Presettable artificial aortic valve

Abstract

A presettable biological prosthetic aortic valve includes a valve seat (1), a leaflet stent (2), and three leaflets (3) attached to the leaflet stent (2), in which the valve seat (1) is an annular metal seat that can be expanded with a position limit in one direction, and a first rivet (7), a position limiting protrusion (6), and a first oval groove (5) are provided at the tip of each seat body unit (4) in this order from outside to inside, and a second oval groove (8) that engages with the first rivet (7) at the tip of the adjacent seat body unit (4), a second position limiting hole (10) and a first position limiting hole (9) that respectively engage with the position limiting protrusion (6), and a second rivet (11) that engages with the first oval groove (5) are provided at the end of each seat body unit (4) in this order. The presettable biological prosthetic aortic valve has an initial preset state and a normal use state after being expanded with a position limit in one direction.

Description

Technical Field

[0001] The present invention relates to an artificial biological valve, and particularly to a presetable artificial biological aortic valve.

Background Art

[0002] With the surgical progress of valves, aortic valve replacement (AVR) has become increasingly important in dealing with problems such as stenosis of the valve annulus or the root of the aorta. For AVR patients mainly suffering from stenosis such as congenital heart disease or rheumatic heart disease, those with a small build or too large body weight, those with stenosis of the valve annulus or combined stenosis of the left ventricular outflow tract or poor formation of the root of the aorta (sinotubular junction - valve annulus - outflow tract), due to being restricted by the local anatomical conditions at the root of the aorta, an artificial valve with a sufficient diameter cannot always be introduced. Using an undersized artificial valve prosthesis in surgery will cause problems such as high postoperative inter-valve pressure difference in patients, inability to improve hemodynamics, and increased subsequent left ventricular load, which not only affects the recovery of the patient's cardiac function, but also affects the long-term quality of life and survival rate, and accelerates the deterioration of the biological valve.

[0003] Patients in China have a particularly serious problem of artificial valve - patient mismatch (PPM) because their body types are smaller than those of Westerners. According to data from 93 large-scale centers in the Chinese Cardiac Surgery Registry System, recently 50% of surgical AVR patients have transplanted small-sized artificial valves not exceeding size 21. Therefore, cardiac surgeons in China first have to expand the valve annulus surgically before performing AVR. Expanding the valve annulus or the root of the aorta is an effective way to solve a small aortic annulus, but it has high requirements for the surgeon's surgical technique, postoperative complications occur, and ultimately many patients die. In fact, some patients are suitable for using biological valves but are worried about the relatively small aortic valve annulus, and have no choice but to select the same type of mechanical valve due to reasons such as being older or having anticoagulation contraindications.

[0004] Furthermore, with recent research and application of transcatheter valve intervalves, it has become feasible to introduce a single transcatheter prosthetic valve into a previously implanted and damaged bioprosthetic valve via a catheter, allowing these patients to receive treatment without the risk of undergoing further surgery to replace the valve. However, the specifications of the previously implanted damaged valve are often too small, for example, size 21 or 19, which limits the inner diameter of the valve orifice and makes intervention with transcatheter valve intervalve therapy difficult. Even if a relatively small valve intervalve is intervened, the intervalve pressure difference is high postoperatively, significantly affecting its durability. Currently, the industry has not yet proposed a satisfactory solution. [Overview of the project]

[0005] In view of the above, the present invention can provide a presettable artificial bioprosthetic aortic valve having an initial preset state, the appearance of which is one size smaller than conventional surgically implanted artificial bioprosthetic heart valves, and after the implantation surgery is completed, it can be rotated in one direction by balloon pressurization and the inner diameter of the valve orifice can be enlarged by 1 or 1.5 sizes by positional constraint, thereby avoiding the risk of PPM and obtaining a better therapeutic effect.

[0006] To solve the above technical problems, the present invention employs a presettable artificial biological aortic valve comprising a valve seat, a valve leaf stent, and three valve leaves attached to the valve leaf stent, wherein the valve seat is an annular metal seat that can be expanded by positioning in one direction, and the annular metal seat consists of a seat unit in which three tips and ends are connected alternately on the inside and outside, with a first rivet, a position-limiting projection, and a first oval groove provided at the tip of each seat unit in order from the outside to the inside, and a second oval groove that engages with the first rivet of the tip of the adjacent seat unit, a second position-limiting hole and a first position-limiting hole that engage with the position-limiting projection, and a second rivet that engages with the first oval groove provided at the end of each seat unit in order. Each seat unit has a first oval groove that engages with a second rivet of an adjacent seat unit, allowing it to move in one direction; each seat unit has a second oval groove that engages with a first rivet of an adjacent seat unit, allowing it to move in one direction; each seat unit has a position-limiting projection that engages with a first position-limiting hole and a second position-limiting hole of an adjacent seat unit, allowing it to move in one direction; each seat unit has a wavy projection in the middle; the presettable artificial bio-aortic valve has an initial state in which it is preset and a normal use state in which it is position-limiting and expanded in one direction; each seat unit expands outward by synchronous unidirectional rotation and then forms a normal use state similar to that of a conventional surgical bio-aortic valve.

[0007] Here, each valve seat unit is expanded by a balloon of 5 atmospheres or more (atm) to synchronously rotate the valve seat in one direction and expand outward, forming an expanded state that is restricted to the position in that direction. The valve leaf stent has a preset state and a normal application state, the preset state matches the valve seat before expansion, and the normal function state matches the valve seat after expansion. The structure of each seat unit is exactly the same, and the tip of each seat unit is positioned inside the end of the adjacent seat unit. The position restriction projection has a semicircular projection that slopes upward along the expansion direction. The projection has a circular head along the expansion direction to suppress forward sliding resistance and stabilize it, and a flat tail prevents sliding in the reverse direction after sliding into the position restriction hole. The position restriction hole has a shape that matches the position restriction projection. If the position-restricting projections on the valve seat are located at two positions, before and after expansion of the valve seat, the valve frame corresponds to two shapes, before and after expansion, with the post-expansion shape being the normal-use shape. The valve leaflet stent has a preset shape and a normal-use shape, the normal-use shape matching the normal-use state after the presetable artificial biological aortic valve has been expanded with position restriction in one direction. The specifications of the three valve leaflets match the normal-use state after the aortic valve has been expanded with position restriction in one direction. The outside of the valve seat is covered with a support belt made of polymerized material, the support belt matching the normal-use state after the aortic valve has been expanded with position restriction in one direction. The valve leaflets are denatured bovine pericardium, porcine pericardium, porcine aortic valve, sheet-like animal tissue, or non-biosynthetic valve leaflet material. When the valve portion consisting of the three valve leaflets is in the normal-use state after the unidirectional expansion with position restriction, it allows unidirectional blood flow through the valve portion. The materials for the valve seat and valve leaf stents are Elgiloy alloy, cobalt-chromium alloy, nickel-titanium alloy, and implantable stainless steel (316L, cobalt-chromium-nickel-molybdenum-iron alloy).Before the valve is positioned and expanded in one direction, the initial preset state is an abnormal state of use. The valve can only exert its unidirectional blood flow valve action when it moves from an expanded state, positioned and expanded in one direction, to a normal state of use similar to that of a conventional surgical bioprosthetic aortic valve due to the external force of the balloon.

[0008] The present invention relates to a presetable artificial bioprosthetic aortic valve prosthesis. The artificial heart valve, which can be expanded with unidirectional positional restriction, has two states. The first state of the product is the preset state, in which the implanted outer diameter of the product resembles the appearance of previously commercially available nominal artificial bioprosthetic heart valve products, but the specification model number is smaller, either 1 or 1.5, and this type is the valve model number corresponding to the annular size. In this state, the valve is not usable and is not in an operational state. After the product is implanted in a patient's relatively small aortic annulus or relatively small aorta root, the product can be expanded with unidirectional positional restriction by external force from balloon pressurization, entering a second state in which it can be used normally. That is, the morphology, structure, and performance are exactly the same as artificial bioprosthetic heart valves already commercially available from companies, only the specification model number of 1 or 1.5 is enlarged, and in this state the valve is in a fully normal functional state. As will be seen, this process allows patients whose aortic annulus is originally too small to be implanted with a bioprosthetic valve, or who are concerned about valve size mismatch (PPM), to first implant a small annular valve and then expand the annulus by balloon dilation after implantation, thereby achieving the ultimate effect and objective of implanting a relatively large valve. The main meaning of "presetting" is to first implant a relatively small, abnormally used valve and then expand it. Expanding the annulus not only brings benefits to the treatment of the valve itself (e.g., a reduction in intervalve pressure difference), but also opens up possibilities for future transcatheter valve treatment in such patients with small aortic root surgical valve replacement. [Brief explanation of the drawing]

[0009] [Figure 1] Figure 1 is a schematic fluoroscopic view of a presetable artificial biological aortic valve body according to an embodiment of the present invention. [Figure 2] Figures 2A-E are schematic diagrams of the initial and expanded states of the valve seat in Figure 1. [Figure 3] Figure 3 is an exploded view of the three seat units of the valve seat shown in Figure 1. [Figure 4] Figure 4 is an unfolded view of the initial state after the three seat units of the valve seat in Figure 1 have been joined together. [Figure 5] Figure 5 is an unfolded view of the expanded state after the three seat units of the valve seat in Figure 1 have been joined together. [Figure 6] Figures 6A-B are schematic diagrams illustrating the unidirectional movement of the valve seat and the expansion of the valve seat's diameter position limitation. [Figure 7] Figures 7A-C show schematic diagrams of the initial preset state and the normal use state in which the artificial bio-aortic valve of the present invention is expanded in one direction by the external force of balloon intervention. [Figure 8] Figures 8A-B are schematic diagrams of a predictable artificial aortic valve implantation surgery according to an embodiment of the present invention. [Figure 9] Figures 9A-B are schematic diagrams illustrating how to accurately measure the initial and unidirectional internal diameters of the aortic valve, which are preset by DSA angiography. [Modes for carrying out the invention]

[0010] The present invention will be described in more detail below with reference to the drawings and embodiments. The specific embodiments described herein are for interpretation purposes only and do not limit the present invention.

[0011] Referring to Figures 1-7, an embodiment of the present invention is a presetable artificial biological aortic valve comprising a valve seat 1, a valve leaf stent 2, and three valve leaves 3 attached to the valve leaf stent, wherein the valve seat is an annular metal seat that can be expanded by positioning in one direction, and the annular metal seat consists of a seat unit 4 in which three tips and ends are connected alternately inward and outward, with a first rivet 7, a position-limiting projection 6, and a first oval groove 5 provided in order at the tip of each seat unit, and a second oval groove 8, a first position-limiting hole 9, and a second position-limiting hole 1 at the end. A first oval groove 5 of each seat unit 4 engages with the second rivet 11 of the adjacent seat unit and is movable in one direction, and a second oval groove 8 of each seat unit engages with the first rivet 7 of the adjacent seat unit and is movable in one direction, and a semicircular position-restricting projection 6 of each seat unit engages with the semicircular first position-restricting hole 9 and second position-restricting hole 10 of the adjacent seat unit and is movable in one direction, and each seat unit has a wavy projection in the middle. In the initial state, the position-restricting projection 6 is first positioned in the second position-restricting hole 10, and after being restricted and expanded in one direction, the position-restricting projection 6 is displaced in one direction and positioned in the first position-restricting hole 9. The position-restricting projection has a semicircular projection that inclins upward along the expansion direction. The projection has a circular head along the expansion direction, which suppresses forward sliding resistance and stabilizes it, and a flat tail portion prevents sliding in the reverse direction after sliding into the position-restricting hole. The position-restricting hole has a shape that matches the position-restricting projection. When the position-restricting projection is located at two positions on the valve seat, before and after expansion, the valve frame corresponds to the two shapes before and after expansion, with the post-expansion shape being the normal-use shape. The presettable artificial bio-aortic valve has a preset initial state and a normal-use state after expansion with position restriction in one direction. Each seat unit expands outward by synchronous unidirectional rotation and then forms a normal-use state similar to that of a conventional surgical bio-aortic valve. Figures 2A and 2C show the initial state, and Figures 2B and 2D show the post-expansion state.Furthermore, the arrangement of the oval grooves and rivets is not fixed; their positions can be changed as needed, and they only need to cooperate to restrict rotational expansion in one direction.

[0012] Referring to Figures 6 and 7, each seat unit is expanded by a balloon of 5 atmospheres (atm) or more, causing the valve seat to rotate synchronously in one direction and expand outward to form an expanded state that is restricted to the position in that direction. The valve leaf stent has a preset state and a normal application state, with the preset state matching the valve seat before expansion and the normal function state matching the valve seat after expansion. Each seat unit has the exact same structure, and its tip is positioned inside or outside the end of an adjacent seat unit. The position restriction projection has a semicircular projection that slopes upward along the expansion direction, and the position restriction hole has a shape that matches the position restriction projection. The position restriction projection has a circular head along the expansion direction, which suppresses forward sliding resistance and stabilizes it, and a flat tail portion prevents sliding in the reverse direction after sliding into the position restriction hole. The position-restricting holes have a shape that matches the position-restricting projections, and when the position-restricting projections are located at two positions on the valve seat, before and after expansion, the valve frame corresponds to the two shapes before and after expansion, the post-expansion shape is the normal-use shape, and the lengths of the first and second oval grooves coincide with the distance between the two position-restricting holes. The valve leaflet stent has a preset form and a normal-use form, the normal-use form matching the normal-use state after the presetable artificial biological aortic valve has been expanded with position restriction in one direction. The specifications of the three valve leaflets match the normal-use state after the expanded state with position restriction in one direction. The outside of the valve seat is covered with a support belt made of polymerized material, the support belt matching the normal-use state after the expanded state with position restriction in one direction of the aortic valve. The valve leaflets are modified bovine pericardium, porcine pericardium, porcine aortic valve, sheet-like animal tissue, or non-biosynthetic valve leaflet material. The valve portion, consisting of the three leaflets, allows unidirectional blood flow through the valve portion when in a normal operating state after being expanded and restricted to one direction. The materials for the valve seat and leaflet stent are Elgiloy alloy, cobalt-chromium alloy, nickel-titanium alloy, and implantable stainless steel (316L, cobalt-chromium-nickel-molybdenum-iron alloy). The outer layer material of the above covering is prior art in this field and is not shown.Before the valve is in an expanded state with its position restricted to one direction, the initial preset state is an abnormal state of use. When the valve is moved from an expanded state with its position restricted to one direction by the external force of the balloon to a normal state of use similar to that of a conventional surgical aortic valve, it can exert a valve action that allows for unidirectional blood flow. In vitro verification

[0013] The presettable artificial bio-aortic valve according to the present invention is characterized by having an initial preset state and a normal operating state that is expanded in one direction by an external force of balloon intervention (see Figure 7). In in vitro testing, a normal balloon is used to expand the valve by balloon intervention, and when it reaches 5 atmospheres, the aortic valve is expanded in one direction from the initial preset state, increasing the inner diameter by one type and setting it as the normal operating state. Compared to the company's original commercially available artificial bio-aortic valve, even when measuring with a limited external diameter and after in vitro hydrodynamic testing, its external appearance is exactly the same as its hydrodynamic performance. Internal verification

[0014] Adult sheep were used as experimental animals, and artificial bioprosthetic aortic valves that could be pre-set in situ were implanted under extracorporeal circulation. Implantation surgeries were performed on valves No. 19, 21, and 23 (see Figures 8 and 9). The outer diameter of the valve was measured by DSA before dilation, and then a balloon for valve dilation intervention was inserted, pressurized to 5.0-5.5 atmospheres, maintained for 5 seconds, then the pressure was released, the balloon was removed, and the heart and chest skin were sutured in order to complete the surgery.

[0015] Using DSA contrast imaging, the inner diameter of the implanted and expanded preset aortic valve was accurately measured (see Figure 9). Next, esophageal ultrasound was used to measure the intervalve pressure difference, effective opening area, and regurgitation status of the valve. When compared with the company's commercially available artificial aortic valves, the normal operation of the unidirectional expanded, preset artificial aortic valve was exactly the same as the opening and closing function of a larger model of commercially available artificial aortic valve.

[0016] The animal experiments completed a total of three different models, all of which similarly achieved unidirectional expansion of the preset aortic valve using balloon inflation pressure, converted from their initial state to a normal operating state, and showed no valve regurgitation by esophageal ultrasound. The inner diameter and effective opening area were both the same as those of a normal prosthetic aortic valve of the next larger model.

[0017] The design of preset aortic valves provides patients requiring surgical valve replacement for aortic stenosis, where the valve annulus or root of the aorta is narrow, with a model one size smaller in outer diameter. However, balloon expansion allows for obtaining a normal valve one or 1.5 sizes larger. At the same time, it avoids the need to implant a preset prosthetic aortic valve of a larger specification in patients whose original aortic annulus is too small to be implanted with a bioprosthetic valve, or in whom PPM is a concern, due to complications from root widening surgery. Simultaneously, it also addresses the possibility that the patient may require transcatheter valve therapy in the future.

[0018] The foregoing are merely preferred embodiments of the present invention and do not limit it. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should all be included within the scope of protection of the present invention.

Claims

1. A presettable artificial bioaortic valve comprising a valve seat, a leaflet stent, and three leaflets attached to the leaflet stent, The valve seat is an expandable annular metal seat that restricts movement in one direction, and the annular metal seat consists of three seat units whose front and back ends are connected in an alternating overlapping manner, with a first rivet, a position-restricting projection, and a first oval groove provided at the front of each seat unit in order from the outside to the inside, and a second oval groove that engages with the first rivet at the front of the adjacent seat unit, a second position-restricting hole and a first position-restricting hole that engage with the position-restricting projection, and a second rivet that engages with the first oval groove, in that order, Each seat unit has a first oval groove that engages with a second rivet of an adjacent seat unit, allowing it to move in one direction; each seat unit has a second oval groove that engages with a first rivet of an adjacent seat unit, allowing it to move in one direction; each seat unit has a position-restricting projection that engages with a first position-restricting hole and a second position-restricting hole of an adjacent seat unit, allowing them to move in one direction; and each seat unit has a wavy projection in the middle. The presettable artificial aortic valve has a preset initial state and a normal operating state in which movement is restricted in one direction and it is expanded, and each seat unit expands outward by synchronous unidirectional rotation to form a normal operating state similar to that of a conventional surgical aortic valve. Before the valve, consisting of the three leaflets, is in an expanded state with movement restricted in one direction, the initial preset state is an abnormal state of use. When the valve, which is expanded with movement restricted in one direction by the external force of the balloon, moves to a normal state of use similar to that of a conventional surgical bioprosthetic aortic valve, it exerts a valve action that allows blood flow in one direction. A presettable artificial biological aortic valve characterized by the following features.

2. The front end of each seat unit is positioned inside the end of the adjacent seat unit. The presetable artificial biological aortic valve according to feature 1.

3. Each of the aforementioned seat units is expanded by a balloon of 5 atmospheres or more, causing the valve seat to rotate synchronously in one direction and expand outward, forming an expanded state in which movement in that one direction is restricted. The valve leaf stent has a preset state and a normal application state, the preset state matches the state of the valve seat before expansion, and the normal function state matches the state of the valve seat after expansion. The presetable artificial biological aortic valve according to feature 1.

4. The position-restricting projection has a semicircular projection that is inclined upward along the expansion direction, and the position-restricting hole has a shape that matches the position-restricting projection. The presetable artificial biological aortic valve according to feature 1.

5. The position-restricting projection has a semicircular projection that inclins upward along the expansion direction, and the position-restricting projection has a circular head along the expansion direction to suppress forward sliding resistance and stabilize, and a flat tail to prevent sliding in the reverse direction after sliding into the position-restricting hole, and the position-restricting hole has a shape that matches the position-restricting projection, and when the position-restricting projection is located at two positions on the valve seat, before and after expansion, the valve frame corresponds to the two shapes before and after expansion, and the shape after expansion is the normal operating shape. The presetable artificial biological aortic valve according to feature 1.

6. The length of the first oval groove, the length of the second oval groove, and the distance between the two position limiting holes are all the same. The presetable artificial biological aortic valve according to feature 1.

7. The valve leaflet stent has a preset configuration and a normal use configuration, the normal use configuration matching the normal use state after the presetable artificial biological aortic valve has been expanded with its movement restricted in one direction. The presetable artificial biological aortic valve according to feature 1.

8. The specifications of the three aforementioned petal leaves are matched to the normal operating state after they have been expanded with movement restricted in one direction. The presetable artificial biological aortic valve according to feature 1.

9. The outer surface of the valve seat is covered with a support belt made of a polymerized material, and the support belt matches the normal operating state after the aortic valve has expanded while restricting movement in one direction. The presetable artificial biological aortic valve according to feature 1.

10. The valve leaflets are modified bovine pericardium, porcine pericardium, porcine aortic valve, sheet-like animal tissue, or non-biosynthetic valve leaflet material. The presetable artificial biological aortic valve according to feature 1.

11. When the valve portion consisting of the three valve leaves is in a normal state of use after being expanded with restricted movement in one direction, it allows unidirectional blood flow through the valve portion. The presetable artificial biological aortic valve according to feature 1.

12. The materials for the valve seat and valve leaf stents are cobalt-chromium alloy, nickel-titanium alloy, and implantable stainless steel. The presetable artificial biological aortic valve according to feature 1.

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