Thrombus collecting device for thrombus extraction in superior mesenteric artery cavity and manufacturing method
By designing a thrombus collection device with a supporting framework and a flexible filter, the problems of thrombus detachment and vascular damage in existing technologies have been solved, achieving efficient and safe removal of thrombi from the superior mesenteric artery, and is applicable to various lesion types.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-03-10
- Publication Date
- 2026-04-07
AI Technical Summary
Existing superior mesenteric artery endovascular thrombectomy devices are prone to thrombus dislodgement and vascular damage during operation, making them unsuitable for all patients. In particular, when the lesion is extensive, multiple operations are required, and there is a risk of iatrogenic vascular intimal damage.
A thrombus collection device comprising a supporting skeleton and a flexible filter was designed. The supporting skeleton is made of nickel-titanium alloy, and the flexible filter is deformable. Through the cooperation of the blade deformation component and the traction catheter, efficient collection of thrombi is achieved. At the same time, a delivery sheath and a retrieval sheath are used to wrap the supporting skeleton to reduce vascular damage.
It achieves complete removal of thrombi, reduces the risk of vascular damage and embolus dislodgement, simplifies the procedure, and reduces the difficulty of surgery and the risk of radiation exposure to patients.
Smart Images
Figure CN121796003A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of medical device technology, and in particular to a thrombus collection device and manufacturing method for endovascular thrombectomy of the superior mesenteric artery. Background Technology
[0002] The statements in this section are merely background information related to the present invention and do not necessarily constitute prior art.
[0003] Superior mesenteric artery thrombotic disorders are a major cause of acute intestinal ischemia, primarily including two types: superior mesenteric artery embolism and mesenteric artery thrombosis. These diseases often have a rapid onset and are extremely dangerous; if blood supply is not restored in time, they can progress to intestinal necrosis, sepsis, and multiple organ failure, resulting in a high mortality rate. For these diseases, if intestinal necrosis has already occurred, the affected intestinal segment needs to be removed, and if necessary, combined with superior mesenteric artery thrombectomy; if intestinal necrosis has not occurred, surgery is needed to restore blood supply to the superior mesenteric artery to prevent intestinal necrosis.
[0004] Currently, conventional superior mesenteric artery thrombectomy requires open surgery, which is highly invasive and carries common complications such as intestinal adhesions, intestinal obstruction, and incision infection. Endovascular surgeries for superior mesenteric artery thrombotic diseases are now available clinically, including sheath aspiration, mechanical thrombectomy, stent thrombectomy, catheter-directed thrombolysis, and stent placement. These endovascular procedures are typically performed under image guidance via a peripheral arterial approach (such as the femoral or radial artery) to deliver instruments or stents into the superior mesenteric artery, resulting in less trauma compared to open surgery. Endovascular surgery aims to rapidly remove thrombi and restore intestinal perfusion, thereby avoiding open surgery and its associated complications, and is particularly suitable for elderly patients or those with multiple underlying diseases.
[0005] However, these endovascular surgical methods have different indications, each with its own advantages and disadvantages, and cannot meet the needs of all patients. Guided sheath (or guided catheter) aspiration is mostly used for lesions with small thrombi. If the lesion is large, repeated aspiration is often required, resulting in poor efficacy; there is also a risk of thrombus dislodgement during catheter removal. Mechanical thrombectomy is a common surgical method for peripheral arterial thrombosis, but experimental experience with the superior mesenteric artery is limited; this method is only suitable for arteries with a diameter of 3mm or more, and therefore applicable to segmental lesions; thrombus dislodgement is one of its main complications, and can also cause distal arterial embolism. Stent thrombectomy is currently mainly used for carotid and intracranial arterial thrombotic diseases, with limited experience in the superior mesenteric artery, possibly related to the poor efficacy of stent thrombectomy. Catheter thrombolysis is generally suitable for patients with relatively good cardiopulmonary conditions, but not for patients with heart failure or other diseases; this method requires prolonged bed rest and immobilization, generally 24-72 hours, with slow onset and long duration, which is not conducive to rapid restoration of blood supply, and carries the risk of intestinal necrosis due to increased intestinal ischemia during thrombolysis. After implantation of a endovascular stent graft or bare-metal stent in the superior mesenteric artery, there is a risk of thrombus dislodgement and travel to the distal artery. Additionally, thrombi can enter the bare-metal stent through the mesh, leading to stent occlusion. Therefore, this method is not the first-line procedure and is generally used when guide sheath aspiration or other methods are ineffective. Thus, currently, no single endovascular procedure is suitable for all patients with different lesions.
[0006] The application of existing technologies in endovascular thrombectomy of the mesenteric artery still has shortcomings: when inserting a guide sheath via femoral artery puncture, the mesenteric artery forms an acute angle with the abdominal aorta below the opening, which is not conducive to the smooth entry of the catheter sheath into the superior mesenteric artery, and can easily cause iatrogenic vascular intimal damage, which can lead to complications such as vasospasm and aortic dissection, increasing the complexity and risks of subsequent treatment.
[0007] In summary, existing thrombectomy devices or instruments require repeated or multiple operations, and the thrombus is prone to dislodging when moving in the blood vessel after thrombectomy, increasing the difficulty of the operation. Moreover, they can cause certain damage to the blood vessel during the insertion process. Summary of the Invention
[0008] In view of the shortcomings of the existing technology, the purpose of this invention is to provide a thrombus collection device for endovascular thrombectomy of the superior mesenteric artery, which can efficiently and completely remove thrombi while minimizing vascular damage and fragment embolism.
[0009] To achieve the above objectives, the present invention is implemented through the following technical solution: A thrombus collection device for endovascular thrombectomy of the superior mesenteric artery includes a support frame placed outside a flexible filter to support the filter. The flexible filter is deformable and has one open end. When unfolded, the flexible filter forms a cavity inside to accommodate the thrombus. The support frame is elastic and has shape memory capabilities. One end of the support frame is connected to a support catheter, and the other end of the support frame extends beyond the flexible filter. Multiple leaf-shaped deformable components are provided at the end of the support frame extending beyond the flexible filter. Each leaf-shaped deformable component is connected to a traction catheter via a traction wire. The traction catheter passes through the support catheter. By operating the traction catheter, the leaf-shaped deformable components bend towards the central axis of the flexible filter to close the flexible filter. The thrombectomy catheter with the thrombus moves relative to the support frame so that the thrombus falls into the flexible filter.
[0010] The thrombus collection device for endovascular thrombectomy of the superior mesenteric artery, as described above, further includes a delivery sheath and a retrieval sheath. The delivery sheath and retrieval sheath are movable along the axial direction of the supporting catheter. The supporting skeleton is a hollow structure made of nickel-titanium alloy. The delivery sheath and retrieval sheath can wrap around the deformed supporting skeleton. The inner diameter of the delivery sheath and retrieval sheath is smaller than the diameter of the flexible filter when it is stretched. Because the supporting skeleton is elastic, when the retrieval sheath moves quickly to the outside of the supporting skeleton, it squeezes the supporting skeleton, causing the supporting skeleton to deform. This allows the retrieval sheath to wrap around the thrombus collection device containing the thrombus. The retrieval sheath drives the entire device to move, effectively preventing the thrombus from slipping out.
[0011] The thrombus collection device for endovascular thrombectomy of the superior mesenteric artery, as described above, has a flexible filter made of a biocompatible thin film material, with multiple micropores on the circumferential surface of the flexible filter, the micropores having a diameter of 100-120 micrometers.
[0012] The thrombus collection device for endovascular thrombectomy of the superior mesenteric artery as described above, wherein the flexible filter includes a first filter and a second filter, the first filter and the second filter are connected, and when the flexible filter is unfolded, the first filter is a cylindrical filter and the second filter is a conical filter; The end of the first filter screen furthest from the second filter screen is designed with a wavy structure to avoid damaging the blood vessel wall. A skirt structure is provided at the wavy structure to support the flexible filter screen. The skirt structure is made of nickel-titanium shape memory alloy wire.
[0013] The thrombus collection device for endovascular thrombectomy of the superior mesenteric artery as described above includes a supporting frame comprising a first section, a second section, and a third section connected in sequence. The first section is conical, the second section is cylindrical, and the third section is the blade deformation assembly. The first section is connected to the supporting conduit via a connector. The skirt structure is disposed near the end of the second section away from the first section, and the skirt structure does not extend beyond the second section.
[0014] The thrombus collection device for endovascular thrombectomy of the superior mesenteric artery as described above includes a first section comprising multiple first connectors and a second section comprising multiple second connectors. One end of each first connector is connected to the connector described above. Each second connector includes multiple long sections with openwork. Adjacent long sections are connected by a V-shaped member. Both ends of the second connector are pointed, and one pointed end of the second connector is connected to the first connector.
[0015] As described above, a thrombus collection device for endovascular thrombectomy of the superior mesenteric artery includes a blade deformation assembly comprising a central connector with an opening in the middle section. One end of the pull wire is connected to the opening. Bending members are respectively provided on both sides of the central connector, with one end of the bending member connected to one end of the central connector. The width of the blade deformation assembly away from the second segment is less than the width of the middle section of the blade deformation assembly to ensure the closing effect of the blade deformation assembly. The length of the bending member is less than the length of the central connector.
[0016] The thrombus collection device for endovascular thrombectomy of the superior mesenteric artery, as described above, uses a traction wire made of a nickel-titanium alloy wire. All traction wires are woven to ensure rotation.
[0017] Secondly, the present invention also provides a method for manufacturing a thrombus collection device for endovascular thrombectomy of the superior mesenteric artery, comprising the following: Fabrication of the support frame: The raw material of the support frame is cut to form a cylindrical structure. The support frame is then fitted onto the outside of the inner cylinder of the mold. An outer cylinder of the mold is set on the outside of the support frame. The shape of the inner cylinder of the mold is the same as that of the flexible filter screen. The assembled support frame and the mold are placed together in a heat treatment furnace and kept at the set temperature for 10-30 minutes, followed by quenching. Making flexible filter screens: The flexible filter is placed inside the support frame, and the blade deformation component in the support frame extends beyond the flexible filter.
[0018] The method for manufacturing a thrombus collection device for endovascular thrombectomy of the superior mesenteric artery as described above, wherein the manufacturing of the flexible filter includes the following steps: A flexible filter screen is made by selecting a biocompatible thin film material and forming multiple micropores by circumferential perforation of the biocompatible thin film material. One end of the flexible filter screen is made into a wave structure. The trained nickel-titanium shape memory alloy wires are connected to the wave structure of the flexible filter to form a skirt structure.
[0019] The beneficial effects of the present invention are as follows: 1) The thrombus collection device provided by this invention has a reasonable structure. The thrombus collection device can be placed in the abdominal aorta and cooperate with the thrombectomy catheter. The supporting skeleton supports the flexible filter. One end of the flexible filter is open. Multiple leaf deformation components are set at the end of the supporting skeleton that extends beyond the flexible filter. Each leaf deformation component is connected to the traction catheter through the traction wire. The traction catheter passes through the supporting catheter and places the thrombus in the unfolded flexible filter. By operating the traction catheter, the leaf deformation components bend towards the central axis of the flexible filter to close the flexible filter. The thrombectomy catheter with the thrombus moves relative to the supporting skeleton so that the thrombus falls into the flexible filter, thus realizing the collection of the thrombus. The leaf deformation components close the flexible filter, thus avoiding problems such as thrombus dislodgement. The whole device can perform thrombectomy in the superior mesenteric artery. The operation is simple and effective. It does not require multiple operations and reduces damage to blood vessels.
[0020] 2) The thrombus collection device of the present invention is also provided with a recovery sheath, which can wrap around the deformed support frame. Because the support frame is elastic, when the recovery sheath moves quickly to the outside of the support frame, it squeezes the support frame and causes the support frame to deform, thereby allowing the recovery sheath to wrap around the thrombus collection device with the thrombus. The recovery sheath drives the whole device to move, which fully avoids the slippage of the thrombus.
[0021] 3) In this invention, a flexible filter is provided. The flexible filter is deformable. The end of the first filter away from the second filter is set with a wave structure to avoid damaging the blood vessel wall. A skirt structure is set at the wave structure to support the flexible filter. The skirt structure is made of nickel-titanium shape memory alloy wire.
[0022] 4) The blade deformation component in this invention is reasonably set. The blade deformation component includes a central connector, which is connected to the drawing wire. Bending components are respectively set on both sides of the central connector. One end of the bending component is connected to one end of the central connector. The width of the blade deformation component away from the second section is less than the width of the middle section of the blade deformation component to ensure the closing effect of the blade deformation component. Attached Figure Description
[0023] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.
[0024] Figure 1 This is a schematic diagram of the thrombus collection device for endovascular thrombectomy of the superior mesenteric artery according to one or more embodiments of the present invention, in the open working state.
[0025] Figure 2 This is a schematic diagram of a thrombus collection device for endovascular thrombectomy of the superior mesenteric artery according to one or more embodiments of the present invention.
[0026] Figure 3 This is a partially enlarged view of a thrombus collection device for endovascular thrombectomy of the superior mesenteric artery according to one or more embodiments of the present invention.
[0027] Figure 4 This is an enlarged view of the blade deformation assembly of a thrombus collection device for endovascular thrombectomy of the superior mesenteric artery according to one or more embodiments of the present invention.
[0028] Figure 5 This is a schematic diagram of a flexible filter screen of a thrombus collection device for endovascular thrombectomy of the superior mesenteric artery according to one or more embodiments of the present invention.
[0029] Figure 6(a) is a schematic diagram of the thrombus collection device for endovascular thrombectomy of the superior mesenteric artery according to one or more embodiments of the present invention, in its closed working state including a flexible filter.
[0030] Figure 6(b) is a schematic diagram of the thrombus collection device for intraluminal thrombectomy of the superior mesenteric artery according to one or more embodiments of the present invention in its closed working state.
[0031] Figure 7(a) is a schematic diagram of the support frame deployed in a thrombus collection device for endovascular thrombectomy of the superior mesenteric artery according to one or more embodiments of the present invention.
[0032] Figure 7(b) is a schematic diagram of the mold set inside the support frame of a thrombus collection device for endovascular thrombectomy of the superior mesenteric artery according to one or more embodiments of the present invention.
[0033] Figure 8(a) is a schematic diagram of establishing a pathway via the brachial artery and inserting a thrombectomy catheter during an endovascular thrombectomy of the superior mesenteric artery according to one or more embodiments of the present invention.
[0034] Figure 8(b) is a schematic diagram of the thrombectomy catheter passing through the thrombus to reach the distal end during an endovascular thrombectomy of the superior mesenteric artery according to one or more embodiments of the present invention.
[0035] Figure 8(c) is a schematic diagram of establishing a pathway via the femoral artery during an endovascular thrombectomy of the superior mesenteric artery according to one or more embodiments of the present invention.
[0036] Figure 8(d) is a schematic diagram of a superior mesenteric artery endovascular thrombectomy procedure according to one or more embodiments of the present invention, in which a delivery sheath is introduced via the femoral artery and a thrombus collection device is inserted.
[0037] Figure 8(e) is a schematic diagram of a thrombus collection device for endovascular thrombectomy of the superior mesenteric artery according to one or more embodiments of the present invention, with the device extended at the abdominal aorta.
[0038] Figure 8(f) is a schematic diagram of the balloon at the end of the thrombectomy catheter being injected with an appropriate amount of diluted contrast agent and entering the inflated state during an endovascular thrombectomy of the superior mesenteric artery according to one or more embodiments of the present invention.
[0039] Figure 8(g) is a schematic diagram of pulling the thrombectomy catheter to the vicinity of the abdominal aorta during an endovascular thrombectomy of the superior mesenteric artery according to one or more embodiments of the present invention.
[0040] Figure 8(h) is a schematic diagram of pulling the thrombectomy catheter upstream of the thrombus collection device during an endovascular thrombectomy of the superior mesenteric artery according to one or more embodiments of the present invention.
[0041] Figure 8(i) is a schematic diagram of a thrombectomy procedure for superior mesenteric artery according to one or more embodiments of the present invention, in which the thrombectomy catheter and the thrombus are jointly inserted into the thrombus collection device.
[0042] Figure 8(j) is a supplementary view of the thrombus collection device in the scenario of Figure 8(i) under the filter fluoroscopic state during an endovascular thrombectomy of the superior mesenteric artery according to one or more embodiments of the present invention.
[0043] Figure 8(k) is a schematic diagram of the thrombus collection device blades closing during an endovascular thrombectomy of the superior mesenteric artery according to one or more embodiments of the present invention.
[0044] Figure 8(l) is a schematic diagram of the thrombus collection device in which the traction alloy wire is embedded in the thrombus during an endovascular thrombectomy of the superior mesenteric artery according to one or more embodiments of the present invention.
[0045] Figure 8(m) is a schematic diagram of the thrombus collection device in the scenario of Figure 8(l) under thrombus fluoroscopy in a superior mesenteric artery thrombectomy according to one or more embodiments of the present invention, in which the alloy wire is pulled into the thrombus in a thrombus collection device.
[0046] Figure 8(n) is a schematic diagram of the thrombectomy catheter being detached from the thrombus collection device during an endovascular thrombectomy of the superior mesenteric artery according to one or more embodiments of the present invention.
[0047] Figure 8(o) is a schematic diagram of the thrombus collection device being retrieved into a recovery sheath during an endovascular thrombectomy of the superior mesenteric artery according to one or more embodiments of the present invention.
[0048] Figure 8(p) is a schematic diagram of the complete collection of thrombus in the thrombus collection device into the recovery sheath during an endovascular thrombectomy of the superior mesenteric artery according to one or more embodiments of the present invention.
[0049] The diagram exaggerates the spacing or dimensions between parts to show their positions; the diagram is for illustrative purposes only.
[0050] Wherein: 1-Flexible filter, 101-Skirt structure, 102-Micropores, 103-First filter, 104-Second filter, 2-Supporting skeleton, 201-First section, 202-Second section, 203-Leaf deformation assembly, 204-First connector, 205-Second connector, 206-V-shaped component, 207-Middle connector, 208-Bending component, 3-Connector, 4-Supporting catheter, 5-Pull wire, 6-Pull catheter, 7-Mold outer cylinder (schematic diagram is transparent), 8-Mold inner cylinder, 9-Thrombectomy catheter, 10-Guide wire, 11-Thrombus, 12-Delivery sheath, 13-Recovery sheath. Detailed Implementation
[0051] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the invention. Unless otherwise specified, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.
[0052] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, unless otherwise expressly indicated by the invention, the singular form is also intended to include the plural form. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof. As described in the background section, existing thrombectomy devices or apparatuses suffer from problems such as low efficiency, easy thrombus dislodgement, and damage to blood vessels during the thrombectomy process. In order to solve the above technical problems, this invention proposes a thrombus collection device for endovascular thrombectomy of the superior mesenteric artery.
[0053] Example 1 In a typical embodiment of the present invention, reference is made to Figure 1 , Figure 2 and Figure 3As shown, a thrombus collection device for endovascular thrombectomy of the superior mesenteric artery includes a supporting frame 2, a flexible filter 1, a skirt structure 101, and a blade deformation assembly 203. The flexible filter 1 is deformable, and when unfolded, it forms an internal cavity to accommodate the thrombus. The supporting frame 2 is placed circumferentially around the flexible filter 1 and is made of a superelastic nickel-titanium alloy. Utilizing the superelastic properties and shape memory capabilities of the nickel-titanium alloy, it can drive the shape memory alloy to deform the flexible filter 1 at a set temperature, causing the flexible filter 1 to form a cylindrical reconstructed filter. The overall deformation is proactive. One end of the supporting frame 2 is connected to a supporting conduit 4, through which the supporting frame 2 and the flexible filter are connected. The mesh 1 is inserted into the blood vessel. The other end of the supporting skeleton 2 extends beyond the flexible filter 1. Multiple leaf deformation components 203 are provided at the end of the supporting skeleton 2 that extends beyond the flexible filter 1. Each leaf deformation component 203 is connected to the traction catheter 6 through the traction wire 5. The traction catheter 6 passes through the supporting catheter 4. The traction catheter 6 can be pulled and rotated. Through external operation, the traction catheter 6 can pull the leaf deformation components 203 through the traction wire 5. By operating the traction catheter 6, the leaf deformation components 203 are bent towards the central axis of the flexible filter 1 to close the flexible filter 1. The thrombectomy catheter 9 with thrombus 11 moves relative to the supporting skeleton 2 so that the thrombus 11 falls into the flexible filter 1. It should be explained that the support frame 2 is made of existing superelastic nickel-titanium alloy material. The liquid at a set temperature can cause the shape memory alloy ribbon to deform the flexible filter 1 so that it forms a conical reconstructed shape. The support frame 2 has a small diameter at room temperature outside the body. When the support frame 2 is at body temperature, it can automatically recover to the shape after training, that is, the diameter increases, so that it can fit tightly against the blood vessel wall. That is, the support frame 2 drives the flexible filter 1 to open to accommodate the thrombus 11.
[0054] It should be noted that the thrombus collection device also includes a delivery sheath 12 and a retrieval sheath 13. The delivery sheath 12 and the retrieval sheath 13 can be made of plastic or other materials. Both the delivery sheath 12 and the retrieval sheath 13 are tubular structures. Under the action of external force, the delivery sheath 12 and the retrieval sheath 13 can move along the axial direction of the support catheter 4. The support skeleton 2 is a hollow structure. The delivery sheath 12 and the retrieval sheath 13 can wrap the support skeleton 2 with a smaller diameter after deformation. The inner diameter of the delivery sheath 12 and the retrieval sheath 13 is smaller than the diameter of the flexible filter 1 when it is stretched. The delivery sheath 12 is used to deliver the support skeleton 2 and the flexible filter 1 into the blood vessel. Because the support skeleton 2 is elastic, when the retrieval sheath 13 moves quickly to the outside of the support skeleton 2, it squeezes the support skeleton 2, causing the support skeleton 2 to deform and the diameter of the support skeleton 2 to become smaller. This allows the retrieval sheath 13 to wrap the thrombus collection device with the thrombus 11. The retrieval sheath 13 drives the whole device to move, which fully avoids the slippage of the thrombus. The flexible filter wrapped with the thrombus 11 is taken out of the body through the retrieval sheath 13.
[0055] It is easy to understand that the flexible filter 1 has uniformly perforated circumferential surfaces, and the holes are all micropores 102. The size of the pores ensures normal blood flow and can block detached emboli.
[0056] Specifically, the flexible filter 1 uses a 50-micron polyurethane film with micropores 102 having a diameter of 100-120 microns. It is processed using a femtosecond laser to ensure a smooth cut surface and prevent edge curling. The flexible filter 1 includes a first filter 103 and a second filter 104. The first filter 103 is a cylindrical filter at the top, and the second filter 104 is a conical filter at the bottom. The first filter 103 and the second filter 104 can be prepared separately. After preparation, the first filter 103 and the second filter 104 are rolled into a cylindrical shape. (Refer to...) Figure 5 As shown, the interface between the first filter 103 and the second filter 104 is bonded with medical adhesive. The end of the first filter 103 away from the second filter 104 is designed with a wave structure. Under normal conditions, the wave structure includes multiple continuous waves.
[0057] refer to Figure 5 As shown, a skirt structure 101 is provided at the wave structure. The skirt structure 101 is a deformation-assisted functional structure. The skirt structure 101 is made of nickel-titanium shape memory alloy wire with a near-equal atomic ratio. After training, the nickel-titanium shape memory alloy wire is connected to the wave structure on the opening side of the flexible filter 1. The cross-section of the nickel-titanium shape memory alloy wire is circular. After training, the nickel-titanium shape memory alloy wire can help open the opening of the flexible filter 1 when in working state. Both the wave structure and the skirt structure 101 are arc structures, which can prevent the creases and sharp corners of the flexible filter 1 from puncturing the blood vessel wall when it is introduced. Referring to Figures 6(a) and 6(b), the support frame 2 is a hollow structure. The support frame 2 is used to support the flexible filter screen 1. The support frame 2 includes a first section 201, a second section 202 and a third section connected in sequence. The first section is a conical section, the second section is a cylindrical section and the third section is a blade deformation component 203. The first section 201 is connected to the support conduit 4 through the connector 3. The skirt structure 101 is set at the end near the second section 202 and away from the first section 201. The skirt structure 101 does not extend beyond the second section 202.
[0058] Referring to Figure 7(a), the first segment 201 of the support frame 2 includes multiple first connectors 204. The first connectors 204 are long strip structures. The first connectors 204 are bent on the side near the second segment so that multiple first connectors are assembled to form a conical structure to support the first filter 103 of the flexible filter 1. The second segment 202 includes multiple second connectors 205. One end of the first connector 204 is connected to the connector 3. The second connector 205 includes multiple long sections. The long sections are hollowed out. Adjacent long sections are connected by a V-shaped piece 206. The V-shaped piece 206 is located near the skirt structure 101. Both ends of the second connector 205 are pointed. The connection between the first filter 103 and the second filter 104 of the flexible filter 1 is close to the connection between the first segment 201 and the second segment 202. One pointed end of the second connector 205 is connected to the first connector 204.
[0059] Specifically, the blade deformation assembly 203 includes a central connector 207. The central connector 207 has an opening in its middle section, and one end of the drawing wire 5 is connected to the opening. Bending members 208 are respectively provided on both sides of the central connector 207. One end of the bending member 208 is connected to one end of the central connector 207. The width of the end of the blade deformation assembly 203 away from the second section 202 is less than the width of the middle section of the blade deformation assembly 203 so that when all the blade deformation assemblies 203 are tilted towards the central axis of the flexible filter screen 1, the narrower end of the blade deformation assembly 203 can converge the circumference of the thrombectomy guide 9 and fit as closely as possible to the thrombectomy guide 9 to ensure the closing effect of the blade deformation assembly 203, so as to facilitate the thrombectomy from the thrombectomy guide 9 and ensure the thrombectomy effect. The bending member 208 is spaced apart from the opening of the central connector 207. Because the central connector 207 is to be connected to one end of the second connector, the length of the bending member 208 is less than the length of the central connector 207.
[0060] Specifically, the traction wire 5 is made of traction alloy wire, specifically woven from nickel-titanium alloy wire. Each traction alloy wire is connected to the traction catheter 6. The connector 3 is a connecting tube. After passing through the connector 3 and the support catheter 4, the traction catheter 6 can be manually pulled and rotated externally. The five leaf deformation components 203 on the upper part of the thrombus collection device will bend and close towards the center along the pre-cut opening under the mechanical action of the traction alloy wire. After the leaf deformation components 203 close, they restrict the movement of the thrombus, thereby removing the thrombus from the thrombectomy catheter 9. In addition, the traction alloy wire can generate spin during the operation, and it will also move into the thrombus to assist in thrombus removal.
[0061] In previous endovascular treatments, when thrombectomy stents or catheters were used to grasp or aspirate thrombi, the operation directly affected the fragile thrombus itself, which could easily lead to thrombus dislodgement or blockage of the guide sheath, increasing the difficulty of the operation and the operation time. Referring to Figures 8(a), 8(b), 8(c), and 8(d), after locating the thrombus through guidewire 10, it is retrieved through thrombectomy catheter 9. The thrombus is then pulled to the wide-diameter abdominal aorta using thrombectomy catheter 9. Referring to Figures 8(e), 8(f), 8(g), and 8(h), the thrombus is then transported through guidewire 10 and thrombectomy catheter 9 to a pre-placed thrombus collection device. Referring to Figures 8(i), 8(j), 8(k), and 8(l), this device acts as a reliable "safety net," completely containing the thrombus within the abdominal aorta, fundamentally eliminating the possibility of thrombus fragments detaching to other parts of the body and improving the safety of the procedure. Referring to Figures 8(m), 8(n), 8(o), and 8(p), after the thrombus collection device completely encapsulates the thrombus, the thrombectomy catheter 9 is withdrawn. The movement of the delivery sheath 13 deforms the supporting skeleton 2, encapsulating the supporting skeleton 2 and the thrombus, thus removing the thrombus from the body.
[0062] In endovascular surgery, multiple, prolonged fluoroscopy and angiography under DSA (Digital Subtraction Angiography) are required for precise instrument positioning and thrombus removal effectiveness, leading to increased radiation dose and contrast agent usage. The thrombus collection device of this invention simplifies the thrombus retrieval path, allowing the device to be deployed directly into the aorta in a single procedure. More importantly, once the thrombus 11 is pulled into the aorta and released, its subsequent collection process is controllable, eliminating the need for repeated angiography to track minute fragments. This shortens fluoroscopy time during core procedures, reduces radiation exposure for medical staff and patients, and decreases contrast agent usage, which is particularly beneficial for patients with renal insufficiency, reducing the risk of contrast-induced nephropathy.
[0063] Example 2 This embodiment provides a method for manufacturing a thrombus collection device for endovascular thrombectomy of the superior mesenteric artery, including the following: It needs to be explained that shape memory alloy materials obtain shape memory after solid solution treatment, constrained aging, and unconstrained aging. The shape of the memory is the same as the shape of the mold used during constrained aging. This technology is applied to the fabrication of support skeletons and skirt structures.
[0064] Fabrication of the support frame: In this embodiment, the support frame 2 is made of a superelastic nickel-titanium alloy material that meets medical device standards. The nickel-titanium alloy tube is fixed on a precision machine tool and cut according to a pre-designed two-dimensional geometric pattern using a high-precision laser, as shown in Figure 7(a). After cutting, the nickel-titanium alloy sheets are joined end to end, rolled into a cylindrical shape, and welded to form a cylindrical structural component. In addition, chemical polishing is used to remove the slag and oxide layer adhering to the inside and outside of the tube after laser cutting, and the cut surface is polished to make it smooth. The polished support frame 2 is fitted onto the outside of the inner cylinder 8 of the mold, and the outer cylinder 7 of the mold is placed on the outside of the support frame 2. The inner cavity shape of the inner cylinder 8 and the outer cylinder 7 of the mold is the same as the shape of the flexible filter 1 (the ideal three-dimensional shape of the flexible filter 1 when fully expanded in the abdominal aorta), as shown in Figure 7(b). One end of the inner cylinder 8 and the outer cylinder 7 of the mold is flush with the end of the blade deformation component. Finally, the assembled support frame 2 and the mold are placed in a heat treatment furnace and held at a set temperature, such as 500°C, for 10-30 minutes, followed by quenching.
[0065] Fabrication of flexible filter 1: Select a suitable biocompatible film material and use femtosecond laser cutting technology to uniformly process micropores on its surface. The pore size must ensure smooth blood flow and effectively intercept thrombus fragments.
[0066] The skirt structure 101 and the flexible filter 1 need to be trained before weaving. The specific steps are as follows: solution treatment at 850℃ for 3 hours, tensile cycle at 125MPa for 5 times, constrained aging at 400℃ for 0.5 hours, and stress-free aging at 400℃ for 2 hours to obtain a two-way shape memory alloy wire with a phase transformation temperature of about 37℃.
[0067] It should be noted that the method provided in this embodiment can be used not only for the collection of thrombi in the mesenteric artery lumen, but also for the collection of thrombi in other arterial lumen cavities.
[0068] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.
Claims
1. A thrombus collection device for endovascular thrombectomy of the superior mesenteric artery, characterized in that, The system includes a support frame positioned outside a flexible filter to support it. The flexible filter is deformable, with one end open. When unfolded, the flexible filter forms an internal cavity to accommodate thrombi. The support frame is elastic and has shape memory capabilities. One end of the support frame is connected to a support catheter, while the other end extends beyond the flexible filter. Multiple leaf-shaped deformable components are located at the end of the support frame extending beyond the flexible filter. Each leaf-shaped deformable component is connected to a traction catheter via a traction wire. The traction catheter passes through the support catheter. By operating the traction catheter, the leaf-shaped deformable components bend towards the central axis of the flexible filter to close it. The thrombectomy catheter with the thrombus moves relative to the support frame to allow the thrombus to fall into the flexible filter.
2. The thrombus collection device for endovascular thrombectomy of the superior mesenteric artery according to claim 1, characterized in that, It also includes a delivery sheath and a recovery sheath, which can move along the axial direction of the support conduit. The support skeleton is a hollow structure made of nickel-titanium alloy. The delivery sheath and recovery sheath can wrap the deformed support skeleton. The inner diameter of the delivery sheath and recovery sheath is smaller than the diameter of the flexible filter when it is stretched open.
3. The thrombus collection device for endovascular thrombectomy of the superior mesenteric artery according to claim 1, characterized in that, The flexible filter is made of a biocompatible thin film material, and multiple micropores are arranged on the circumferential surface of the flexible filter, with a micropore diameter of 100~120 micrometers.
4. The thrombus collection device for endovascular thrombectomy of the superior mesenteric artery according to claim 1, characterized in that, The flexible filter screen includes a first filter screen and a second filter screen, which are connected together. When the flexible filter screen is unfolded, the first filter screen is a cylindrical filter screen and the second filter screen is a conical filter screen. The end of the first filter screen furthest from the second filter screen is designed with a wavy structure to avoid damaging the blood vessel wall. A skirt structure is provided at the wavy structure to support the flexible filter screen. The skirt structure is made of nickel-titanium shape memory alloy wire.
5. A thrombus collection device for endovascular thrombectomy of the superior mesenteric artery according to claim 4, characterized in that, The support frame includes a first section, a second section, and a third section connected in sequence. The first section is conical, the second section is cylindrical, and the third section is the blade deformation assembly. The first section is connected to the support guide tube via a connector. The skirt structure is located near the end of the second section away from the first section, and the skirt structure does not extend beyond the second section.
6. A thrombus collection device for endovascular thrombectomy of the superior mesenteric artery according to claim 5, characterized in that, The first segment includes multiple first connectors, and the second segment includes multiple second connectors. One end of the first connector is connected to the connector. The second connector includes multiple long sections with openwork. Adjacent long sections are connected by V-shaped sections. Both ends of the second connector are pointed. One pointed end of the second connector is connected to the first connector.
7. A thrombus collection device for endovascular thrombectomy of the superior mesenteric artery according to claim 5, characterized in that, The blade deformation assembly includes a central connector with an opening in the middle section. One end of the drawing wire is connected to the opening. Bending members are respectively provided on both sides of the central connector, with one end of the bending member connected to one end of the central connector. The width of the blade deformation assembly away from the second section is less than the width of the middle section of the blade deformation assembly to ensure the closing effect of the blade deformation assembly. The length of the bending member is less than the length of the central connector.
8. A thrombus collection device for endovascular thrombectomy of the superior mesenteric artery according to claim 1, characterized in that, The drawing wire is a drawing alloy wire, which is woven from nickel-titanium alloy wire, and all drawing wires are woven.
9. A method for manufacturing a thrombus collection device for endovascular thrombectomy of the superior mesenteric artery according to any one of claims 1-8, characterized in that, Includes the following: Fabrication of the support frame: The raw material of the support frame is cut to form a cylindrical structure. The support frame is then fitted onto the outside of the inner cylinder of the mold. An outer cylinder of the mold is set on the outside of the support frame. The shape of the inner cylinder of the mold is the same as that of the flexible filter screen. The assembled support frame and the mold are placed together in a heat treatment furnace and kept at the set temperature for 10-30 minutes, followed by quenching. Making flexible filter screens: The flexible filter is placed inside the support frame, and the blade deformation component in the support frame extends beyond the flexible filter.
10. A method for manufacturing a thrombus collection device for endovascular thrombectomy of the superior mesenteric artery according to claim 9, characterized in that, The fabrication of the flexible filter includes the following: A flexible filter screen is made by selecting a biocompatible thin film material and forming multiple micropores by circumferential perforation of the biocompatible thin film material. One end of the flexible filter screen is made into a wave structure. The trained nickel-titanium shape memory alloy wires are connected to the wave structure of the flexible filter to form a skirt structure.