A one-way positionally restricted and expandable prosthetic bioprosthetic heart valve

Abstract

The artificial heart valve includes a valve seat (1), a leaflet stent (2), and three leaflets (3) attached to the leaflet stent (2), and is expandable in one direction with limited positioning. The valve seat (1) includes an annular metal seat (4) that is expandable in one direction with limited positioning. The annular metal seat (4) is made of three seat body units (5) whose leading ends and trailing ends are alternately stacked one on top of the other and connected together. The leading end of each seat body unit (5) is provided with a first rivet (8), a position limiting protrusion (7), and a first and an oval groove (6) is provided in sequence at the end of each base body unit (5), and a second oval groove (9) that engages with a first rivet (8) at the tip of an adjacent base body unit (5), a second position limiting hole (11) and a first position limiting hole (10) that respectively engage with the position limiting protrusion (7), and a second rivet (12) that engages with the first oval groove (6), so that the artificial heart valve has an initial state for normal use and an expanded state in which its position is limited in one direction.

Description

[Technical field]

[0001] The present invention relates to the field of prosthetic heart valves, and in particular to unidirectionally confined and expandable biological heart valve prostheses. [Background technology]

[0002] According to the US guidelines for the treatment of valvular heart disease, artificial biological valves outside China are mainly applied to patients with valvular heart disease aged 70 years or older, and more than 75-80% of patients with valvular heart disease in most developed countries have had their valves replaced through surgery and have selected and implanted artificial biological heart valves (bovine pericardial biological valves or porcine aortic valves). Traditionally, patients with valvular heart disease aged 50 years or younger are prone to early valvular calcification after implantation of various biological valves, and face the risk of having to undergo another centrifugal operation to replace the valve. The guidelines suggest that patients with valvular heart disease aged 50 years or younger should select and implant an artificial mechanical valve, but for patients with valvular heart disease aged 50-70 years, depending on the specific circumstances of the patient, for example, patients with contraindications for coagulation, it is suggested that a biological valve be selected. Unlike many elderly aortic valve degenerative lesions in the United States, many valvular disease patients in China today suffer from rheumatic valvular disease, most of which are mainly mitral valve degenerative lesions, with multiple valvular lesions at the same time, and the disease is relatively serious and progresses quickly. Most patients must undergo surgery to replace the valve before the age of 65, so patients in China can only choose artificial mechanical valves. However, patients after mechanical valve surgery need anticoagulation for the rest of their lives, and a large number of evidence-based medical data show that anticoagulation-related complications after mechanical valve surgery are the most direct cause of endangering the postoperative quality of life and actual survival rate of these patients, and have not been solved until now. For a long time, about 80% or more of valvular disease patients in China have had no choice but to choose artificial mechanical valves for transplantation.

[0003] In recent years, with the research and application of transcatheter valve-in-valve, it has become feasible to introduce a transcatheter artificial biological valve into a previously implanted damaged biological valve via a catheter, so that these patients can obtain treatment without the risk of undergoing surgery to replace the valve again. However, due to the limited inner diameter of the valve orifice of the damaged valve, only a small size of transcatheter valve-in-valve can be accommodated. In many cases, especially in some patients in China who have been implanted with a slightly small size biological valve due to their height or body type, only a relatively small size of valve-in-valve can be intervened, and clinical data shows that the transvalve pressure difference is relatively high after the relatively small size of transcatheter valve-in-valve operation, and its durability is also significantly affected. Therefore, Edwards Lifesciences Corporation of the United States disclosed an expandable artificial heart valve in September 2013, and the invention is called "Structure of surgical heart valve expandable after implantation" (Chinese patent application number is 201380067967.5). The artificial heart valve has an expandable structure when first implanted to replace the native valve, and can assume an expanded form, for example, by balloon expansion. The invention provides various expandable structures, and the product, INSPIRIS RESILIA aortic valve, was also officially approved for use in the Chinese domestic market by the China National Medical Products Administration in December 2020 (see Figure 1).

[0004] In view of the above, expandable biological valves usually need to be expanded when they need to be intervened in a valve-in-valve procedure after calcification or damage has occurred for many years after implantation in the body. Usually, after a long period of 10 to 15 years after surgery, if the valve is covered by perivalve fibrosis after implantation or calcification occurs around the valve at the preset possible dehiscence site, the valve is difficult to expand again by a balloon as preset, and in the practice of extracardiac secondary valve replacement surgery, it is difficult to expand again a damaged biological valve that has been solidified by perivalve lesions (see Figure 2).

[0005] Therefore, the expansion action in the aforementioned Chinese patent application number 201380067967.5 "Structure of surgical heart valve expandable after implantation" is entirely radial expansion, which has the following problems as shown in FIG. 3:

[0006] (1) The radial expansion force of the balloon is fully utilized to radially expand the valve seat, and the required expansion force is large, which is difficult to achieve in actual surgery or involves high unexpected risks.

[0007] (2) Because it expands completely radially, the tissue resulting from the expansion of the valve seat size expands radially in a large area, and the excessive expansion of the base of the valve leaflets significantly increases the probability of surrounding conduction block.

[0008] Generally, the need for expansion of surgical prosthetic valves occurs several years after the implantation of the valve, and at this time, in most cases, the tissues surrounding the valve are partially or completely calcified, and the degree of calcification varies from person to person. At this time, if the calcified tissue is expanded entirely using radial expansion force, not only will a large balloon internal pressure be required, but there is also a risk that the tissues surrounding the valve will be damaged by calcification (e.g., the root of the aorta). The circumferential shear force at this time not only has the potential to move the calcified part in the circumferential direction, but is also likely to form larger shear damage to the calcified furnace itself, reducing its rigidity and ultimately causing damage. All of these effects are favorable to reducing the balloon internal pressure, which reduces the impact of calcification on the new valve transplant. Summary of the Invention

[0009] The present invention provides a unidirectionally positionally limited and expandable prosthetic biological heart valve, whose initial structure and appearance are completely the same as those of the conventional surgically implanted prosthetic biological heart valve. However, if the valve is damaged due to calcification or other reasons several years after implantation, the balloon can be used to apply an external force to rotate and feed (shear force) along the circumference of the damaged valve in one direction, and the valve seat units can be pushed and extended in one direction in sequence, rotating and enlarging the diameter of the damaged valve. By designing the dimensions of the oval grooves in each seat unit, the unidirectionally positionally limited and enlarged inner diameter of a type of valve orifice can be accommodated according to the original structure, thereby providing patients with better treatment and eliminating the later concerns of many patients in China who choose a biological valve.

[0010] The present invention relates to a unidirectionally expandable artificial heart valve prosthesis, which has two states, and the first state of the product is completely the same as the appearance and performance of the artificial biological heart valve that has been launched by the company for 18 years. The difference is that the unidirectionally expandable artificial heart valve can have a second state due to the structural design described in the claims. That is, the unidirectionally expandable artificial heart valve prosthesis, like all conventional artificial heart valves that are implanted in the heart to replace diseased valves, will suffer from valvular damage due to various causes many years after the patient's operation, and will be used for transcatheter valves. When valve treatment is required, the valve seat unit of the limited-position expandable prosthetic heart valve is sequentially slid and stretched by the action of external force caused by pressurization of the balloon, and the circumferential length of the valve seat is rotated and advanced, and the inner diameter of the valve seat is expanded. Even if the valve seat is wrapped or embedded in the perivalve tissue lesion, the unidirectional limited-position expandable prosthetic heart valve can enter a second state, that is, the valve seat expands in one specification size, and the specification size of the valve in the next transcatheter valve introduced through the catheter is still close to the inner orifice area of ​​the original valve seat, so that the patient can obtain a better treatment effect.

[0011] A specific technical solution of the present invention is a unidirectionally positionally limited and expandable artificial heart valve, comprising a valve seat, a leaflet stent, and three leaflets attached to the leaflet stent, the valve seat comprising an annular metal seat which is unidirectionally positionally limited and expandable, the annular metal seat being made up of three seat body units connected in an alternating overlapping manner, the tip of each seat body unit being provided in order with a first rivet, a position limiting protrusion and a first oval groove, the end of each seat body unit being provided with a second oval groove which engages with the first rivet at the tip of an adjacent seat body unit, a second position limiting hole and a first position limiting hole which respectively engage with the position limiting protrusion, and a third position limiting hole which engages with the first oval groove, the third position limiting hole and the fourth position limiting hole which engage with the first oval groove, the fourth ... two rivets are arranged in sequence, the first oval groove of each seat body unit is engaged with the second rivet of an adjacent seat body unit to be movable in one direction, the second oval groove of each seat body unit is engaged with the first rivet of an adjacent seat body unit to be movable in one direction, the position limiting protrusion of each seat body unit is engaged with the second position limiting hole and the first position limiting hole of an adjacent seat body unit to be movable in one direction respectively, the artificial heart valve has an initial state for normal use and an expanded state limited in one direction, and each seat body unit forms an expanded state limited in one direction after being expanded outward by synchronous unidirectional rotation.

[0012] Here, the seat body unit may be two or four or more. The tip of each seat body unit is disposed inside the end of the adjacent seat body unit. Each seat body unit is expanded by a balloon of 5 atmospheres (atm) or more to rotate the valve seat synchronously in one direction and expand outward to form the expanded state limited in position in one direction, and the initial state is the initial state of the full-circumference annulus structure. The structure of each seat body unit is completely the same, and the tip is disposed inside or outside the end of the adjacent seat body unit. The position limiting protrusion has a semicircular protrusion inclined upward along the expansion direction, and the position limiting hole has a shape matching the position limiting protrusion. The length of the first and second oval grooves is consistent with the distance between the two position limiting holes. The specifications of the three leaflets match the initial state. The outside of the valve seat is covered with a support belt made of a polymeric material, and the support belt matches the initial state. The leaflets are modified bovine pericardium, porcine pericardium, porcine aortic valve, sheet animal tissue or non-biosynthetic leaflet material. The three-leaflet valve portion allows unidirectional blood flow through the valve portion when in an initial structure. The material of the valve seat is Elgiloy alloy, cobalt chromium alloy, nickel titanium alloy and implantable stainless steel (316L, cobalt chromium molybdenum iron alloy). After the valve leaflets are in an expanded state with limited position in one direction, the function of the original valve leaflets is lost, and the expanded valve seat structure firmly accommodates a new valve leaflet-transcatheter midvalve that is intervened via a catheter in any manner. The valve leaflets are aortic, mitral or tricuspid. When the valve leaflets are aortic, each seat unit has a wavy protrusion in the middle. When the valve leaflets are mitral or tricuspid, each seat unit has a protrusion in the middle of the upper side and is flat on the lower side.

[0013] The unidirectionally positionally limited expandable artificial heart valve of the present invention is composed of two or more, preferably three identical valve seat units. The tips and ends of the three parts are connected via rivets and grooves, and are surrounded to form a valve frame structure. When the inner diameter needs to be expanded, the valve seat is radially expanded using an expansion balloon larger than the inner diameter of the valve seat, and the moving parts of the three structures all slide along the same circumferential direction (clockwise or counterclockwise at the same time). As a result, the surrounding tissues are subjected to a shear force generated by the relative displacement tendency of the valve seat due to the fixed rotation with respect to the surrounding tissues, in addition to the radial expansion force due to the outward expansion.

[0014] In contrast, the prior art patent examples also have designs using a sliding expansion inner diameter of the groove in the valve seat, but the various parts of the structure do not support unidirectional sliding or extension of the valve support frame, and the expandable cardiac valve structure described in the invention has surrounding tissues that are mainly subjected to radial expansion forces during the expansion process.

[0015] Considering the surrounding mechanical and material environment and its effect on the native annulus or perivalve tissue, the advantages of the unique directional rotational expansion of the unidirectionally constrained expandable prosthetic heart valve of the present invention are as follows:

[0016] (1) The radial expansion force of the balloon is fully utilized to radially expand the valve seat, and the radial expansion force and the circumferential shear force against the surrounding tissue are simultaneously utilized to directional rotate the valve seat. When the same valve seat inner diameter expansion dimension is reached (for example, when the inner diameter expands from 23 mm to 25 mm), the balloon inner pressure (radial expansion force) required to directional rotate and expand the valve seat is smaller.

[0017] (2) Because the surrounding tissue is compressed circumferentially, the radial expansion of the tissue due to the expansion of the valve seat size is relatively reduced compared to complete radial expansion, which effectively reduces the probability of the base of the valve leaflet expanding excessively and causing surrounding conduction block.

[0018] (3) The need for expansion of surgical prosthetic valves generally occurs after several years of valve implantation, at which point the tissues surrounding the valve have already been partially or completely calcified in most cases, with the degree of calcification varying from person to person. At this time, if the calcified tissue is expanded entirely using radial expansion force, not only will a large balloon pressure be required, but there is also a risk that the tissues surrounding the valve will be damaged by calcification (e.g., the root of the aorta). The circumferential shear force at this time not only has the potential to move the calcified part in the circumferential direction, but is also likely to form larger shear damage to the calcified furnace itself, reducing its rigidity and ultimately causing damage. All of these effects are favorable to reducing the balloon pressure, which reduces the impact of calcification on new valve implantation.

[0019] Therefore, regardless of the expansion mechanism and the effect of expansion, the unidirectionally confined expandable prosthetic heart valve described in the present invention is fundamentally different from the design structure and expansion mechanism described in the cited documents, and is not covered by any of the prior art examples. [Brief description of the drawings]

[0020] [Figure 1] 1A-C are schematic diagrams of Edwards' expandable valve product of the prior art. [Diagram 2] FIG. 2 is a schematic diagram of a damaged tissue valve engulfed or solidified by perivalvular lesions. [Diagram 3] FIG. 3 is a schematic diagram of a valve seat of an expandable valve leaflet in the prior art. [Figure 4] FIG. 4 is a schematic diagram of a unidirectionally constrained expandable bioprosthetic mitral / tricuspid valve according to an embodiment of the present disclosure. [Diagram 5] 5A-E are schematic diagrams of the valve seat in FIG. 4 in an initial state and an expanded state. [Figure 6] FIG. 6 is an exploded view of the valve seat unit in FIG. [Figure 7] FIG. 7 is a schematic development view of the valve seat unit in FIG. 4 in an initial state. [Figure 8]FIG. 8 is a schematic development view of the valve seat unit in FIG. 4 in an expanded state. [Figure 9] FIG. 9 is a schematic diagram of the unidirectional movement of the seat body unit and the restricted expansion of the valve seat diameter. [Figure 10] FIG. 10 is a perspective schematic diagram of a unidirectionally constrained expandable biological aortic valve prosthesis according to an embodiment of the present application. [Figure 11] 11A-D are schematic diagrams of the valve seat in FIG. 10 in an initial state and an expanded state. [Figure 12] 12A-B are assembled and exploded schematic diagrams of a unidirectionally constrained expandable aortic valve according to an embodiment of the present invention. [Figure 13] 13A-B are assembled and exploded schematic views of a unidirectionally constrained expandable mitral valve in accordance with an embodiment of the present invention. [Figure 14] 14A-B show that balloon-mediated pressurized intravalvulation can accommodate a transcatheter in-valve that is exactly the same diameter as the native valve leaflet. [Figure 15] 15A-C are schematic diagrams of inner diameter measurements before and after expansion of one-way restricted expansion prosthetic biocardial valves implanted in situ in experimental animals with different valve positions. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] The present invention will be described in more detail below with reference to the drawings and examples. Note that the specific examples described herein are merely for the purpose of interpreting the present invention and are not intended to limit the present invention. Example 1 Schematic diagram of a unidirectionally positionally restricted and expandable prosthetic mitral / tricuspid valve

[0022] 4 to 8, which are schematic diagrams of a prosthetic mitral / tricuspid valve that can be expanded with one-way positional constraint according to an embodiment of the present application, the main structure includes a valve seat 1, and three leaflets 3 are provided on the valve seat 1 via a leaflet stent 2, which is almost the same as the structure of a commonly seen prosthetic mitral valve. The valve seat 1 includes an annular metal seat 4 that can be expanded with one-way positional constraint, and a support belt 13 that is wrapped around the annular metal seat 4.

[0023] Here, the annular metal seat is composed of three seat body units 5 whose front ends and end ends are alternately stacked inside and outside and connected to each other. The front end of each seat body unit 5 is provided with a first rivet 8, a position limiting protrusion 7 and a first oval groove 6, in that order, and the end is provided with a second oval groove 9, a second position limiting hole 11, a first position limiting hole 10 and a second rivet 12, in that order. When connected to each other, the front end of each seat body unit is located on the inside and the end is located on the outside. The first oval groove 6 of each seat body unit can be engaged with the second rivet 12 of the adjacent seat body unit to move in one direction, the second oval groove 9 of each seat body unit can be engaged with the first rivet 8 of the adjacent seat body unit to move in one direction, and the semicircular position limiting protrusion 7 of each seat body unit can be engaged with the second position limiting hole 10 and the first position limiting hole 11 of the adjacent seat body unit to move in one direction. In the initial state, the position limiting protrusion 7 is first positioned in the second position limiting hole 11, and then expanded in one direction with position limiting, and the first rivet and the second anchor rotate in one direction in their respective oval grooves, expand and move, and the position limiting protrusion 7 is displaced in one direction into the first position limiting hole 10 and positioned there, forming an expanded state, and can be firmly positioned in the expanded state by the action of the position limiting hole (see FIG. 5E). Note that the arrangement of the oval groove and the rivet is not fixed, and their positions can be changed as necessary, as long as they cooperate with each other to realize the unidirectional rotational expansion movement.

[0024] The artificial heart valve has an initial state for normal use and an expanded state limited in one direction, and each seat unit is expanded outward by synchronous unidirectional rotation to form the expanded state limited in one direction. Each seat unit has a completely identical structure, and its tip is located inside or outside the end of the adjacent seat unit. The position limiting protrusion 7 is a semicircular protrusion inclined upward along the expansion direction, and the position limiting hole has a shape matching the position limiting protrusion, which allows the seat unit to rotate in only one direction and ensures that the valve seat does not return to its original state after expansion. The length of the first oval groove, the length of the second oval groove, and the distance between the two position limiting holes are the same. The specifications of the three leaflets match the initial state. The outside of the valve seat is covered with a support belt made of a polymeric material, and the support belt matches the initial state. The leaflets are modified bovine pericardium, porcine pericardium, porcine aortic valve, sheet-like animal tissue, or non-biosynthetic leaflet material. The three-leaflet valve portion allows unidirectional blood flow through the valve portion when in the initial structure. The materials of the valve seat are Elgiloy alloy, cobalt chrome alloy, nickel titanium alloy and implantable stainless steel (316L, cobalt chrome nickel molybdenum iron alloy). After the valve leaflets are in a unidirectionally restricted expanded state, the original valve structure is lost and the new valve leaflets-transcatheter valve-in-valve are firmly accommodated by any method of intervention through a catheter. The center of each seat unit has a wavy protrusion. Referring to FIG. 9, after the valve seat unit is rotated and expanded outward, the valve seat expands and a new valve-in-valve can be implanted.

[0025] In some cases, the seat body units of the valve seat may be configured symmetrically in two or in four or more, either of which can be limited in position in one direction to achieve an expandable function. Example 2: Unidirectionally positionally restricted and expandable prosthetic aortic valve

[0026] 10-11, which are schematic diagrams of a one-way position-restricted expandable prosthetic biological aortic valve, the structure of which is almost the same as that of the mitral valve / tricuspid valve in the previous embodiment, with the main difference being that the middle of each seat unit has a wavy protrusion. Referring to FIG. 11, when the valve seat unit rotates and expands outward, the valve seat expands and a new valve-in-valve can be implanted. In vitro validation

[0027] The one-way position-restricted expandable prosthetic biological heart valve of the present invention is divided into aortic (FIG. 12), mitral (FIG. 13) and tricuspid (the valve seat structure is completely the same as that of the mitral valve). When the inside is expanded by balloon intervention pressurization, whether it is aortic, mitral or tricuspid, the valve seat unit will slide in one direction sequentially by the balloon pressure expansion, and the circumference of the valve seat will be extended to the next larger model (FIG. 4), so that it can accommodate the transcatheter valve with the same diameter as the original valve. In vivo verification

[0028] In vivo verification of the one-way position-restricted expandable artificial heart valve according to the present invention, adult sheep were used as experimental animals, and the one-way position-restricted expandable artificial heart valve was implanted in situ in extracorporeal circulation. The experimental sheep were operated on to implant the aortic, mitral and tricuspid valves. At 1 day, 3 days, 1 week, 11 weeks and 22 weeks after the operation, the inner diameter of the implanted valve was accurately measured by DSA angiography (FIG. 14A). Then, the balloon was inserted into the product of the present invention at three different valve positions through the femoral artery or apex puncture or the femoral vein, and the balloon was pressurized by connecting to a pressure pump to expand the product of the present invention in one direction (FIG. 14B). When the pressure indication reached 5.5 atmospheres, the pressure was continuously reduced for 5 seconds, and the inner diameter of the valve orifice was measured and recorded again (FIG. 14C).

[0029] A total of 41 animal experiments were completed, including 32 experimental animals in the mitral valve position, 5 in the tricuspid valve position, and 4 in the aortic valve position. The corresponding transplant valve specifications were M23, T25, and A21 position-restricted expandable biological valves, and expansion under position restriction was completed by DSA using balloons of the corresponding sizes. In all cases, expansion of 2 mm under position restriction was completed, reaching the size specifications of M25, M27, and A23 (Figure 14D).

[0030] The above are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention should be included within the protection scope of the present invention. [Explanation of symbols]

[0031] 1 valve seat, 2 valve leaflet stent, 3 valve leaflet, 4 annular metal seat, 5 seat body unit, 6 first oval groove, 7 position limiting protrusion, 8 first rivet, 9 second oval groove, 10 first position limiting hole, 11 second position limiting hole, 12 second rivet, 13 support belt.

Claims

1. A unidirectionally positionally confined and expandable prosthetic heart valve including a valve seat, a leaflet stent, and three leaflets attached to the leaflet stent, The valve seat includes an annular metal seat that can be expanded in one direction with its position limited, and the annular metal seat is composed of three seat body units whose leading ends are alternately stacked and connected, and the leading end of each seat body unit is sequentially provided with a first rivet, a position limiting protrusion, and a first oval groove, and the trailing end of each seat body unit is sequentially provided with a second oval groove that engages with the first rivet at the leading end of an adjacent seat body unit, a second position limiting hole and a first position limiting hole that respectively engage with the position limiting protrusion, and a second rivet that engages with the first oval groove, the first oval groove of each seat body unit is engaged with the second rivet of the adjacent seat body unit to be movable in one direction, the second oval groove of each seat body unit is engaged with the first rivet of the adjacent seat body unit to be movable in one direction, and the position limiting protrusion of each seat body unit is engaged with the second position limiting hole and the first position limiting hole of the adjacent seat body unit to be movable in one direction, The artificial heart valve has an initial state for normal use and an expanded state in which its position is restricted in one direction, and each of the seat units is expanded outward by synchronous unidirectional rotation and then forms the expanded state in which its position is restricted in one direction; the position limiting protrusion has a semicircular protrusion inclined upward along the expansion direction, the position limiting hole has a shape matching the position limiting protrusion, and 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 tip of each seat unit is disposed inside the end of the adjacent seat unit, and the material of the valve seat is Elgiloy alloy, cobalt chromium alloy, nickel titanium alloy or implantable stainless steel. A prosthetic heart valve capable of being expanded with its position restricted in one direction.

2. The seat body unit is two or four or more pieces.

2. The prosthetic heart valve according to claim 1, wherein the prosthetic heart valve is expandable with one-way positional constraint.

3. Each seat unit is inflated by a balloon of 5 atmospheres or more to rotate the valve seat synchronously in one direction and expand outward, thereby forming the expanded state limited in one direction, and the initial state is the initial state of the circumferential annulus structure.

2. The prosthetic heart valve according to claim 1, wherein the prosthetic heart valve is expandable with one-way positional constraint.

4. The specifications of the three leaflets are matched with the initial state; 2. The prosthetic heart valve according to claim 1, wherein the prosthetic heart valve is expandable with one-way positional constraint.

5. The valve seat further includes a support belt made of a polymeric material, the support belt is coated on the outside of the annular metal seat, and the support belt matches the initial state.

2. The prosthetic heart valve according to claim 1, wherein the prosthetic heart valve is expandable with one-way positional constraint.

6. The valve leaflets are modified bovine pericardium, porcine pericardium, porcine aortic valve, sheet-like animal tissue, or non-bio-synthetic valve leaflet material.

2. The prosthetic heart valve according to claim 1, wherein the prosthetic heart valve is expandable with one-way positional constraint.

7. the three-leaflet valve portion, when in an initial state, allows unidirectional blood flow through the valve portion; 2. The prosthetic heart valve according to claim 1, wherein the prosthetic heart valve is expandable with one-way positional constraint.

8. After the valve leaflets are in a unidirectionally restricted expanded state, the original valve leaflets lose their function, and the expanded valve seat structure firmly accommodates a new valve leaflet - a transcatheter valve - inserted via a catheter in any manner.

2. The prosthetic heart valve according to claim 1, wherein the prosthetic heart valve is expandable with one-way positional constraint.

9. The valve is an aortic valve, a mitral valve, or a tricuspid valve.

2. The prosthetic heart valve according to claim 1, wherein the prosthetic heart valve is expandable with one-way positional constraint.

10. When the valve leaflet is an aortic valve, each seat body unit has a wavy protrusion in the middle.

2. The prosthetic heart valve according to claim 1, wherein the prosthetic heart valve is expandable with one-way positional constraint.

11. When the valve leaflet is a mitral valve or a tricuspid valve, each of the seat body units has a protrusion at the center of the upper side and a flat lower side.

2. The prosthetic heart valve according to claim 1, wherein the prosthetic heart valve is expandable with one-way positional constraint.

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