of a preferred embodiment of the valve fixation device provided by the present invention; Figure 5 A top view of a preferred embodiment of the valve fixation device provided by the present invention; Figure 6 for Figure 5 A cross-sectional view along the AA direction; Figure 7 A flowchart illustrating a preferred embodiment of the method for manufacturing a valve fixation device whose body does not contain flexible fibers, provided by the present invention. Figure 8 A cross-sectional structural diagram of a preferred embodiment of a manufacturing method for the valve fixation device provided by the present invention, after the upper mold and the lower mold are fastened together; Figure 9 A flowchart illustrating a preferred embodiment of the method for manufacturing a valve fixation device comprising flexible fibers within a body, provided by the present invention. Figure 10 A top view schematic diagram of a preferred embodiment of another manufacturing method of the valve fixation device provided by the present invention, in which the upper mold and the lower mold are fastened together and the flexible fiber extends out of the lower mold. Figure 11 This is a cross-sectional schematic diagram of a preferred embodiment of the valve fixation device provided by the present invention, in which the upper mold and the lower mold are fastened together and the flexible fiber extends out of the lower mold. Detailed Implementation

[0024] The present invention is described below based on embodiments, but the present invention is not limited to these embodiments. In the following detailed description of the present invention, some specific details are described in detail, but well-known methods, processes, procedures, and elements are not described in detail in order to avoid obscuring the essence of the present invention.

[0025] Furthermore, those skilled in the art should understand that the accompanying drawings provided herein are for illustrative purposes only and are not necessarily drawn to scale.

[0026] Unless the context explicitly requires it, the words "comprising," "including," and similar terms throughout the specification and claims should be interpreted as encompassing rather than being exclusive or exhaustive; that is, meaning "including but not limited to."

[0027] In the description of this invention, it should be understood that the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance. Furthermore, in the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0028] Firstly, see Appendix Figures 1-6 The present invention provides a valve fixation device 10 for fixing an artificial heart valve 20 outside the blood vessels of a living organism. The valve fixation device 10 is a C-shaped annular body with an opening 13, and the central angle corresponding to the opening is 5-30°. The main body 11 of the valve fixation device 10 is made of flexible biocompatible material, and multiple magnets 12 are dispersed and embedded in the flexible biocompatible material along the circumference of the C-shaped ring and are completely wrapped by the flexible biocompatible material. The inner diameter a of the C-shaped annulus of the valve fixation device 10 is greater than the outer diameter b of the portion of the artificial heart valve that matches it, and the difference between the inner diameter a and the outer diameter b is (4-12) mm. The valve fixation device 10 provides radial attraction to the artificial heart valve 20 through the plurality of magnets 12 to fix the artificial heart valve 20 at its placement site within the blood vessel.

[0029] Specifically, taking the application of this invention to aortic valve surgery in a living organism as an example, in this surgery, an artificial heart valve 20 is placed at the valve position inside the aorta, replacing the native aortic valve to perform the corresponding function. Since artificial heart valves are typically designed to be the same size as or slightly larger than the native valve, after the artificial heart valve is delivered and released from the delivery device, the native structure of the blood vessel at the valve position can contact the artificial heart valve and provide initial support. The valve fixation device provided by this invention surrounds the blood vessel at the position corresponding to the artificial heart valve. It is well fixed to the outside of the corresponding blood vessel by means of the gap between the surrounded blood vessel and other blood vessels, and / or by surrounding tissues, fat, etc. For example, in aortic valve replacement surgery, the valve fixation device can be held in place radially by the pulmonary artery, superior vena cava, etc., outside the aorta, and supported vertically by the heart's fat, tissues, etc. The valve fixation device 10 provides a radial magnetic attraction to the artificial heart valve 20 within the blood vessel through multiple magnets 12. The artificial heart valve 20 is attracted by this magnetic force through its own material selection (such as selecting its stent as a magnetic material), so that the artificial heart valve 20 no longer displaces under the action of the radial magnetic attraction (because the valve fixation device is already fixed in position, the valve fixation device will not displace significantly, so the artificial heart valve attracted by the valve fixation device will not sway up and down along the blood vessel), and is reliably fixed in its placement position within the blood vessel.

[0030] A magnet is an object with magnetic properties that provides magnetic attraction. Under the premise of safety and non-toxicity, the materials used for the plurality of magnets 12 in this invention are not limited. For example, they can be selected from AlNiCo permanent magnet alloys, IronChromiumCo permanent magnet alloys, permanent magnet ferrites, rare earth permanent magnet materials, and composite permanent magnet materials, or other soft magnetic materials. The plurality of magnets 12 are preferably arranged uniformly and symmetrically in the valve fixation device 10 to ensure that the valve fixation device 10 can apply force evenly to the artificial heart valve 20, avoiding deformation of the artificial heart valve 20 due to uneven force.

[0031] The main body 11 of the valve fixation device 10 is made of a flexible biocompatible material, such as silicone, polyurethane, or other thermoplastic elastomer (TPE) materials. Multiple magnets 12 are completely encased in the flexible biocompatible material and do not protrude from the main body 11, making the valve fixation device 10 a C-shaped annular body with a regular cross-section (see Appendix). Figures 5-6 Here, the cross-section refers to the section perpendicular to the C-shaped axis of the C-shaped annulus, for example... Figure 6 The cross section pointed to by the middle arrow.

[0032] The overall size of the valve fixation device 10 can be selected according to actual needs. In one example, the inner diameter of the valve fixation device 10 is 18-35 mm, and the outer diameter is 24-45 mm.

[0033] Those skilled in the art will understand that, considering that the valve fixation device 10 is a component implanted in the human body, for safety and comfort reasons, the outer surface of the valve fixation device 10 should be as smooth as possible.

[0034] In one example, the valve fixation device is delivered in a manner similar to transapical delivery to the target site. Specifically, a small incision is made between the ribs of the organism, and the delivery system containing the valve fixation device is then delivered through the incision into the organism until the site of surgery.

[0035] By designing the valve fixation device 10 as a C-shaped annulus with an opening 13 having a central angle of 5-30°, it is easy to fit the valve fixation device onto the corresponding blood vessel after it has been delivered and positioned, by opening the opening 13. In one example, the valve fixation device is fitted and installed in such a way that, since the main body 11 of the valve fixation device 10 is made of elastic silicone, after the opening 13 is opened and fitted onto the blood vessel using external force, the opening 13 of the valve fixation device 10 can actively return to its unforced state and is not easily dislodged from the blood vessel. The purpose of the opening 13 is mainly to facilitate the delivery and fitting of the valve fixation device. After the valve fixation device is fitted and installed at the corresponding height position on the blood vessel, the orientation of the opening 13 is not restricted within the circumferential range at that height. The two ends of the opening 13 can be flat or two relatively convex hemispheres, the radius of which is equal to the cross-sectional radius of the main body of the C-shaped annulus (i.e., the non-end portion). Since the valve fixation device 10 fixes the artificial heart valve 20 by providing magnetic force, by adjusting the number, size and material of the magnets 12, the valve fixation device 10 can provide sufficient attraction to the artificial heart valve 20. Not only do the artificial heart valve 20 and the valve fixation device 10 not need to be in direct contact with each other, but the diameter (inner diameter) of the valve fixation device 10 can also be slightly larger than the outer diameter of the matching blood vessel. It is not necessary to use the valve fixation device 10 to clamp the blood vessel to hold the artificial heart valve 20 located inside the blood vessel, thus avoiding damage to the blood vessel. Specifically, considering the need for miniaturization of the valve fixation device to facilitate minimally invasive surgery, and given that the thinnest wall of the blood vessel it matches is typically 2 mm thick, the inner diameter *a* of the C-shaped annulus of the valve fixation device is made larger than the outer diameter *b* of the portion of the artificial heart valve that matches it. The difference between the inner diameter *a* and the outer diameter *b* is (4-12] mm, i.e., greater than 4 mm and not exceeding 12 mm. This ensures that the inner diameter *a* of the C-shaped annulus is greater than the portion of the artificial heart valve that is attracted by the valve fixation device (i.e., the portion of the artificial heart valve that matches the C-shaped annulus). Figure 2 For example, the dashed box indicated by the arrow in the left image shows the part that matches the C-shaped annulus, and the right image is a specific cutaway diagram of this part. The outer diameter *b* has a certain margin, which is greater than the thickness of the blood vessel at that location, thus allowing the inner diameter *a* to be larger than the outer diameter of the matching blood vessel. For ease of reference, the inner diameter *a* is... Figure 5 As already marked, the outer diameter b is in Figure 2 The right-hand image is already labeled.

[0036] The valve fixation device 10 provided by this invention is a C-shaped annular body. The main body 11 is made of flexible biocompatible material, and multiple magnets 12 are dispersedly embedded inside the flexible biocompatible material. The inner diameter of the valve fixation device 10 is larger than the portion of the artificial heart valve that it matches by a sufficient margin, so that the inner diameter of the valve fixation device is slightly larger than the outer diameter of the matching blood vessel. This allows the multiple magnets 12 to provide radial attraction to the artificial heart valve 20, thereby fixing the artificial heart valve 20 to its placement site within the blood vessel. It is suitable for heart valve replacement surgery in the aorta, pulmonary artery, and other locations. Because it uses a specialized valve fixation device 10... The artificial heart valve 20 is fixed in place by the 0, thus it does not rely on the presence of calcification at the valve site to provide sufficient support strength for fixation. Since the inner diameter of the valve fixation device 10 is slightly larger than the outer diameter of the blood vessel at the application site, it will not cause damage to the blood vessel. Since the magnetic force can be adjusted by the number, size, and material of the magnets 12, the configuration of the magnets 12 can be easily adjusted for different individual patients to ensure that the valve fixation device 10 can provide sufficient magnetic force and achieve good and reliable fixation. Furthermore, the valve fixation device 10 of the present invention has a simple structure, so it is relatively easy to operate and convenient to use in complex surgeries such as heart valve replacement.

[0037] Preferably, the magnet 12 is a spherical magnetic bead with a diameter of 3-10 mm and a distance of 5-12 mm between adjacent spherical magnetic beads in the circumferential direction of the C-shaped annulus.

[0038] Choosing spherical magnetic beads as magnets is convenient for manufacturing. Due to the central symmetry of the sphere, it is also easy to position each spherical magnetic bead in the middle of the valve fixation device 10 during the manufacturing process (see the subsequent introduction of the manufacturing method). This ensures that none of the magnets protrude from the surface of the valve fixation device, which helps to keep the surface of the magnetic fixation device smooth.

[0039] By selecting the parameters for the spherical magnetic beads as described above, the spherical magnetic beads can be distributed in the valve fixation device 10 at a preferred density, which facilitates providing appropriate magnetic attraction and prevents the magnetic beads from being too small to be easily manipulated. The distance between adjacent spherical magnetic beads is calculated based on the shortest distance between the outer walls of two spherical magnetic beads.

[0040] Preferably, the magnet 12 is a cylindrical magnetic bead with a length of 3-10 mm and a diameter of 3-10 mm, and the distance between adjacent cylindrical magnetic beads in the circumferential direction of the C-shaped annulus is 5-12 mm. Preferably, the axes of the cylindrical magnetic beads are arranged along the radial direction of the valve fixation device, or parallel to the axial direction of the valve fixation device.

[0041] When cylindrical magnetic beads are used, it is relatively easy to arrange the polarity of each magnetic bead, for example, to avoid repulsion between adjacent magnets due to polarity.

[0042] By selecting the parameters for the cylindrical magnetic beads as described above, the cylindrical magnetic beads can be distributed in the valve fixation device 10 at a preferred density, which facilitates providing appropriate magnetic attraction and prevents the magnetic beads from being too small to be easily manipulated. The distance between adjacent cylindrical magnetic beads is calculated based on the shortest distance between the outer walls of two cylindrical magnetic beads.

[0043] Preferably, the cross-section of the C-shaped annulus is circular, with a cross-sectional diameter of 6-12 mm.

[0044] To improve the ease of transporting the valve fixation device 10 to the surgical site, the cross-sectional shape of the C-shaped annulus is preferably circular.

[0045] Taking into account the size of the internal cardiac environment, ease of delivery, and the performance requirements of the valve fixation device 10, the cross-sectional size of the C-shaped annulus was selected as 6-12 mm.

[0046] Preferably, the difference between the inner diameter a and the outer diameter b is 5-8 mm.

[0047] By making the difference between the inner diameter a and the outer diameter b 5-8 mm, that is, greater than or equal to 5 mm and not exceeding 8 mm, it is possible to ensure that the inner diameter a of the C-shaped ring is larger than the outer diameter b of the portion of the artificial heart valve that is attracted by the valve fixation device by a sufficient margin, while minimizing the valve fixation device 10 as much as possible. This further reduces the possibility of damage to blood vessels caused by the valve fixation device constricting the blood vessels.

[0048] Preferably, the main body of the valve fixation device 10 includes flexible fibers, and multiple magnets 12 are fixed into a single piece by weaving the flexible fibers.

[0049] Secondly, see the appendix. Figures 7-8 The present invention also provides a method for manufacturing a valve fixation device 10, as described above, whose body does not contain flexible fibers, comprising the following steps: S100, a molten flexible biocompatible material is injected into the lower mold 32, the lower mold 32 having a first C-shaped groove 32' with a semi-circular cross-section, the flexible biocompatible material filling or reserving part of the space in the first C-shaped groove 32'; S200, embedding a plurality of magnets 12 at predetermined positions, each magnet 12 being embedded to the extent of one-third to one-half of its volume; S300, scrape off the biocompatible material that overflowed from the first C-shaped groove 32' due to the embedding of the magnet 12 in step S200, and fasten the upper mold 31 onto the lower mold 32. The upper mold 31 has a second C-shaped groove 31' with a semi-circular cross section. After fastening, the second C-shaped groove 31' and the first C-shaped groove 32' are symmetrical in shape and corresponding in position. S400, inject molten flexible biocompatible material into the second C-shaped groove 31' until the second C-shaped groove 31' is filled; S500, the flexible biocompatible material in the upper mold 31 and the lower mold 32 is cooled to room temperature, and the mold is opened to obtain the valve fixation device 10.

[0050] In this manufacturing method, two molds, an upper mold 31 and a lower mold 32, are used. Each mold has a C-shaped groove with a semi-circular cross-section, namely the first C-shaped groove 31' and the second C-shaped groove 32'. After the upper mold 31 and the lower mold 32 are engaged, the first C-shaped groove 31' and the second C-shaped groove 32' are symmetrical in shape (obviously, their dimensions are the same for symmetry) and positioned opposite each other. The contour of the cavity formed between them matches the outer contour of the valve fixing device, and the valve fixing device is finally formed in the cavity. Both the upper mold 31 and the lower mold 32 can be C-shaped molds. Compared with other shapes such as rectangular molds with C-shaped grooves, designing the mold as C-shaped can effectively save mold manufacturing materials.

[0051] Specifically, before final molding, the flexible biocompatible material is in a molten state to facilitate the embedding of the plurality of magnets 12 and to facilitate its injection into the mold.

[0052] First, the lower mold 32 is positioned so that the opening of the first C-shaped groove 32' is facing upwards rather than downwards. An appropriate amount of molten biocompatible material is injected into the lower mold 32 to fill or reserve some space in the first C-shaped groove 32', facilitating the embedding of multiple magnets 12.

[0053] Based on the pre-designed distribution of magnets in the valve fixation device, corresponding magnets are embedded at the corresponding positions in the molten material in the lower mold. To ensure that any magnet 12 is encased in the flexible biocompatible material, the magnet 12 must not sink to the bottom of the first C-shaped groove but must be supported by the molten material. Therefore, the degree to which each magnet 12 is embedded in the lower mold is controlled to be one-third to one-half of its own volume. Because the cross-sectional dimension of the magnet 12 is necessarily smaller than the cross-sectional dimension of the valve fixation device, the portion of the magnet 12 embedded in the lower mold 32 will not sink to the bottom of the first C-shaped groove 32' if the degree of embedding in the lower mold 32 does not exceed one-half of its own volume. The degree to which the magnet 12 is embedded in the lower mold 32 can be adjusted by selecting appropriate melt density, magnet density, and the volume of melt injected into the lower mold during the design phase.

[0054] After each magnet 12 is embedded, the molten material that overflows from the first C-shaped groove 32' due to the embedding of the magnet 12 is scraped off. Those skilled in the art will understand that the scraping here mainly refers to scraping off the molten material that has overflowed from the first C-shaped groove 32' and reached the front surface of the lower mold 32, so as not to affect the fastening between the lower mold 32 and the upper mold 31, that is, to avoid gaps between the front surface of the lower mold 32 and the upper mold 31 after fastening due to the influence of the unscraped molten material.

[0055] After the scraping process is completed, the upper mold 31 and the lower mold 32 are fastened together, and the molten flexible biocompatible material is continued to be filled to completely fill the second C-shaped groove 31' of the upper mold 31, that is, to completely fill the cavity formed after the upper and lower molds are fastened together. The melt is then cooled to room temperature to solidify and form the shape. After the mold is opened, the valve fixing device 10 is obtained.

[0056] Preferably, the flexible biocompatible material is silicone; the operating temperature of steps S100-S400 is 120~350°C.

[0057] Silicone has good biocompatibility with the human body and also has good flexibility, making it suitable as the main material for the valve fixation device.

[0058] To ensure that the silicone is in a molten state during steps S100-S400, the temperature of steps S100-S400 is set to 120~350°C.

[0059] Thirdly, see appendix. Figures 9-11 The present invention also provides a method for manufacturing a valve fixation device having a flexible fiber internally as described above, comprising the following steps: S100', multiple magnets are woven and fixed into a single piece at a preset interval using flexible fibers 14 with a diameter of 0.02-0.1 mm. The flexible fibers 14 surrounding each magnet can extend at least a first predetermined length to both sides of the magnet 12 along the direction that coincides with the first central cross section of the magnet. S200', the integral part from step S100' is placed into the lower mold 32. The lower mold 32 has a first C-shaped groove 32' with a semi-circular cross section. On the upper surface of the lower mold 32, the width of the portion located on both radial sides of the first C-shaped groove 32' is less than the first predetermined length. The flexible fiber 14 surrounding each magnet 12 is extended outward from the portion located on both radial sides of the first C-shaped groove 32'. S300', the upper mold 31 is fastened to the lower mold 32. The upper mold 31 has a second C-shaped groove 31' with a semi-circular cross section. After fastening, the second C-shaped groove 31' is symmetrical in shape and corresponding in position to the first C-shaped groove 32'. In step S400', the flexible fibers 14 extending outward from both sides of the first C-shaped groove 32' in the flattening step S200' are such that the first central section of each magnet 12 coincides with the fastening plane between the lower mold 32 and the upper mold 31, thereby enabling the plurality of magnets 12 to be located in the middle of the corresponding position of the cavity formed between the first C-shaped groove 32' and the second C-shaped groove 31'; S500', inject molten flexible biocompatible material into the cavity of step S400' until the cavity is filled, cool to room temperature, and open the mold to obtain a semi-finished product; S600', the flexible fibers exposed in the semi-finished product obtained in step S500' are removed, and the outer surface is polished until smooth to obtain the valve fixing device 10.

[0060] In this manufacturing method, two molds, an upper mold 31 and a lower mold 32, are also used. The lower mold 32 has a first C-shaped groove 32', and the upper mold 31 has a second C-shaped groove 31'. After the upper mold 31 and the lower mold 32 are engaged, the first C-shaped groove 31' and the second C-shaped groove 32' are symmetrical in shape (obviously, their dimensions are the same for symmetry) and positioned opposite each other. The contour of the cavity formed between them matches the outer contour of the valve fixing device 10, and the valve fixing device 10 is finally formed in this cavity. Both the upper mold 31 and the lower mold 32 can also be C-shaped molds (see Appendix). Figure 7 ).

[0061] The specific method for making this product is described below: First, according to the pre-designed distribution of magnets 12 in the valve fixation device 10, the multiple magnets 12 are fixed into a single piece by weaving the flexible fibers 14 at preset intervals. The flexible fibers 14 surrounding each magnet 12 are extended at least a first predetermined length to both sides of the magnet along the direction coinciding with the first central cross section of the magnet. This allows each magnet 12 to be positioned in the middle of the cavity by pulling on these extended flexible fibers 14, i.e., without direct contact with the cavity wall. This ensures that after the biocompatible material in a molten state is injected, the melt can completely encapsulate each magnet 12. At this time, the first central section is a section passing through a certain central plane of the magnet. When selecting the first central section, as long as the section coincides with the snap-fit ​​plane of the upper mold 31 and the lower mold 32, the magnet can be completely located in the middle of the cavity, that is, it does not contact any cavity wall, so that the melt can completely encapsulate the magnetic material. (Obviously, when the magnet is a spherical magnetic bead, since the diameter of the spherical magnetic bead is smaller than the diameter of the cavity, and the spherical magnetic bead is a centrally symmetric component, the first central section can be conveniently and directly selected as any section passing through the center of the sphere.)

[0062] After the integral part is woven, it is placed into the lower mold 32. The surface of the lower mold 32 with the first C-shaped groove 32' is the upper surface. The width of the portion on both sides of the first C-shaped groove 32' on the upper surface is less than the first predetermined length. In this way, the flexible fiber 14 surrounding each magnet extends outward until it extends outward from the portion on both sides of the first C-shaped groove 32' on the upper surface.

[0063] Then, the upper mold 31 is fastened to the corresponding part of the lower mold 32. The flexible fibers 14 that extend to both sides of the first C-shaped groove 32' are then flattened, so that the first central section of each magnet 12 coincides with the fastening plane between the lower mold 32 and the upper mold 31. This allows the multiple magnets 12 to be located in the middle of the corresponding position of the cavity formed between the first C-shaped groove 31' and the second C-shaped groove 32', i.e., without contacting any cavity wall. Then, molten flexible biocompatible material is injected into the cavity until it is filled. The cavity is cooled to room temperature to solidify and form a shape. The mold is then opened to obtain the semi-finished product of the valve fixation device.

[0064] Finally, the flexible fibers that extend beyond the semi-finished product are removed, for example, by cutting or shaving, and the outer surface is polished until smooth to obtain the finished valve fixation device 10.

[0065] Preferably, in step S500', the flexible biocompatible material is silicone; the operating temperature when injecting the molten flexible biocompatible material is 120~350°C.

[0066] Silicone has good biocompatibility with the human body and also has good flexibility, making it suitable as the main material for the valve fixation device.

[0067] To ensure that the silicone remains in a molten state, the operating temperature for injecting the flexible biocompatible material in step S500' is set to 120~350°C.

[0068] Preferably, step S500' involves injecting a predetermined ratio of polyisocyanate and polyol into the cavity of step S400' until the cavity is filled, generating the flexible biocompatible material through a crosslinking reaction, and then opening a mold to obtain a semi-finished product.

[0069] Specifically, instead of injecting molten biocompatible material into the cavity and then cooling it to room temperature to solidify it, the body of the valve fixation device can be formed by injecting a predetermined proportion of reaction raw materials into the cavity sequentially, using the cavity as a reaction chamber, and generating solid biocompatible material through a cross-linking reaction within the cavity.

[0070] In one example, the raw materials may be selected from polycyanates and polyols, wherein the polycyanate may be further selected from diphenylmethane diisocyanate monomers, toluene diisocyanate, or derivatives thereof; and the polyol may be further selected from polyester polyols or polyether polyols. Polycyanates are highly reactive and can react with polyols at room temperature without a catalyst to produce solid biocompatible materials.

[0071] Fourthly, the present invention also provides an artificial heart valve system, including an artificial heart valve 20 and a valve fixation device 10, wherein the valve fixation device is a valve fixation device as described above or a valve fixation device made according to the above method, and the artificial heart valve 20 is used to be placed in a corresponding part of a blood vessel in an organism to replace the original heart valve. The artificial heart valve 20 includes a valve stent 21, at least a portion of which is made of magnetic material.

[0072] Specifically, the artificial heart valve 20 typically includes a tubular or similarly tubular valve support 21 and an artificial leaflet, with the artificial leaflet fixed to the proximal end of the artificial heart valve 20. After the artificial heart valve replaces the original heart valve, the artificial leaflet is located inside the valve support 21 and functions in place of the original leaflet.

[0073] The valve stent 21 is made of a magnetic material. Generally speaking, magnetic materials can possess magnetic properties, providing magnetic attraction and being attracted by other magnets; or they can lack magnetic properties, such as iron, aluminum, nickel-chromium alloys, stainless steel, etc., which, while not providing magnetic attraction themselves, can be attracted by magnets with magnetic properties. Within the aforementioned range of generally understood magnetic materials, considering the requirements for safety, strength, and lightweight for biological use, a suitable material is selected to manufacture the valve stent.

[0074] By making at least a portion of the valve stent 21 a magnetic material, the valve stent 21 can be attracted by a plurality of magnets in the valve fixation device, thereby being fixed in the corresponding part of the blood vessel in the organism.

[0075] By making one part of the valve stent 21 magnetic and the other part non-magnetic, it is easy to make a specific part of the valve stent (i.e. the part with magnetic material) be attracted by the valve fixing device. By positioning the valve fixing device, the valve stent can be positioned so that the position of the valve stent is not too high or too low.

[0076] Preferably, at least a portion of the distal end of the valve stent 21 is made of magnetic material.

[0077] Considering that the proximal end of the valve stent 21 is usually more complex in structure due to usage requirements, and the original structure inside the blood vessel at the proximal end is also more complex, at least a portion of the distal end of the valve stent is designed to be made of magnetic material, so that the valve fixation device 10 can attract the distal end of the valve stent 21, which makes it easier to perform the actual operation in the heart valve replacement surgery.

[0078] Preferably, the valve stent 21 is made entirely of a magnetic material that does not exhibit magnetic properties, and at least a portion of the distal end is magnetized to make the distal end magnetic.

[0079] In one example, a nickel-chromium alloy is used to fabricate the entire valve stent 21. While nickel-chromium alloy is not magnetic, it can be attracted by magnetic force. By magnetizing at least a portion of the distal end of this nickel-chromium alloy valve stent, that portion becomes magnetic. Compared to other non-magnetic portions of the stent, this magnetic portion is more easily attracted by magnetic force; that is, it is preferentially attracted. Therefore, in this case, it is this magnetized portion of the valve stent 21 that is attracted by the multiple magnets in the valve fixation device 10.

[0080] "Magnetizing at least a portion of the distal end" does not require magnetization to begin from the end of the distal end, as long as the magnetized portion is relatively closer to the distal end rather than the proximal end.

[0081] Preferably, the distal end of the valve stent 21 is made of magnetic material, while the other parts of the valve stent 21 are made of non-magnetic alloy material, and the distal end and the other parts are fixedly connected as a whole by welding.

[0082] Non-magnetic materials refer to materials that are not attracted by magnetic forces. By making the distal end of the valve stent magnetic and the other parts non-magnetic, the valve fixation device can attract the distal end of the valve stent, thereby positioning and fixing the valve stent in the corresponding part of the blood vessel in the organism.

[0083] Those skilled in the art will understand that, without conflict, the above-mentioned preferred solutions can be freely combined and superimposed.

[0084] It should be understood that the above embodiments are merely exemplary and not restrictive. Various obvious or equivalent modifications or substitutions that can be made by those skilled in the art regarding the above details without departing from the basic principles of the present invention will be included within the scope of the claims of the present invention.

Claims

1. A valve fixation device for fixing an artificial heart valve outside the blood vessels of a living organism, characterized in that: The valve fixation device is a C-shaped ring with an opening, and the central angle corresponding to the opening is 5-30°. The main body of the valve fixation device is made of flexible biocompatible material. Multiple magnets are dispersed and embedded in the flexible biocompatible material along the circumference of the C-shaped ring and are completely wrapped by the flexible biocompatible material. The inner diameter a of the C-shaped ring of the valve fixation device is greater than the outer diameter b of the portion of the artificial heart valve that matches it, and the difference between the inner diameter a and the outer diameter b is (4-12) mm. The valve fixation device provides radial attraction to the artificial heart valve through the plurality of magnets to fix the artificial heart valve at its placement site within the blood vessel.

2. The valve fixation device according to claim 1, characterized in that, The magnet is a spherical magnetic bead with a diameter of 3-10 mm and a distance of 5-12 mm between adjacent spherical magnetic beads in the circumferential direction of the C-shaped ring.

3. The valve fixation device according to claim 1, characterized in that, The magnet is a cylindrical magnetic bead with a length of 3-10 mm and a diameter of 3-10 mm. The distance between adjacent cylindrical magnetic beads in the circumferential direction of the C-shaped ring is 5-12 mm.

4. The valve fixation device according to claim 3, characterized in that, The axis of the cylindrical magnetic beads is arranged along the radial direction of the valve fixation device, or parallel to the axial direction of the valve fixation device.

5. The valve fixation device according to claim 1, characterized in that, The cross-section of the C-shaped annulus is circular, with a diameter of 6-12 mm.

6. The valve fixation device according to any one of claims 1-5, characterized in that, The difference between the inner diameter a and the outer diameter b is 5-8 mm.

7. The valve fixation device according to any one of claims 1-5, characterized in that, The main body of the valve fixation device includes flexible fibers, and multiple magnets are fixed into a single unit by weaving the flexible fibers.

8. A method for manufacturing the valve fixation device as described in any one of claims 1-6, characterized in that, Includes the following steps: S100, a molten flexible biocompatible material is injected into a lower mold, the lower mold having a first C-shaped groove with a semi-circular cross-section, the flexible biocompatible material filling the first C-shaped groove or reserving part of the space; S200, embedding multiple magnets at predetermined positions, each magnet being embedded to the extent of one-third to one-half of its volume; S300, scrape off the biocompatible material that overflowed from the first C-shaped groove due to the embedded magnet in step S200, and fasten the upper mold on the lower mold. The upper mold has a second C-shaped groove with a semi-circular cross section. After fastening, the second C-shaped groove is symmetrical in shape and corresponding in position to the first C-shaped groove. S400, the molten flexible biocompatible material is injected into the second C-shaped groove until the second C-shaped groove is filled; S500, the flexible biocompatible material in the upper mold and the lower mold is cooled to room temperature, and the mold is opened to obtain the valve fixation device.

9. The method as described in claim 8, characterized in that, The flexible biocompatible material is silicone. The operating temperature for steps S100-S400 is 120~350°C.

10. A method for manufacturing the valve fixation device as described in claim 7, characterized in that, Includes the following steps: S100', multiple magnets are woven and fixed into a single piece at a preset interval using flexible fibers with a diameter of 0.02-0.1 mm. The flexible fibers surrounding each magnet can extend at least a first predetermined length to both sides of the magnet along a direction that coincides with the first central cross section of the magnet. S200', the integral part from step S100' is placed into the lower mold. The lower mold has a first C-shaped groove with a semi-circular cross-section. The width of the portion on both sides of the radial direction of the first C-shaped groove on the upper surface of the lower mold is less than the first predetermined length. The flexible fiber surrounding each magnet is extended outward from the portion on both sides of the radial direction of the first C-shaped groove. S300', the upper mold is fastened to the lower mold. The upper mold has a second C-shaped groove with a semi-circular cross-section. After fastening, the second C-shaped groove is symmetrical in shape and corresponding in position to the first C-shaped groove. In step S400', the flexible fibers extending outward from the radial sides of the first C-shaped groove in the flattening step S200' make the first central section of each magnet coincide with the snap-fit ​​plane between the lower mold and the upper mold, so that the multiple magnets can be located in the middle of the corresponding position of the cavity formed between the first C-shaped groove and the second C-shaped groove. S500', inject molten flexible biocompatible material into the cavity of step S400' until the cavity is filled, cool to room temperature, and open the mold to obtain a semi-finished product; S600', the flexible fibers exposed in the semi-finished product obtained in step S500' are removed, and the outer surface is polished until smooth to obtain the valve fixation device.

11. The method of the valve fixation device as described in claim 10, characterized in that, In step S500', the flexible biocompatible material is silicone; the operating temperature when injecting the molten flexible biocompatible material is 120~350°C.

12. The method of the valve fixation device as described in claim 10, characterized in that, Step S500' involves injecting a predetermined ratio of polyisocyanate and polyol into the cavity of step S400' until the cavity is filled, generating the flexible biocompatible material through a cross-linking reaction, and then opening a mold to obtain a semi-finished product.

13. An artificial heart valve system, characterized in that, The invention includes an artificial heart valve and a valve fixation device, wherein the valve fixation device is the valve fixation device according to any one of claims 1-7 or the valve fixation device made according to any one of claims 8-12, and the artificial heart valve is used to be placed in a corresponding part of a blood vessel in an organism to replace the original heart valve. The artificial heart valve includes a valve stent, at least a portion of which is made of magnetic material.

14. The system according to claim 13, characterized in that, At least a portion of the distal end of the valve stent is made of magnetic material.

15. The system according to claim 14, characterized in that, The valve stent is made entirely of a magnetic material that does not exhibit magnetic properties, but at least a portion of the distal end is magnetized to make the distal end magnetic.

16. The system according to claim 14, characterized in that, The distal end of the valve stent is made of magnetic material, while the other parts of the valve stent are made of non-magnetic alloy. The distal end and the other parts are fixedly connected as a whole by welding.

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