Serial thrombectomy device

Abstract

This application provides a tandem thrombectomy device, relating to the technical field of cardiovascular medical devices, comprising a plurality of thrombectomy stents connected in series. Each thrombectomy stent includes a cutting segment and a braided segment. The cutting segment is used to cut the thrombus, and the braided segment is used to collect the cut thrombus. At least one cutting segment has a portion of its structure composed of several expansion units, and this portion of the cutting segment is configured to expand radially outward when under tension. By setting thrombectomy stents connected in series, the uneven deformation between each thrombectomy stent compensates for any missed points during thrombectomy, enabling multiple thrombectomies to be completed in a single placement, improving thrombectomy efficiency and reducing the risk of thrombus dislodgement and infection. The unique expansion structure design allows the cutting segment to expand outward under tension, resulting in a tighter fit between the cutting segment and the vessel wall, more thoroughly scraping the thrombus, reducing the number of stent placements, and further reducing the risk of thrombus dislodgement and infection.

Description

Technical Field

[0001] This application relates to the technical field of cardiovascular medical devices, specifically to a series thrombectomy device. Background Technology

[0002] Currently, the main treatments for deep vein thrombosis (DVT) include anticoagulation therapy, local thrombolysis, and mechanical thrombectomy. However, some patients have contraindications to anticoagulation or thrombolysis, making mechanical thrombectomy the primary option. Mechanical thrombectomy mainly includes aspiration thrombectomy and stent thrombectomy. Aspiration thrombectomy results in significant blood loss and is less effective for subacute and chronic thrombosis. Stent thrombectomy, on the other hand, involves less blood loss and complications, has a shorter procedure time, is less invasive, and is less expensive, making it an increasingly popular choice.

[0003] However, existing thrombectomy stents use an arc-shaped opening to facilitate thrombus cutting and stent insertion into the sheath. This causes uneven force on the stent during thrombectomy, leading to tilting and poor stent apposition to the vessel wall. Consequently, thrombectomy is incomplete and requires repeated insertions, increasing surgical time and bleeding. On the other hand, due to their structural design, existing thrombectomy stents are prone to contraction during thrombectomy, preventing the outer wall of the stent from adhering to the inner wall of the blood vessel. This results in poor thrombus removal and also requires repeated insertions, increasing the risk of thrombus dislodgement and infection. Summary of the Invention

[0004] In view of this, the embodiments of this specification provide a series thrombectomy device, which uses a series combination of stents to compensate for missed thrombectomy points by utilizing the uneven deformation characteristics between the stents, so as to complete multiple thrombectomies with a single insertion, thereby improving thrombectomy efficiency and reducing the risk of thrombus dislodgement and infection.

[0005] The embodiments in this specification provide the following technical solutions:

[0006] This specification provides a series-connected thrombectomy device, comprising a plurality of thrombectomy brackets connected in series.

[0007] Each of the aforementioned thrombectomy stents includes a cutting segment and a braided segment, wherein the cutting segment is used to cut the thrombus and the braided segment is used to collect the cut thrombus;

[0008] At least one of the cut segments has a partial structure consisting of several expansion units, and the cut segment with a partial structure consisting of several expansion units is configured to expand radially outward when under tension.

[0009] The above technical solution involves setting up thrombectomy stents in series. By utilizing the uneven deformation of each stent, they can compensate for any missed points during thrombectomy, enabling multiple thrombectomies to be completed in a single placement. This improves thrombectomy efficiency and reduces the risk of thrombus dislodgement and infection. Furthermore, the unique tensile structure design allows the cut segment to expand outward under tension during thrombectomy, resulting in a tighter fit between the cut segment and the vessel wall, more thoroughly scraping away the thrombus, reducing the number of stent placements, and further lowering the risk of thrombus dislodgement and infection.

[0010] Preferably, the plurality of thrombectomy stents connected in series are a first thrombectomy stent and a second thrombectomy stent;

[0011] The first thrombectomy stent includes a first cut section and a first braided section;

[0012] The first cutting segment is made by laser cutting. The first end of the first cutting segment is an arc-shaped opening structure. The arc-shaped opening structure and the middle section of the first cutting segment are connected by several evenly distributed connecting rods.

[0013] The first braided segment is connected to the tail end of the first cutting segment to collect the thrombus cut off by the first cutting segment;

[0014] The second thrombectomy bracket includes a second cut section and a second braided section;

[0015] The second segment is made by laser cutting;

[0016] The first end of the second cutting segment includes several cutting rods evenly arranged circumferentially;

[0017] Several of the cutting rods are connected to a series connection point located at the end of the first braided section, so that the tension transmitted at the end of the first braided section can be evenly applied to the middle and end of the second cutting section.

[0018] The tail end of the second cut segment is connected to the head end of the second braided segment;

[0019] The second braided section is used to collect the thrombus cut off by the second cutting section;

[0020] At least one of the first and second cut segments has a partial structure composed of several of the aforementioned expansion units.

[0021] Preferably, the end of the cutting rod away from the first braided section is connected to several peeling rods, and adjacent peeling rods are spaced apart from each other in a direction away from the cutting rod. The middle section of the second cutting section is connected to the cutting rod through peeling rods.

[0022] The above technical solution involves setting up cutting rods and stripping rods that are evenly distributed circumferentially. The cutting rods can, on the one hand, divide the thrombus remaining on the first thrombectomy stent into small pieces, and on the other hand, evenly transfer the tension during thrombectomy to the subsequent stripping rod, the middle and end of the second cutting segment, and the second braided segment. This ensures that the deformation caused by tension on the middle and end of the second cutting segment is more uniform, guaranteeing that the middle and end of the second cutting segment can make uniform contact with the vessel wall, reducing missed points in thrombectomy and improving thrombectomy efficiency. The function of the stripping rod is to peel off the small pieces of thrombus cut by the cutting rod, facilitating the collection of thrombus by the subsequent second braided segment.

[0023] Preferably, the tail end of the first cut segment is uniformly provided with several limiting rings along the circumference, and the first braided segment is composed of several braided filaments interwoven with each other.

[0024] Each pair of braided filaments forms a braiding unit, and several braided filaments are evenly divided into several braiding units, with each group of braiding units corresponding to a number of limiting rings.

[0025] Two braided wires in each braided unit are threaded through the corresponding limiting ring, and the middle section of the braided wire is located on the limiting ring. The two ends of the braided wire meet at the connection point at the end of the first braided segment.

[0026] The above technical solution sets a limiting ring to restrict the movement of the braided wire, thereby ensuring that the first filter segment will not easily rotate or deviate during the tensile movement, thus ensuring stable collection of the cut thrombus.

[0027] Preferably, each of the braided threads is interwoven with the corresponding limiting ring on both sides in a one-on-one manner.

[0028] The above technical solution further restricts the displacement of the braided yarn relative to the limiting ring, thereby reducing the overall displacement of the first braided section.

[0029] Preferably, the first woven section has a straight section structure and a tapered closing structure in sequence in the direction away from the first cutting section. The filter openings on the straight section structure are larger than those on the tapered closing structure, and the filter openings on the tapered closing structure gradually decrease in size in the direction away from the first cutting section.

[0030] Preferably, the middle section of the first cut segment is composed of several stretching units arranged in a circumferential array.

[0031] Preferably, the first end of the arc-shaped opening structure is provided with a fixing ring for fixing the conduit.

[0032] Preferably, the middle section of the second cut segment is composed of several expansion units arranged in a circumferential array.

[0033] Preferably, the first braiding segment, the connecting point, the second cutting segment, and the second braiding segment are all coaxially arranged.

[0034] Compared with the prior art, the beneficial effects that at least one technical solution adopted in the embodiments of this specification can achieve include at least:

[0035] 1. By setting up thrombectomy stents in series, the uneven deformation of each stent can be used to compensate for missed thrombectomy points, enabling multiple thrombectomies to be completed in one placement, thereby improving thrombectomy efficiency and reducing the risk of thrombus dislodgement and infection.

[0036] 2. By setting up a tensile unit, the unique tensile structure design allows the cutting segment to expand outward under tension during thrombectomy, thereby making the cutting segment fit more tightly with the blood vessel wall, scraping the thrombus more thoroughly, reducing the number of stent placements, and further reducing the risk of thrombus dislodgement and infection. Attached Figure Description

[0037] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0038] Figure 1 This is a schematic diagram of the overall structure of a series bolt removal device according to this application;

[0039] Figure 2 This is a schematic diagram of the structure of the first segment in this application;

[0040] Figure 3 This is a schematic diagram of the basic unit configuration in this application as a conventional structure;

[0041] Figure 4 This is a schematic diagram of the basic unit configuration in this application, which is a traditional structure with added expansion elements;

[0042] Figure 5 This is a schematic diagram of the structure at the connection between the first cut segment and the first braided segment in this application;

[0043] Figure 6 This is a schematic diagram of the structure at the connection between the first woven segment and the second cut segment in this application;

[0044] Figure 7 This is a structural schematic diagram of the connection between the second cut segment and the second braided segment in this application;

[0045] Figure 8This is a schematic diagram of a structure in other embodiments of this application where the maximum diameter of the second cutting segment is greater than the maximum diameter of the first cutting segment;

[0046] Figure 9 This is a schematic diagram of the overall structure of the series bolt removal device in other embodiments of this application.

[0047] Reference numerals: 1. First thrombus retrieval bracket; 11. First cutting segment; 111. Arc-shaped opening structure; 112. Fixing ring; 113. Connecting rod; 12. First braided segment; 121. Straight segment structure; 122. Conical closing structure; 2. Second thrombus retrieval bracket; 21. Second cutting segment; 211. Cutting rod; 212. Peeling rod; 22. Second braided segment; 3. Tension unit; 4. Traditional structure; 5. Limiting ring; 6. Braided wire; 7. Connecting point; 8. Tip head. Detailed Implementation

[0048] The embodiments of this application will now be described in detail with reference to the accompanying drawings.

[0049] The following specific examples illustrate the implementation of this application. Those skilled in the art can easily understand other advantages and effects of this application from the content disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. This application can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this application. It should be noted that, in the absence of conflict, the following embodiments and features in the embodiments can be combined with each other. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0050] It should be noted that various aspects of embodiments within the scope of the appended claims are described below. It will be apparent that the aspects described herein can be embodied in a wide variety of forms, and any particular structure and / or function described herein is merely illustrative. Based on this application, those skilled in the art will understand that one aspect described herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number and aspects set forth herein can be used to implement the device and / or practice the method. Additionally, this device and / or method can be implemented using structures and / or functionalities other than one or more of the aspects set forth herein.

[0051] It should also be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of this application. The drawings only show the components related to this application and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0052] Additionally, specific details are provided in the following description to facilitate a thorough understanding of the examples. However, those skilled in the art will understand that practice can be carried out without these specific details.

[0053] Through in-depth research and improvement of existing thrombectomy stents, the inventors discovered that: Existing thrombectomy stents employ an arc-shaped opening to facilitate thrombus cutting and stent placement. This irregular structure causes uneven stress on the stent during thrombectomy, leading to tilting and poor stent apposition to the vessel wall. This results in incomplete thrombectomy, requiring repeated placements and increasing surgical time and bleeding. Furthermore, due to their inherent structural design, existing thrombectomy stents are prone to contraction during thrombectomy, preventing the outer wall of the stent from adhering to the inner wall of the blood vessel. This results in poor thrombus removal and also necessitates repeated placements, increasing the risk of thrombus dislodgement and infection.

[0054] Based on this, the embodiments of this specification propose a processing scheme that uses a series combination of stents to compensate for missed thrombectomy points by utilizing the uneven deformation characteristics between the stents, thereby achieving multiple thrombectomies in a single placement, improving thrombectomy efficiency and reducing the risk of thrombus dislodgement and infection.

[0055] The technical solutions provided by the various embodiments of this application are described below with reference to the accompanying drawings.

[0056] like Figure 1 As shown in the figure, this specification provides a series thrombectomy device, which includes a plurality of thrombectomy brackets connected in series.

[0057] Each thrombectomy stent includes a cutting segment and a braided segment. The cutting segment is used to cut the thrombus, and the braided segment is used to collect the cut thrombus.

[0058] At least one of the cut segments is composed of several expansion units 3. The cut segment, which is composed of several expansion units 3, is configured to expand radially outward when under tension.

[0059] In this embodiment, the several thrombectomy brackets connected in series are a first thrombectomy bracket 1 and a second thrombectomy bracket 2.

[0060] The first thrombectomy stent 1 includes a first cutting section 11 and a first braided section 12.

[0061] like Figure 1and Figure 2 As shown, the first cutting segment 11 is manufactured by laser cutting. The first end of the first cutting segment 11 is an arc-shaped opening structure 111, and a fixing ring 112 for fixing the catheter is provided at the first end of the arc-shaped opening structure 111. The fixing ring 112 and the arc-shaped opening structure 111 are fixed together as a whole. Through the traditional arc-shaped opening structure 111 design, combined with the fixing ring 112 to fix the catheter, the advantages of arc-shaped opening in cutting thrombi and inserting stent sheaths are retained.

[0062] The middle section of the first cutting segment 11 is connected to the tail end of the arc-shaped opening structure 111 by several evenly distributed connecting rods 113. One end of the connecting rod 113 is fixed to the arc-shaped opening structure 111, and the other end of the connecting rod 113 is fixed to the middle section of the first cutting segment 11, so as to realize the force transmission from the arc-shaped opening structure 111 to the middle section of the cutting segment.

[0063] The middle section of the first segment 11 is composed of several basic unit configurations arranged in a circumferential array.

[0064] In this embodiment of the application, the basic unit configuration of the middle section of the first cutting segment 11 is a tensile unit 3. The middle section of the first cutting segment 11 is formed by a plurality of tensile units 3 arranged in a circumferential array, so that the middle section of the first cutting segment 11 expands radially outward under the action of tensile force, thereby achieving a better fit to the blood vessel wall.

[0065] In other embodiments, such as Figure 3 and Figure 4 As shown, the middle section of the first cutting segment 11 can also be composed of several traditional structures 4 or a mixture of several traditional structures 4 and several expansion units 3.

[0066] like Figure 5 As shown, the tail end of the first cut segment 11 is connected to the head end of the first braided segment 12. Six limiting rings 5 ​​are evenly fixed around the tail end of the first cut segment 11. The first braided segment 12 is composed of twelve braided wires 6 interwoven with each other. The braided wires 6 are NiTi wires.

[0067] Each pair of braided threads 6 forms a braiding unit, and the six braiding units correspond one-to-one with the six limiting rings 5.

[0068] like Figure 5 and Figure 6As shown, in each braided unit, two braided wires 6 are threaded onto the corresponding limiting rings 5. After the first end of the braided wire 6 passes through the limiting ring 5, the middle section of the braided wire 6 abuts against the limiting ring 5. The braided wires 6 are intertwined on both sides of the limiting ring 5 in a one-on-one manner, and the first and last ends of the braided wires 6 meet at the connection point 7 located at the end of the first braided segment 12. By restricting the movement of the braided wires 6 by limiting the limiting rings 5, the thrombus dislodgement caused by displacement and rotation of the first braided segment 12 can be effectively reduced.

[0069] In other embodiments, the number of braided filaments 6 and limiting rings 5 ​​can also be other, such as fourteen braided filaments 6 paired with seven limiting rings 5, which can be adjusted as needed, and no further limitations are made here.

[0070] The first braided section 12 is divided into a straight section structure 121 and a tapered constriction structure 122, which are coaxially distributed sequentially in a direction away from the first cutting section 11. The diameter of the tapered constriction structure 122 gradually decreases in the direction away from the first cutting section 11, and the connection point 7 is fixed at the tail end of the tapered constriction structure 122. The filter openings on the straight section structure 121 are larger than those on the tapered constriction structure 122, and several filter openings on the tapered constriction structure 122 gradually decrease in size in the direction away from the first cutting section 11. The gradually decreasing size of the filter openings can effectively prevent small thrombi from dislodging.

[0071] The straight section 121 can be adjusted by changing the length of the braided wire 6. The longer the thrombus blockage in the patient's body, the longer the corresponding braided section should be, so as to collect the thrombus more completely.

[0072] like Figure 1 , Figure 6 and Figure 7 As shown, the second thrombectomy bracket 2 includes a second cutting section 21 and a second braided section 22.

[0073] The second cutting segment 21 is manufactured by laser cutting. The first end of the second cutting segment 21 includes several cutting rods 211 evenly arranged in the circumferential direction and several peeling rods 212 evenly arranged in the circumferential direction. The number of peeling rods 212 is twice that of the cutting rods 211.

[0074] In this embodiment, there are three cutting rods 211, which are evenly distributed circumferentially, and the head end of each cutting rod 211 is fixed to the connection point 7 at the tail end of the first braided section 12. The head ends of every two stripping rods 212 are fixedly connected to the same cutting rod 211, and the tail ends of the two stripping rods 212 on the same cutting rod 211 are far apart from each other in a direction away from the first braided section 12. In actual use, the three evenly distributed cutting rods 211 can, on the one hand, divide the residual thrombus of the first thrombectomy stent 1 into small pieces, and on the other hand, evenly transmit the pulling force during thrombectomy to the six stripping rods 212. Then, the pulling force is evenly transmitted to the middle section of the second cutting section 21 through the six stripping rods 212, so that the middle section of the second cutting section 21 can deform evenly when subjected to pulling force, ensuring that the second cutting section 21 can make uniform contact with the blood vessel wall and reducing the number of missed thrombectomy points. The two stripping rods 212 at the end of each cutting rod 211 can peel the thrombus, which has been divided into small pieces, from the vessel wall so that the second braided section 22 can collect the peeled thrombus.

[0075] In other embodiments, the number of cutting rods 211 may be four, five or other numbers. Similarly, the number of peeling rods 212 connected to each cutting rod 211 may be three or other numbers, depending on the situation, and no further limitations are made here.

[0076] The overall configuration of the middle section of the second cutting segment 21 is similar to that of the middle section of the first cutting segment 11, consisting of several circumferentially arrayed expansion units 3. The middle section of the second cutting segment 21 is fixedly connected to the tail ends of six dissecting rods 212. The tension is evenly transmitted to the middle section of the second cutting rod 211 through the tail ends of the six dissecting rods 212. Under the action of tension, the middle section of the second cutting segment 21, composed of expansion units 3, will expand radially outward, thereby better conforming to the blood vessel wall and achieving a better removal effect on the thrombus.

[0077] In other embodiments, the middle section of the second cut segment 21 may also be composed of several conventional structures 4 or a mixture of several conventional structures 4 and several expansion units 3.

[0078] The overall configuration of the second braided section 22 is similar to that of the first braided section 12, both consisting of twelve braided filaments 6 interwoven on six limiting rings 5. The difference lies in that the overall shape of the second braided section 22 is conical, the overall diameter of the second braided section 22 gradually decreases in the direction away from the second cutting section 21, and several braided filaments 6 located at the tail end of the second braided section 22 are fixed together by a tip 8.

[0079] Furthermore, the first braided segment 12, the connecting point 7, the first cutting segment 11, and the second braided segment 22 are all coaxially arranged. The braiding length, braiding diameter, and braiding density of the first braided segment 12 and the second braided segment 22 can all be adjusted according to actual needs, and are not limited here.

[0080] In this embodiment of the application, the maximum diameter of the first cutting segment 11 is equal to the maximum diameter of the second cutting segment 21.

[0081] In other embodiments, such as Figure 8 As shown, the maximum diameter of the second cutting segment 21 can also be set to be greater than the maximum diameter of the first cutting segment 11, so that the larger diameter second cutting segment 21 can effectively ensure the removal of residual thrombi.

[0082] In other embodiments, such as Figure 9 As shown, the number of stents connected in series can also be three or other numbers, depending on clinical needs.

[0083] The various embodiments in this specification are described in a progressive manner. The same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on describing the differences from other embodiments.

[0084] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A series-connected bolt removal device, characterized in that, It includes several thrombectomy stents connected in series; Each of the aforementioned thrombectomy stents includes a cutting segment and a braided segment, wherein the cutting segment is used to cut the thrombus and the braided segment is used to collect the cut thrombus; At least one of the cut segments is partially composed of several expansion units (3), and the cut segment partially composed of several expansion units (3) is configured to expand radially outward when under tension; Several thrombectomy stents connected in series are designated as the first thrombectomy stent (1) and the second thrombectomy stent (2); The first thrombectomy bracket (1) includes a first cut section (11) and a first braided section (12); The first cutting segment (11) is made by laser cutting. The first end of the first cutting segment (11) is an arc-shaped opening structure (111). The arc-shaped opening structure (111) and the middle section of the first cutting segment (11) are connected by several evenly distributed connecting rods (113). The first braided segment (12) is connected to the tail end of the first cutting segment (11) to collect the thrombus cut off by the first cutting segment (11); The second thrombectomy bracket (2) includes a second cut section (21) and a second braided section (22); The second cut segment (21) is made by laser cutting; The first end of the second cutting segment (21) includes several cutting rods (211) evenly arranged in the circumferential direction; Several of the cutting rods (211) are connected to the connection point (7) at the end of the first braided section (12) so that the tension transmitted at the end of the first braided section (12) can be evenly applied to the middle and end of the second cutting section (21). The tail end of the second cut segment (21) is connected to the head end of the second braided segment (22); The second braided segment (22) is used to collect the thrombus cut off by the second cutting segment (21); At least one of the first cut segment (11) and the second cut segment (21) has a partial structure composed of several of the stretching units (3).

2. The series-connected bolt removal device according to claim 1, characterized in that, The end of the cutting rod (211) away from the first braided section (12) is connected to several peeling rods (212), and the adjacent peeling rods (212) are far away from each other in the direction away from the cutting rod (211). The middle section of the second cutting section (21) is connected to the cutting rod (211) through the peeling rods (212).

3. The series-connected bolt removal device according to claim 1, characterized in that, The tail end of the first cutting segment (11) is uniformly provided with several limiting rings (5) along the circumferential direction, and the first braided segment (12) is composed of several braided filaments (6) interwoven with each other; Each pair of braided filaments (6) forms a braided unit, and several braided filaments (6) are evenly divided into several braided units, with each group of braided units corresponding to several limiting rings (5). The two braided wires (6) in each braided unit are threaded through the corresponding limiting ring (5), and the middle section of the braided wire (6) is located on the limiting ring (5). The two ends of the braided wire (6) meet at the connection point (7) at the end of the first braided segment (12).

4. The series-connected bolt removal device according to claim 3, characterized in that, Each of the braided threads (6) is interwoven with each other in a one-on-one manner on both sides of the corresponding limiting ring (5).

5. The series-connected bolt removal device according to claim 1, characterized in that, The first woven section (12) consists of a straight section structure (121) and a tapered closing structure (122) in the direction away from the first cutting section (11). The filter openings on the straight section structure (121) are larger than those on the tapered closing structure (122), and the filter openings on the tapered closing structure (122) gradually decrease in size in the direction away from the first cutting section (11).

6. The series-connected bolt removal device according to claim 1, characterized in that, The middle section of the first cut segment (11) is composed of several stretching units (3) arranged in a circumferential array.

7. The series-connected bolt removal device according to claim 1, characterized in that, The first end of the arc-shaped opening structure (111) is provided with a fixing ring (112) for fixing the conduit.

8. The series-connected bolt removal device according to claim 1, characterized in that, The middle section of the second cut segment (21) is composed of several expansion units (3) arranged in a circumferential array.

9. The series-connected bolt removal device according to claim 1, characterized in that, The first braided segment (12), the connecting point (7), the second cutting segment (21) and the second braided segment (22) are all coaxially arranged.

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