Aortic arch filter

Abstract

The present invention belongs to the field of medical device technology, specifically relating to an aortic arch filter. The filter comprises: a flexible, hollow stent structure with openings at both distal and proximal ends; and a filter aperture disposed on the stent structure, connecting the interior and exterior of the stent structure. The filter aperture has a wavy outer contour. Compared to conventional elliptical filter apertures, the present invention utilizes a wavy filter aperture, which offers increased support and can withstand greater pressure from the aortic arch without collapsing.

Description

Technical Field

[0001] The present invention belongs to the technical field of medical devices, and in particular relates to an aortic arch filter. Background Art

[0002] Cardiogenic emboli are a common cause of various medical conditions, including stroke and other cardiovascular diseases. Cardiogenic emboli can arise from a variety of causes, including atrial fibrillation and valvular heart disease. Cardiogenic emboli contribute to approximately 20% of strokes, making them the fifth most common cause of death and a leading cause of disability. The term "stroke" is used to describe a decrease in blood supply to the brain caused by a blocked artery, typically the middle cerebral artery or one of its branches. This reduction in blood supply can temporarily or permanently impair brain function, with patients experiencing loss of vision, speech, or limb control.

[0003] The PCT patent: WO2021048855A1 "Device and method for controlling the flow of embolic material" discloses an aortic arch filter with a larger filter mesh and is relatively flexible. However, its supporting force is weak, and it is easy for blood to be continuously washed away by the beating of the heart. During use, the filter mesh will also accumulate blood clots, so the resistance of the filter mesh to blood passing through will also increase, and the blood flow in the aortic arch is large, so if the aortic arch filter does not have sufficient supporting force, it is very easy to be displaced. Furthermore, it is not easy to use barbs, hanging pieces, etc. to pierce the tissue to fix the aortic arch filter. Once the barbs pierce the aortic arch, aortic dissection is likely to form, which is likely to cause the death of the patient. Summary of the Invention

[0004] The present invention aims to provide an aortic arch filter to solve the technical problems that the existing aortic arch filter cannot filter blood after thrombus accumulation, and cannot withstand the pressure from the aortic arch under blood flushing.

[0005] An aortic arch filter, comprising:

[0006] A stent structure, which is bendable, hollow inside, and has openings at the distal end and the proximal end;

[0007] a filter hole, provided on the support structure, connecting the inside and outside of the support structure;

[0008] The outer contour of the filter hole is in a wavy line shape.

[0009] As a preferred solution, the filtering hole has at least two blood channels, and the at least two blood channels are interconnected in sequence and connected through an arc connecting segment to form the wavy shape.

[0010] As a preferred solution, the arc connecting segment is arranged tangentially to the blood channel connected thereto.

[0011] As a preferred embodiment, the filter hole has three blood channels, which are the first channel, the second channel and the third channel from the proximal end to the distal end respectively. The diameter of the first channel is R1, the diameter of the second channel is R2, and the diameter of the third channel is R3. The diameter R1 of the first channel is larger than the diameter R2 of the second channel and the diameter R3 of the third channel.

[0012] As a preferred solution, R2=R3, R2+5mm=R1.

[0013] As a preferred solution, the center distance between the first channel and the second channel is greater than the center distance between the second channel and the third channel.

[0014] As a preferred solution, the filtering hole has two blood channels, which are the first channel and the fourth channel from the proximal end to the distal end respectively.

[0015] As a preferred solution, the diameter of the first channel is equal to or smaller than the diameter of the fourth channel.

[0016] As a preferred solution, the radii of the inscribed circles of the first channel, the second channel and the third channel are R5, R6 and R7 respectively, and then R5>R6=R7.

[0017] As a preferred solution, the radius of the inscribed circle of the fourth channel is R8, and R8>R5.

[0018] As a preferred solution, the stent structure is a radially expandable tubular structure.

[0019] As a preferred solution, the support structure is a curved elastic support structure formed by cutting a straight tube and then undergoing heat setting treatment.

[0020] As a preferred solution, the support structure includes:

[0021] A middle enclosure, an open ring structure, is provided with a filter hole bracket, the openings at both ends of the middle enclosure are respectively fixedly connected to the filter hole bracket, and the inner wall of the filter hole bracket is in the wavy line shape to enclose the filter hole;

[0022] A proximal ring, an annular structure, with a distal end fixedly connected to the proximal end of the filter hole bracket;

[0023] A distal ring is an annular structure, and the proximal end is fixedly connected to the distal end of the filter hole bracket.

[0024] As a preferred solution, the outer wall of the filter hole bracket adopts the same shape as its inner wall.

[0025] As a preferred solution, the proximal ends of the two end openings of the middle girth are respectively fixedly connected to the proximal girth, and the distal ends of the two end openings of the middle girth are respectively fixedly connected to the distal girth.

[0026] As a preferred solution, the middle enclosure is a hollow open ring structure formed by a plurality of bracket bodies connected in a smooth manner in sequence, and the proximal enclosure and the distal enclosure are both hollow ring structures formed by a plurality of bracket bodies connected in a smooth manner in sequence.

[0027] As a preferred embodiment, the proximal end or distal end of the openings at both ends of the middle enclosure is fixedly connected to one or more of the bracket bodies, and the proximal end or distal end of the openings at both ends of the middle enclosure is fixedly connected to the proximal enclosure or distal enclosure through the bracket body.

[0028] As a preferred embodiment, the bracket body is at least one of a wave shape, a V shape, a W shape, an inverted Z shape, an elliptical ring shape, a circular ring shape or a hollow diamond shape.

[0029] As a preferred embodiment, the middle enclosure is a hollow open ring structure formed by a bracket body with multiple hollow diamond structures. In the middle enclosure, the axial length of the hollow diamond structure away from the filter hole bracket is the smallest, and the axial length of the hollow diamond structure closer to the filter hole bracket is longer.

[0030] As a preferred solution, the proximal girth and the distal girth are hollow annular structures formed by a stent body with multiple hollow rhombus structures, and at least one of the proximal girth or the distal girth adopts a double-layer hollow rhombus structure.

[0031] As a preferred embodiment, the hollow diamond structure is surrounded by connecting rods. In the double-layer hollow diamond structure, the connecting rods away from the middle enclosure are recessed inward to form a concave hollow diamond grid, and the connecting rods close to the middle enclosure are protruded outward to form a convex hollow diamond grid. The connecting sides of the concave hollow diamond grid and the convex hollow diamond grid share the connecting rods.

[0032] As a preferred solution, the inner hollow diamond grid in the double-layer hollow diamond structure is fixedly connected to the filter hole bracket.

[0033] As a preferred solution, the side wall of the distal end or the proximal end of the filter hole bracket is formed by the two connecting rods of the inner hollow diamond grid.

[0034] As a preferred solution, in the double-layer hollow diamond structure, the hollow diamond grids far away from the filter hole support are larger than the hollow diamond grids close to the filter hole support.

[0035] As a preferred solution, three outwardly protruding hollow diamond grids are respectively provided on both sides of the filter hole bracket, and the convex hollow diamond grids are connected end to end. The convex hollow diamond grids on both sides are respectively fixedly connected to the convex hollow diamond grids on the proximal circumference and the distal circumference on both sides.

[0036] As a preferred embodiment, the three convex hollow diamond grids on both sides of the filter hole bracket are respectively the first convex hollow diamond grid, the second convex hollow diamond grid and the third convex hollow diamond grid from the proximal end to the distal end. By adjusting the circumferential length of the first convex hollow diamond grid, the second convex hollow diamond grid and the third convex hollow diamond grid, the circumferential length of the corresponding position of the filter hole bracket is adjusted, and by adjusting the axial length of the first convex hollow diamond grid, the second convex hollow diamond grid and the third convex hollow diamond grid, the axial length of the corresponding position of the filter hole bracket is adjusted.

[0037] As a preferred solution, the circumferential length of the first convex hollow diamond lattice is L1, the circumferential length of the second convex hollow diamond lattice is L2, and the circumferential length of the third convex hollow diamond lattice is L3, L1<L2=L3.

[0038] As a preferred solution, the middle enclosure is a hollow open ring structure formed by a bracket body with multiple hollow diamond structures. The number of hollow diamond grids in the middle enclosure is even, and the opening of the middle enclosure is fixedly connected to the convex hollow diamond grids on both sides of the filter hole bracket.

[0039] As a preferred solution, in the middle enclosure, the four sides of the hollow rhombus lattice have the same length, and the hollow rhombus lattice is a regular rhombus lattice with an internal angle of 90°.

[0040] As a preferred embodiment, the aortic arch filter further comprises:

[0041] A braided membrane, which is permeable to blood, is disposed on the surface of the stent structure.

[0042] As a preferred solution, a thrombolytic agent is provided on the inner surface of the braided membrane located on the inner wall of the stent structure to dissolve thrombi deposited on the inner surface of the braided membrane.

[0043] As a preferred embodiment, the aortic arch filter further comprises:

[0044] A filter screen is fixed on the support structure and covers the filter holes.

[0045] As a preferred solution, the filter screen has a concave arc-shaped ridge that is recessed toward the inner side of the support structure.

[0046] As a preferred solution, a thrombolytic agent is provided on the surface of the filter to dissolve the thrombus deposited on the filter.

[0047] As a preferred solution, the filter screen is directly fixed on the support structure at the outer edge of the filter hole.

[0048] As a preferred embodiment, the aortic arch filter further comprises:

[0049] a mesh edge detachably disposed on the filter hole;

[0050] The filter screen is fixed on the screen edge.

[0051] The positive progress of the present invention is that the present invention uses an aortic arch filter, which has the following advantages:

[0052] 1. When the filter of the present invention is set in the aortic arch, the filter provides support force to the aortic arch, and the aortic arch provides a compressive force to the filter. The present invention adopts a wavy filter hole. Compared with the traditional elliptical filter hole structure, its support force is increased and it can withstand greater pressure from the aortic arch without being crushed.

[0053] 2. The design of multiple blood channels in the filter hole can independently supply blood to the three branches of the aortic arch.

[0054] 3. Adjacent blood channels are connected by arc connecting sections, and the connecting sections are tangent to the blood channels, which reduces stress concentration and increases fatigue life.

[0055] 4. Since the aortic arch is curved, the implanted filter in the aortic arch also needs to be bent. However, traditional stents implanted in the aortic arch all adopt a method of no connection or single-point connection between the supporting metals. The bending support force is mainly provided by the covering, so its bending support force is relatively weak. The present invention adopts a three-section stent structure of proximal periphery, middle periphery and distal periphery, which shortens the length of the filter and reduces the bending amplitude. The connection relationship between the three and the filter hole stent is conducive to increasing the ability of the filter to resist external force after bending, thereby increasing the bending support force.

[0056] 5. The surface of the stent structure is covered with a blood-permeable woven membrane instead of a sealed material membrane. This ensures to a certain extent that if the filter is blocked, blood can penetrate the woven membrane and pass through the gap between the aortic arch and the stent structure to provide a small amount of blood supply to the three branches.

[0057] 6. Thrombolytic agents are also added to the inner surface of the braided membrane, so that thrombi deposited on the surface of the filter of the present invention will also be dissolved, which not only prevents thrombi from entering the brachiocephalic trunk, left common carotid artery and left subclavian artery, but also plays a role in clearing thrombi in the blood. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] Figure 1 This is a schematic structural diagram of an embodiment of the present invention;

[0059] Figure 2 This is a schematic structural diagram of an embodiment of the filter screen of the present invention;

[0060] Figure 3 This is a schematic structural diagram of an embodiment of the support structure of the present invention;

[0061] Figure 4 for Figure 3 Side view of

[0062] Figure 5 This is a schematic structural diagram of another embodiment of the support structure of the present invention;

[0063] Figure 6(a) and (b) show Figure 5 Side view of;

[0064] Figure 7 for Figure 5 A top view of

[0065] Figure 8 This is a schematic structural diagram of another embodiment of the support structure of the present invention;

[0066] Figure 9 This is a schematic structural diagram of an embodiment of the present invention in which the filter holes are three blood channels;

[0067] Figure 10 This is a structural diagram of an embodiment of the present invention in which the filter holes are two blood channels;

[0068] Figure 11 This is a schematic structural diagram of another embodiment of the present invention in which the filter holes are three blood channels;

[0069] Figure 12 This is a schematic structural diagram of another embodiment of the present invention in which the filter holes are two blood channels;

[0070] Figure 13 This is a schematic diagram of an application of the present invention;

[0071] Figure 14 This is a schematic diagram of the state of blood flushing the filter in the prior art. DETAILED DESCRIPTION

[0072] In order to make the technical means, creative features, objectives and effects achieved by the present invention easier to understand, the present invention is further described below with reference to specific illustrations.

[0073] In the present invention, when describing the filter of the present invention, "proximal end" refers to the side of the filter located on the delivery device or the side in the direction of the end manipulated by the user, and accordingly, "distal end" refers to the side of the filter away from the delivery device or the side away from the end manipulated by the user.

[0074] In the present invention, when describing the filter of the present invention, the "proximal end" refers to the side of the filter close to the apex of the heart, and correspondingly, the "distal end" refers to the side of the filter away from the apex of the heart.

[0075] Reference Figure 1 , an aortic arch filter includes a stent structure 100 and a filter hole 200.

[0076] The stent structure 100 is bendable and hollow inside, with openings at the distal and proximal ends. The stent structure 100 serves as a support member for the filter and is used to support it at a target position, such as at the connection between the aortic arch and three branches (brachiocephalic trunk, left common carotid artery and left subclavian artery) after bending. The hollow stent structure 100 is used for the normal flow of blood.

[0077] The filter holes 200 are provided on the support structure 100, connecting the inside and outside of the support structure 100. In actual operation, the filter holes 200 face the three branches, connecting the aortic arch and the three branches, allowing the blood in the aortic arch to flow into the three branches. Figure 3 、 Figure 5 、 Figures 7 to 12 , the outer contour of the filter hole 200 is a wavy line shape.

[0078] In some embodiments, the wavy shape of the outer contour of the filter hole 200 is also called a candied haws shape.

[0079] When the filter is placed within the aortic arch, it provides support to the arch, which in turn compresses the filter. The present invention utilizes wavy filter holes 200, which, compared to conventional elliptical filter holes, provide increased support and can withstand greater pressure from the aortic arch without collapsing. For example, the aortic arch filter disclosed in PCT patent WO2021048855A1 has elliptical filter holes, which are susceptible to deformation due to compression.

[0080] In some embodiments, reference Figure 9 Zhihe Figure 12 The filter hole 200 has at least two blood channels, and the at least two blood channels are connected in sequence and connected by an arc connecting segment to form a wavy line shape.

[0081] In some embodiments, the arc connecting segment is tangent to the blood channel it connects to. Adjacent blood channels are connected by arc connecting segments, and the connecting segments are tangent to the blood channels, which reduces stress concentration and increases fatigue life.

[0082] In some embodiments, reference Figure 9 The filter hole 200 has three blood channels, namely the first channel 210, the second channel 220 and the third channel 230 from the proximal end to the distal end. The diameter of the first channel 210 is R1, the diameter of the second channel 220 is R2, and the diameter of the third channel 230 is R3. The diameter R1 of the first channel is larger than the diameter R2 of the second channel and the diameter R3 of the third channel.

[0083] The filter of the present invention is usually used in the aortic arch, which has three branches, namely the brachiocephalic trunk, the left common carotid artery and the left subclavian artery. The corresponding filter hole 200 is provided with three blood channels, the first channel 210 corresponds to the thickest brachiocephalic trunk, the second channel 220 and the third channel 230 correspond to the left common carotid artery and the left subclavian artery respectively.

[0084] In some embodiments, R2 = R3, R2 + 5 mm = R1. Since the brachiocephalic trunk corresponding to the first channel is usually thicker, the three channels can achieve independent blood circulation through the above reasonable design.

[0085] Multiple blood channels are connected in sequence, and adjacent portions are connected by arc connecting segments to form a wavy shape. Therefore, when the filter hole 200 has three blood channels, the first channel 210, the second channel 220 and the third channel 230 are connected in sequence, and the first channel 210 and the second channel 220 are connected by two arc connecting segments 251 to form a wavy shape, and the second channel 220 and the third channel 230 are connected by two arc connecting segments 252 to form a wavy shape.

[0086] In some embodiments, generally, the distance between the brachiocephalic trunk and the left common carotid artery is greater than the distance between the left common carotid artery and the left subclavian artery, so that:

[0087] The center distance between the first channel 210 and the second channel 220 is D12, and the center distance between the second channel 220 and the third channel 230 is D23. Therefore, D12>D23.

[0088] In some embodiments, under some special circumstances, the distance between the left common carotid artery and the left subclavian artery is very close, and clinically, the two arteries may even grow together. Therefore, the second channel 220 and the third channel 230 may be combined into a larger fourth channel 240:

[0089] Reference Figure 10The filter hole 200 has two blood channels, which are a first channel 210 and a fourth channel 240 from the proximal end to the distal end. The first channel 210 and the fourth channel 240 are connected by two arc connecting segments 253 to form a wavy line shape.

[0090] In some embodiments, the first channel 210 and the fourth channel 240 have the same diameter. When the diameter of the fourth channel 240 is R4, R1 = R4.

[0091] In some embodiments, the first channel 210 has a smaller diameter than the fourth channel 240 , ie, R1 < R4 .

[0092] In some embodiments, such as Figure 5 In the embodiment shown, since the filter hole bracket 140 is integrated into the entire proximal circumference 110, the middle circumference 120, and the distal circumference 130, the structure of the filter hole of this embodiment needs to be adapted to the bracket shown in this embodiment, such as Figure 11 As shown, the difference between this filter hole and the above-mentioned candied haws-shaped filter hole is that it has protruding tips at both ends, and each channel is not a circle, but a relatively flat circle / or considered to be an ellipse, so the inscribed circle radii of the first channel, the second channel, and the third channel are R5, R6, and R7. When L1, L2, and L3 corresponding to the first convex hollow prism grid, the second convex hollow prism grid, and the third convex hollow prism grid have L1<L2=L3, the inscribed circle radii of the first channel, the second channel, and the third channel are R5, R6, and R7, respectively, such that R5>R6=R7.

[0093] In some embodiments, for the above Figure 11 In the embodiment shown, in some special cases, the distance between the left common carotid artery and the left subclavian artery is very close, and clinically it is found that the two will grow together directly. Therefore, the second channel 220 and the third channel 230 can be combined into a larger fourth channel 240. In this case, the stent is as follows. Figure 12 As shown, it is only necessary to combine the positions of the filter hole bracket 140 corresponding to the second channel 220 and the third channel 230. In order for the filter hole to fit the bracket structure, the inscribed circle radius R8 corresponding to the fourth channel 240 is larger than the inscribed circle radius R5 corresponding to the first channel.

[0094] In some embodiments, the stent structure 100 is a radially expandable tubular structure. The stent structure 100 of the present invention can be contained within a delivery device and delivered to a target location for release. After release, the stent structure 100 can radially expand to form a tubular structure with open ends and a hollow interior to allow blood flow.

[0095] The specific structure of the stent structure 100 can adopt a radially expandable tubular structure in the prior art, and a filter hole 200 is provided on the side wall of the stent structure 100 to connect the inside and outside of the stent structure 100, so as to allow blood to flow out from the stent structure 100 through the filter hole 200. The stent structure 100 can also adopt the following structure:

[0096] In some embodiments, reference Figures 3 and 4 The support structure 100 includes a proximal circumference 110, a middle circumference 120 and a distal circumference 130 from the proximal end to the distal end, and a filter hole support 140 is provided on the middle circumference 120. The proximal circumference 110, the middle circumference 120, the distal circumference 130 and the filter hole support 140 form a radially expandable tubular structure.

[0097] The central ring 120 is an open ring structure, with its two openings fixedly connected to the filter hole bracket 140. The proximal ring 110 is an annular structure, with its distal end fixedly connected to the proximal end of the filter hole bracket 140. The distal ring 130 is an annular structure, with its proximal end fixedly connected to the distal end of the filter hole bracket 140. The inner wall of the filter hole bracket 140 forms the filter hole 200.

[0098] Since the aortic arch is curved, the filter implanted in the aortic arch also needs to be bent. However, the conventional stent implanted in the aortic arch generally adopts a method of no connection or single-point connection between the supporting metals. The bending support force is mainly provided by the coating, which results in its weak bending support force. The filter of the present invention adopts a three-section structure of proximal periphery, middle periphery and distal periphery, which shortens the length of the filter and reduces the bending amplitude. In addition, the proximal end and distal end of the filter hole bracket 140 where the filter hole is located are fixedly connected to the proximal periphery 110 and distal periphery 130 respectively. Figure 13 As shown in , since the bracket is short and the bending amplitude is small, the main deformation of the entire bracket is borne by the filter hole bracket 140, without relying too much on the deformation force generated by the coating, thereby enhancing the ability of the bracket structure 100 to resist external forces after bending.

[0099] In some embodiments, reference Figure 1 、 Figures 3 and 4 The proximal ends of the openings at both ends of the middle enclosure 120 are fixedly connected to the proximal enclosure 110, and the distal ends of the openings at both ends of the middle enclosure 120 are fixedly connected to the distal enclosure 130. The ends of the middle enclosure 120 near the filter hole 200 are also fixedly connected to the distal enclosure 110 and the proximal enclosure 130, respectively, thereby forming a three-point connection between the proximal enclosure 110, the middle enclosure 120, the distal enclosure 130, and the filter hole support 140. The three points form a triangle or are approximately connected by an arc, rather than on a straight line, which is more conducive to increasing the ability to resist external forces after bending and increasing the bending support force.

[0100] The connection mode of the middle circle 120 with the proximal circle 110 and the distal circle 130 can be determined according to the specific structure of the middle circle 120. For example, Figure 4 As shown in , when the middle ring 120 is a hollow open ring structure formed by connecting multiple hollow diamond-shaped bracket bodies, the hollow diamond-shaped bracket bodies near the two ends of the filter hole 200 are stretched at both ends, the proximal end of the hollow diamond-shaped bracket body is fixedly connected to the proximal ring 110, the distal end of the hollow diamond-shaped bracket body is fixedly connected to the distal ring 130, and the middle ring 120 is also fixedly connected to the filter hole bracket 140, thus forming a three-point connection. Figure 4 As shown in the figure, the connection point between the middle circle 120 and the proximal circle 110 is point a, the connection point between the middle circle 120 and the filter hole bracket 140 is point b, and the connection point between the middle circle 120 and the distal circle 130 is point c. The three points a, b and c are connected to form an approximate arc, which is more conducive to the bending of the bracket.

[0101] Since the side of the middle enclosure 120 away from the filter hole bracket 140 is the compressed side of the bend, that is, the space is compressed, and both sides are compressed, while the ends of the proximal enclosure 110 and the distal enclosure 130 away from the filter hole bracket 140 are free and basically not compressed, that is, the space compression is less, so the side of the middle enclosure 120 away from the filter hole bracket 140 is more compressed than the side of the proximal enclosure 110 and the distal enclosure 130 away from the filter hole bracket 140, and the space compression is large, and the closer to the filter hole bracket 140 the side is, the less compressed it is, and it may even be subjected to tension, that is, the larger the space, so the middle enclosure 120 as a whole adopts a hollow rhombus-shaped bracket body whose axial length is the smallest on the side away from the filter hole bracket 140 and the closer to the filter hole bracket 140 the position, the longer the axial length is. It should be stated that the stent is cut from a straight steel pipe, so the figure shows a straight structure. After heat setting treatment, the stent will bend to use the curved aortic arch. Therefore, the tension and compression mentioned above refer to the change in the spatial size of the stent, rather than the straight stent entering the human body and bending under the external force of the aortic arch. This is because the stent is heat-treated and shaped before entering the human body, and it is curved in itself. However, the stent is elastic and can become straight under the action of external force, so that it can be delivered into the human body using a delivery device. After being released at the aortic arch, it will automatically restore the curved state.

[0102] In some embodiments, reference Figure 5As shown, in order to increase the fixation stability of the stent after implantation, the length of the stent is increased to a certain extent, so the proximal periphery 110 is set as a double-layer hollow diamond structure, or the distal periphery 130 is set as a double-layer hollow diamond structure, or the proximal periphery 110 and the distal periphery 130 are both set as double-layer hollow prismatic structures, and the connecting rods of the hollow prismatic grids on the outer side (i.e., away from the center) of the double-layer hollow prismatic structure are concave inward to form a "concave hollow prismatic grid", the main purpose of which is to In order to facilitate the placement of the stent into a delivery device after compression, the connecting rods of the hollow prismatic cells on the inner side (i.e., near the center) of the double-layer hollow prismatic structure are convex outward to form "convex hollow prismatic cells." The main purpose is to provide greater circumferential support for the stent, so that the stent can be firmly attached to the inner wall of the aortic arch. The concave hollow prismatic cells and the convex hollow prismatic cells share a connecting rod at the connection side. The inner hollow prismatic cells of the double-layer hollow prismatic structure are fixedly connected to the filter hole stent 140.

[0103] Furthermore, the distal end and the proximal end of the filter hole bracket 140 utilize the two connecting rods of the inner hollow prism grid of the double-layer hollow prism structure to jointly form the filter hole bracket 140, so that the proximal end and the distal end of the filter hole bracket 140 are more integrated into the proximal circumference 110 or the distal circumference 130, thereby increasing the stability of the connection between the proximal end and the distal end of the filter hole bracket 140 and the proximal circumference 110 or the distal circumference 130.

[0104] Furthermore, the proximal circumference 110 or the distal circumference 130 of the double-layer hollow prism structure, taking the proximal circumference as an example, in order to reduce the weight of the bracket, the hollow prism grid on the side of the proximal circumference away from the filter hole bracket 140 is set to a larger diamond grid, that is, multiple hollow diamond grids are replaced by one larger diamond grid.

[0105] Furthermore, three outwardly protruding convex hollow prisms are provided on both sides of the filter hole bracket 140, and the convex hollow prisms are connected end to end, and the convex hollow prisms on both sides are fixedly connected to the convex hollow prisms of the proximal circumference 110 and the distal circumference 130 respectively. The main bending holding force is not only provided by the filter hole bracket 140, but the convex hollow prisms provided on both sides of the filter hole bracket 140 also provide the bending holding force of the bracket, effectively increasing the bending support force of the bracket, and at the same time, the proximal circumference 110 / distal circumference 130 and the middle circumference 120 (the middle circumference 120 described here includes the filter hole bracket 140 and the convex hollow prisms provided on both sides of the filter hole bracket 140) form a multi-point connection, which effectively improves the overall stability of the bracket.

[0106] Furthermore, three outwardly convex hollow prisms are provided on both sides of the filter hole bracket 140, and the convex hollow prisms are arranged from the proximal periphery 110 to the distal periphery 130 as a first convex hollow prism, a second convex hollow prism, and a third convex hollow prism. The circumferential length of the first convex hollow prism is L1, the circumferential length of the second convex hollow prism is L2, and the circumferential length of the third convex hollow prism is L3. By adjusting the size of L1, L2, and L3, the circumferential length of the corresponding filter hole bracket 140 position can be adjusted. Length, for example, when L1 becomes smaller, the circumferential length of the filter hole bracket 140 at the corresponding position of the first convex hollow prism grid becomes larger, and vice versa. Preferably, the L1<L2=L3. Similarly, by changing the axial lengths corresponding to the first convex hollow prism grid, the second convex hollow prism grid, and the third convex hollow prism grid, the axial lengths of the corresponding filter hole bracket 140 positions can also be adjusted. The only difference is that when the axial length of the convex hollow prism grid increases, the axial length of the corresponding filter hole bracket 140 position also increases, and vice versa.

[0107] Furthermore, since the middle enclosure 120 is composed of larger diamond grids, and the number of diamond grids is an even number, the opening of the middle enclosure 120 is fixedly connected to the convex hollow prism grid, for example, 2, 4, 6, 8, 10, 12, 14 ..., but generally not more than 24, because this is related to the size of the diamond grid, and the size of the diamond grid is easy to obtain by adjusting the number of diamond grids and the size of the bracket, so it will not be repeated. Compared with the gradual hollow diamond bracket body in the previous embodiment, this embodiment uses diamond grids of the same size because this embodiment The number of diamond grids in the example is an even number, and the side of the middle circumference 120 relatively far away from the filter hole bracket 140 is exactly the connection point of the adjacent diamond grids, and the axial length of the connection point is significantly shorter than the axial length of the proximal section and the distal end of the diamond grid, so the axial length of the side of the middle circumference 120 relatively far away from the filter hole bracket 140 is smaller. Therefore, there is no need to use diamond grids with gradually changing sizes to achieve the beneficial effects brought by the gradually changing hollow diamond bracket body in the previous embodiment. However, the design of an even number of diamond grids actually makes use of the structural characteristics of the diamond grid body to achieve the above-mentioned beneficial effects.

[0108] Further, such as Figure 5 As shown, the lengths of the four sides of the prismatic grid used in this embodiment are basically the same. This is because the axial length of the prismatic grid is much larger than the circumferential length, which will cause its circumferential support force to be weaker (the circumferential direction refers to the direction along the outer surface of the bracket and perpendicular to the axis), and will also increase the material utilization rate. If the circumferential length of the prismatic grid is much larger than the axial length, it will cause the bracket to be difficult to press and grip. Therefore, the prismatic grid with four sides of basically the same length selected here can be further regarded as a regular prismatic grid with an internal angle of 90°, so as to achieve a balance between the pressing and gripping performance of the bracket and the lightweight material.

[0109] For another example, as shown in FIG6 (a), when the middle circumference 120 is a hollow open ring structure formed by connecting elliptical bracket bodies, the proximal end or distal end of the elliptical bracket body close to the two ends of the filter hole 200 is connected to one or more elliptical bracket bodies. The number of elliptical bracket bodies can be determined according to the length of the proximal and distal ends of the filter hole bracket 140. The middle circumference 120 is fixedly connected to the proximal end or distal end by means of the elliptical bracket body. The middle circumference 120 is also fixedly connected to the filter hole bracket 140, thus forming a three-point connection. Figure 4 As shown in the figure, the connection point between the middle enclosure 120 and the proximal enclosure 110 by means of the elliptical bracket body is point a, the connection point between the middle enclosure 120 and the filter hole bracket 140 is point b, and the connection point between the middle enclosure 120 and the distal enclosure 130 by means of the elliptical bracket body is point c. The three points a, b and c are connected to form an approximate arc.

[0110] In some embodiments, reference Figures 3 to 8 The middle enclosure 120 is a hollow open ring structure formed by a plurality of bracket bodies connected in sequence and smoothly, and the proximal enclosure 110 and the distal enclosure 130 are both hollow ring structures formed by a plurality of bracket bodies connected in sequence and smoothly.

[0111] In some embodiments, the stent body is at least one of a wave shape, a V shape, a W shape, an inverted Z shape, an elliptical ring shape, a circular ring shape, or a hollow diamond shape. For example, Figure 3 and Figure 4 As shown in FIG, the proximal periphery 110, the middle periphery 120 and the distal periphery 130 all adopt a hollow diamond-shaped bracket body. Figures 5 to 8 As shown in FIG, the proximal enclosure 110 can be viewed as a hollow ring structure formed by a circle of elliptical ring-shaped bracket bodies, a circle of V-shaped bracket bodies, and a further circle. The distal enclosure 130 employs the same structure as the proximal enclosure 110. The intermediate enclosure 120 employs a hollow open ring structure formed by elliptical ring-shaped bracket bodies.

[0112] In some embodiments, when the middle enclosure 120 is fixedly connected to the proximal enclosure 110 or the distal enclosure 130 through the bracket body, the bracket body is also fixedly connected to the filter hole bracket 140 at the end close to the filter hole bracket 140 to further increase the overall bending support force when the filter is bent.

[0113] In some embodiments, when the filter hole bracket 140 is provided, the inner wall of the filter hole bracket 140 is in a wavy shape to enclose the filter hole 200 .

[0114] In some embodiments, the outer wall of the filter hole support 140 adopts the same shape as the inner wall thereof.

[0115] In some embodiments, the aortic arch filter further includes a braided membrane that is permeable to blood and disposed on the surface of the stent structure 100. The present invention utilizes a blood-permeable membrane, rather than a sealed material membrane, to ensure that, if the filter 300 becomes clogged, blood can penetrate the membrane and, through the gap between the aortic arch and the stent structure 100, provide a small amount of blood supply to the three branches.

[0116] In some embodiments, a thrombolytic agent is provided on the inner surface of the braided coating on the inner wall of the stent structure 100. The thrombolytic agent has the function of dissolving blood clots. By providing the thrombolytic agent on the inner surface of the braided coating, the blood clots deposited on the surface of the filter of the present invention will also be dissolved, which not only prevents the blood clots from entering the brachiocephalic trunk, the left common carotid artery and the left subclavian artery, but also plays a role in clearing the blood clots in the blood.

[0117] In some embodiments, the aortic arch filter further comprises a filter mesh 300 fixed to the support structure 100 and covering the filter holes 200. The filter mesh 300 is used to filter blood flowing into the three branches through the aortic arch to prevent thrombus particles from entering peripheral blood vessels through the three branches.

[0118] In some embodiments, reference Figure 1 and Figure 2 The filter 300 has an inwardly concave arc-shaped ridge that is concave toward the inner side of the support structure 100. Figure 2 As shown in FIG, the inner side of the filter 300 is concave to form an arc-shaped arc surface, relative to FIG. Figure 14 The flat filter design shown is not easy to deposit blood clots. Since the blood from the ventricle has a greater impact force, Figure 14 In the figure, the arrow direction is the direction of blood flow. When blood impacts the flat filter 600, it usually gathers in the middle of the filter, causing a large amount of thrombus deposition. The resistance of the filter to blood gradually increases. When the support structure 100 of the filter does not have sufficient support force, it is very easy to move. Therefore, the present invention improves the filter 300, such as Figure 2 As shown in the figure, the filter 300 is designed to have an inwardly concave arc-shaped ridge structure with the middle part concave inward, so that the filter 300 forms an arc-shaped surface as a whole. The direction of the arrow is the direction of blood flow. When the blood hits the filter, it generates a flushing force to both sides, which further reduces the thrombus deposition in the filter and ensures the permeability of the filter.

[0119] In some embodiments, a thrombolytic agent is provided on the surface of the filter 300. The thrombolytic agent has the function of dissolving blood clots. A small amount of blood clots deposited on the filter can also be dissolved by the thrombolytic agent, thereby increasing the service life of the filter and reducing the risk of clogging of the filter.

[0120] In some embodiments, reference Figure 1 , the filter 300 can be directly fixed on the support structure 100 at the outer edge of the filter hole 200. After the present invention improves the above design of the filter 300, the filter does not need to be removed from the filter hole 200. In order to firmly fix the filter 300, the filter 300 of the above design is fixedly connected to the filter hole 200.

[0121] In some embodiments, the aortic arch filter further comprises a mesh edge 400, which is detachably disposed on the filter hole 200. Specifically, the mesh edge 400 is detachably connected to the support structure 100 at the outer edge of the filter hole 200. Figure 2 The filter 300 is fixed on the mesh edge 400 so that the filter 300 is detachably connected to the filter hole 200 through the mesh edge 400. In some implementations, when the filter 300 may need to be disassembled and replaced, the filter 300 can be detachably connected through the mesh edge 400.

[0122] In some embodiments, reference Figure 13 The aortic arch filter is used within the aortic arch 510 to filter blood passing through the aortic arch and prevent blood clots from entering the cerebral arteries and causing a stroke. The aortic arch filter includes a stent structure 100. From the proximal end to the distal end, the stent structure 100 includes a proximal periphery 110, a middle periphery 120, and a distal periphery 130. A filter hole support 140 is provided on the middle periphery 120. The proximal periphery 110, the middle periphery 120, the distal periphery 130, and the filter hole support 140 are connected at three points. The stent structure 100 as a whole is a three-branched structure that bends outward from the middle. After bending, the proximal periphery 110 and the middle periphery 120, and the middle periphery 120 and the distal periphery 130 away from the filter hole support 140 do not contact each other. The inner wall of the filter hole support 140 is surrounded by a wavy filter hole 200. The filter hole 200 has three blood channels: a first channel 210, a second channel 220, and a third channel 230, from the proximal end to the distal end. When configured, the first channel 210 corresponds to the brachiocephalic trunk 520, the second channel 220 corresponds to the left common carotid artery 530, and the third channel 230 corresponds to the left subclavian artery 540. A filter screen 300 (not shown) is fixed to the filter hole bracket 140. The center portion of the filter screen 300 is recessed toward the inside of the filter hole bracket 140, forming an inwardly concave arcuate surface.

[0123] The blood in the aortic arch first flows into the interior of the support structure 100 formed by the proximal pericardium 110, the middle pericardium 120 and the distal pericardium 130, and after being filtered by the filter 300, flows into the brachiocephalic trunk through the first channel 210, flows into the left common carotid artery through the second channel 220, and flows into the left subclavian artery through the third channel 230. Since the filter 300 adopts an inward-concave arc surface structure, thrombus is not easily deposited on the filter 300. Blood with a greater scouring force can also generate a scouring force to both sides, further reducing the thrombus deposition on the filter and ensuring the permeability of the filter. The filter hole 200 with a wavy shape has an increased supporting force and can withstand greater pressure from the aortic arch without being crushed.

[0124] The basic principles, main features, and advantages of the present invention are shown and described above. Those skilled in the art should understand that the present invention is not limited to the foregoing embodiments. The foregoing embodiments and descriptions are merely illustrative of the principles of the present invention. Various changes and modifications may be made to the present invention without departing from the spirit and scope of the present invention. Such changes and modifications are intended to fall within the scope of the present invention. The scope of protection claimed in the present invention is defined by the appended claims and their equivalents.

Claims

1. An aortic arch filter, comprising: A stent structure, which is bendable, hollow inside, and has openings at the distal end and the proximal end; a filter hole, provided on the support structure, connecting the inside and outside of the support structure; The filter hole has an outer contour of a wavy shape, and the filter hole has at least two blood channels, the at least two blood channels are sequentially connected and connected by an arc connecting segment to form the wavy shape, and the arc connecting segment is arranged tangent to the blood channel connected thereto; The support structure comprises: A middle enclosure, an open ring structure, is provided with a filter hole bracket, the openings at both ends of the middle enclosure are respectively fixedly connected to the filter hole bracket, and the inner wall of the filter hole bracket is in the wavy line shape to enclose the filter hole; A proximal ring, an annular structure, with a distal end fixedly connected to the proximal end of the filter hole bracket; A distal ring is an annular structure, and the proximal end is fixedly connected to the distal end of the filter hole bracket.

2. The aortic arch filter according to claim 1, wherein The filter hole has three blood channels, which are the first channel, the second channel and the third channel from the proximal end to the distal end respectively. The diameter of the first channel is R1, the diameter of the second channel is R2, and the diameter of the third channel is R3. The diameter R1 of the first channel is larger than the diameter R2 of the second channel and the diameter R3 of the third channel.

3. The aortic arch filter according to claim 2, wherein R2= R3, R2+5mm= R1.

4. The aortic arch filter according to claim 2, wherein A center distance between the first channel and the second channel is greater than a center distance between the second channel and the third channel.

5. The aortic arch filter according to claim 1, wherein The filtering hole has two blood channels, which are the first channel and the fourth channel from the proximal end to the distal end; The diameter of the first channel is equal to or smaller than the diameter of the fourth channel.

6. The aortic arch filter according to claim 1, wherein The filter hole has three blood channels, which are the first channel, the second channel and the third channel from the proximal end to the distal end. The inscribed circle radii of the first channel, the second channel and the third channel are R5, R6 and R7 respectively, and R5>R6=R7.

7. The aortic arch filter according to claim 1, wherein The filtering hole has two blood channels, which are the first channel and the fourth channel from the proximal end to the distal end. The inscribed circle radii of the first channel and the fourth channel are R5 and R8 respectively, and R8>R5.

8. The aortic arch filter according to claim 1, wherein The stent structure is a radially expandable tubular structure.

9. The aortic arch filter according to claim 1 or 8, wherein the stent structure is a curved elastic stent structure formed by cutting a straight tube and subjecting it to heat setting treatment.

10. The aortic arch filter according to claim 1, wherein The outer wall of the filter hole bracket adopts the same shape as the inner wall thereof.

11. The aortic arch filter according to claim 1, wherein The proximal ends of the openings at both ends of the middle enclosure are respectively fixedly connected to the proximal enclosure, and the distal ends of the openings at both ends of the middle enclosure are respectively fixedly connected to the distal enclosure.

12. The aortic arch filter according to claim 1, wherein The middle enclosure is a hollow open ring structure formed by a plurality of bracket bodies connected in a smooth manner in sequence, and the proximal enclosure and the distal enclosure are both hollow ring structures formed by a plurality of bracket bodies connected in a smooth manner in sequence.

13. The aortic arch filter according to claim 1, wherein The proximal ends or distal ends of the openings at both ends of the middle enclosure are fixedly connected to one or more bracket bodies, and the proximal ends or distal ends of the openings at both ends of the middle enclosure are fixedly connected to the proximal enclosure or distal enclosure through the bracket body.

14. The aortic arch filter according to claim 12 or 13, wherein: The bracket body is at least one of a wave shape, a V shape, a W shape, an inverted Z shape, an elliptical ring shape, a circular ring shape or a hollow diamond shape.

15. The aortic arch filter according to claim 11, wherein The middle circumference is a hollow open ring structure formed by a bracket body with multiple hollow diamond structures. In the middle circumference, the axial length of the hollow diamond structure away from the filter hole bracket is the smallest, and the axial length of the hollow diamond structure closer to the filter hole bracket is longer.

16. The aortic arch filter according to claim 12, wherein The proximal circumference and the distal circumference are hollow annular structures formed by a stent body with multiple hollow rhombus structures, and at least one of the proximal circumference and the distal circumference adopts a double-layer hollow rhombus structure.

17. The aortic arch filter according to claim 16, wherein The hollow diamond structure is surrounded by connecting rods. In the double-layer hollow diamond structure, the connecting rods away from the middle enclosure are recessed inward to form concave hollow diamond grids, and the connecting rods close to the middle enclosure are protruded outward to form convex hollow diamond grids. The connecting sides of the concave hollow diamond grids and the convex hollow diamond grids share the connecting rods.

18. The aortic arch filter according to claim 17, wherein The inner hollow diamond grid of the double-layer hollow diamond structure is fixedly connected to the filter hole bracket.

19. The aortic arch filter according to claim 17, wherein The two connecting rods of the inner hollow rhombus form the side wall of the distal end or the proximal end of the filter hole bracket.

20. The aortic arch filter according to claim 17, wherein In the double-layer hollow diamond structure, the hollow diamond cells away from the filter hole support are larger than the hollow diamond cells close to the filter hole support.

21. The aortic arch filter according to claim 17, wherein Three outwardly protruding hollow diamond grids are respectively provided on both sides of the filter hole bracket, and the convex hollow diamond grids are connected end to end. The convex hollow diamond grids on both sides are respectively fixedly connected to the convex hollow diamond grids on the proximal circumference and the distal circumference on both sides.

22. The aortic arch filter according to claim 21, wherein The three convex hollow diamond grids on both sides of the filter hole bracket are respectively the first convex hollow diamond grid, the second convex hollow diamond grid and the third convex hollow diamond grid from the proximal end to the distal end. By adjusting the circumferential length of the first convex hollow diamond grid, the second convex hollow diamond grid and the third convex hollow diamond grid, the circumferential length of the corresponding position of the filter hole bracket is adjusted, and by adjusting the axial length of the first convex hollow diamond grid, the second convex hollow diamond grid and the third convex hollow diamond grid, the axial length of the corresponding position of the filter hole bracket is adjusted.

23. The aortic arch filter according to claim 22, wherein The circumferential length of the first convex hollow diamond lattice is L1, the circumferential length of the second convex hollow diamond lattice is L2, and the circumferential length of the third convex hollow diamond lattice is L3, L1<L2=L3.

24. The aortic arch filter according to claim 21, wherein The middle enclosure is a hollow open ring structure formed by a plurality of hollow diamond-shaped bracket bodies. The number of hollow diamond grids in the middle enclosure is even, and the opening of the middle enclosure is fixedly connected to the convex hollow diamond grids on both sides of the filter hole bracket.

25. The aortic arch filter according to claim 24, wherein In the middle enclosure, the four sides of the hollow rhombus lattice have the same length, and the hollow rhombus lattice is a regular rhombus lattice with an internal angle of 90°.

26. The aortic arch filter according to claim 1, wherein The aortic arch filter further comprises: A braided membrane, which is permeable to blood, is disposed on the surface of the stent structure.

27. The aortic arch filter according to claim 26, wherein The inner surface of the braided membrane located on the inner wall of the stent structure is provided with a thrombolytic agent to dissolve the thrombus deposited on the inner surface of the braided membrane.

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