Thrombus filter and thrombus filtering system

Abstract

The present application provides a kind of thrombus filter, including support frame and at least one filter screen coated on the support frame, the support frame at least includes adjacent two frames along its axial direction and is arranged from near to far, the surface formed by the support frame is arc surface, in the adjacent two frames, the maximum radial width of one of the frame is D1, the maximum radial width of another of the frame is D2, then define D as the smaller value in D1 and D2, two the frame width of the frame connection along the radial direction at junction is D0, then D0 satisfies: D0 < D, so that at least one side of the support frame portion forms at least one waist structure.The thrombus filter of the present application can increase the fixation stability of the thrombus filter and the compliance along the radial direction, so as to effectively filter the microparticles or particles such as thrombus in the blood flow, and also reduce the possibility of leakage of the support frame edge.

Description

Technical Field

[0001] This invention relates to the field of interventional medical device technology, and in particular to a thrombus filter and a thrombus filtration system. Background Technology

[0002] Cerebral embolism occurs when various emboli (such as mural thrombi in the heart, atherosclerotic plaques, fat, tumor cells, fibrocartilage, or air) travel through the bloodstream into narrow, tortuous cerebral arteries and obstruct the blood flow. When collateral circulation cannot compensate, it causes ischemic necrosis of brain tissue in the area supplied by that artery, resulting in focal neurological deficits. Cerebral embolism commonly occurs in the internal carotid artery system, and is relatively rare in the vertebrobasilar artery system. Cerebral embolism accounts for approximately 15% to 20% of ischemic strokes. About 75% of cardiac emboli embolisms occur in the brain. Common cardiac diseases causing cerebral embolism include atrial fibrillation, valvular heart disease, infective endocarditis, and cardiac myxoma. With advancements in medical technology, an increasing number of cardiac and vascular surgical problems can be addressed through endovascular surgery. Stent implantation and valve replacement are among the rapidly developing endovascular procedures in recent years. Valve replacement surgery primarily involves transcatheter aortic valve implantation (TAVI). A catheter is inserted through the femoral artery to deliver an artificial heart valve to the aortic valve area, where it is opened to restore valve function. The procedure does not require open-chest surgery, resulting in minimal trauma and rapid recovery. When used in conjunction with an anti-embolism filter, valve replacement effectively prevents emboli from entering the brain and causing blockage, further reducing risks.

[0003] Currently, clinical research suggests that effective embolism filtering is necessary for all three branches of the aortic arch to minimize the risk of stroke. Existing anti-embolism filters mostly use a nickel-titanium alloy frame with a filter membrane to block the three branches of the aortic arch. For this type of filter, the nickel-titanium alloy frame is a single, regular closed loop. In clinical applications, when the protective device is implanted into the aortic arch, different areas of the frame, although experiencing different stresses, still influence each other. This prevents adaptive adjustment to ensure both stability and conformity for better fit within the aortic arch, thus avoiding leakage at the frame edges. Summary of the Invention

[0004] Therefore, it is necessary to provide a new thrombus filter and thrombus filtration system to address the problem that the existing support frame of the thrombus filter cannot simultaneously ensure stability and prevent edge leakage.

[0005] On one hand, a thrombus filter is proposed, comprising a support frame and at least one filter screen covering the support frame. The support frame includes at least two adjacent side frames arranged along its axial direction from near to far. The surface formed by the support frame is an arc-shaped surface. Among the two adjacent side frames, the maximum radial width of one side frame is D1, and the maximum radial width of the other side frame is D2. D is defined as the smaller value between D1 and D2. The width of the side frame connected to the two side frames along the radial direction at the connection point is D0. D0 satisfies: D0 < D, thereby forming at least one waist-recessed structure on at least one side portion of the support frame.

[0006] On the other hand, a thrombus filtration system is proposed, comprising a thrombus filter as described above and a delivery device for delivering the thrombus filter.

[0007] In the aforementioned thrombus filter, the maximum radial width of one frame is D1, and the maximum radial width of the other frame is D2. D is defined as the smaller of D1 and D2. The two frames are connected, and the radial width of the frame at the connection point is less than D, thereby forming at least one waist-recessed structure on at least one side portion of the support frame. That is, a portion of at least one side portion of the support frame is recessed towards the interior of the support frame. Taking implantation within the aortic arch as an example, during the process of the thrombus filter being implanted into the appropriate positions at the three branch vessels within the aortic arch and being released and deployed, the two adjacent frames cooperate to fix the thrombus filter within the aortic arch, increasing the stability of the fixation. Simultaneously, their pre-shaped arcuate surfaces support the filter upwards, so that each part of the filter conforms to the inner wall of the three branch vessels within the aortic arch. Furthermore, the at least one waist-tightening structure formed between two adjacent frame sides transforms the support frame from a single, regular closed-loop frame into a regional support frame. The sides of the frame can be adjusted relatively flexibly to increase the radial compliance of the thrombus filter. This allows the support frame to regionally adapt to the structure and size of the aortic arch, ensuring that the support frame is more firmly fixed within the aortic arch and fits more tightly against the inner wall. This enables the thrombus filter to more effectively filter thrombi and other microparticles or particles in the blood flow to the three branch vessels and also reduces the possibility of leakage at the edges of the support frame. Attached Figure Description

[0008] Figure 1 This is a schematic diagram of the overall structure of the thrombus filter in Example 1;

[0009] Figure 2 for Figure 1 A schematic diagram of the structure of a thrombus filter without a filter screen covering it;

[0010] Figure 3 This is a schematic diagram of the thrombus filter implanted in the aortic arch in Example 1;

[0011] Figure 4 This is another structural diagram of the thrombus filter in Example 1 when the filter screen is not covered;

[0012] Figure 5 This is another structural diagram of the thrombus filter in Example 1 without a filter screen;

[0013] Figure 6 for Figure 2 The support frame of the structure shown is placed in a side view on a horizontal plane;

[0014] Figure 7 for Figure 2 The support frame of the structure shown is placed in a top view on a horizontal plane;

[0015] Figure 8 This is a schematic diagram of the overall structure of the thrombus filter in Example 2;

[0016] Figure 9 for Figure 8 A schematic diagram of the structure of a thrombus filter without a filter screen covering it;

[0017] Figure 10 for Figure 8 The diagram shows a thrombus filter implanted in the aortic arch.

[0018] Figure 11 for Figure 10 Another structural diagram of the thrombus filter;

[0019] Figure 12 This is another structural diagram of the thrombus filter in Example 2 when the filter screen is not covered;

[0020] Figure 13 This is a schematic diagram of the thrombus filter in Example 3 when the filter screen is not covered;

[0021] Figure 14 for Figure 13 Enlarged view of point C in the middle;

[0022] Figure 15 This is a schematic diagram of the thrombus filter in Example 4 when the filter screen is not covered. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0024] It should be noted that in the field of interventional medical devices, the end of a medical device implanted in the human or animal body that is closer to the operator is generally called the "proximal end," and the end that is farther from the operator is called the "distal end." Based on this principle, the "proximal end" and "distal end" of any component of a medical device are defined. "Axial direction" generally refers to the length direction of the medical device during delivery, and "radial direction" generally refers to the direction of the medical device perpendicular to its "axial direction." Based on this principle, the "axial direction" and "radial direction" of any component of a medical device are defined.

[0025] The technical solution of the present invention will be further described in detail below with reference to specific embodiments.

[0026] Example 1

[0027] Example 1 presents a thrombus filter 10, used in valve replacement surgery as an example. It is used to block thrombi or lumps in the bloodstream from flowing into the brain through any of the three branches of the aortic arch, thus preventing cerebral embolism. Furthermore, it can be used in open-chest surgery to filter blood, or implanted into blood vessels to filter thrombi or calcifications. Please refer to [reference needed]. Figure 1 The thrombus filter 10 includes a support frame 11 and a filter screen 12 covering the support frame 11, as well as a connector 13 disposed at the proximal end of the support frame 11 for connection to the distal end of the sheath core. Figure 1-2 As shown, the support frame 11 includes a first frame 111 and a second frame 112 arranged adjacent to each other along its axial direction from near to far. The surface formed by the support frame 11 is an arc-shaped surface, which can conform to the shape of the aortic arch and fit well against the inner wall of the three branch vessels of the aortic arch.

[0028] The filter 12 is a membrane made of polymer materials such as PTFE (Polytetrafluoroethylene), TPU (Thermoplastic polyurethanes), or PET (Polyethylene terephthalate). It can also be a woven mesh with multiple holes, made of woven yarns with shape memory properties. In this embodiment, the filter 12 is made of PTFE membrane, and there is only one filter. The edge portion of the filter 12 is fixedly connected to the corresponding portion of the first frame 111 and the second frame 112. The other portion of the filter 12 covers the entire outer surface of the support frame 11 and is supported upwards by the arc-shaped structure of the support frame 11 to better conform to the inner wall of the three branch vessels of the aortic arch. In other implementations, the filter 12 may include two or more independently configured sub-nets that cooperate with each other to cover the entire support frame 11 and are each fixedly connected to a suitable position on the first frame 111 or the second frame 112. For example, the filter 12 may include two sub-nets, one of which covers the first frame 111 and the edge portion of the sub-net is fixed to a suitable position on the first frame 111, and the other sub-net covers the second frame 112 and the edge portion of the sub-net is fixed to a suitable position on the second frame 112.

[0029] The thickness of the filter screen 12 ranges from 10 micrometers to 55 micrometers. The membrane has numerous small pores for filtration, with pore diameters ranging from 25 micrometers to 300 micrometers. The shape and size of the filter screen 12 are similar to or match the shape and size of the support frame 11, provided that the filter screen 12 completely covers the support frame 11 and its edges are securely attached to the first frame 111 and the second frame 112 at appropriate positions. The edges of the filter screen 12 can be secured to the first frame 111 and the second frame 112 using processes such as glue, high-frequency welding, laser welding, or sewing. The filter screen 12 can filter large particles such as blood clots or lumps, as well as small particles such as blood clots or lumps.

[0030] In other implementations, the support frame 11 may be covered with two or more filter screens 12. These filter screens 12 may be completely or partially overlapping, or they may be connected along the axial direction of the thrombus filter 10, as long as they can cover the entire structure of the support frame 11. The size and number of holes in the multiple filter screens 12 may be the same or different, as long as effective filtration can be achieved.

[0031] like Figure 1-2As shown, the first frame 111 is located at the near end of the support frame 11, and the second frame 112 is located at the far end of the support frame 11. The maximum radial width of the first frame 111 is D1, and the maximum radial width of the second frame 112 is D2. D is the smaller of D1 and D2; that is, if D1 > D2, then D = D2; if D1 < D2, then D = D1; if D1 = D2, then D = D1 = D2. The radial width D0 of the connection between the first frame 111 and the second frame 112 is the radial width of the first end 1111 and the second end 1112, or the radial width of the third end 1121 and the fourth end 1122, as shown. Figure 2 As shown, D0 satisfies: D0 < D, thus forming at least one waist-cinching structure on at least one side portion of the support frame 11. The shape of the first frame 111 can be the shape of an ellipse or rectangle with a small portion removed, or other similar shapes or variations, without limitation. The second frame 112 can also be the shape of an ellipse or rectangle with a small portion removed, such as... Figure 2 , Figure 4 and Figure 5 As shown, other similar shapes or variations are also possible and are not limited here. In this embodiment, the first border 111 is shaped by removing a portion of a straight line segment from one side of an ellipse, and the second border 112 is a shape that is mirror-symmetrical to the first border 111. This shape has smooth edges to avoid scratching the inner wall tissue of the aortic arch. For other shapes, various damage prevention methods in the prior art can be used to avoid scratching, which will not be elaborated here.

[0032] like Figure 2As shown, the first frame 111 includes a first end 1111 and a second end 1112, and the second frame 112 includes a third end 1121 and a fourth end 1122. The first end 1111 is connected to the third end 1121, and the second end 1112 is connected to the fourth end 1122. The radial distance between the first end 1111 and the second end 1112 is less than the maximum radial width D1 of the first frame 111, and the radial distance between the third end 1121 and the fourth end 1122 is less than the maximum radial width D2 of the second frame 112. Preferably, the support frame 11 is symmetrical about its central axis. Therefore, at the connecting portion A connecting the first end 1111 and the third end 1121 of the support frame 11, and at the connecting portion B connecting the second end 1112 and the fourth end 1122, a waist-recessed structure is formed on both sides of the support frame 11 axially relative to the other parts of the support frame 11. That is, at the connecting portions A and B of these two connections, the first frame 111 and the second frame 112 are recessed toward the interior of the support frame 11. At this time, the first end 1111 and the third end 1121 are closer to the central axis of the support frame 11 than the side portion of the support frame 11, and the second end 1112 and the fourth end 1122 are closer to the central axis of the support frame 11 than the side portion of the support frame 11. Thus, a relatively independent wing portion is formed on each of the two side portions of the first frame 111, and a relatively independent wing portion is also formed on each of the two side portions of the second frame 112. Therefore, during the process of the thrombus filter 10 being implanted into the appropriate position at the three branch vessels in the aortic arch and being released and deployed, the first frame 111 and the second frame 112 cooperate regionally to conform to the aortic arch to fix the thrombus filter 10 in the aortic arch, increasing the stability of the fixation. At the same time, the filter 12 is supported upward by its pre-shaped arc structure so that each part of the filter 12 fits against the inner wall of the three branch vessels in the aortic arch. Furthermore, since there is at least one waist-tightening structure between the first frame 111 and the second frame 112, there is at least one wing portion in the first frame 111 and at least one wing portion in the second frame 112. The two adjacent wing portions exert less influence on each other under the action of the aortic arch, so they can be adjusted freely according to the shape of the blood vessel wall, thereby adapting to the structure and size of the aortic arch in different regions. This ensures that the support frame 11 fits the aortic arch better and has better radial compliance, fitting the inner wall more tightly. This makes the thrombus filter 10 more effective in filtering thrombi and other particles or particles in the blood flow to the three branch vessels, and also reduces the possibility of leakage at the edge of the support frame 11.

[0033] The first frame 111 can be made of alloys or polymers with shape memory properties, such as nickel-titanium alloys, cobalt-chromium alloys, TPU, PTFE, PE (polyethylene), etc. The second frame 112 can also be made of alloys or polymers with shape memory properties, such as nickel-titanium alloys, cobalt-chromium alloys, TPU, PTFE, PE, etc.

[0034] The thrombus filter 10 also includes a connecting part, such as Figure 2 As shown, in this embodiment, the connecting portion is a connecting portion A between the first end 1111 and the third end 1121, and a connecting portion B between the second end 1112 and the fourth end 1122. The connecting portion connects at least the first frame 111 and the second frame 112 in series along the axial direction of the thrombus filter 10. In other embodiments, the connecting portion may also be a rotating member or other connection methods.

[0035] In this implementation, two tapered structures are formed between the first border 111 and the second border 112. In other implementations, a tapered structure may be provided only on one side of the thrombus filter 10, such as... Figure 4-5 As shown, the connecting portion A of the first end 1111 and the third end 1121 is recessed towards the interior of the support frame 11, thus forming a waist-cinching structure. While the second end 1112 and the fourth end 1122 are connected together, the connecting portion extends axially and is not recessed towards the interior of the support frame 11. Wherein, as... Figure 4-5 In the middle, the width of the border at the connection between the first border 111 and the second border 112 along the radial direction is the width of the first end 1111 and the second end 1112 along the radial direction or the width of the third end 1121 and the fourth end 1122 along the radial direction, that is, the width of the waist of its waist-cinching structure along the radial direction.

[0036] In this implementation, the first end 1111 and the second end 1112 are spaced apart, and the third end 1121 and the fourth end 1122 are also spaced apart, so that the ends of the first frame 111 and the second frame 112 on the same side are directly connected, which can prevent the possibility of leakage caused by gaps between adjacent frames. At the same time, the waist-tight structure formed gives the thrombus filter a higher degree of freedom and flexibility, which can increase the radial compliance of the thrombus filter, thereby better adapting to different structures and sizes of the aortic arch, and can also adjust the height of the support of the filter screen 12 as needed.

[0037] The proximal segment of connector 13 is hollow and tubular, while the distal segment is rod-shaped. The distal ends of the proximal segments are directly connected to the proximal ends of the distal segments. The proximal segment of connector 13 allows the distal end of the sheath core 18 to pass through it proximally and then extend distally for a distance until the distal end of the sheath core 18 is closer to the distal end of the thrombus filter 10. Figure 3 As shown, after implantation into the aortic arch, the distal segment can rest against the sheath core. In clinical applications, the thrombus filter 10 can be fixedly connected to the distal end of the sheath core 18 via the proximal segment of the connector 13. In other implementations, the thrombus filter 10 can also be fixedly connected to the sheath core via a fixing wire provided on the second frame 112.

[0038] like Figure 6-7 As shown, Figure 1 When the thrombus filter 10 shown is placed on a horizontal plane M, the vertical distance H from the highest point of the thrombus filter 10 to the horizontal plane M is greater than or equal to 0 mm and less than or equal to 100 mm. Preferably, 20 mm ≤ H ≤ 80 mm; for example, H can be 50 mm. The length L of the support frame 11 is in the range of 60 mm ≤ L ≤ 200 mm.

[0039] The width W of the support frame 11 ranges from 30mm ≤ W ≤ 100mm. When the thrombus filter is placed on the horizontal plane M, at least two ends are in contact with the horizontal plane M, while the middle part of the support frame 11 arches upward, meaning the support frame 11 is curved relative to the horizontal plane M, and the curvature d of the curvature ranges from R20 to R60. This allows the curved support frame 11 to better conform the filter mesh to the inner wall of the aortic arch after the thrombus filter 10 is released. The thrombus filter 10 with the above-described structure, made using these parameters, can cover most of the three branch vessels of the aortic arch, achieving effective embolism prevention.

[0040] To facilitate observation of the surgical procedure using DSA (Digital Subtraction Angiography) equipment, at least two contrast-enhancing elements can be installed on the thrombus filter 10. These contrast-enhancing elements can be made of materials that are visible under DSA, such as gold, platinum, platinum-iridium alloy, or other highly radiolucent materials. The specific structure or shape of the contrast-enhancing elements is not limited, as long as they can be fixed in a suitable position on the thrombus filter 10. Specifically, for example... Figure 1-2As shown, a first contrast agent 113 can be provided at the distal end of the support frame 11, and a second contrast agent 114 can be provided at the proximal end of the support frame 11. In other implementations, other contrast agents can also be provided at other locations on the thrombus filter 10, such as on the first end 1111 or its constricted portion, to help determine whether the filter screen 12 on the thrombus filter 10 effectively adheres to the inner wall of the aortic arch.

[0041] This embodiment also proposes a thrombus filtration system 100 including the aforementioned thrombus filter 10 and sheath core. The thrombus filtration system 100 further includes a delivery device 90 for compressing and delivering the aforementioned thrombus filter 10, such as... Figure 3 As shown, the delivery device 90 includes a sheath core 18 and a sheath tube (not shown in the figure). The aforementioned thrombus filter 10 possesses superelasticity and shape memory properties. After being fixed to the distal end of the sheath core 18, the sheath core 18 pulls the thrombus filter 10 into the sheath tube (not shown in the figure), where it is compressed within the space between the sheath tube and the sheath core. This allows the thrombus filter 10 to be delivered into the body via the sheath tube before being released and unfolded to fit the aortic arch. When the thrombus filter 10 extends from the sheath tube, the positions of the thrombus filter 10 and the sheath core 18 relative to the three branch vessels of the aortic arch are as follows: Figure 3 As shown, the thrombus filter 10 can expand and unfold under the action of shape memory properties to form a shape like... Figure 1 The deployed state is shown. The thrombus filter 10, after deployment at the aortic arch, has the same shape as the deployed state. Figure 1 The deployed state shown is generally consistent in its natural state, but may vary slightly depending on the specific implantation location in the aortic arch. Unless otherwise specified, the above descriptions of the thrombus filter 10 describe its characteristics in the deployed state.

[0042] Before the procedure, one end of the thrombus filter 10 needs to be fixed at a suitable position at the distal end of the sheath core 18. This can be done by fixing the proximal end of the thrombus filter 10 to the sheath core 18 while leaving the distal end unfixed, or by fixing the distal end of the thrombus filter 10 to the sheath core 18 while leaving the proximal end unfixed. The following will describe the process in detail using the example of fixing the proximal end of the thrombus filter 10 to the sheath core. The proximal end of the sheath core is inserted into the distal end of the sheath tube and then exits through the lumen of the sheath tube until the thrombus filter 10 is pulled into the distal lumen of the sheath tube. This causes the thrombus filter 10 to be radially compressed and axially elongated, thus being housed within the distal end of the sheath tube in a compressed state.

[0043] During the procedure, a puncture is made in the femoral artery on one side of the human or animal body, and a guidewire is then inserted to establish an intra-body delivery channel. Once the guidewire reaches the predetermined position, the sheath containing the thrombus filter 10 is delivered along the guidewire channel to the aortic arch region. At this point, using a DSA device, the relative positions of the thrombus filter 10 and the three branch vessels of the aortic arch are determined based on the positions of the multiple contrast elements on the thrombus filter 10. When the DSA device shows that the first contrast element 113 and the second contrast element 114 on the thrombus filter 10 are respectively located at both ends of the three branch vessel regions of the aortic arch, the sheath core is kept still, and the sheath is slowly withdrawn to gradually release the thrombus filter 10 from the sheath until the entire thrombus filter 10 extends completely from the distal end of the sheath and expands to cover the openings of the three branch vessels of the aortic arch. Afterwards, a pigtail catheter is used to... After the femoral artery enters and passes through the aortic arch, angiography is performed at the location of the calcified aortic valve. The aortic valve replacement sheath is then inserted into the body through puncture of the contralateral femoral artery until it reaches the aortic valve for valve replacement. During the replacement, detached calcified tissue, emboli, and other particles or microparticles move towards the aortic arch with the blood flow. Because the thrombus filter 10 has formed a tight filtration mechanism at the openings of the three branch vessels of the aortic arch, emboli, calcified tissue, and other floating objects are deflected by the thrombus filter 10 to the descending aorta, thus preventing these floating objects from flowing to the brain through the three branch vessels. After the aortic valve replacement is completed, the aortic valve replacement sheath is withdrawn. Then, the sheath of the thrombus filtration system is pushed distally to compress the thrombus filter 10 and contain it within the distal end of the sheath. Finally, the thrombus filter 10 is withdrawn from the body along with the sheath, thus completing the surgery.

[0044] Example 2

[0045] Example 2 presents another thrombus filter and its thrombus filtration system. The features of the thrombus filter 20 in Example 2 that are the same as or can be reused from the thrombus filter 10 in Example 1 will not be described again here. The main difference is that, in the thrombus filter 20 of Example 2, such as... Figure 8-12 As shown, the support frame 21 also includes at least one third frame 213 located along its axial direction between the first frame 211 and the second frame 212, the first frame 211 and the second frame 212 being connected by one or more third frames 213.

[0046] In one implementation, such as Figure 8-11As shown, the support frame 21 includes a first frame 211, a third frame 213, and a second frame 212 arranged sequentially from near to far along its axial direction. The third frame 213 includes a fifth end 2131 and a sixth end 2132 located at its near end and correspondingly arranged, and a seventh end 2133 and an eighth end 2134 located at its far end and correspondingly arranged. The first end 2111 is connected to the fifth end 2131, the second end 2112 is connected to the sixth end 2132, the third end 2121 is connected to the seventh end 2133, and the fourth end 2122 is connected to the eighth end 2134. The radial distance between the fifth end 2131 and the sixth end 2132 is less than the maximum radial width of the third frame 213, and the radial distance between the seventh end 2133 and the eighth end 2134 is less than the maximum radial width of the third frame 213. Thus, one or two waist-recessed structures can be formed between the first frame 211 and the third frame 213, and one or two waist-recessed structures can be formed between the third frame 213 and the second frame 212. Specifically, as Figure 9 As shown, when both the fifth end 2131 and the sixth end 2132 are closer to the central axis of the support frame 21 than the side portion of their corresponding support frame 21, two waist-cinching structures can be formed between the first frame 211 and the third frame 213; when only one of the fifth end 2131 and the sixth end 2132 is closer to the central axis of the support frame 21 than the side portion of its corresponding support frame 21, one waist-cinching structure is formed between the first frame 211 and the third frame 213. Similarly, when both the seventh end 2133 and the eighth end 2134 are closer to the central axis of the support frame 21 than the side portion of their corresponding support frame 21, two waist-cinching structures can be formed between the second frame 212 and the third frame 213; when only one of the seventh end 2133 and the eighth end 2134 is closer to the central axis of the support frame 21 than the side portion of its corresponding support frame 21, one waist-cinching structure is formed between the second frame 212 and the third frame 213. Taking the first frame 211 and the third frame 213 as examples, forming two waist-cinching structures between them, compared to forming a single waist-cinching structure, allows each of the two side portions to adapt more flexibly to the structure and compression degree of the aortic arch. This makes the support frame 21 more firmly fixed at the aortic arch. In addition, the force exerted by the aortic arch on the two side portions can be transmitted to the waist-cinching structures, thereby promoting the cooperation of the two opposing waist-cinching structures to lift the filter 22 upward, enhancing the tight fit between the filter 22 and the inner wall of the three branch vessels of the aortic arch, and increasing the stability of the fixation. The effect of the two waist-cinching structures formed between the second frame 212 and the third frame 213 is the same, and will not be described again here.

[0047] In other implementations, the radial distance between the fifth end 2131 and the sixth end 2132 may be less than the maximum radial width of the third frame 213, thereby forming one or two waist-tightening structures between the first frame 211 and the third frame 213 to enhance the adaptability and stability of the thrombus filter 20 after implantation into the aortic arch or other blood vessels.

[0048] In this implementation, such as Figure 9 As shown, the first end 2111 and the second end 2112 are spaced apart, as are the fifth end 2131 and the sixth end 2132. This "spaced apart" means that the two ends are not directly connected, but rather disconnected or have gaps. The third end 2121 and the fourth end 2122 are also spaced apart, as are the seventh end 2133 and the eighth end 2134. The adjacent ends of the first frame 211, the second frame 212, and the third frame 213 are directly connected on the same side, preventing gaps between adjacent frames that could lead to leakage. Simultaneously, the resulting tapered structure gives the first frame 211, the second frame 212, and the third frame 213 greater freedom and flexibility, increasing the radial compliance of the thrombus filter. This allows for better adaptation to different structures and sizes of the aortic arch, and also allows for adjustment of the height supporting the filter 22 as needed.

[0049] In another implementation, such as Figure 12As shown, the support frame 21 includes a first frame 211, a proximal third frame 213a, a distal third frame 213b, and a second frame 212 arranged sequentially from near to far along its axial direction. That is, the support frame 21 includes two third frames 213 connected in series along its axial direction. The proximal third frame 213a includes a fifth end 2131 and a sixth end 2132 located at its proximal end and correspondingly arranged, and a seventh end 2133 and an eighth end 2134 located at its distal end and correspondingly arranged. The distal third frame 213b includes a ninth end 2135 and a tenth end 2136 located at its proximal end and correspondingly arranged, and an eleventh end 2137 and a twelfth end 2138 located at its distal end and correspondingly arranged. The first end 2111 is connected to the fifth end 2131, the second end 2112 is connected to the sixth end 2132, the seventh end 2133 is connected to the ninth end 2135, the eighth end 2134 is connected to the tenth end 2136, the eleventh end 2137 is connected to the third end 2121, and the twelfth end 2138 is connected to the fourth end 2122. The radial distance between the fifth end 2131 and the sixth end 2132 is less than the maximum radial width of the near-end third border 213a. The radial distance between the ninth end 2135 and the tenth end 2136 is less than the maximum radial width of the far-end third border 213b. The radial distance between the seventh end 2133 and the eighth end 2134 is less than the maximum radial width of the near-end third border 213a. The radial distance between the eleventh end 2137 and the twelfth end 2138 is less than the maximum radial width of the far-end third border 213b. Therefore, one or two waist-slimming structures can be formed between the first border 211 and the near-end third border 213a, between the near-end third border 213a and the far-end third border 213b, and between the far-end third border 213b and the second border 212.

[0050] In other implementations, when the support frame 21 includes two or more third frame borders 213, all the third frame borders 213 are connected in pairs along the axial direction of the thrombus filter 20, so as to adapt to the curvature of different parts of the aortic arch, achieving better adaptability and fixation. The different third frame borders 213 have the same or similar shapes, and their sizes can be the same or different. The waist-tightening between two adjacent third frame borders 213 is similar to that in the aforementioned implementations, and will not be described again here.

[0051] The third frame 213 can be made of alloys or polymers with shape memory properties, such as nickel-titanium alloys, cobalt-chromium alloys, TPU, PTFE, PE, etc.

[0052] Example 3

[0053] Example 3 presents another thrombus filter and its thrombus filtration system. Features that are identical or reusable to those in the thrombus filter of Example 3 and the thrombus filter of Example 2 will not be repeated here. The main difference lies in that, in the thrombus filter of Example 3, such as... Figure 13-14 As shown, the support frame 31 includes a first frame 311 and a second frame 312. The first end 3111 of the first frame 311 is connected to the third end 3121 of the second frame 312 by a rotating member 34. The second end 3112 of the first frame 311 is connected to the fourth end 3122 of the second frame 312 by a rotating member 34. In this embodiment, the rotating member 34 includes a rotating shaft 341 that passes radially through the first end 3111 and the third end 3121 (or the second end 3112 and the fourth end 3122) and ball heads 342 disposed at both ends of the rotating shaft. Each end is provided with a hole (not shown in the figure) in the radial direction for the rotating shaft 341 to pass through, thereby connecting the first frame 311 and the second frame 312 together axially. The first frame 311 can rotate relative to the second frame 312 along the rotating shaft 341 under the action of external force. The rotating element 34 allows the first frame 311 to rotate relative to the second frame 312, thereby giving the thrombus filter greater freedom and flexibility to better adapt to different structures and sizes of the aortic arch or other blood vessels.

[0054] Specifically, such as Figure 13 As shown, the thrombus filter includes a first frame 311 and a second frame 312. At least one waist structure is provided between the first frame 311 and the second frame 312, thereby forming a relatively free wing portion that can be adjusted freely and flexibly, increasing the radial compliance of the thrombus filter. The waist structure allows the thrombus filter to regionally adapt to the structure and size of the aortic arch, ensuring that the support frame is more firmly fixed in the aortic arch and fits the inner wall more tightly. This makes the thrombus filter more effectively filter thrombi and other particles or particles in the blood flow to the three branch vessels, and also reduces the possibility of leakage at the edge of the support frame.

[0055] The ends of the two side frames of the support frame 31 are connected by a rotating member 34. The first side frame 311 can rotate relative to the second side frame 312 under the pressure of the blood vessel wall shape structure, so that the thrombus filter adapts to the structure of the aortic arch, increasing the axial compliance of the thrombus filter, and allowing each side frame to deform independently to adapt to the aortic arch wall and fit more tightly.

[0056] Example 4

[0057] Example 4 presents another thrombus filter and its thrombus filtration system. The features of the thrombus filter in Example 4 that are identical or can be reused from the thrombus filter 10 in Example 1 will not be repeated here. The main difference is that, in the thrombus filter of Example 4, such as... Figure 15 As shown, the first frame 411 and the second frame 412 of the support frame 41 partially overlap to form an overlapping area 47. The setting of the overlapping area 47 can better control the shape and size of the waist-cinching structure to reduce edge leakage in the area where the waist-cinching structure is located.

[0058] like Figure 15 As shown, the maximum radial width of the first border 411 is D1, and the maximum radial width of the second border 412 is D2. D is the smaller of D1 and D2; that is, if D1 > D2, then D = D2; if D1 < D2, then D = D1; if D1 = D2, then D = D1 = D2. The radial width of the border at the junction of the first border 411 and the second border 412 is the radial width D0 of the intersection point of the outer sides of the two overlapping areas. In this embodiment, D1 = D2, then D = D1 = D2, and D0 satisfies: D0 < D1.

[0059] This invention provides a thrombus filter with at least one concave structure formed radially between two adjacent frame sides. That is, a portion of at least one side of the support frame is recessed towards the interior of the support frame, so that the axial sides of the two adjacent frame sides can be adjusted relatively flexibly and freely, thereby regionally adapting to the structure and size of the aortic arch, resulting in higher compliance. This ensures that the support frame is more firmly fixed within the aortic arch and fits more tightly against the inner wall, making the thrombus filter more effective at filtering thrombi and other particles or microparticles in the blood flow to the three branch vessels, and also reducing the possibility of leakage at the edge of the support frame.

[0060] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0061] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A thrombus filter, comprising a support frame and at least one filter screen covering the support frame, characterized in that, The support frame includes at least two adjacent side frames arranged along its axial direction from near to far. The surface formed by the support frame is an arc-shaped surface. Among the two adjacent side frames, the maximum radial width of one side frame is D1, and the maximum radial width of the other side frame is D2. D is defined as the smaller value between D1 and D2. The width of the side frame connected to the two side frames along the radial direction at the connection point is D0. D0 satisfies: D0 < D. Thus, at least one waist-recessed structure is formed on at least one side portion of the support frame. The waist-recessed structure makes the support frame no longer a whole regular closed loop frame, but a regional support frame formed by the waist-recessed structure. The side edges of the side frames forming the waist-recessed structure can be adjusted relatively flexibly. One of the frame frames includes a first end and a second end, and the other frame frame includes a third end and a fourth end, the first end being connected to the third end, the second end being connected to the fourth end, the first end being connected to the third end by a rotating member, and the second end being connected to the fourth end by a rotating member, the rotating member passing radially through each end such that at least one side portion of the two adjacent frame frames forms a wing portion that can swing relatively independently.

2. The thrombus filter according to claim 1, characterized in that, The radial distance between the first end and the second end is less than the maximum radial width of the corresponding frame, and the radial distance between the third end and the fourth end is less than the maximum radial width of the corresponding frame.

3. The thrombus filter according to claim 2, characterized in that, Both the first end and the third end are closer to the central axis of the support frame than the side portion of the support frame.

4. The thrombus filter according to claim 2, characterized in that, Both the second end and the fourth end are closer to the central axis of the support frame than the side portion of the support frame.

5. The thrombus filter according to claim 2, characterized in that, The first end and the second end are spaced apart.

6. The thrombus filter according to claim 1, characterized in that, The support frame is symmetrical about its central axis.

7. The thrombus filter according to claim 1, characterized in that, The rotating component includes a rotating shaft and ball heads disposed at both ends of the rotating shaft.

8. The thrombus filter according to claim 1, characterized in that, The support frame includes at least three adjacent frame sides.

9. A thrombus filtration system, characterized in that, It includes a thrombus filter as described in any one of claims 1-8 and a delivery device for delivering the thrombus filter.

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