Background
The heart contains four chambers, the Right Atrium (RA), right Ventricle (RV), left Atrium (LA), and Left Ventricle (LV). The pumping action on the left and right sides of the heart generally occurs simultaneously throughout the cardiac cycle. The valve separating the atrium from the ventricle is called the atrioventricular valve, which acts as a one-way valve, ensuring the normal flow of blood in the heart chamber. The atrioventricular valve between the left atrium and the left ventricle is the mitral valve and the atrioventricular valve between the right atrium and the right ventricle is the tricuspid valve. The pulmonary valve directs blood flow to the pulmonary artery and from there to the lungs, where it returns to the left atrium via the pulmonary veins. The aortic valve directs blood flow through the aorta and from there to the periphery. There is typically no direct connection between the ventricles or between the atria.
At the beginning of ventricular filling (diastole), the aortic and pulmonary valves close to prevent regurgitation from the arterial into the ventricles. Shortly thereafter, the atrioventricular valves open to allow unimpeded flow from the atria into the respective ventricles. Shortly after the onset of ventricular systole (i.e., ventricular emptying), the tricuspid and mitral valves are normally closed, thereby forming a seal that prevents regurgitation from the ventricles into the respective atria.
When the atrioventricular valve is problematic, it cannot function normally, resulting in improper closure. Atrioventricular valves are complex structures that generally include an annulus, leaflets, chordae tendineae and a support structure. Each atrium is connected to its valve through the atria vestibule. The mitral valve has two leaflets and a similar structure of the tricuspid valve has three leaflets, and the attachment or engagement of the respective surfaces of each leaflet to each other helps provide closure or sealing of the valve, preventing blood flow in the wrong direction. Failure of the leaflets to seal during ventricular systole, known as malacia, can allow reverse flow (regurgitation) of blood through the valve. Insufficiency of the heart valve can have serious consequences for the patient, often resulting in heart failure, reduced blood flow, reduced blood pressure, and/or reduced oxygen flow to the human tissue. Mitral insufficiency can also cause blood to flow from the left atrium back into the pulmonary veins, causing congestion. Severe valve insufficiency, if left untreated, can lead to permanent disability or death.
Left ventricular outflow obstruction is mainly caused by thickening of the ventricular septum and asymmetric thickening of the ventricular septum of a patient suffering from hypertrophic cardiomyopathy, which results in narrowing of the outflow path when the left ventricle shoots outwards. The heart is contracted and blood passes through the narrow place, because the strength of the narrow place is very large, and the primary valve leaflets are replaced or repaired to the two sides, the strength can attract the primary mitral valve to the ventricular septum, so that the narrow place is more serious, and the primary valve leaflets can also completely block the blood flowing out path at the later stage of the heart contraction, so that left ventricular outflow obstruction is formed. Common symptoms of left ventricular outflow tract obstruction are palpitation, shortness of breath, debilitation, angina pectoris, fainting, angina pectoris attacks, and heart failure in late stages.
Thrombus is a small block of blood flow formed on the surface of the inside surface of a cardiovascular system vessel where it is exfoliated or repaired. In variable fluid dependence, the thrombus consists of insoluble fibrin, deposited platelets, accumulated leukocytes and entrapped erythrocytes. When the inner membrane is damaged, endothelial cells are denatured, necrotic and shed, and collagen fibers below the endothelium are exposed, so that factor XII of an endogenous blood coagulation system is activated, the damaged inner membrane can release tissue blood coagulation factors, and the exogenous blood coagulation system is activated. The damaged intima becomes roughened, causing the platelets to aggregate easily, adhering primarily to bare collagen fibers.
In recent years, the field of artificial valves has been developed with some breakthrough, but due to the complexity of the mitral valve and its surrounding structures, mitral valve treatment still faces great challenges, such as 1, how to solve the deposition of blood flow at the connection site of the leaflet and the stent, avoiding thrombosis there, 2, how to reduce the diameter of the device delivering the valve, thereby reducing the wound area during implantation, and 3, how to avoid the outflow tract of the native valve She Duzhu, and solve the outflow tract obstruction problem.
Disclosure of Invention
The present invention provides a prosthetic valve prosthesis that addresses the above-described deficiencies in the prior art.
The technical scheme of the invention is as follows:
a prosthetic valve prosthesis comprises a stent body and a leaflet assembly,
The support main body is including constructing to have latticed frame construction's first support and second support, first support has the link, wherein, the second support includes a plurality of support poles, and a plurality of the support pole is fixed in respectively the link of first support, the valve leaf subassembly is furnished with first valve leaf fixed part, first valve leaf fixed part is fixed in the link of first support.
Compared with the prior art that the stent main body is of a frame structure consisting of a plurality of closed geometric units, the first stent is of a grid-shaped frame structure so as to ensure that the stent main body can be compressed into the conveying device, the second stent is mainly composed of a plurality of stent rods, so that the material of the stent main body is reduced, the cross-sectional area of the conveying device is reduced, the wound area of a patient is reduced, in addition, the region clamped by the valve leaflet component and the second stent is far away from the first stent, the stent structure at the position is relatively sparse, blood is not easy to deposit at the position, and therefore the risk of thrombosis is reduced. In addition, the sparse stent structure also helps to reduce the risk of outflow tract obstruction or obstruction when the second stent is anchored in the ventricle.
In some embodiments, the first leaflet retainer is configured to have an extension curve that matches the connecting end such that the first leaflet retainer coincides with the connecting end. At this time, the region clamped by the leaflet assembly and the stent body and far from the first stent side is completely a sparse structure formed by the stent rods, so that blood can be prevented from depositing in the region.
In some embodiments, the stent rod is fixed to an end (one end or both ends) of the connecting end, or the stent rod is disposed in a manner configured between two adjacent leaflets. Preferably, when the leaflet assembly is configured with a plurality of leaflets, the junction between two adjacent leaflets is configured as a second leaflet fixing portion, and the leaflet assembly is further fixed on the bracket rod by the second leaflet fixing portion. By the structure, the support rod can provide a fixed position for the valve leaflet, corresponding acting force is provided for opening and closing the valve leaflet, two adjacent valve leaflets are fixed to the support rod at the joint through the second valve leaflet fixing part, the opening amplitude of the valve leaflet is reduced, and the acting force of beating tissues when the valve leaflet opens is reduced, so that the service life of the valve leaflet is prolonged.
Further, the number of the bracket rods is at least 2, preferably 2-5. Too many, the material of can increase the support main part of bracket, increase conveyor's cross-sectional area to can increase the wound area, the support pole quantity is too little, can't provide sufficient stationary force for the lamella to guarantee that the lamella is smooth to open and close.
In some embodiments, the stent rod is configured to have a first end portion fixed with the first stent, the stent rod further having a leaflet attachment portion for fixing a leaflet, a distance between the leaflet attachment portion and an end face of the first end portion being 1/12 to 1/2 of a length of the stent rod. Because the area of the first bracket is larger, the valve leaflet is sewed on the second bracket rod close to the first bracket, which is beneficial to the first bracket to share the acting force of the valve leaflet on the bracket rod and increases the durability of the bracket rod.
Preferably, the first end portion is configured in a columnar shape or a horn shape, when the first end portion is configured in a horn shape, the support rod and the first support frame can be smooth and excessive, the force applied to the support rod can be uniformly dispersed on the whole first support frame, and the durability of the support main body is improved. Further, the leaflet attachment part is configured as a number of suture holes, preferably circular holes, the number of suture holes being 1-10, preferably 2-5.
In some embodiments, the free end of at least one of the support rods is configured as a hook for hooking the native leaflet, which secures the native leaflet, prevents the native leaflet She Du from plugging the outflow tract, and can also be used to hook tissue, functioning as an anchor. Preferably, at least two of the stent rods in the second stent are provided with the hooks, wherein the hooks are arranged symmetrically, so that the native valve leaflet can be more effectively fixed, and the anchoring to the stent body is more stable.
In some embodiments, the second bracket makes an angle γ of 10-175 °, preferably γ of 90-160 °, with the first bracket. At this angle, the first stent may be tightly coupled to the atrium, which may provide adequate anchoring sites for the stent.
In some embodiments, the second stent further comprises a leaflet cutter for cutting the native leaflet, the leaflet cutter dissecting the native mitral valve and being hooked by stent struts on both sides, avoiding the native valve She Duzhu from exiting the tract.
Preferably, the leaflet cutting member is fixed at the connecting end of the first bracket and positioned between two adjacent bracket rods, so that the native leaflet can be fixed by the hook parts of the bracket rods at two sides after being cut.
In some embodiments, the leaflet cutting member is configured to extend in a direction away from the leaflet assembly, and the angle α between the leaflet She Qiege member and the direction in which the stent rod extends is 0-90 °, and further preferably, the angle α is 0-45 °. The design can ensure that the valve leaflet cutting piece cuts the primary valve leaflet before the support rod hooks the primary valve leaflet, so that an oversized primary valve She Duzhu can be prevented from flowing out of the channel, and meanwhile, the angle can ensure that the valve leaflet cutting piece does not interfere with the normal opening and closing of the replacement valve leaflet.
In some embodiments, the leaflet cutting member is configured with cutting portions that are triangular, square, or have rounded cutting edges.
The cutting portion is disposed from the free end of the leaflet cutting member toward the other end thereof, preferably, a plurality of the cutting portions are disposed in a continuous manner along a direction in which the leaflet cutting member extends, or a plurality of the cutting portions are disposed in a discontinuous manner therebetween.
In some embodiments, the prosthetic valve prosthesis is used to replace a diseased native leaflet, such as replacement of the anterior or posterior leaflet of a mitral valve, or repair of a tricuspid, aortic valve, the stent body is configured in a non-occluded configuration and when the prosthetic valve is used to replace a native valve, the stent body is configured in a circumferentially-occluded annular configuration.
Compared with the prior art, the invention has the following beneficial effects:
First, the prosthetic valve prosthesis of the invention, the second stent mainly consists of a plurality of stent rods, the valve leaflet assembly is fixed on the second stent, compared with the stent body in the prior art which is a frame structure consisting of a plurality of closed geometric units, the stent rods of the invention reduce the material of the stent body, thereby reducing the cross-sectional area of a delivery device, and further reducing the trauma area of a patient, in addition, the valve leaflet assembly and the second stent are clamped at a region far away from the first stent, blood is not easy to deposit at the region, thus reducing the risk of thrombosis, and in addition, when the second stent is anchored in a ventricle, the structure of the stent rods helps to reduce the blockage or obstruction of an outflow channel.
Second, the prosthetic valve prosthesis of the present invention, the connecting end of the first stent is constructed to have an arc matching with the leaflet fixing end, the first leaflet fixing portion is completely overlapped with the connecting end of the first stent after the leaflet assembly is fixed, and the region sandwiched between the leaflet assembly and the second stent is completely a relatively sparse structure composed of stent rods at a side far away from the first stent, so that blood is not deposited there, further reducing the risk of thrombosis, and simultaneously, further reducing the material of the stent body, and reducing the cross-sectional area of the delivery device.
Thirdly, the artificial valve prosthesis comprises a free end of a bracket rod, a second bracket and a valve blade cutting piece, wherein the free end of the bracket rod is also provided with a hook part for hooking a primary valve blade to form a retention force for the primary valve blade, so that the primary valve She Du is prevented from plugging a flow channel in the heart contraction process and can be used for hooking tissues to play a certain anchoring role, and the second bracket is also provided with a valve blade cutting piece which can cut the primary valve blade and is hooked by bracket rods at two sides to avoid larger primary valve She Duzhu from flowing out of the channel.
Of course, it is not necessary for any of the products embodying the invention to achieve all of the advantages set forth above at the same time.
Detailed Description
In the description of the present invention, it should be noted that the directions or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, are merely for convenience of describing the present invention and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
In the description of the present invention, unless explicitly stated or limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected, mechanically connected, electrically connected, directly connected, indirectly connected via an intervening medium, or in communication between two elements. The specific meaning of the above terms in the present invention will be understood in specific cases by those of ordinary skill in the art.
As used in this specification, the singular forms "a", "an" and "the" include plural referents unless the content clearly dictates otherwise. As used in this specification, the term "or" is generally employed in its sense including "and/or" unless the content clearly dictates otherwise.
The invention will be further illustrated with reference to specific examples.
Example 1
This embodiment provides a prosthetic valve prosthesis (also referred to as a valve prosthesis), see fig. 1A-6D, comprising a stent body and a leaflet assembly 130. The stent body may serve as a supporting structure of the leaflet assembly 130, and may also serve as an anchoring function for anchoring with tissue, a function of connecting with a delivery device (e.g., one end or both ends of the stent body are provided with a hanging tab or a fixing tab), etc. The prosthetic valve prosthesis of this embodiment is a transcatheter delivered valve prosthesis that is compressed into a delivery device for delivery during implantation, released and anchored after delivery to the target site. Wherein, the stent main body adopts biocompatible materials such as nickel titanium or cobalt chromium, the valve leaflet component 130 comprises at least one artificial valve leaflet, and according to actual clinical requirements, a corresponding number of artificial valve leaflets can be arranged, and the artificial valve leaflet can be biological tissues such as bovine pericardium, porcine pericardium, horse pericardium and the like.
Referring to fig. 1A, the stent body includes a first stent 110 and a second stent 120 configured to have a lattice-shaped frame structure, the first stent 110 having a connection end 210, and the first stent 110 being connected to the second stent 120 through the connection end 210. The second bracket 120 includes a plurality of bracket rods 121, the bracket rods 121 are respectively fixed at the connection ends 210 of the first bracket 110, the leaflet assembly 130 is configured with a first leaflet fixing portion 134, and the first leaflet fixing portion 134 is fixed at the connection ends 210 of the first bracket 110.
Wherein the first stent 110 is configured as a lattice-like frame structure composed of an array of several closed geometric cells including, but not limited to, triangles, squares, pentagons, drops, hearts, diamonds, etc., preferably composed of an array of diamond-shaped cells, such that the first stent 110 may be compressed into a delivery catheter for delivery, and upon release thereof, the first stent 110 self-expands to return to its original shape. The stent rod 121 may be fixed at the vertex of the diamond-shaped cell or at the edge of the diamond-shaped cell of the first stent 110 so that the entire stent body may be compressed while being self-expanding.
In the prior art, the whole bracket main body is a frame structure formed by arranging a plurality of closed geometric units, see fig. 2, which is a partial structure schematic diagram of the bracket main body in the prior art, and comprises an upper flaring, a lower ventricular upper part, a lower ventricular middle part and a lower ventricular lower part, wherein the upper flaring is anchored in an atrium, a valve leaflet is fixed in the lower ventricular middle part of the bracket main body, the lower ventricular lower part is positioned in the ventricle, and blood flows in from the upper flaring and flows out from the lower ventricular lower part. After the valve leaflet is fixed, a region is clamped at the connecting part of the frame structure and the valve leaflet and at one side close to the lower part of the lower ventricle, and the region is easy for blood deposition and thrombus formation.
To address the problem of thrombus formation, the prior art generally subjects the blood-contacting material to an anti-thrombotic treatment to reduce thrombus formation, but there is still a risk of thrombus formation. At the same time, how to reduce the material of the valve prosthesis and thus the diameter of the delivery device is a big challenge.
Unlike the structure of the stent body in the prior art and the technical concept for solving thrombosis, the stent body of the present embodiment includes a first stent 110 and a second stent 120, wherein the second stent 120 includes a plurality of stent rods 121 fixed at the connecting ends 210 of the first stent, and the rod-shaped structure of the stent rods 121 enables the second stent 120 to be formed into a relatively sparse stent structure. Unlike the prior art where the middle of the lower ventricle and the lower portion of the lower ventricle are both grid-like frame structures, the second stent 120 of the present embodiment does not form a staggered network in the direction perpendicular to the direction in which the stent rods extend. The relatively sparse structure of the second stent 120, where the leaflet assembly 130 joins the stent body and is distal to the side of the first stent 110, makes blood less likely to deposit in this region, reducing the risk of thrombus formation in this region. At the same time, the structure of the second stent 120 also reduces the material of the stent body, thereby reducing the cross-sectional area of the delivered valve prosthesis, and thus the trauma area of the patient.
Further, when the first stent 110 is mainly anchored in the atrium and the second stent 120 is anchored in the ventricle, the structure of the second stent 120 makes the valve prosthesis more sparse on the side close to the outflow tract than the stent body of the prior art, and thus the left ventricular outflow tract obstruction can be reduced when the valve prosthesis of the present embodiment is used as a mitral valve, and the left ventricular outflow tract obstruction can be reduced when used as a main arterial valve.
Because the first leaflet retainer portion 134 of the leaflet assembly 130 for securing has a curvature, in some embodiments, the connecting end 210 is configured to have an extension curvature that matches the first leaflet retainer portion 134 such that the first leaflet retainer portion 134 fully conforms to the connecting end 210. Such a configuration, such that the leaflet assembly 130 is in contact with the stent body and distal to the first stent 110, is entirely a sparse structure formed by a plurality of stent struts, further reduces the risk of thrombus formation in this region.
In this embodiment, the number of the support rods 121 is at least 2, preferably 2-5. Too many support poles can increase the material of support main part, increase conveyor's cross-sectional area to can increase the wound area, support pole quantity is too little, can't provide sufficient stationary force for the lamella to guarantee that the lamella is smooth to open and close.
The bracket bar 121 may be located at any position of the connection end 210 of the first bracket. In some embodiments, the valve prosthesis is used to replace a locally diseased native leaflet, and the stent body is configured in a non-closed configuration, such as a fan-shaped configuration, for use with a native posterior leaflet when repairing the anterior leaflet of the mitral valve, and for use with a native anterior leaflet when repairing the posterior leaflet of the bivalve. Of course, such a structure may also be used for aortic valve or tricuspid valve repair, and the stent body and the leaflet assembly 130 are disposed according to the repair object.
With continued reference to fig. 1A, the connection end 210 of the first bracket has two ends (a and E) along the extending direction thereof, and at this time, the second bracket 120 is provided with at least two bracket bars 121, and the bracket bars 121 are preferably fixed to the ends of the connection end 210, either to one of the ends of the connection end 210 or to both ends of the connection end 210. The stent struts 121 fixed at the ends can form a relatively stable support for the leaflet assembly 130 relative to other positions. In some embodiments, when the leaflet assembly 130 is configured with multiple leaflets, the support rod 121 can also be configured between two adjacent artificial leaflets for securing the two adjacent leaflets. Wherein the junction between two adjacent leaflets is configured as a second leaflet fixing portion 135, and the leaflet assembly 130 is further fixed to the above-described stent rod 121 by the second leaflet fixing portion 135.
Referring to fig. 1B, the leaflet assembly 130 has three artificial leaflets, the leaflet 131, the leaflet 132 and the leaflet 133, and the edge of the leaflet assembly 130 is configured as the above-described first leaflet fixing portion 134, and a second leaflet fixing portion 135 is respectively configured between the leaflet 131, the leaflet 132 and between the leaflet 132 and the leaflet 133. The connecting end 210 of the first bracket 110 has a first connecting end 211, a second connecting end 212 and a third connecting end 213, and the first connecting end 211 and the third connecting end 213 are symmetrically disposed at two sides of the second connecting end 212, wherein each connecting end is used for fixedly connecting with a leaflet, and each connecting end is configured to have an extension radian matched with the fixed end of the leaflet to be fixed. Wherein, a support rod 121 is fixed at the end point a of the first connecting end 211 and the end point E of the third connecting end 213, and at the same time, a support rod 121 is configured between the first connecting end 211 and the second connecting end 212 and between the second connecting end 212 and the third connecting end 213, respectively, such that a support rod 121 is configured between two end points of the connecting end 210 and two adjacent valve leaflets, respectively. After the leaflet assembly 130 is fixed, the second leaflet fixing parts 135 are respectively fixed to one support rod 121. The support rod 121 can provide a fixed position for the valve leaflet, provide corresponding acting force for opening and closing the valve leaflet, reduce the opening amplitude of the valve leaflet, and reduce the acting force of beating tissues when the valve leaflet is opened, thereby prolonging the service life of the valve leaflet, and simultaneously can provide stable supporting function for the valve leaflet assembly 130 so as to prevent the valve leaflet from being separated from the support rod when the valve leaflet is closed.
The second stent 120 can provide a fixed location for the leaflets, alternatively, the fixed location can be located anywhere on the stent stem 121. Specifically, referring to fig. 3, in some embodiments, the support rod 121 is configured to have a first end 120-1 fixed to the first support 110, the support rod 121 further has a leaflet attachment portion 120-2 for fixing a leaflet, and a distance between the leaflet attachment portion 120-2 and an end surface of the first end 120-1 is 1/12 to 1/2 of a length of the support rod 121. Because the area of the first bracket 110 is larger, the leaflet assembly 130 is sutured at the middle and upper position of the bracket rod 121, which is beneficial for the first bracket 110 to share the acting force of the leaflet assembly 130 on the bracket rod 121.
Further, the leaflet attachment part 120-2 is configured to have a plurality of suture holes, which are diamond-shaped, circular, triangular, etc., preferably circular, and the circular small holes can uniformly disperse the force of the leaflet assembly 130 against the stent rod on the stent rod 121, thereby increasing the durability of the stent rod 121. The number of suture holes may be 1-10, preferably 2-5, and the greater the number of suture holes, the weaker the strength of the stent rod and the lesser the number of suture holes, the weaker the supporting force of the stent rod received by the leaflet assembly 130.
Further, the first end 120-1 may be configured in a column shape, such as a cylinder shape or a prism shape (e.g., a quadrangular prism), preferably, the first end 120-1 may be configured in a horn shape, as shown in fig. 3, such that the horn shape may smooth the bracket rod 121 and the first bracket 110 excessively, and may uniformly disperse the force applied to the second bracket 120 over the entire bracket body, thereby increasing the durability of the bracket body.
In some embodiments, the free end of the support rod 121 may be cylindrical, conical in shape, preferably, the free end of the support rod 121 is configured as a curved hook 120-3. The hooking portion 120-3 at the free end of the support rod 121 may hook the native valve leaflet or tissue, which may serve as a fixing support body, and at the same time, the range of motion of the native valve leaflet is limited, further reducing the risk of the native valve She Duzhu flowing out of the tract.
In some preferred embodiments, at least two of the support rods 121 of the second support 120 are provided with the hooks 120-3. The greater the number of hooks 120-3, the greater the force on the native leaflets, preventing the native leaflets from causing outflow tract obstruction during systole. Preferably, the bracket bar 121 provided with the hooking portion 120-3 should be disposed at both sides of the midpoint C of the connection end 210 of the first bracket. As shown in fig. 1, when the connecting rod 120 at the position of the connecting end a of the first bracket 110 has a hook portion, the connecting rod 120 at the position of E is correspondingly configured with a hook portion, and the hook portions are symmetrically arranged, so that the acting force of the native valve leaflet or tissue to the bracket main body is easier to balance, and the more stable the bracket is anchored.
In some embodiments, the second bracket 120 is angled at an angle γ of 10-175 °, preferably, γ is 90-160 °, with respect to the first bracket 110, as shown in fig. 4. At this angle, the first stent 110 may tightly bind with the atrium, which may provide sufficient anchoring sites for the first stent 110.
In a preferred embodiment, the second stent 120 further comprises a leaflet cutter 140 for cutting the native leaflets, such as when repairing the mitral valve, by which the larger native leaflets can be cut open, avoiding an oversized native leaflet She Duzhu out of the tract, see fig. 1A, 5. Further, the petals She Qiege are fixed to the connecting end 210 of the first support 110, and are fixed between two adjacent support rods 121, and the support rods 121 on both sides of the leaflet cutting member 140 should be configured with the hooks described above, so that after the leaflet cutting member 140 cuts the native leaflet, the support rods 121 on both sides can hook the native leaflet.
With the side of the leaflet assembly 130 being the inner side of the stent body or valve prosthesis, in some embodiments the leaflet She Qiege pieces 140 are configured to extend in a direction away from the leaflet assembly 130, see fig. 4, the leaflet She Qiege pieces 140 extend toward the outer side of the stent body, and the angle α between the leaflet cutting pieces 140 and the direction of extension of the stent rod 121 is 0-90 °, and more preferably, the angle α is 0-45 °. This design can ensure that the petals She Qiege pieces 140 have cut open the native leaflets before the stent struts 121 hook the native leaflets, so that the native leaflets can be effectively secured, preventing the oversized leaflets from occluding the outflow tract. At the same time, the angle enables the leaflet cutting member 140 to be far away from the leaflet assembly 130, so that the leaflet cutting member 140 does not interfere with the normal opening and closing of the replacement leaflet.
In some embodiments, the flap She Qiege is configured with a plurality of cutting portions 141, see fig. 6A-6D, the cutting portions 141 may be configured as triangles, squares, or the cutting portions 141 may have rounded cutting edges, and the specific form of the cutting portions 141 may be set according to actual clinical needs. Specifically, in order to prevent the cutting part 141 from damaging the delivery device or the tissue, the cutting part 141 may be constructed in a rounded structure, and further, in order to achieve a superior cutting effect, the cutting part 141 may be constructed to have a sharp cutting structure, such as a sharp cutting tip, or a knife-shaped cutting part, and in this case, the cutting part 141 may be optionally made of a degradable material, such as polylactic acid, which is degraded after cutting is completed.
In some embodiments, the plurality of cutting portions 141 are disposed in a continuous manner along the direction in which the flap She Qiege extends, and the cutting portions 141 are sequentially adjacent to each other, as shown in fig. 6B and 6C, and the cutting portions disposed in series can make cutting smoother. In some embodiments, the cutting portions 141 are disposed in a discontinuous manner, see fig. 6A and 6D, where the cutting portions 141 are disposed at intervals, and the discontinuous cutting portions can provide greater cutting force.
With continued reference to FIG. 1, flap She Qiege member 140 is secured at 1/12-11/12 of second connecting end 212, and preferably flap She Qiege member 140 is secured at midpoint C of second connecting end 212. This position allows the force of the flap She Qiege member 140 against the first bracket 110 to be evenly distributed across the left and right sides of the first bracket 110.
In one embodiment, the cutting portion 141 may be configured to be received within the leaflet cutting member 140 in an implanted state, and in use, the cutting may be accomplished by exposing the cutting portion 141 through a rotating handle operation provided.
In some embodiments, the prosthetic valve is used to replace the mitral, tricuspid or active valve entirely, in which case the stent body should be constructed as an annular closed structure. That is, the first stent 110 is constructed in a ring-shaped closed structure in the circumferential direction, the leaflet assembly 130 is fixed to the inner circumferential side of the ring-shaped stent body, and the stent rods 121 of the second stent 120 are arranged in the circumferential direction of the first stent 110. In this case, the stent body may be made of a balloon-expandable material.
Specifically, the two parts of the first bracket 110 and the second bracket 120 are fixedly connected to each other, and the connection manner includes, but is not limited to, welding, clip fixing, sewing or integrally manufacturing. Preferably, the valve is integrally prepared, so that the preparation process can be reduced, the connection strength can be enhanced, and movable supporting force can be provided for the valve leaflet. The leaflet assembly 130 is fixedly attached to the second stent 120 by means including, but not limited to, welding, clip fastening or suturing, preferably suturing. Further, to increase the biocompatibility of the second stent 120, a biocompatible material such as PET, PTFE, etc. may be coated on the outside thereof.
The valve prosthesis provided in this embodiment replaces the mesh frame structure of the middle and lower parts of the lower ventricle in the prior art due to the design of the stent rod in the second stent 120, reduces the material of the stent body, and the side of the joint of the leaflet component and the second stent is a sparse structure composed of the stent rods, so that blood is not easy to deposit at the joint, thereby reducing the risk of thrombosis. At the same time, it also helps to reduce outflow tract obstruction or obstruction.
The foregoing disclosure is only illustrative of the preferred embodiments of the invention, and not all details thereof are set forth, it being understood that the embodiments are merely illustrative of the invention, and not limiting of the scope of the invention, which is defined by the appended claims and their full scope and equivalents.
The embodiments were chosen and described in order to best explain the principles of the invention and the practical application, to thereby enable others skilled in the art to best utilize the invention. Obviously, many modifications and variations are possible in light of the above teachings, and those skilled in the art will readily recognize that there would be practical applications and variations from the present invention and that would still be within the spirit and scope of the present invention. The technical features in the different embodiments can be combined arbitrarily without mutual conflict.