Disclosure of Invention
The invention aims to provide a valve support and a valve prosthesis, which are used for solving the problem that the existing valve support is used for extruding valve leaves so that the valve leaves block coronary passages.
In order to solve the technical problems, the invention provides a valve stent, which is in a net shape, a plurality of grid units are arranged at the far end of the valve stent along the circumferential direction, the grid units comprise four layers of structures which are sequentially connected along the axial direction, wherein,
The first layer comprises four first wave rod units which are connected in sequence;
The second layer comprises four second wave rod units which are sequentially connected, and the four first wave rod units are respectively arranged opposite to and connected with the four second wave rod units;
the third layer comprises two unconnected third wave rod units, wherein one third wave rod unit is respectively connected with two adjacent second wave rod units, and the other third wave rod unit is respectively connected with the other two adjacent second wave rod units;
The fourth layer comprises a fourth wave rod unit, and one fourth wave rod unit is respectively connected with the two third wave rod units.
Optionally, in the valve stent, a plurality of the grid cells are continuously distributed along the circumferential direction, the first layers of two adjacent grid cells are directly connected, and the fourth layers of two adjacent grid cells are connected through another fourth wave rod cell.
Optionally, in the valve stent, the number N of the grid cells is 3.ltoreq.N.ltoreq.6.
Optionally, in the valve stent described above, a plurality of the grid cells are discontinuously distributed in the circumferential direction.
Optionally, in the valve stent, the shape of the first wave rod unit is V-shaped, and the shape of the second wave rod unit, the third wave rod unit, and the fourth wave rod unit is inverted V-shaped.
Optionally, in the valve stent, the fourth wave rod unit is connected to the third wave rod unit through an axial straight rod.
Optionally, in the valve stent described above, the number of axial straight bars is greater than or equal to 3.
Alternatively, in the valve stent, the total number of layers of the valve stent is 4 or 5.
Optionally, in the valve stent, when the total number of layers of the valve stent is 4, the two-layer waver rod unit group at the distal end of the valve stent is a coronary section, and the two-layer waver rod unit group at the proximal end is an anchoring section;
When the total layer number of the valve stent is 5, the two-layer wave rod unit group at the far end of the valve stent is a coronary section, and the three-layer wave rod unit group at the near end is an anchoring section.
Optionally, in the valve stent described above, the anchoring section at the proximal end of the valve stent includes a plurality of wave rod unit groups, each wave rod unit group includes circumferentially connected wave rod units, the number and the size of the wave rod units in each wave rod unit group are the same, and two adjacent wave rod unit groups form a layer of circumferentially continuous grid.
Based on the same inventive concept, the present invention also provides a valve prosthesis comprising a valve leaflet and a valve stent as described above, the valve leaflet being fixed to the valve stent.
Compared with the prior art, the valve stent and the valve prosthesis provided by the invention have the following beneficial effects:
The valve stent is in a net pipe shape, a plurality of grid units are arranged at the far end along the circumferential direction, so that a plurality of gradual change big grids are formed at a coronary region, when the valve stent is implanted into an aortic valve annulus, the formed gradual change big grids can not extrude native valve leaflets in the radial direction at the coronary region due to larger area, so that coronary blood flow is not influenced, even if the coronary blood flow is not influenced by the coronary blood flow, a patient with poor coronary conditions (the height of the native valve leaflets is larger than that of the coronary orifice) can also provide a radial space of the valve leaflets, the valve leaflets are not extruded on the inner wall of the sinus so as to influence the coronary blood flow, therefore, the risk that the native valve leaflets block the coronary orifice is reduced, meanwhile, the grid density of the coronary region is sparse, the radial rigidity of the valve stent is lower due to the sparse grid, and the valve stent can share a part of traction deformation under the action of the valve She Qian, so that the service life of the valve leaflets is prolonged;
The valve prosthesis of the invention has all the advantages of the valve stent as well, because of the valve stent.
Detailed Description
The valve stent and the valve prosthesis according to the present invention will be described in further detail with reference to the accompanying drawings and detailed description. The advantages and features of the present invention will become more apparent from the following description. It should be noted that the drawings are in a very simplified form and are all to a non-precise scale, merely for the purpose of facilitating and clearly aiding in the description of embodiments of the invention. For a better understanding of the invention with objects, features and advantages, refer to the drawings. It should be understood that the structures, proportions, sizes, etc. shown in the drawings are for illustration purposes only and should not be construed as limiting the invention to the extent that any modifications, changes in the proportions, or adjustments of the sizes of structures, proportions, or otherwise, used in the practice of the invention, are included in the spirit and scope of the invention which is otherwise, without departing from the spirit or essential characteristics thereof.
In this context, "proximal", "lower" or "lower" and "distal", "upper" or "upper" are in reference to the direction of flow of heart blood through the valve holder, and "proximal", "lower" or "lower" and "distal", "upper" or "upper" are not limiting, but "proximal", "lower" or "lower" generally refer to the end proximal to the flow of blood into the valve holder, and "distal", "upper" or "upper" generally refer to the end proximal to the flow of blood out of the valve holder.
The core idea of the invention is to provide a valve stent and a valve prosthesis so as to solve the problem that the existing valve stent presses valve leaflets when in use, so that the valve leaflets block coronary passages.
The valve stent provided by the invention is in a net tubular shape and comprises an anchoring section and a coronary artery section, wherein the anchoring section is positioned at an inflow end (namely a proximal end) of a valve, the coronary artery section is positioned at an outflow end (namely a distal end) of the valve, the inflow end corresponds to the inflow direction of blood flow, the outflow end corresponds to the outflow direction of blood flow, and the direction from the inflow end to the outflow end is the axial direction of the valve stent.
Specifically, a plurality of grid cells are arranged at the distal end of the valve stent along the circumferential direction, fig. 1 schematically shows a structural schematic diagram of the grid cells, and as shown in fig. 1, the grid cells comprise four layers of structures I-IV sequentially connected along the axial direction, wherein,
The first layer I comprises four first wave pole units 10 which are connected in sequence;
The second layer II includes four second waverod units 20 connected in sequence, and the four first waverod units 10 are respectively arranged opposite to and connected with the four second waverod units 20;
The third layer III includes two unconnected third waverod units 30, wherein one third waverod unit 30 is connected with two adjacent second waverod units 20, and the other third waverod unit 30 is connected with two other adjacent second waverod units 20;
The fourth layer IV includes a fourth waverod unit 40, and one of the fourth waverod units 40 is connected to two of the third waverod units 30, respectively.
It should be noted that the first, second, third, and fourth are only for distinguishing the waverod units in different layers, and are not limited to the difference between the waverod units, i.e. the waverod units may be the same or different.
According to the valve support, the grid units are arranged at the far end, one gradual change large grid A is formed in the grid unit structure, so that a plurality of gradual change large grids A are formed at the far end (namely corresponding to the coronary section), when the valve support is implanted into an aortic valve annulus, the gradual change large grids A are large in area, the primary valve leaflets cannot be extruded in the radial direction in the coronary section, so that the coronary blood flow is not affected, the radial space of the valve leaflets can be provided even for some patients with poor coronary conditions (the primary valve leaflet height is greater than that of the coronary orifice), the valve leaflets cannot be extruded on the inner wall of the sinus to affect the coronary blood flow, the risk that the primary valve leaflets block the coronary orifice is reduced, meanwhile, the grid density of the coronary section is sparse, the radial rigidity of the valve support is lower, under the action of the shared grid She Qian, a part of the valve support can be pulled and deformed, the service life of the valve leaflets is prolonged, and in addition, the formed large grid A can provide a channel for the coronary blood flow and a later period for the PCI.
Preferably, as shown in fig. 1, the shape of the first wave beam unit 10 is V-shaped, the shape of the second wave beam unit 20, the third wave beam unit 30, and the fourth wave beam unit 40 are inverted V-shaped, specifically, may be a V-shaped or inverted V-shaped structure formed by connecting two straight rods, or may be a V-shaped or inverted V-shaped wave beam, which is not limited in the present invention. The number of the first wave rod units 10 in the first layer I is the same as the number of the second wave rod units 20 in the second layer II, the correspondingly arranged first wave rod units 10 and second wave rod units 20 are connected, so that the connection of the first layer I and the second layer II is realized, and a diamond grid B is formed between the oppositely arranged first wave rod units 10 and the second wave rod units 20. One third wave rod unit 30 in the third layer III is connected with two adjacent second wave rod units 20, the other third wave rod unit 30 is respectively connected with the other two adjacent second wave rod units 20, so that the connection of the third layer III and the second layer II is realized, and a diamond grid B' is formed between each third wave rod unit 30 and the two adjacent second wave rod units 20 connected with the third wave rod unit 30. The fourth waverod units 40 in the fourth layer IV are respectively connected with the two third waverod units 30 in the third layer III, so that the connection of the fourth layer IV and the third layer III is realized, and a gradual large grid a is formed between the fourth waverod units 40 and the two third waverod units 30.
Preferably, as shown in fig. 2 and 3, the fourth wave beam unit 40 is connected to the third wave beam unit 30 by an axial straight beam member 50. Specifically, after the two third waverod units 30 of the third layer III are respectively connected with the second waverod units 20 of the second layer II, two diamond grids B 'are formed, the vertices of the two diamond grids B' close to the outflow end extend to the outflow end respectively to form an axial straight rod piece 50, and the fourth waverod unit 40 of the fourth layer IV is connected with the axial straight rod piece 50 so as to be connected with the third waverod unit 30 of the fourth layer IV. Generally, the number of axial bars 50 is greater than or equal to 3, and a portion of the axial bars 50 may be used as leaflet sewing bars, for example, 3 axial bars 50 are selected as leaflet sewing bars for subsequent skirt and/or leaflet fixation in the manufacture of the valve prosthesis.
The plurality of grid cells may be distributed continuously or discontinuously in the circumferential direction. The continuous distribution means that the adjacent first layers I of 2 grid cells shown in fig. 1 are directly connected, and the discontinuous distribution means that other grids are also arranged between the adjacent first layers I of 2 grid cells shown in fig. 1, and are not directly connected. Preferably, the grid units are continuously distributed along the circumferential direction, and the number of the distributed grid units is more than or equal to 3 and less than or equal to 6, so that the diameter after being pressed and held can be reduced, the diameter of the conveying system can be further reduced, and complications are reduced. As shown in fig. 3, 3 grid cells are arranged continuously, and another fourth wave rod cell 40 is disposed between the fourth wave rod cells 40 of the 3 IV-th layer, and a large grid a 'identical to the large grid a is formed between the another fourth wave rod cell 40 and two adjacent grid cells, and the large grid a' is a common grid between the two adjacent grid cells. It is understood that when the number of the grid units is 3, the 3 grid units can be ensured to be arranged in a trisection axisymmetric manner in the circumferential direction of the valve support, so that the valve prosthesis can be formed by subsequently suturing three valve leaflets, and meanwhile, the number of the circumferential grids in the coronary section can be ensured to be small.
Preferably, to design a lower aortic valve stent, the total number of layers of the valve stent is 4 or 5, which can make the valve stent lower in height in the axial direction, the lower valve stent is easier to deliver, and the over-bowing performance of the stent and the coaxiality with the native annulus after implantation are improved. When the total layer number is 4, the first layer I to the fourth layer IV of the grid unit are respectively located in the first layer to the fourth layer of the valve support. When the total layer number is 5, please refer to fig. 2 and 3, the first layer I to the fourth layer IV of the mesh unit are located in the second layer to the fifth layer of the valve stent respectively, and a wave rod unit is added at the inflow end of the first layer I of the mesh unit to form the first layer of the valve stent. When the total number of layers of the valve stent is 4, the two-layer wave rod unit group at the far end of the valve stent is a coronary section, and the two-layer wave rod unit group at the near end is an anchoring section. As shown in fig. 2, when the total layer number of the valve stent is 5, the two-layer wave rod unit group at the distal end of the valve stent is a coronary section, and the three-layer wave rod unit group at the proximal end is an anchoring section. It will be appreciated that the term "set of waver-bar units" as used herein refers to a plurality of waver-bar units in each layer of the valve stent, each waver-bar unit having a V-shape or an inverted V-shape.
However, when the number of layers of the valve stent in the axial direction is small, the defect of insufficient radial supporting force is caused, so that in actual clinic, the radial supporting force of the valve stent is required to be ensured, and the height is required to be ensured not to be too high so as to influence coronary blood flow. Based on this, in the embodiment of the present invention, the anchoring section at the proximal end of the valve stent includes a plurality of wave rod unit groups, the wave rod unit groups include circumferentially connected wave rod units, the number and the size of the wave rod units in each wave rod unit group are the same, and two adjacent wave rod unit groups form a layer of circumferentially continuous grid. Referring to fig. 2 and 3, the anchoring section at the proximal end of the valve stent includes three layers of wave rod unit groups, the first layer of wave rod unit group is located at the inflow end, the wave rod units in the first layer of wave rod unit group, the second layer of wave rod unit group and the third layer of wave rod unit group are sequentially connected along the circumferential direction, and the wave rod units of two adjacent layers are connected, so that two layers of grids (namely, a hexagonal grid C and a diamond grid B in fig. 2 and 3 located at the bottommost layer) which are continuously and uniformly distributed along the circumferential direction can be formed at the proximal end of the valve stent, thereby enabling the anchoring section at the proximal end of the valve stent to provide a larger radial supporting force.
In this embodiment, the end point of the large mesh a in the valve stent, which is close to the inflow channel (i.e., the connection point a of the first wave rod unit 10 of the first layer I and the second wave rod unit 20 of the second layer II of the mesh units shown in fig. 2), is lower than the coronary artery, so that the coronary artery is not blocked, and the height of the valve stent can be greatly reduced on the premise of ensuring the radial supporting force, thereby reducing the risk to the coronary artery.
As shown in fig. 2 and 3, the anchoring section at the proximal end of the valve stent comprises 12 hexagonal cells C, which 12 cells are equally distributed consecutively in the circumferential direction. In other embodiments the mesh within the anchoring section at the proximal end of the valve stent may also be diamond-shaped (e.g., diamond-shaped mesh B). The number of meshes of the anchoring section in the circumferential direction may depend on the actual conditions, and is generally composed of 9 to 24 (for example 12/15/18/24). In the axial direction, in order to avoid that the high density mesh blocks the coronary, the height of the mesh of the anchoring section is generally made below the coronary orifice. The mesh of the coronary section is connected with the mesh of the anchoring section, and can be cut as a whole, or can be mechanically welded or connected in a matching way. The density of the grid in the coronary section is lower than that of the anchoring section, and the grid area is large, so that enough space can be reserved for the coronary channel, and in addition, the channel can be provided for the PCI catheter if PCI operation is clinically required. In addition, when the height of the anchoring section is low, the leaflet free edge can be sutured to the coronary section in order not to affect the leaflet open and close height, which reduces the overall height of the valve.
The valve stent provided by the invention can be applied to a ball expansion type stent and also can be applied to a self-expansion type stent, when the valve stent is applied to the self-expansion type stent, corresponding structures can be arranged at two ends of the valve stent according to requirements so as to realize connection with a conveying system, for example, hanging lugs, stay wire holes and the like can be added, and the description is omitted.
In summary, the valve stent provided by the invention has the following beneficial effects:
When the valve stent is implanted into the aortic annulus, the formed gradual change large grids have larger areas, the gradual change large grids can not extrude the primary valve leaflets in the radial direction in the coronary section, so that the coronary blood flow is not influenced, the radial space of the valve leaflets can be provided for patients with poor coronary conditions (the primary valve leaflets are higher than the coronary orifices), the valve leaflets are not extruded on the inner wall of the sinus to influence the coronary blood flow, the risk that the primary valve leaflets block the coronary orifices is reduced, meanwhile, the grid density of the coronary section is sparse, the radial rigidity of the valve stent is lower than that of the sparse grid, the valve stent can share a part of traction deformation under the action of the valve She Qian, so that the service life of the valve leaflets is prolonged, and in addition, the formed gradual change large grids can provide channels for the coronary blood flow and also can provide channels for later PCI.
Based on the same inventive concept, the invention also provides a valve prosthesis, which comprises a valve leaflet and a valve bracket as described above, wherein the valve leaflet is fixed on the valve bracket, and the specific fixing method can be seen in the prior art and is not repeated herein.
The valve prosthesis also has all the advantages of the valve stent because the valve stent is provided with the valve stent, namely, a plurality of gradual-change large grids are formed in the coronary region, when the valve stent is implanted into an aortic valve annulus, the gradual-change large grids formed do not squeeze native valve leaflets in the radial direction, so that the risk that the native valve leaflets block coronary orifices is reduced, meanwhile, the grid density of the coronary region is sparse, the radial rigidity of the valve stent is lower due to the sparse grid, the valve stent can share a part of traction deformation under the action of the valve She Qian, so that the service life of the valve leaflets is prolonged, and in addition, the gradual-change large grids formed can provide channels for coronary blood flow and also can provide channels for later PCI.
It is noted that relational terms such as first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises an element.
The above description is only illustrative of the preferred embodiments of the present invention and is not intended to limit the scope of the present invention, and any changes and modifications made by those skilled in the art in light of the above disclosure are intended to fall within the scope of the appended claims. It will be apparent to those skilled in the art that various modifications and variations can be made to the present invention without departing from the spirit or scope of the invention. Thus, it is intended that the present invention also include such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof.