Detailed Description
For the purpose of making the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is apparent that the described embodiments are some embodiments of the present invention, but not all embodiments of the present invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention. In addition, as long as there is no conflict or conflict between the embodiments described below, the same or similar concepts or processes may not be described in detail in some embodiments.
The "inflow end" and the "outflow end" of the prosthetic heart valve holder and its components, the prosthetic heart valve and its components are defined according to the direction of blood flow in the ventricular diastole state, wherein "inflow end" means an end near the blood inflow side or near the atrial side, and "outflow end" means an end near the blood outflow side or near the ventricular side.
"Axial" refers to a direction parallel to the line connecting the center of the outflow end and the center of the inflow end. "radial" refers to a direction perpendicular or substantially perpendicular to the axial direction. "circumferential" refers to a direction about the axial direction. "central axis" refers to the center line of the outflow end and the inflow end. "upper", "upper" or "top" or similar terms refer to an orientation near the inflow end. "under", "lower" or "bottom" or similar terms refer to an orientation near the outflow end. "radially outward" is the side radially away from the central axis. "radially inward" is the side radially closer to the central axis.
"Inner"/"outer" is a set of relative terms, meaning that one feature or the entirety of the component in which that feature is located is at least partially radially inward/radially outward of another feature or the entirety of the component in which that other feature is located.
"Initiation end" refers to the connection end of a feature for connection to its adjacent feature. "terminal" refers to the end of a feature opposite its initial end, and in some cases also "free end".
"Proximal" refers to the end of the device or element that is adjacent to the operator. "distal" refers to the end of the device or element that is remote from the operator.
It should be noted that the above terms indicating orientation or positional relationship are merely for convenience of description and simplification of the description, and are not intended to indicate or imply that the apparatus or elements in question must have a specific orientation, be constructed and operate in a specific orientation, and therefore should not be construed as limiting the invention.
Referring to fig. 1 to 3, a prosthetic heart valve 100 according to a first embodiment of the present invention includes a prosthetic heart valve holder 10, and at least two prosthetic leaflets 20 disposed in the prosthetic heart valve holder 10. The prosthetic heart valve stent 10 includes an inner stent 30 and an outer stent 40 that are interconnected. Preferably, the inner support 30 is coaxially arranged within the outer support 40. In other words, the central axis of the inner stent 30 described herein coincides with the central axis of the outer stent 40, all denoted herein as L.
The prosthetic heart valve stent 10 of the present invention has a delivery state after radial compression and a natural state after radial expansion. In the delivery state, the prosthetic heart valve stent 10 is radially compressed by an external force so that it can be compressed into a sheath of smaller radial dimension for delivery to the heart by the delivery device. In a natural state, the artificial heart valve stent 10 is free from the action of external force, and is radially and naturally unfolded, and the structural characteristics of the artificial heart valve stent 10 in the natural state are all described below unless otherwise specified.
The outer bracket 40 comprises an outer body section 41, an outer skirt section 42 extending from the outer body section 41 and located radially outward of the outer body section 41, wherein the outer skirt section 42 is located between an inflow end 410 and an outflow end 411 of the outer body section 41.
The inner carrier 30 comprises an inner body section 31 at least partially located within the outer carrier 40, and an inner skirt section 32 protruding radially outwardly of the inner body section 31 from an inflow end 310 of the inner body section 31, and the inner skirt section 32 also protrudes radially outwardly of an inflow end 410 of the outer body section 41, such that the inner skirt section 32 and the outer skirt section 42, and the section of the outer body section 41 located between the outer skirt section 42 and the inner skirt section 32 together form a radially outwardly opening receiving space 50.
It is noted that, as previously mentioned, "inner"/"outer" is a set of relative terms, meaning that one feature or the entirety of the component in which that feature resides is located at least partially radially inward/outward of another feature or the entirety of the component in which that other feature resides, and therefore, the aforementioned inner skirt section 32 is not meant to be located radially inward of the outer skirt section 42, but rather that the entirety of the inner leg 30 in which the inner skirt section 32 resides is located at least partially radially inward of the entirety of the outer leg 40 in which the outer skirt section 42 resides.
In this embodiment, the at least two artificial leaflets 20 are disposed in the inner body section 31 and fixedly connected to the inner body section 31 (e.g., by sewing), and edges of the at least two artificial leaflets 20 are butted with each other in the circumferential direction. The artificial valve leaflet 20 is preferably made of biological tissue materials such as bovine pericardium and porcine pericardium, or polymer materials such as ultra-high molecular weight polyethylene.
Referring to fig. 4a to 4c, the prosthetic heart valve 100 is implanted to the native valve of the heart to be replaced, for example at the mitral valve MV between the left atrium LA and the left ventricle LV, and the corresponding annulus MVA is accommodated in said accommodation space 50 of the prosthetic heart valve holder 10, thereby positioning the prosthetic heart valve 100. The at least two artificial leaflets 20 are tightly closed to prevent reflux of blood from the left ventricle LV to the left atrium LA when the left ventricle LV is in a compressed state, and the at least two artificial leaflets 20 are open to allow blood to flow from the left atrium LA into the left ventricle LV when the left ventricle LV is in an expanded state.
It is not difficult to find that the prosthetic heart valve 100 in the present embodiment accommodates the annulus MVA with the accommodation space 50 of the stent 10 thereof, the section of the outer body section 41 of the prosthetic heart valve stent 10 located between the outer skirt section 42 and the inner skirt section 32 radially supports the annulus MVA, the outer skirt section 42 is blocked by the annulus MVA to prevent the prosthetic heart valve stent 10 from shifting toward the heart chamber side, the inner skirt section 32 is blocked by the annulus MVA to prevent the prosthetic heart valve stent 10 from shifting toward the heart chamber side, thereby achieving positioning of the prosthetic heart valve 100 without penetrating the annulus MVA with barbs to achieve positioning of the prosthetic heart valve stent as in the prior art, and thus damage to the annulus MVA can be reduced.
It will be appreciated that the prosthetic heart valve 100 may be implanted in the heart using minimally invasive interventional procedures. For example, the radially compressed prosthetic heart valve 100 may be received by a delivery device (described in more detail below) and the prosthetic heart valve 100 may then be delivered to the vicinity of the mitral valve and released to replace the diseased native valve via the apex, transaxial, or transfemoral-superior vena cava-right atrium-atrial septum-left atrium approach.
Alternatively, the prosthetic heart valve 100 can be directly implanted into the heart by other means, such as surgery, to replace the diseased native valve.
It will also be appreciated that the use of the prosthetic heart valve 100 for replacing a diseased native mitral valve, as shown in fig. 4a-4 c, is shown by way of example only. In other embodiments, the prosthetic heart valve 100 can also be used to replace other suitable native valves, such as the tricuspid valve.
Referring to fig. 3, 5 and 6, in the present embodiment, the inner body section 31 of the inner bracket 30 has a substantially hollow cylindrical shape with two ends open. Preferably, the outer diameter of the inner body section 31 ranges from 25mm to 30mm. It is also preferred that the inner body section 31 is covered with a flow blocking film 311. The material of the choke film 311 is preferably PET, PTFE, or the like.
In this embodiment, the inner body section 31 includes an inner mesh structure 33 formed by a plurality of struts 312 connected in a staggered manner. The inner mesh structure 33 is formed by axially arranging multiple layers of inner ring-shaped units 330 (for example, two layers of inner ring-shaped units 330a,330b shown in fig. 6), each inner ring-shaped unit 330 is formed by circumferentially arranging multiple cells 331, wherein each cell 331 is surrounded by multiple struts 312 and has an opening 332. Preferably, each inner annular unit 330 is formed by arranging a plurality of diamond-shaped cells 331 along the circumferential direction, wherein a plurality of struts 312 of the upper inner annular unit 330A near the inflow end 310 of the inner main body section 31 form a plurality of circumferentially alternating peaks 314A and valleys 314B, and a plurality of struts 312 of the lower inner annular unit 330B near the outflow end 313 of the inner main body section 31 form a plurality of circumferentially alternating peaks 315A and valleys 315B.
In this embodiment, the inner body section 31 further includes an inner connecting structure 35 provided at an outflow end of the inner mesh structure 33 for connecting the outer bracket 40 (corresponding connecting structure of the outer bracket 40 will be described later). In this embodiment, the internal connection structure 35 includes a plurality of internal connection units 350 arranged at intervals along the circumferential direction. Each trough portion 315B of the outflow end of the inner mesh structure 33 is correspondingly connected to an inner connecting unit 350. In this embodiment, each of the connecting units 350 has a substantially rod shape, extends axially downward from a corresponding trough portion 315B of the outflow end of the inner mesh structure 33, and is enlarged at its distal end so as to form an inner connecting hole 351 extending radially therethrough.
In this embodiment, the inner skirt section 32 of the inner leg 30 is generally flared. The inner skirt section 32 is covered with a flow blocking membrane 320 to seal against perivalvular leakage on the atrial side. The material of the choke film 320 is preferably PET, PTFE, or the like. Preferably, the inner skirt section 32 extends outwardly from the inflow end 310 of the inner body section 31 away from the central axis L of the inner bracket 30 and also extends axially away from the inflow end 310 of the inner body section 31. The inner skirt section 32 extends generally obliquely upwardly and outwardly as viewed in fig. 6.
Preferably, the initial end 321 of the inner skirt section 32 (i.e. the end near the inner body section 31, which is also the connecting end) or the tangent line of the initial end 321 of the inner skirt section 32 is in the range of 45 ° to 90 ° with respect to the central axis L of the inner frame 30, which allows the inner skirt section 32 to better adapt to the structure of the annulus MVA, reducing the likelihood of paravalvular leakage. Preferably, the tip 322 of the inner skirt section 32 (i.e., the end distal from the inner body section 31, and also the free end) is inclined at an angle A2 with respect to the central axis L of the inner stent 30 that is smaller than the angle A1 of the initial end 321 of the inner skirt section 32 with respect to the central axis L of the inner stent 30, so that the inner skirt section 32 better fits the annulus MVA, further improving the positioning stability of the prosthetic heart valve stent 10 and reducing the likelihood of paravalvular leakage.
Preferably, the diameter D1 of the distal end 322 of the inner skirt section 32 ranges from 40mm to 70mm, which is about 10mm larger than the inner diameter of a conventional native annulus MVA, effectively preventing the prosthetic heart valve 100 from shifting to the ventricular side and reducing the likelihood of paravalvular leakage.
Optionally, the inner skirt section 32 of the inner leg 30 comprises a plurality of circumferentially distributed inner skirt units 323. Each inner skirt unit 323 includes two struts 324, wherein the initial ends 321 of the two struts 324 are respectively connected directly or indirectly to a corresponding peak 314A of the inflow end of the inner mesh structure 33, and the distal ends 322 of the two struts 324 are connected. The angle A3 between the struts 324 of each inner skirt unit 323 is preferably in the range of 30 ° to 150 °. Preferably, the two struts 324 of each inner skirt unit 323 are connected directly or indirectly with the two adjacent peaks 314A of the inflow end of the inner mesh structure 33. More preferably, two adjacent struts 324 of two adjacent inner skirt units 323 of the inner skirt section 32 intersect, i.e. correspond to the same crest 314A of the inflow end of the inner mesh structure 33. The angle A4 between two adjacent struts 324 of two adjacent inner skirt units 323 preferably ranges from 30 ° to 150 °. It can be seen that the peaks 314A of the inflow end of the inner mesh structure 33 are each directly or indirectly connected to a corresponding strut 324 of the inner skirt section 32. It will be appreciated that in other embodiments, the inner skirt section 32 may take other configurations as long as it is capable of bearing on the atrial side of the annulus MVA.
Preferably, the inner bracket 30 further comprises a connecting section 36 for connecting the inner skirt section 32 and the inner body section 31. The connecting section 36 is preferably covered with a flow blocking film 360. The material of the choke film 360 is preferably PET, PTFE, or the like. In this embodiment, the connecting section 36 includes a plurality of connecting rods 361 that are circumferentially spaced apart. One end of the connecting rod 361 is connected to the intersection of two adjacent inner skirt units 323 of the inner skirt section 32, and the other end is connected to a corresponding crest portion 314A of the inflow end of the inner mesh structure 33 of the inner body section 31. Preferably, the connecting rod 361 transitions in an arc from a corresponding crest 314A of the inflow end of the inner mesh structure 33 to the intersection of the corresponding two adjacent inner skirt units 323 to avoid breakage of the connecting rod 361.
Alternatively, the inner skirt section 32, the inner body section 31, and the connecting section 36 may be separately formed, and then the inner skirt section 32 and the inner body section 31 may be connected by the connecting section 36 (e.g., by crimping, riveting, welding, or sewing).
Preferably, the inner skirt section 32, the inner body section 31, and the connecting section 36 are integrally formed. In other words, the inner bracket 30 is preferably a single piece.
Alternatively, the inner stent 30 or each portion of the inner stent 30 is formed into a desired shape by laser cutting a tube having a shape memory function such as a nickel titanium tube and performing a heat setting process. Or the inner stent 30 or each part of the inner stent 30 may be formed into a desired shape by braiding a wire material having a shape memory function such as a nitinol wire and performing a heat setting treatment.
Referring to fig. 3, 5 and 7, in this embodiment, the inflow end 410 of the outer body section 41 of the outer stent 40 is free to hang, and there is a radial gap 60 between the section of the outer body section 41 between the outer skirt section 42 and the inner skirt section 32 (which section supports the annulus tissue in the radial direction, which may be referred to as a support section) and the inner body section 31. The radial distance L1 of the radial gap 60 preferably ranges from 1mm to 18mm, more preferably from 5mm to 18mm. The radial gap 60 is designed such that the support section on the outer stent 40 is radially spaced from the inner body section 31 of the inner stent 30, and when the outer stent 40 of the prosthetic heart valve 100 which has been implanted in the heart is deformed inward by radial extrusion of the annulus MVA, the radial gap 60 provides sufficient deformation space for the support section on the outer stent 20, so that the radial extrusion deformation of the outer stent 40 by the annulus does not affect the inner skirt section 32 of the inner stent 30, avoiding the gap between the inner skirt section 32 and the atrial side of the annulus due to the deformation of the outer stent 40, and the inner skirt section 32 is covered with the flow blocking film 320, which can effectively isolate the atrium from the ventricle, ensure the tightness of the atrial side, and reduce the risk of paravalvular leakage.
In this embodiment, the outer body section 41 of the outer bracket 40 includes an outer net structure 44 formed by a plurality of struts 412 connected in a staggered manner. The outer web-like structure 44 includes a bottom section 45 extending outwardly away from the central axis L of the outer hanger 40 and also extending toward the inner skirt section 32, and a top section 46 extending from the inflow end of the bottom section 45 further toward the inner skirt section 32.
In this embodiment, the bottom section 45 is generally funnel-shaped, tapering from its inflow end 450 toward its outflow end 451 toward the central axis L of the outer support 40. The greater the angle of collapse, i.e., the greater the degree of inclination toward the central axis L of the outer bracket 40, the shorter the axial length of the bottom section 45, and conversely, the lesser the angle of collapse, i.e., the lesser the degree of inclination toward the central axis L of the outer bracket 40, the longer the axial length of the bottom section 45. In order to reduce the overall height of the outer support 40, the angle A5 formed by the diametrically opposite tangents to the outflow end 451 of the bottom section 45 is preferably in the range of 90 ° to 150 °.
Referring to fig. 3, 5, 7 and 8a, in this embodiment, the top section 46 is generally in the shape of a hollow cylinder with two ends open, and the shape of its circumferential outer contour is in the shape of an "O", which helps to simplify the manufacturing process of the outer bracket 40. In other words, the top section 46 in this embodiment is generally uniform in diameter throughout. Preferably, the diameter D2 of the top section 46 ranges from 30mm to 60mm, which is comparable to the inner diameter of the native annulus MVA, helping the annulus MVA to stably radially compress the top section 46.
Referring to fig. 8b, in other embodiments, the circumferential outer contour of the top section 146 may also take other shapes, such as a "D" shape, which helps the top section 146 better accommodate the structure of the native annulus MVA, avoiding stressing the ventricular outflow tract.
Referring again to fig. 3, 5 and 7, in the present embodiment, the outer net-like structure 44 of the outer body section 41 is formed by axially arranging a plurality of outer ring-like units 440, each outer ring-like unit 440 is formed by circumferentially arranging a plurality of cells 441, wherein each cell 441 is surrounded by a plurality of struts 412 and has an opening 442.
Preferably, the outer mesh structure 44 of the outer body section 41 has a lower resistance to deformation than the inner mesh structure 33 of the inner body section 31 so that the outer stent 40 can better accommodate the native annulus MVA while also making the inner stent 30 sufficiently resistant to the pulling force of the prosthetic leaflet 20. By deformation resistance is meant the ability to deform against external stress, the higher the deformation resistance, the smaller the amplitude of deformation and vice versa under the same stress. This may be accomplished, for example, by making the area of the openings 442 of the cells 441 of the outer mesh structure 44 larger than the area of the openings 332 of the cells 331 of the inner mesh structure 33. It will be appreciated that in other embodiments, the deformation resistance of the inner body section 31 may be higher than that of the outer body section 41, for example, by selecting materials of different hardness, different strut sizes, etc., it being understood that the greater the hardness of the material, the greater the deformation resistance, and the greater the strut size.
In this embodiment, the outer net-like structure 44 is formed by staggering two outer ring-like units 440 such that one cell 441 of each outer ring-like unit 440 is adjacent to two adjacent cells 441 of another adjacent outer ring-like unit 440. Preferably, the area of the openings 442A of the cells 441A that are primarily used to form the upper outer annular cells 440A of the top section 46 is greater than the area of the openings 442B of the cells 441B that are primarily used to form the lower outer annular cells 440B of the bottom section 45, such that the deformation resistance of the top section 46 is lower than the deformation resistance of the bottom section 45. This not only increases the flexibility of the top section 46, thereby enhancing the adaptation of the top section 46 to the annulus MVA, but also makes the bottom section 45 less deformable to retain its shape. It will be appreciated that in other embodiments, the resistance to deformation of the top section 46 may be lower than the resistance to deformation of the bottom section 45, such as by selecting materials of different hardness, different strut sizes, etc., it being understood that the higher the hardness of the material, the higher the resistance to deformation of the strut.
In this embodiment, each of the outer ring units 440 is formed by arranging a plurality of diamond-shaped cells 441 along the circumferential direction, that is, each of the outer ring units 440 is formed by axially connecting two layers of corrugated rods 443, wherein each layer of corrugated rods 443 is formed by connecting a plurality of struts 412 end to end along the circumferential direction, and has a plurality of peak portions 444A and trough portions 444B alternately distributed along the circumferential direction. The two layers of the outer ring-shaped units 440a,440B share the middle-layer corrugated bar 443B.
Preferably, the struts 412 of the three-layer corrugated struts 443 of the outer mesh structure 44 have a width (i.e., the distance between the radially inner side or the radially outer side of the struts 412) that gradually increases from the inflow end of the outer mesh structure 44 to the outflow end of the outer mesh structure 44, which helps to further increase the compliance of the top section 46, thereby further increasing the compliance of the top section 46 to the annulus MVA. More preferably, all struts 412 of the outer netting 44 have a width of no more than 0.5mm. Optimally, the widths of the struts 412 of the upper, middle and lower corrugated bars 443A, 443B, 443C of the outer mesh-like structure 44 are 0.3mm, 0.4mm, 0.5mm, respectively.
In this embodiment, the outer body section 41 of the outer bracket 40 further includes an outer connecting structure 47 provided at the outflow end of the outer net structure 44 for connecting the inner connecting structure 35 of the inner bracket 30. The outer connection structure 47 includes a plurality of outer connection units 470 arranged at intervals in the circumferential direction. Preferably, each trough 444B of the outflow end of the outer net structure 44 is correspondingly connected to an outer connection unit 470. In this embodiment, each outer connecting unit 470 is generally rod-shaped, extends axially downwardly from a corresponding trough 444B at the outflow end of the outer web-like structure 44, and is enlarged at its distal end to form an outer connecting hole 471 extending radially therethrough.
When the outer and inner brackets 40 and 30 are coupled, the inner bracket 30 may be placed in the outer bracket 40 such that the outer coupling holes 471 are aligned with the corresponding inner coupling holes 351, and then the outer and inner coupling holes 471 and 351 are inserted with a coupling member such as a coupling pin, thereby coupling the outer and inner brackets 40 and 30. It will be appreciated that in other embodiments, other means, such as stitching, may be used to connect the outer and inner stents 40, 30.
In this embodiment, the outer bracket 40 further includes a limiting structure 43 disposed at an end of the outer connecting structure 47 for connection with a conveying device (described in detail below). Optionally, the limiting structure 43 includes at least one limiting rod 430 disposed at an end of the outer connection unit 470. Referring to fig. 9a, in the present embodiment, the stopper rod 430 has a substantially T-shape, and includes a rod portion 431 for connecting with the external connection unit 470, and an engaging portion 432 enlarged from the end of the rod portion 431. In this embodiment, the axial section of the engaging portion 432 of the stop lever 430 is substantially circular. It is understood that in other embodiments, the engaging portion may take other shapes. For example, as shown in fig. 9B, in some embodiments, the axial cross-section of the engaging portion 432B may be rectangular. In some embodiments, as shown in fig. 9C, the axial cross-section of the engaging portion 432C may be semicircular.
Referring again to fig. 3, 5 and 7, in this embodiment, the outer skirt section 42 of the outer bracket 40 extends outwardly from a generally central location of the outer body section 41 of the outer bracket 40 toward the central axis L of the outer bracket 40 while also extending toward the inner skirt section 32. The outer skirt section 42 extends generally obliquely upwardly and outwardly as viewed in fig. 7. Preferably, the outer skirt section 42 extends outwardly from the intersection of the top section 46 and the bottom section 45. In other words, the outer skirt section 42 extends outwardly from the outer body section 41 at the location having the largest diameter, and the support section of the outer body section 41 between the outer skirt section 42 and the inner skirt section 32 for forming the accommodation space 50 is the top section 46.
It will be appreciated that in other embodiments, the outer skirt section 42 may extend outwardly from other portions of the outer body section 41, such as from a portion of the top section 46 adjacent the outflow end thereof. In this case, a partial section of the top section 46 is configured as a support section for forming the accommodation space.
Preferably, the minimum axial distance H between the inner skirt section 32 and the outer skirt section 42 is in the range of 5mm to 15mm, which is approximately equivalent to the thickness of the native annulus MVA, so that the annulus MVA is stably held after being accommodated in the accommodating space 50 without a large gap to cause the prosthetic heart valve holder 10 to shake, and the positioning effect is better.
Preferably, the initial end 421 of the outer skirt section 42 (i.e. the end near the outer body section 41, also the connecting end) or the angle A6 between the tangent of the initial end 421 of the outer skirt section 42 and the central axis L of the outer bracket 40 is in the range of 60 ° to 120 °. The end 422 of the outer skirt section 42 (i.e. the end remote from the outer body section 41, also the free end) or the angle A7 between the tangent to the end 422 of the outer skirt section 42 and the central axis L of the outer bracket 40 is in the range 60 ° to 120 °.
More preferably, the outer skirt section 42 extends outwardly in an arc shape relative to the outer body section 41, and the angle A8 between the tangent line at the substantially middle portion thereof and the central axis L of the outer bracket 40 ranges from 30 ° to 90 °, which facilitates the radial outward expansion of the outer skirt section 42, with a space between the initial end 421 and the terminal end 422 for making an arc transition.
Also preferably, the maximum outer diameter of the outer skirt section 42, in this embodiment the diameter D3 of the distal end 422 of the outer skirt section 42, ranges from 40mm to 70mm, which is about 10mm larger than the inner diameter of a conventional native annulus MVA, effectively prevents the prosthetic heart valve 100 from being displaced toward the atrial side.
Referring to fig. 7 and 10a, in this embodiment, the outer skirt section 42 includes a plurality of support units 423 uniformly and intermittently distributed in the circumferential direction. Each support unit 423 includes two support bars 424. Each support bar 424 includes a first end 425 remote from the outer body section 41 and connected to another support bar 424, and a second end 426 connected to the outer body section 41. In this embodiment, the second end 426 of each support rod 424 is connected to a substantially middle portion of a corresponding strut 412 of the middle corrugated rod 443B. The first ends 425 of the two support rods 424 of each support unit 423 are connected, preferably forming blunt ends, e.g. circular arcs, to reduce irritation and damage to the native annulus MVA. The second ends 426 of two adjacent support rods 424 of two adjacent support units 423 are spaced apart. Preferably, two adjacent support bars 424 of two adjacent support units 423 are spaced apart by one cell 441. It will be appreciated that in other embodiments, the outer skirt section 42 may take other configurations as long as it supports the ventricular side of the annulus MVA.
For example, as shown in fig. 10B, in other embodiments, the two support rods 424B of the support unit 423B may extend arcuately from the first end 425B thereof in a direction away from the symmetry axis of the support unit 423B (i.e., the axis between the two support rods 424B), which may increase the relative support area for the native annulus MVA. In other embodiments, as shown in fig. 10C, each support rod 424C of the support unit 423C may extend from its first end 425C in a direction away from the axis of symmetry of the support unit 423C. In other embodiments, as shown in fig. 10D, each support rod 424D of the support unit 423D may extend linearly from its first end 425D in a direction away from the axis of symmetry of the support unit 423D.
For another example, as shown in FIG. 11a, in other embodiments, each of the support units 423E of the outer skirt section may no longer include two support bars 424. Instead, each supporting unit 423E may have a substantially rod shape. Preferably, the end of each rod-shaped supporting unit 423E is formed as a blunt end extending outwardly in an arc shape with respect to the outer body section 41. Preferably, each supporting unit 423 extends outwardly from a corresponding valley 444B of the middle corrugated bar 443B or a corresponding peak 444A of the lower corrugated bar 443C.
As another example, as shown in fig. 11b, in other embodiments, the end of each rod-shaped supporting unit 423F may be formed as a rounded blunt end. In other embodiments, as shown in fig. 11C, the end of each rod-shaped supporting element 423G may be formed as a blunt end in a general "C" shape. In other embodiments, as shown in fig. 11d, the end of each rod-shaped supporting unit 423H may be formed as a rectangular blunt end.
Alternatively, the outer skirt section 42, and the outer body section 41 are separately formed, and the outer skirt section 42 is then connected (e.g., by crimping, riveting, welding, stitching, or the like) to the outer body section 41.
Preferably, the outer skirt section 42, and the outer body section 41 are integrally formed. In other words, the outer support 40 is preferably a single piece.
Alternatively, the outer stent 40 or each portion of the outer stent 40 is formed into a desired shape by laser cutting a tube having a shape memory function such as a nickel titanium tube and performing a heat setting process. Or the outer stent 40 or each part of the outer stent 40 may be formed into a desired shape by braiding a wire material having a shape memory function such as nitinol wire and performing a heat setting process.
Referring to fig. 12, the prosthetic heart valve of the second embodiment of the present invention is similar to the prosthetic heart valve 100 of the first embodiment, and the details thereof are not repeated here. The main difference between the prosthetic heart valve of the second embodiment of the present invention and the prosthetic heart valve 100 of the first embodiment is that the outer stent 140 of the prosthetic heart valve of the second embodiment of the present invention is further provided with a developing mechanism 48 to determine the actual position of the prosthetic heart valve when the prosthetic heart valve is implanted in vivo, especially when the prosthetic heart valve is implanted by a minimally invasive intervention operation. The material of the developing mechanism 48 may be a developing material of tungsten, gold, platinum, tantalum, or the like that is visible under X-rays.
As shown in conjunction with fig. 12 and 13a, the visualization mechanism 48 of the prosthetic heart valve of the present embodiment includes a plurality of visualization points 480. The developing point 480 may be fixed to the inflow end of the outer bracket 140 by, for example, crimping or the like. Preferably, the plurality of developing points 480 are uniformly and intermittently distributed at the plurality of peak portions 444A of the inflow end of the top section 46 of the outer frame 140. It will be appreciated that in other embodiments, multiple visualization points may be provided at other locations of the prosthetic heart valve stent. For example, a plurality of developing points 480 may also be provided on the inner skirt section 32 of the inner carrier 30. Or only one developing point 480 may be provided.
In other embodiments, the developing mechanism may take other configurations. For example, as shown in fig. 13B, in other embodiments, the developing mechanism may include a plurality of developing sections 480B, each developing section 480B may be formed from a respective peak 444A of a length of developing wire/thread secured to the inflow end of the top section 46, such as by winding. For another example, as shown in fig. 13C, in other embodiments, the developing mechanism may be configured as a continuous, complete developing ring 480C, and the developing ring 480C may be formed from a length of developing wire/thread threaded through the plurality of peaks 444A of the inflow end of the top section 46 and secured to the inflow end of the top section 46, such as by stitching. It will be appreciated that in other embodiments, the developing mechanism may be formed in a continuous, but incomplete, configuration, such as an arcuate, semi-circular configuration.
Referring to fig. 14a, the prosthetic heart valve of the third embodiment of the present invention is similar to the prosthetic heart valve 100 of the first embodiment, and the details thereof are not repeated here. The main difference between the prosthetic heart valve according to the third embodiment of the present invention and the prosthetic heart valve 100 according to the first embodiment of the present invention is that the outer skirt section 42 of the prosthetic heart valve according to the third embodiment of the present invention is covered with the protective film 427 to further reduce the irritation of the outer skirt section 42 to the annulus MVA and prevent the outer skirt section 42 from damaging the annulus MVA. The material of the protective film 427 is preferably PET, PTFE, or the like. As can be seen from the figure, the protective film 427 in this embodiment is formed as a continuous ring. That is, the protective film 427 in this embodiment covers not only all the supporting units 423 but also the gaps between the adjacent supporting units 423.
It will be appreciated that in other embodiments, the protective film may take other configurations. For example, as shown in fig. 14B, in other embodiments, the protective film 427B may include a plurality of circumferentially spaced segments, each of which covers a corresponding support element 423, and also prevents damage to the annulus MVA from the outer skirt segment 42.
Referring to fig. 15 and 16, the prosthetic heart valve according to the fourth embodiment of the present invention is similar to the prosthetic heart valve 100 according to the first embodiment, and the details thereof are not repeated here. The main difference between the prosthetic heart valve of the fourth embodiment of the present invention and the prosthetic heart valve 100 of the first embodiment is that the outer skirt section 342 of the prosthetic heart valve of the fourth embodiment of the present invention is configured as a continuous ring. In other words, in this embodiment, the first ends 3425 of the two support rods 3424 of each support unit 3423 are connected, and the second ends 3426 of the two support rods 3424 of the two adjacent support units 3423 are also connected. In particular, the first ends 3425 of the two support rods 3424 of each support unit 3423 extend outwards to the radially outer side of the outer body section 41 and are connected, preferably forming a blunt end, for example in the shape of a circular arc, to reduce irritation to the native annulus MVA. The second ends 3426 of the two support rods 3424 of each support unit 3423 extend inwardly to the radially inner side of the outer body section 41 and are connected to the second ends 3426 of an adjacent support rod 3424 of an adjacent support unit 3423, again preferably forming blunt ends, for example circular arcs.
Preferably, the outer skirt section 342 in this embodiment is formed separately from the outer body section 41 and then the outer skirt section 342 is attached to the outer body section 41, such as by stitching. More preferably, the outer skirt section 342 is formed into a desired shape by braiding nickel titanium alloy wire and heat setting. The outer body section 41 is formed into a desired shape by laser cutting a nickel titanium tube and heat setting.
Referring to fig. 17 to 19, a prosthetic heart valve 500 according to a fifth embodiment of the present invention is similar to the prosthetic heart valve 100 according to the first embodiment, and the details thereof are not repeated here. The main difference between the prosthetic heart valve 500 of the fifth embodiment of the present invention and the prosthetic heart valve 100 of the first embodiment is that the outer body section 41 of the outer stent of the prosthetic heart valve 500 of the fifth embodiment of the present invention is also covered with a flow blocking film 413. The material of the choke film 413 is preferably PET, PTFE, or the like. The sealing of the atrial side of the annulus MVA by the flow blocking membrane 320 of the inner skirt section 32 and the sealing of the ventricular side of the annulus MVA by the flow blocking membrane 413 of the outer body section 41 achieves a double-layer seal, thereby further enhancing the sealing effect of the prosthetic heart valve 500 and reducing the likelihood of paravalvular leakage.
Referring to fig. 20 to 22, the prosthetic heart valve according to the sixth embodiment of the present invention is similar to the prosthetic heart valve 100 according to the first embodiment, and the details thereof are not repeated here. The main difference between the prosthetic heart valve of embodiment six and the prosthetic heart valve 100 of embodiment one is that the top section 546 of the outer stent 540 of the prosthetic heart valve of embodiment six is no longer uniform in diameter throughout. In contrast, the top section 546 of the outer bracket 540 in this embodiment extends axially toward the inner skirt section 32 while also extending inwardly toward the central axis L of the outer bracket 540. In other words, the top section 546 of the outer bracket 540 in this embodiment has a diameter gradually decreasing from its outflow end to its inflow end, thereby forming a structure gradually converging toward the central axis L of the outer bracket 540. This helps to further increase the adaptation of the outer stent 540 to the annulus MVA so that the outer stent 540 does not need to deform the top section 546 of the outer stent 540 or only need to deform the top section 546 of the outer stent 540 slightly to accommodate the annulus MVA when implanting a prosthetic heart valve.
Preferably, the radial distance L2 between the outflow and inflow ends of the top section 546 is less than the radial distance L3 between the outflow end of the top section 546 and the inner body section 31, which maintains a radial gap 560 between the top section 546 and the inner body section 31 to prevent deformation of the inner stent 30 of the implanted prosthetic heart valve 100 by the outer stent 540, thereby further reducing the likelihood of paravalvular leakage.
Referring to fig. 23 to 25, the prosthetic heart valve according to the seventh embodiment of the present invention is similar to the prosthetic heart valve 100 according to the first embodiment, and the details thereof are not repeated here. The main difference between the prosthetic heart valve of embodiment seven of the present invention and the prosthetic heart valve 100 of embodiment one is that the diameters of the top section 646 of the outer frame 640 of the prosthetic heart valve of embodiment seven of the present invention are no longer uniform. In contrast, the top section 646 of the outer bracket 640 in this embodiment extends axially toward the inner skirt section 32 while extending inwardly toward the central axis L of the outer bracket 640 and then outwardly away from the central axis L of the outer bracket 640 to form a circumferential recess 647. That is, the axial cross-section of the top section 646 in this embodiment is generally "S" shaped. The depressions 647 facilitate better fit of the annulus MVA to the top section 646, improving the adaptability of the top section 646 to the annulus MVA, thereby improving the positioning stability of the prosthetic heart valve.
Referring to fig. 26, a prosthetic heart valve replacement system in accordance with an embodiment of the present invention includes a prosthetic heart valve 11 and a delivery device 12 for delivering the prosthetic heart valve 11. The prosthetic heart valve 11 may be any of the prosthetic heart valves of the previous embodiments. The prosthetic heart valve 11 has a radially compressed delivery state and a radially expanded natural state, wherein fig. 26 schematically illustrates the delivery state of the prosthetic heart valve 11, and reference is made to the illustration of the prosthetic heart valve of any of the previous embodiments for the natural state of the prosthetic heart valve 11.
The delivery device 12 includes an outer sheath 120 and an inner core 121 penetrating the outer sheath 120, and the inner core 121 and the outer sheath 120 can move relative to each other in the axial direction. The prosthetic heart valve 11 is radially compressed and then received in a delivery state in a gap between a distal end portion of the inner core 121 and a distal end portion of the outer sheath 120. Preferably, the distal end portion of the inner core 121 is provided with a stop slot 122 for receiving the stop bar 430 of the prosthetic heart valve 11, the stop slot 122 having a shape complementary to the shape of the stop bar 430 as previously described.
During the operation, when the operator pulls the outer sheath 120 toward the proximal end or pushes the inner core 121 toward the distal end to initially release the prosthetic heart valve 11, the limiting rod 430 of the prosthetic heart valve 11 is tightly engaged with the limiting groove 122 of the inner core 121 under the restraint of the outer sheath 120, so that the prosthetic heart valve 11 can be effectively prevented from instantaneously falling off from the inner core 121, thereby facilitating the operator to observe and adjust the position of the prosthetic heart valve 11 through medical images. When the prosthetic heart valve 11 is displaced to the desired release position, the outer sheath 120 is pulled further proximally or the inner core 121 is pushed distally so that the outer sheath 120 no longer constrains the stop lever 430, and the stop lever 430 is released from the stop catch 122 under the radial expansion of the prosthetic heart valve stent itself, thereby completely releasing the prosthetic heart valve 11.
It should be noted that the above embodiments are merely for illustrating the technical solution of the present invention and not for limiting the same, and although the present invention has been described in detail with reference to the above embodiments, it should be understood by those skilled in the art that the technical solution described in the above embodiments may be modified or some or all of the technical features may be equivalently replaced, and these modifications or substitutions do not make the essence of the corresponding technical solution deviate from the scope of the technical solution of the embodiments of the present invention.