A heart valve replacement prosthesis and its internal stent

Abstract

The present invention discloses a heart valve replacement prosthesis and its inner support, belonging to the field of medical devices. The inner support adopts a cylindrical frame structure surrounded by three arched suture frames. The two adjacent arch column parts of the three arched suture frames are merged into a support rod. The lower parts of the three support rods are retracted to form the tail of the inner support for the tether to pass through and be fixed. The arched interior of the three arched suture frames is provided with an X-shaped connecting frame. The tops of the three arched suture frames are provided with suture limit holes. The angle of the retraction of the lower part of the support rod is 10-50°. The present invention greatly increases the space between the support rods by changing the 6 support rods of the existing suture frame into 3 support rods, and through the setting of the X-shaped connecting frame, it ensures sufficient rigidity of the inner support, forms a tail structure that will not squeeze or block the outflow duct, and can ensure the rigidity of the inner support, thereby truly solving the problem of outflow duct obstruction. It is also simple to produce and process, has reasonable stress distribution, strong fatigue resistance, and a long service life.

Description

Technical Field

[0001] The present invention relates to the field of medical devices, and in particular to a heart valve replacement prosthesis and an internal stent thereof. Background Art

[0002] Currently, the best treatment options for heart valve disease are surgical valve replacement or interventional repair or replacement. Transapical valve repair or replacement is gaining acceptance in the medical community because it combines the advantages of both surgery and interventional procedures.

[0003] Currently, well-known medical device manufacturers at home and abroad, such as Medtronic, Abbott, Edwards, MicroPort, Venus, and Pejia, have launched products for interventional valve replacement. Among them, Abbott's Tendyne product has attracted the most attention. It mainly adopts a D-type anatomical design with an inner and outer double-layer stent structure. The outer stent provides morphological support, and the inner stent maintains the valve shape. This requires the inner stent to have sufficient rigidity when designed, such as the attached Figure 1 and 2 As shown, the key feature of the Tendyne stent is its six struts, which offer sufficient rigidity. These six struts rapidly retract at the rear end, creating a very cramped and crowded structure. For patients with severe lesions or short outflow tracts, this structural design can obstruct the outflow tract, resulting in negative consequences. To address this issue, the Tendyne product expanded its stent specifications to cover a wider range of patients. However, this solution had a disastrous consequence: the number of Tendyne product specifications and models almost doubled to 23, increasing production and inventory costs while also making prosthesis selection more difficult for surgeons. Furthermore, due to the Tendyne stent's inherent structure, the six struts are prone to uneven distribution during production, compromising proper use. Furthermore, the congested rear end of the stent can easily cause stent fracture during molding.

[0004] As can be seen, the existing stents for heart valve replacement prostheses still suffer from inconveniences and drawbacks in their structure, methods, and use, and are in urgent need of further improvement. The industry is currently striving to develop a new heart valve replacement prosthesis and stent that can address the cramped and crowded conditions at the stent's rear end, while also ensuring sufficient rigidity to truly resolve the technical issue of outflow tract obstruction, while also offering ease of production and processing, reasonable stress distribution, strong fatigue resistance, and a long service life. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide an internal stent for a heart valve replacement prosthesis, which can not only solve the cramped and crowded state of the tail of the internal stent, but also ensure that it has sufficient rigidity, truly solving the technical problem of the outflow tract being blocked, and is easy to produce and process, has reasonable stress distribution, strong fatigue resistance, and a long service life, thereby overcoming the shortcomings of the existing internal stents for heart valve replacement prostheses.

[0006] In order to solve the above technical problems, the present invention provides an internal stent for a heart valve replacement prosthesis, which adopts a cylindrical frame structure surrounded by three arched suture frames. The two adjacent arch column parts of the three arched suture frames are merged into support rods. The lower parts of the three support rods are retracted inward to form the tail of the internal stent for the tether to pass through and be fixed. The arched interiors of the three arched suture frames are all provided with X-shaped connecting frames.

[0007] As a further improvement, the tops of the three arched suturing frames are each provided with a suturing limiting hole, and the suturing limiting hole is arranged on the outer side or the inner side of the top of the arched suturing frame.

[0008] As a further improvement, the three arched suturing frames adopt a smooth skeleton structure or a wavy skeleton structure, and the upper parts of the three arched suturing frames are evenly distributed.

[0009] As a further improvement, the skeleton widths of the arched suturing frame and the X-shaped connecting frame are both 0.3-2.0 mm, and the width of the support rod is twice the width of the arched suturing frame.

[0010] As a further improvement, the support rod is provided with a fixed row of holes or a fixed ring groove for connecting with the outer bracket.

[0011] As a further improvement, the inward angle of the lower part of the support rod is 10-50°.

[0012] As a further improvement, the tail portion formed by the inward retraction of the lower portions of the three support rods further comprises an upper bent connecting rod and a lower bent connecting rod connecting the ends of the three support rods, and the upper bent connecting rod and the lower bent connecting rod form a hexagonal or diamond-shaped tail clamping structure with the support rods; or,

[0013] The tail portion formed by the inward retraction of the lower portions of the three support rods is configured as a diamond-shaped clamping structure formed by connecting the middle of the forked rods after the end portions of the three support rods are forked.

[0014] As a further improvement, the tail portion is provided with a suture hole for suturing the tether to the inner bracket.

[0015] As a further improvement, the inner support is an integrated structure made of nickel-titanium alloy or nitinol alloy.

[0016] As another improvement of the present invention, the present invention also provides a heart valve replacement prosthesis, which includes the inner stent of the above-mentioned heart valve replacement prosthesis.

[0017] After adopting such a design, the present invention has at least the following advantages:

[0018] 1. The internal stent of the heart valve replacement prosthesis of the present invention improves upon the suturing frame used to sew the bioprosthesis together, replacing the existing six support rods with only three. This significantly increases the space between the support rods. Furthermore, the provision of an X-shaped connecting frame ensures sufficient rigidity of the internal stent, forming a tail structure that does not squeeze or obstruct the outflow tract while maintaining the rigidity of the internal stent, thereby effectively resolving outflow tract obstruction.

[0019] 2. The three arched suture frames plus the three X-shaped connecting frames not only ensure the uniform distribution of the inner bracket structure and make production and processing easier, but also make the stress distribution of the inner bracket more reasonable, the fatigue resistance stronger and the service life longer.

[0020] 3. In addition, the diamond-shaped or hexagonal clamping structure design at the tail of the inner bracket not only has a large gap in the middle, but also makes it easy to squeeze and sew the tether, thereby ensuring a firm connection between the inner bracket and the tether.

[0021] 4. The inner stent of the heart valve replacement prosthesis of the present invention has better production and processing stability and higher yield rate, whether in the heat setting stage or in the valve suturing, stent assembly and tether assembly stages, which greatly reduces the cost; and it is not easy to be confused when formulating the surgical plan, and the product selection is more accurate and convenient. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The above is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0023] Figure 1 It is a schematic side view of the structure of the inner stent of the existing heart valve replacement prosthesis.

[0024] Figure 2 It is a schematic top view of the structure of the inner stent of the existing heart valve replacement prosthesis.

[0025] Figure 3 It is a schematic diagram of the three-dimensional structure of the inner stent of the heart valve replacement prosthesis of the present invention.

[0026] Figure 4 It is a schematic front view of the structure of the inner stent of the heart valve replacement prosthesis of the present invention.

[0027] Figure 5It is a schematic side view of the structure of the inner stent of the heart valve replacement prosthesis of the present invention.

[0028] Figure 6 It is a schematic top view of the structure of the inner stent of the heart valve replacement prosthesis of the present invention.

[0029] Figure 7 It is a structural schematic diagram of the horizontally expanded state of the inner stent of the heart valve replacement prosthesis of the present invention after the tube is laser cut.

[0030] Figure 8 It is a schematic front view of the structure of Example 2 of the inner stent of the heart valve replacement prosthesis of the present invention.

[0031] Figure 9 This is a schematic structural diagram of the laser-cut tube of the second embodiment of the inner stent of the heart valve replacement prosthesis of the present invention.

[0032] Figure 10 This is a schematic structural diagram of a second embodiment of the inner stent of a heart valve replacement prosthesis according to the present invention in a horizontally deployed state after laser cutting of the tube.

[0033] Figure 11 It is a schematic front view of the structure of Example 3 of the inner stent of the heart valve replacement prosthesis of the present invention.

[0034] Figure 12 This is a schematic structural diagram of the inner stent embodiment 3 of the heart valve replacement prosthesis of the present invention after the tube is laser cut.

[0035] Figure 13 This is a schematic structural diagram of the inner stent embodiment 3 of the heart valve replacement prosthesis of the present invention in a horizontally deployed state after the tube is laser cut.

[0036] Figure 14 It is a schematic front view of the structure of a fourth embodiment of the inner stent of a heart valve replacement prosthesis according to the present invention. DETAILED DESCRIPTION

[0037] This invention improves upon the existing stent structure of a heart valve replacement prosthesis by reducing its six support rods to three. This significantly increases the space between the rods, creating a tail structure that prevents compression and obstruction of the outflow tract while ensuring the rigidity of the stent, thereby resolving the technical issue of easily obstructed outflow tracts. Specific embodiments are as follows.

[0038] Example 1

[0039] The heart valve replacement prosthesis of this embodiment includes an outer stent, an inner stent, a tether, and an apical pad. The outer stent and the inner stent are connected and assembled, the inner stent and the tether are connected and assembled by crimping and suturing, and the tether and the apical pad are connected and assembled by needle threading.

[0040] Refer to the attached Figures 3 to 6 As shown, the stent of the heart valve replacement prosthesis of this embodiment utilizes a cylindrical frame structure formed by three arched suturing frames 1. The adjacent arches of the three arched suturing frames 1 merge into support rods 2. The lower portions of the three support rods 2 are retracted to form the stent's tail section 3, through which the tether is passed and secured. Each of the three arched suturing frames 1 is provided with an X-shaped connecting frame 4 within the arched portion. The three arched suturing frames 1 are primarily used to suture bioprosthetic valves, such as bovine pericardium, porcine pericardium, or porcine aortic valves. However, with the development of new technologies, the use of synthetic materials instead of biomaterials has become increasingly feasible, so the stent's suturing frame 1 can also suturing synthetic materials. The three X-shaped connecting frames 4 divide and connect the arched suturing frame 1 at the head and waist, creating four diamond-like structures from top to bottom. This not only helps maintain the overall cylindrical shape of the stent, increasing its rigidity and resisting deformation, but also ensures uniform size of the three arched suturing frames 1 during heat treatment, making it easier to form and less prone to breakage, thus providing a more advantageous manufacturing and processing advantage. The three arched suturing frames 1 combined with the three X-shaped connecting frames 4 provide the structure with sufficient rigidity to protect the sutured valve from external loads, such as compression, during the cardiac cycle, thereby maintaining the valve's shape and enabling billions of opening and closing cycles. Furthermore, because only three support rods are tightened, the tail portion has ample free space, preventing obstruction or compression of the outflow tract, resulting in excellent application results.

[0041] In this embodiment, the biological valve is cut into three valves of the same size. The three biological valves are sutured to the three-arch suture frame 1 using specific needles and sutures, and their lower edges are also sutured to the support rod 2. Since the skeleton surface of the arch suture frame 1 is smooth, the biological valve can easily slide along the skeleton curve of the suture frame, resulting in positional displacement, which ultimately makes the product unusable. Therefore, in this embodiment, the tops of the three arch suture frames 1 are all provided with suture limiting holes 5. During the valve suturing process, the suture limiting holes 5 are also sutured together with the biological valve, so that the biological valve will not move on the arch suture frame 1. Of course, the skeleton structure of the arch suture frame can also adopt a wavy line shape to reduce the sliding of the biological valve.

[0042] In this embodiment, the suture-limiting holes 5 can be located on the outer side of the top of the arched suture frame 1, forming an antenna-like suture-limiting hole. The suture-limiting holes 5 can be circular, elliptical, square, or diamond-shaped. The three arched suture frames 1 are evenly distributed on their upper portions to better match the heart valve structure.

[0043] The arched suturing frame 1 and the X-shaped connecting frame 4 both have a frame width of 0.3-2.0 mm, preferably 0.5 mm. If the frame is too narrow, it will lack rigidity and easily deform; if it is too wide, it will be too rigid, making it difficult to heat-set and hindering suturing. The support rod 2 is twice the width of the arched suturing frame and is the thickest and strongest section of the internal support structure, providing important support for maintaining overall rigidity.

[0044] The support rod 2 is also provided with a row of fixing holes (not shown) for connecting to the outer bracket. When assembling the inner and outer brackets, the inner and outer brackets can be connected by inserting the foot pins of the outer bracket into the row of fixing holes. Of course, the support rod 2 can also be provided with a fixing ring groove, and the outer bracket can be tied to the support rod 2 using wire or suture to achieve the connection between the inner and outer brackets. It is also possible to directly weld the pins of the outer bracket to the support rod 2 to achieve the fixation of the outer bracket.

[0045] In this embodiment, the lower part of the support rod 2 is retracted inward, forming a funnel-shaped structure with a large head and a small tail of the inner stent. The angle of the retraction of the lower part of the support rod 2 relative to the horizontal plane is preferably 10-50°, preferably 30°. The size of this angle directly affects the overall length of the inner stent. The larger the angle, the longer the inner stent; the smaller the angle, the shorter the inner stent. If the inner stent is too long, the tail end may contact the inner wall of the left ventricle during cardiac movement, affecting myocardial function or interfering with the chordae tendineae; if the angle is too small, it will lead to poor stress conduction, causing stress concentration, causing premature damage to the prosthesis, and reducing the life of the prosthesis. Therefore, choosing a suitable intersection angle has a great impact on the use effect and service life of the inner stent.

[0046] In this embodiment, the tail portion 3 formed by the inward retraction of the lower portion of the three support rods 2 is configured as a diamond-shaped clamping structure formed by connecting the middle of the bifurcated rods after the end portions of the three support rods 2 are forked. Whether during laser cutting or heat setting, the tail structure can be large or small, has high redundancy, and can be changed freely and arbitrarily. Compared with the tail of the inner bracket of the tendyne product, this structure is much easier to heat set and does not pose a risk of breakage. The tail of the tendyne is too crowded, and when it is stored and set, if you are not careful, it may cause part of the skeleton to break, seriously affecting the yield rate. Moreover, when the structure is fixed with the tether, it is very easy to expand the hole. After the tether is installed and slightly heated, the diamond-shaped clamping structure will shrink and the tether can be clamped. At the same time, another important feature of this structure is that the gap in the middle is very large. After the tether is clamped, the material after the tether is squeezed will fill these gaps. Even without suturing, the tether is difficult to fall out of the inner bracket. If the tether of the Tendyne product is not sutured, it is very easy to fall out of the inner bracket.

[0047] To further ensure a secure connection between the tether and the inner support, the tail portion 3 is provided with a suture hole 6 for sewing the tether to the inner support. The suture hole 6 can be circular, oval, square, or diamond-shaped. Of course, when suturing the inner support and the tether, in addition to suturing through the suture hole 6, it is also possible to sew through the gap of the diamond-shaped clamping structure.

[0048] The inner bracket in this embodiment is made of nickel-titanium alloy or nitinol alloy, preferably nickel-titanium alloy, which is a memory metal with memory properties. The main steps of the one-piece molding of the inner bracket are: laser cutting of the tube, removal of residues, heat setting, and polishing. Among them, the design of the laser cutting diagram is crucial. Figure 7 The embodiment shows the state of the stent tube after being laser cut and then flattened, so as to fully express its structure more clearly.

[0049] The inner stent of the heart valve replacement prosthesis of this embodiment improves its suture frame structure, changing the existing suture frame with 6 support rods into only 3 support rods, greatly increasing the space between the support rods, and through the setting of the X-shaped connecting frame, the sufficient rigidity of the inner stent is ensured, forming a tail structure that will not squeeze or block the outflow tract, while ensuring the rigidity of the inner stent, achieving the purpose of truly solving the problem of outflow tract obstruction and ensuring the long-term stability of the valve.

[0050] Example 2

[0051] The difference between this embodiment and the above-mentioned embodiment 1 is that Figures 8 to 10 As shown, the suturing limiting hole 5 is arranged on the inner side of the top of the arched suturing frame 1 to form a hanging ring type suturing limiting hole.

[0052] The other parts of this embodiment are the same as those of the above embodiment and will not be described again here.

[0053] Example 3

[0054] The difference between this embodiment and the above-mentioned embodiment 1 is that Figures 11 to 13 As shown, the tail portion 3 formed by the inward retraction of the lower portions of the three support rods 2 includes an upper bent connecting rod 31 and a lower bent connecting rod 32 that connect the lower ends of the three support rods 2. The upper and lower bent connecting rods 31, 32, and the support rods 2 form a hexagonal tail clamping structure, which can also be a diamond-shaped tail clamping structure. This structure does not change the width of the original support rods, ensuring the strength of the support rods. The bent connecting rods also form an expandable and retractable tail clamping structure, which is simple in structure and easy to manufacture.

[0055] The other parts of this embodiment are the same as those of the above embodiment and will not be described again here.

[0056] Example 4

[0057] The difference between this embodiment and the above-mentioned embodiment 3 is that Figure 14 As shown, the suturing limiting hole 5 is arranged on the inner side of the top of the arched suturing frame 1 to form a hanging ring type suturing limiting hole.

[0058] The other parts of this embodiment are the same as those of the above embodiment and will not be described again here.

[0059] In the description of the present invention, it should be noted that the terms "upper", "lower", "front", "back", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and 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. Therefore, they cannot be understood as limiting the present invention.

[0060] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0061] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Those skilled in the art can make some simple modifications, equivalent changes or modifications based on the technical content disclosed above, which all fall within the scope of protection of the present invention.

Claims

1. An inner stent of a heart valve replacement prosthesis, characterized in that: A cylindrical frame structure is formed by three arched suturing frames, wherein the adjacent arched columns of the three arched suturing frames are combined to form support rods, and the lower parts of the three support rods are retracted to form the tail of the inner bracket for the tether to pass through and fix. The arched interiors of the three arched suturing frames are all provided with X-shaped connecting frames; The tail formed by the inward retraction of the lower parts of the three support rods further includes an upper bent connecting rod and a lower bent connecting rod connecting the ends of the three support rods, and the upper bent connecting rod and the lower bent connecting rod form a hexagonal or diamond-shaped tail clamping structure with the support rods; or, The tail portion formed by the inward retraction of the lower portions of the three support rods is configured as a diamond-shaped clamping structure formed by connecting the middle of the forked rods after the end portions of the three support rods are forked.

2. The inner stent of the heart valve replacement prosthesis according to claim 1, characterized in that: The tops of the three arched suturing frames are each provided with a suturing limiting hole, and the suturing limiting hole is arranged on the outer side or the inner side of the top of the arched suturing frame.

3. The inner stent of the heart valve replacement prosthesis according to claim 1, characterized in that: The three arched suturing frames adopt a smooth skeleton structure or a wavy skeleton structure, and the upper parts of the three arched suturing frames are evenly distributed.

4. The inner stent of the heart valve replacement prosthesis according to claim 3, characterized in that: The skeleton widths of the arched suturing frame and the X-shaped connecting frame are both 0.3-2.0 mm, and the width of the support rod is twice the width of the arched suturing frame.

5. The inner stent of the heart valve replacement prosthesis according to claim 4, characterized in that: The support rod is provided with a fixed row of holes or a fixed ring groove for connecting with the outer bracket.

6. The inner stent of the heart valve replacement prosthesis according to claim 1, characterized in that: The inward angle of the lower part of the support rod is 10-50 degrees.

7. The inner stent of the heart valve replacement prosthesis according to claim 1, characterized in that: The tail portion is provided with a suture hole for suturing the tether to the inner bracket.

8. The inner stent of the heart valve replacement prosthesis according to any one of claims 1 to 7, characterized in that: The inner support is an integrated structure made of nickel-titanium alloy.

9. A heart valve replacement prosthesis, characterized in that: An inner stent comprising the heart valve replacement prosthesis according to any one of claims 1 to 8.

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