Thrombectomy device and system

Abstract

The application provides a stent-retrieving device and a stent-retrieving system. The stent-retrieving device comprises an outer support and an inner support, and the outer support is rotatably sleeved outside the inner support. The outer support comprises a plurality of fixed rods which are uniformly distributed around the rotation axis of the inner support, and the fixed rods have first outer convex parts. The inner support comprises a plurality of movable rods which are uniformly distributed around the rotation axis, and the number of the movable rods is equal to that of the fixed rods. The movable rods have second outer convex parts, and the inner support has an unfolded position and a folded position. The second outer convex parts are provided with cutting parts, and the second outer convex parts and the corresponding first outer convex parts are provided with a film. When the inner support is in the unfolded position, the outer support, the inner support and the film enclose the circumference of the stent-retrieving device. The film also encloses a distal opening formed between the first outer convex parts and the second outer convex parts, and / or the stent-retrieving device further comprises a distal pocket which is arranged at the distal end of the stent-retrieving device and covers part of the first outer convex parts and part of the second outer convex parts. The stent-retrieving system is provided with the stent-retrieving device, and the stent-retrieving device has high stent-retrieving efficiency, good stent-leakage prevention effect and no damage to blood vessels.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of medical devices, in particular to a thrombectomy device and a thrombectomy system provided with the same. BACKGROUND

[0002] Thrombosis refers to the formation of abnormal blood clots in circulating blood or blood deposits on the inner wall of the heart or the wall of blood vessels due to certain inducements during the life of a human or an animal. Thrombosis occurs throughout the body, not only in myocardial infarction, deep vein thrombosis, or cerebral vascular thrombosis, but also in any blood vessels in the body. The incidence of venous thrombosis is higher than that of arterial thrombosis, and the ratio of the two can reach 4:1. Venous thrombosis accounts for 40% to 60% of thrombotic mechanisms. The incidence of occlusive coronary artery thrombosis is 15% to 95%, and 90% of thrombosis is associated with atherosclerotic plaques. Thrombosis causes blood vessel occlusion, blood flow obstruction, and related blood vessel-dependent tissue ischemia, hypoxia, and even necrosis, resulting in symptoms of dysfunction of the corresponding tissue and organ.

[0003] For the treatment of thrombosis, early treatment was mainly by using anticoagulant drugs, but the treatment effect was not obvious, the recanalization rate was low, the recanalization time was long, and some patients were not suitable for thrombolytic therapy. Subsequently, a thrombectomy device was developed, which provides a new and efficient recanalization treatment method for thrombosis patients, and the mechanical thrombectomy operation time is short and the related complications are few, which is the research hotspot in the field of thrombosis treatment. At present, the thrombectomy devices on the market have single-layer structure and double-layer structure. However, the existing thrombectomy devices have the following disadvantages: since the stents of the thrombectomy devices are mostly laser-cut tubes or wire materials that are woven into stents with large and small meshes, there is a problem of thrombus leakage during thrombectomy, which makes the thrombectomy not clean, and there is a risk of scratching the inner wall of the blood vessel. SUMMARY

[0004] In order to solve the above problems, the main purpose of the present application is to provide a thrombectomy device with high thrombectomy efficiency, good thrombus leakage prevention effect and the risk of damaging the inner wall of the blood vessel during thrombectomy.

[0005] Another purpose of the present application is to provide a thrombectomy system provided with the above-mentioned thrombectomy device.

[0006] In order to achieve the main purpose of the present application, the present application provides a device for removing thrombus, which comprises an outer support and an inner support, the outer support is rotatably sleeved outside the inner support; the outer support comprises a plurality of fixed rods which are uniformly distributed around the rotation axis of the inner support, the fixed rods have first outer convex portions between the first proximal ends and the first distal ends; the inner support comprises a plurality of moving rods which are uniformly distributed around the rotation axis, the number of the moving rods is equal to that of the fixed rods, the moving rods have second outer convex portions between the second proximal ends and the second distal ends, the inner support has an unfolded position and a folded position; along the unfolding direction of the inner support, the downstream end side of the second outer convex portion is provided with a cutting portion, the second outer convex portion is provided with a film between itself and the first outer convex portion located at the upstream end and adjacent to itself; when the inner support is in the unfolded position, the film is unfolded, along the unfolding direction, the moving rods are attached to the fixed rods located at the downstream end and adjacent to themselves, the film also closes the distal opening formed between the first outer convex portion and the second outer convex portion connected to itself, and / or the device for removing thrombus further comprises a distal pocket, the first distal end, the second distal end and the distal pocket are connected, and the distal pocket covers part of the first outer convex portion and part of the second outer convex portion.

[0007] As can be seen from the above, before the device for removing thrombus enters the blood vessel, the inner support of the device is in the folded position; after the device for removing thrombus enters the blood vessel and is placed at the thrombus, the device is self-expanded and unfolded, the first outer convex portions of the outer support are attached to the wall of the blood vessel, and then the outer support and the inner support of the device for removing thrombus are embedded in the thrombus; after the outer support and the inner support are embedded in the thrombus, the inner support is controlled to rotate to the unfolded position, during the movement of the inner support to the unfolded position, the cutting portion on the inner support cuts the thrombus, and the gradually unfolded film gathers the thrombus into the space surrounded by the outer support, the inner support and the film; when the inner support is in the unfolded position, the outer support, the inner support and the film or the outer support, the inner support, the film and the distal pocket form a space which is closed in the circumferential direction and the distal end of the device for removing thrombus, thereby the thrombus is collected in the space and the thrombus leakage during the withdrawal of the device for removing thrombus is avoided.

[0008] Further, when the inner support is in the unfolded position, the film also closes the proximal opening formed between the first outer convex portion and the second outer convex portion connected to itself; and / or the device for removing thrombus further comprises a proximal pocket, the first proximal end, the second proximal end and the proximal pocket are connected, and the proximal pocket covers part of the first outer convex portion and part of the second outer convex portion.

[0009] As can be seen from the above, the above design makes the thrombus in the device for removing thrombus not leak from the proximal side during the withdrawal of the device, especially during the withdrawal of the device into the delivery sheath, the thrombus is effectively prevented from being squeezed out from the proximal side due to the deformation of the device for removing thrombus caused by the squeezing.

[0010] Further, the distal pocket has a first dense mesh structure, or the distal pocket is made of a microporous film material; the proximal pocket has a second dense mesh structure, or the proximal pocket is made of a microporous film material.

[0011] From the above, the design makes the blood in the blood vessel flow during the thrombus extraction process, reduces the risk in the operation, filters and intercepts the thrombus fragments, avoids the thrombus fragments flowing back to the blood vessel with the blood, and guarantees the complete removal rate of the thrombus.

[0012] Further, the first outer convex part has a first arc segment, a second arc segment and a support segment, the first arc segment is connected between the first distal end and the support segment, the second arc segment is connected between the first proximal end and the support segment, the distal end pocket covers the first arc segment, and the proximal end pocket covers the second arc segment; the second outer convex part has a third arc segment, a fourth arc segment and a cutting segment, the third arc segment is connected between the second distal end and the cutting segment, the fourth arc segment is connected between the second proximal end and the cutting segment, the distal end pocket covers the third arc segment, the proximal end pocket covers the fourth arc segment, and the cutting part is arranged on the cutting segment.

[0013] From the above, the design is beneficial to the withdrawal of the thrombus extraction device into the delivery sheath, avoids the existence of sharp parts of the outer stent, and prevents the outer stent from scratching the blood vessel.

[0014] Further, the distal end pocket has a first sleeve part and a first cover part, the first distal end and the second distal end are inserted into the first sleeve part, and the first arc segment and the third arc segment are located in the first cover part; the proximal end pocket has a second sleeve part and a second cover part, the first proximal end and the second proximal end are inserted into the second sleeve part, and the second arc segment and the fourth arc segment are located in the second cover part.

[0015] From the above, the sleeve part of the pocket cooperates with the ends of the fixed rods and the movable rods, reliably fixes the pocket on the stent, limits the fixed rods and the movable rods, and ensures that the inner stent can reliably rotate relative to the outer stent; the cover part can shield and close the openings between the arc segments of the fixed rods and the arc segments of the movable rods when the inner stent is in the expanded position, and further cooperates with the outer stent, the inner stent and the membrane to block the thrombus in the thrombus extraction device, effectively preventing the thrombus from leaking.

[0016] Further, when the membrane does not close the distal end opening and the proximal end opening, the inner side of the support segment is provided with a first membrane connecting part, the first side of the membrane is connected with the first membrane connecting part, and the second side of the membrane is connected with the cutting segment; when the membrane closes the distal end opening and the proximal end opening, the inner side of the first outer convex part is provided with a second membrane connecting part, and the first side of the membrane is connected with the second membrane connecting part.

[0017] From the above, the membrane connecting part is convenient for the connection between the membrane and the fixed rods and limits the membrane in the axial direction of the thrombus extraction device; and the connection positions between the membrane and the fixed rods and the movable rods can be set according to whether the thrombus extraction device is provided with the distal end pocket and the proximal end pocket and the requirements for preventing the thrombus from leaking.

[0018] Further, the distal end pocket is provided with a first developing part, the proximal end pocket is provided with a second developing part, the fixed rods are provided with a third developing part, and / or the movable rods are provided with a fourth developing part.

[0019] From the above, the above design facilitates intraoperative determination of the exact position of the thrombectomy device, ensures that the thrombectomy device can cover the area where the thrombus is located, and guarantees the thrombectomy effect and thrombus removal rate.

[0020] Further, the thrombectomy device further comprises a fixing member mounted on the first proximal end.

[0021] From the above, the fixing member can further limit each fixed rod and each movable rod, guarantee the reliability of the rotation of the inner stent relative to the outer stent, and reliably fix the pocket body at the end of the fixed rod and the movable rod. In addition, the fixing member can be connected to the delivery device, thereby facilitating the control of the movement of the thrombectomy device and the rotation of the inner stent relative to the outer stent.

[0022] In order to achieve another object of the present application, the present application provides a thrombectomy system comprising a delivery device and a delivery sheath, the delivery device being movably arranged in the delivery sheath, wherein the thrombectomy system further comprises the above-mentioned thrombectomy device, the proximal side of the thrombectomy device being connected to the delivery device; the delivery device can drive the thrombectomy device to be taken out from the third distal end of the delivery sheath to the outside of the delivery sheath to make the thrombectomy device unfold, and control the inner stent to rotate from the folded position to the unfolded position; the delivery device can also drive the thrombectomy device to be compressed back into the delivery sheath from the third distal end.

[0023] From the above, the thrombectomy system uses the above-mentioned thrombectomy device, which can remove the thrombus without scratching the blood vessel, reduce the risk during the operation, and prevent the leakage of thrombus fragments during the thrombectomy process and the withdrawal of the thrombectomy device, thereby guaranteeing the complete removal rate of the thrombus.

[0024] Further, the delivery device comprises a first driving rod connected to the second proximal end, and the first driving rod can drive the inner stent to rotate relative to the outer stent; or the delivery device comprises a second driving rod and a third driving rod, the second driving rod is connected to the first proximal end, the third driving rod is arranged in the second driving rod, and the third driving rod is connected to the second proximal end, and the third driving rod can drive the inner stent to rotate relative to the outer stent.

[0025] From the above, the connection design of the delivery device and the thrombectomy device enables the delivery device to reliably drive the inner stent to rotate relative to the outer stent, grasp the thrombus, and prevent the leakage of the grasped thrombus. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 is a structure diagram of the inner stent of the thrombectomy device embodiment of the present application in the folded position.

[0027] Figure 2 is a structure diagram of the inner stent of the thrombectomy device embodiment of the present application in the unfolded position.

[0028] Figure 3 is a structural diagram of an outer support of the plug removal device embodiment of the present application.

[0029] Figure 4 is a structural diagram of a fixed rod of the plug removal device embodiment of the present application.

[0030] Figure 5 is a structural diagram of an inner support of the plug removal device embodiment of the present application from a first perspective.

[0031] Figure 6 is a structural diagram of the inner support of the plug removal device embodiment of the present application from a second perspective.

[0032] Figure 7 is a structural diagram of the inner support of the plug removal device embodiment of the present application from a first perspective when the inner support is in a retracted position.

[0033] Figure 8 is a structural diagram of the inner support of the plug removal device embodiment of the present application from a second perspective when the inner support is in an expanded position.

[0034] Figure 9 is a structural diagram of the inner support of the plug removal device embodiment of the present application from a second perspective when the inner support is in an expanded position.

[0035] Figure 10 is a structural diagram of a distal pocket of the plug removal device embodiment of the present application.

[0036] Figure 11 is a cross-sectional view of the plug removal device embodiment of the present application from a third perspective when the plug removal device is placed in a delivery sheath.

[0037] The present application is further described below in conjunction with the accompanying drawings and embodiments. DETAILED DESCRIPTION

[0038] Plug removal device embodiment

[0039] First, it is necessary to understand that the following terms "proximal end" refers to the end of the instrument or component away from the operator, and "distal end" refers to the end of the instrument or component away from the operator, the above orientation / position relationship is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0040] Reference Figure 1 and Figure 2The thrombus taking device 100 comprises an outer support 1, an inner support 2, a membrane 3, a distal pocket 4, a proximal pocket 5 and a fixing member 6. The outer support 1 is rotationally sleeved outside the inner support 2, that is, the overall outer contour formed by the outer support 1 covers outside the overall outer contour formed by the inner support 2, and the inner support 2 can rotate relative to the outer support 1 about a rotation axis, which is parallel to the axial direction of the thrombus taking device 100.

[0041] In combination Figure 3 and Figure 4 The outer support 1 comprises a plurality of fixed rods 11, which are uniformly distributed about the rotation axis of the inner support 2. The fixed rod 11 has a first proximal end 111, a first distal end 112 and a first outer convex portion 113, the first outer convex portion 113 being connected between the first proximal end 111 and the first distal end 112 and being arranged outward of the outer support 1, and the first outer convex portion 113 being used for contacting the blood vessel wall. The first proximal ends 111 of the plurality of fixed rods 11 surround a first limiting space, which functions like an axle hole; similarly, the first distal ends 112 of the plurality of fixed rods 11 surround a second limiting space, which functions like an axle hole.

[0042] In the embodiment, the first outer convex portion 113 has a first arc segment 1131, a second arc segment 1132 and a support segment 1133; the first arc segment 1131 is connected between the first distal end 112 and a first end of the support segment 1133, the second arc segment 1132 is connected between the first proximal end 111 and a second end of the support segment 1133, and the support segment 1133 extends substantially along the axial direction of the thrombus taking device 100. The support segment 1133 is used for contacting the blood vessel wall to ensure that the thrombus taking device 100 can be fixedly attached to the blood vessel wall; and the support segment 1133 is arc-shapedly connected between the first proximal end 111 and the first distal end 112 to prevent the fixed rod 11 from having a sharp portion, thereby avoiding that the outer support 1 scratches the blood vessel, reducing the risk during the operation, and facilitating the thrombus taking device 100 to be withdrawn from the distal end side of the delivery sheath tube 10 into the delivery sheath tube 10 and inserted from the proximal end side of the delivery sheath tube 10 into the delivery sheath tube 10.

[0043] In combination Figure 5 and Figure 6The inner support 2 comprises a plurality of movable rods 21 which are uniformly distributed around the rotation axis of the inner support 2. The movable rod 21 has a second proximal end 211, a second distal end 212, and a second outer convex portion 213 which is connected between the second proximal end 211 and the second distal end 212. The profile of the second outer convex portion 213 is similar to that of the first outer convex portion 113 of the fixed rod 11, so that the movable rod 21 can be accommodated inside the fixed rod 11 and can be more closely fitted to the fixed rod 11. The second proximal ends 211 of the plurality of movable rods 21 form a first rotation shaft portion which is inserted into the first limiting space, and the second distal ends 212 of the plurality of movable rods 21 form a second rotation shaft portion which is inserted into the second limiting space, so that the inner support 2 can rotate relative to the outer support 1 through the cooperation of the first rotation shaft portion with the first limiting space and the cooperation of the second rotation shaft portion with the second limiting space.

[0044] The inner support 2 has an unfolded position (as shown in Figure 2 , Figure 8 , Figure 9 ) and a folded position (as shown in Figure 1 , Figure 7 ). In this embodiment, the second outer convex portion 213 has a third arc segment 2131, a fourth arc segment 2132, and a cutting segment 2133. The third arc segment 2131 is connected between the second distal end 212 and a first end of the cutting segment 2133, the fourth arc segment 2132 is connected between the second proximal end 211 and a second end of the cutting segment 2133, and the cutting segment 2133 extends along the axial direction of the thrombus extraction device 100.

[0045] Along the unfolding direction R of the inner support 2, a cutting portion 21331 is arranged on the downstream end side of the second outer convex portion 213 and extends along the axial direction of the thrombus extraction device 100. In this embodiment, the cutting portion 21331 is arranged on the cutting segment 2133, and the length of the cutting portion 21331 is substantially equal to the length of the cutting segment 2133. Since the region of the movable rod 21 for cutting the thrombus is at the cutting segment 2133, only the cutting portion 21331 is arranged on the cutting segment 2133 without being arranged on the third arc segment 2131 and the fourth arc segment 2132, which can not only ensure effective cutting of the thrombus, but also simplify the structure of the movable rod 21 and reduce the processing difficulty of the movable rod 21.

[0046] In addition, since the outer stent 1 is sleeved outside the inner stent 2, the movable rod 21 almost adheres to the blood vessel wall without direct contact, thereby preventing the cutting part 21331 on the movable rod 21 from scratching the inside of the blood vessel and improving the thrombectomy safety; since the diameters of the fixed rod 11 and the movable rod 21 are small, the complete removal rate of the thrombus can still be ensured. Furthermore, the surface of the fixed rod 11 is smoothly transitioned, and the surface of the movable rod 21 is also smoothly transitioned except the cutting part 21331, thereby reducing the risk of the fixed rod 11 and the movable rod 21 scratching the blood vessel.

[0047] The fixed rod 11 and the movable rod 21 are made of shape memory materials, so that they have elastic deformation ability and can present a set expanded state when the thrombectomy device 100 is separated from the delivery sheath 10 and enters the blood vessel; in some embodiments, the fixed rod 11 and the movable rod 21 can be made of shape memory alloys such as nickel-titanium alloy.

[0048] In combination with Figure 7 and Figure 8 , along the expansion direction R of the inner stent 2, the second outer convex part 213 of the movable rod 21 is provided with a film 3 between the second outer convex part 213 of the fixed rod 11 located at the upstream end and adjacent to the movable rod 21. The connection mode between the film 3 and the fixed rod 11 and the movable rod 21 includes at least one of winding, bonding, welding and the like; the film 3 can be any elastic and biocompatible polymer material. Specifically, the film 3 can be a biocompatible polymer film with certain elasticity and not easy to tear, for example, the film 3 can be PET

the chemical name of PET film is polyethylene terephthalate, abbreviated as PET

the chemical name of PTFE film is polytetrafluoroethylene, abbreviated as PTFE

[0049] When the inner stent 2 is in the expanded position, the second side of the film 3 is driven by the movable rod 21, so that the film 3 is expanded, so that the film 3 seals the area formed between the cutting section 2133 of the second outer convex part 213 and the supporting section 1133 of the corresponding first outer convex part 113, and along the expansion direction R, the movable rod 21 is closely attached to the fixed rod 11 located at the downstream end and adjacent to the movable rod 21, thereby realizing the circumferential sealing of the thrombectomy device 100, preventing the thrombus from leaking out of the thrombectomy device 100 from the circumferential direction of the thrombectomy device 100 during the thrombectomy and the withdrawal to the delivery sheath 10, so as to ensure the complete removal rate of the thrombus.

[0050] In some embodiments, as Figure 8As shown, when the inner stent 2 is in the expanded position, the membrane 3 can not close the distal end opening 102 (which is the opening formed between the first arc segment 1131 and the third arc segment 2131) between the first outer protrusion 113 and the second outer protrusion 213 connected with itself, and the membrane 3 can not close the proximal end opening 101 (which is the opening formed between the second arc segment 1132 and the fourth arc segment 2132) between the first outer protrusion 113 and the second outer protrusion 213 connected with itself; at this time, a distal end pocket 4 needs to be arranged at the distal end of the thrombus removal device 100 (i.e. at the first distal end 112 and the second distal end 212), and in order to further reduce the risk of thrombus leakage during the thrombus removal and the retraction of the thrombus removal device 100 into the delivery sheath 10, a proximal end pocket 5 can also be arranged at the proximal end of the thrombus removal device 100 (i.e. at the first proximal end 111 and the second proximal end 211), and the specific arrangement manner is described below. In this embodiment, as an optional manner, the inner side of the support segment 1133 of the first outer protrusion 113 is provided with a first membrane connecting portion 11331, the first side of the membrane 3 is connected with the first membrane connecting portion 11331, and the first side of the membrane 3 is wrapped and fixed on the first membrane connecting portion 11331 when connected, and the membrane 3 can be further adhered and fixed on the first membrane connecting portion 11331 by an adhesive to ensure that the membrane 3 will not fall off from the first membrane connecting portion 11331, and at the same time, the first membrane connecting portion 11331 can also limit the membrane 3 in the axial direction of the thrombus removal device 100; the second side of the membrane 3 is connected with the cutting segment 2133 of the second outer protrusion 213, and the second side of the membrane 3 is preferably connected with the side of the cutting segment 2133 opposite to the cutting portion 21331 (i.e. the second side of the membrane 3 is substantially divided into two sides of the cutting segment 2133), and when connected, the membrane 3 can be adhered and fixed on the cutting segment 2133 by an adhesive, of course, the second side of the membrane 3 can be connected with other parts of the cutting segment 2133; in addition, the height of the membrane 3 in the circumferential direction of the thrombus removal device 100 is substantially consistent with the length of the support segment 1133 and the cutting segment 2133.

[0051] In some embodiments, as Figure 9As shown, when the inner stent 2 is in the expanded position, the membrane 3 also closes the distal opening 102 formed between the first outer protrusion 113 and the second outer protrusion 213 connected to itself; similarly, in order to further reduce the risk of thrombus leakage during thrombectomy and retraction of the thrombectomy device 100 into the delivery sheath 10, the membrane 3 also closes the proximal opening 101 formed between the first outer protrusion 113 and the second outer protrusion 213 connected to itself; at this time, the close fit between the membrane 3 and the fixed rod 11 and the movable rod 21 can also prevent thrombus leakage during thrombectomy and retraction of the thrombectomy device 100 into the delivery sheath 10. In order to further ensure that the thrombus does not leak, a distal pocket 4 can still be provided at the distal end of the thrombectomy device 100, and a proximal pocket 5 can be provided at the proximal end of the thrombectomy device 100. In this embodiment, as an optional way, the inner side of the first outer protrusion 113 is provided with a second membrane connecting portion, which includes the inner side of the first arc segment 1131, the second arc segment 1132 and the support segment 1133, the first side of the membrane 3 is connected to the second membrane connecting portion, and the first side of the membrane 3 is wrapped and fixed on the second membrane connecting portion when connected, and the membrane 3 can be further adhered and fixed on the second membrane connecting portion by an adhesive to ensure that the membrane 3 does not fall off the second membrane connecting portion, and at the same time, the second membrane connecting portion can also limit the membrane 3 in the axial direction of the thrombectomy device 100; the second side of the membrane 3 is connected to the second outer protrusion 213 (including the third arc segment 2131, the fourth arc segment 2132 and the cutting segment 2133), and the membrane 3 is adhered and fixed on the second outer protrusion 213 by an adhesive when connected. In addition, the length of the membrane 3 in the extension direction of the fixed rod 11 is substantially the same as the length of the first outer protrusion 113 and the second outer protrusion 213.

[0052] In combination Figure 10 , the distal pocket 4 is connected to the first distal end 112 of the fixed rod 11 and the second distal end 212 of the movable rod 21, and the distal pocket 4 covers part of the first outer protrusion 113 of the fixed rod 11 and part of the second outer protrusion 213 of the movable rod 21; the connection mode between the distal pocket 4 and the fixed rod 11 includes but is not limited to welding, bonding, etc.

[0053] As in the present embodiment, the distal pocket 4 has a first sleeve portion 41 and a first cover portion 42. When the distal pocket 4 is assembled with the outer support 1 and the inner support 2, the first distal end 112 of the fixed rod 11 and the second distal end 212 of the movable rod 21 are both inserted into the first sleeve portion 41, so that the distal pocket 4 is reliably fixed with the outer support 1, while assisting in limiting the fixed rod 11 and the movable rod 21, and ensuring that the inner support 2 can rotate relative to the outer support 1. The first cover portion 42 is generally trumpet-shaped, and the first arc segment 1131 of the fixed rod 11 and the third arc segment 2131 of the movable rod 21 are located in the first cover portion 42, so that the first cover portion 42 is latched on the first arc segment end of the outer support 1, and correspondingly latched on the third arc segment end of the inner support 2; preferably, the first cover portion 42 can also latch on a small part of the end of the support segment 1133 of the fixed rod 11 and a small part of the end of the cutting segment 2133 of the movable rod 21; it can be seen that the first cover portion 42 can achieve the purpose of shielding and latching the above-mentioned distal opening 102 when the inner support 2 is in the expanded position, preventing the thrombus from leaking from the distal opening 102 during the thrombus removal and the withdrawal of the thrombus removal device 100 to the delivery sheath 10, and at the same time cooperating with the outer support 1, the inner support 2 and the membrane 3 to block the thrombus in the thrombus removal device 100, effectively preventing the thrombus from leaking. In addition, through the structural design of the distal pocket 4, when the distal pocket 4 is used as the flow-approaching end, the flow resistance of the blood in the blood vessel can be appropriately reduced.

[0054] In some embodiments, the distal pocket 4 has a first dense mesh structure 421, which can be distributed throughout the distal pocket 4 (i.e. the entire distal pocket 4 is regarded as a dense mesh pocket); or the first dense mesh structure 421 is a local structure on the distal pocket 4. This design allows the blood in the blood vessel to flow normally during thrombus removal, thereby reducing the risk during the operation; at the same time, the distal pocket 4 also plays a role in filtering and intercepting thrombus fragments, preventing thrombus fragments from flowing back to the blood vessel with the blood, and ensuring the complete removal rate of the thrombus.

[0055] In some embodiments, the distal pocket 4 can be formed by a microporous membrane material, wherein the microporous membrane material can be an ePTFE membrane (expanded polytetrafluoroethylene film) or other microporous membrane materials with the same function and effect. The small mesh holes on the microporous membrane material can allow blood to pass through, while achieving the filtering and intercepting of thrombus fragments.

[0056] The proximal pocket 5 is connected with the first proximal end 111 of the fixed rod 11 and the second proximal end 211 of the movable rod 21, and the proximal pocket 5 is latched on part of the first outer convex portion 113 of the fixed rod 11 and part of the second outer convex portion 213 of the movable rod 21. The connection mode between the proximal pocket 5 and the fixed rod 11 includes but is not limited to welding, bonding and the like.

[0057] As in the present embodiment, the proximal pocket 5 has a second sleeve part 51 and a second cover part 52, when the proximal pocket 5 is assembled with the outer support 1 and the inner support 2, the first proximal end 111 of the fixed rod 11 and the second proximal end 211 of the movable rod 21 are both inserted into the second sleeve part 51, so that the proximal pocket 5 is reliably fixed with the outer support 1, while assisting in limiting the fixed rod 11 and the movable rod 21, and ensuring that the inner support 2 can reliably rotate relative to the outer support 1. The second cover part 52 is generally trumpet-shaped, the second arc segment 1132 of the fixed rod 11 and the fourth arc segment 2132 of the movable rod 21 are located in the second cover part 52, so that the second cover part 52 is covered on the second arc segment end of the outer support 1, and correspondingly, is also covered on the fourth arc segment end of the inner support 2. Preferably, the second cover part 52 can also cover a small part of the end of the support segment 1133 of the fixed rod 11 and a small part of the end of the cutting segment 2133 of the movable rod 21.

[0058] It can be seen that the proximal pocket 5 cooperates with the outer support 1, the inner support 2, the membrane 3, and the distal pocket 4 to form a closed space in the thrombus removal device 100 when the inner support 2 is in the expanded position, so as to confine the thrombus in the closed space, effectively preventing the thrombus from leaking; wherein the second cover part 52 can shield and cover the above-mentioned proximal opening 101 when the inner support 2 is in the expanded position, preventing the thrombus from leaking from the proximal opening 101 after the thrombus removal device 100 is removed, and in particular, effectively preventing the thrombus from being squeezed out from the proximal side due to the thrombus removal device 100 being squeezed and deformed during the process of being withdrawn into the delivery sheath 10, thereby improving the efficiency and success rate of the thrombus removal surgery. In addition, through the structural design of the proximal pocket 5, when the proximal pocket 5 serves as the flow-approaching end, the flow resistance of the blood in the blood vessel can be appropriately reduced.

[0059] In some embodiments, the proximal pocket 5 has a second dense mesh structure 521, which can be distributed throughout the proximal and distal pockets (i.e., the entire proximal pocket 5 is considered as a dense mesh pocket); or the second dense mesh structure 521 is a local structure on the proximal pocket 5. This design allows the blood in the blood vessel to flow normally during the thrombus removal process, thereby reducing the risk during the surgery; at the same time, the proximal pocket 5 also plays a role in filtering and intercepting thrombus fragments, preventing the thrombus fragments from flowing back to the blood vessel with the blood, and ensuring the complete removal rate of the thrombus.

[0060] In some embodiments, the proximal pocket 5 can be formed by a microporous membrane material, so that the small mesh holes on the microporous membrane material can allow the blood to pass through and achieve the filtering and intercepting of the thrombus fragments.

[0061] The fixing member 6 is arranged on the first proximal end 111 of the fixed rod 11, specifically, the fixing member 6 is arranged around the first proximal end 111 of each fixed rod 11; when the thrombectomy device 100 is provided with the proximal pocket 5, the fixing member 6 is arranged around the second sleeve part 51 of the proximal pocket 5, the fixing member 6 can further limit each fixed rod 11 and each movable rod 21, ensure the reliability of the rotation of the inner support 2 relative to the outer support 1, and reliably fix the proximal pocket 5 on the first proximal end 111 of the fixed rod 11 and the second proximal end 211 of the movable rod 21, and the fixing member 6 can be used for connecting the delivery device, thereby facilitating the control of the movement of the thrombectomy device 100 and the rotation of the inner support 2 relative to the outer support 1. Preferably, the fixing member 6 can also be arranged on the first distal end 112 of the fixed rod 11, i.e., the fixing member 6 is arranged around the first distal end 112 of each fixed rod 11; when the thrombectomy device 100 is provided with the distal pocket 4, the fixing member 6 is arranged around the first sleeve part 41 of the distal pocket 4, so that the distal pocket 4 is reliably fixed on the first proximal end 111 of the fixed rod 11 and the second proximal end 211 of the movable rod 21, to further limit each fixed rod 11 and each movable rod 21, and further ensure the reliability of the rotation of the inner support 2 relative to the outer support 1.

[0062] In some embodiments, the distal pocket 4 can be provided with a first developing part, and the proximal pocket 5 can be provided with a second developing part; and / or, the fixed rod 11 can be provided with a third developing part, and / or the movable rod 21 can be provided with a fourth developing part, wherein the third developing part can be the whole fixed rod 11, or the first proximal end 111 and the first distal end 112 of the fixed rod 11, and the fourth developing part can be the whole movable rod 21, or the second proximal end 211 and the second distal end 212 of the movable rod 21. The above design enables the doctor to clearly observe the relative position of the thrombectomy device 100 and the thrombus through the medical imaging equipment, ensures that the thrombectomy device 100 can cover the area where the thrombus is located, guarantees the thrombectomy effect and the thrombus removal rate, and improves the accuracy and safety of the operation.

[0063] In combination with Figure 11, the inner stent 2 of the thrombus extraction device 100 is in the collapsed position before the thrombus extraction device 100 enters the blood vessel, and the thrombus extraction device 100 is compressed and arranged in the delivery sheath tube 10. After the thrombus extraction device 100 is released from the distal end of the delivery sheath tube 10 into the blood vessel and placed at the thrombus, the thrombus extraction device 100 is self-expanded, the first outer protruding part 113 of the outer stent 1 is attached to the blood vessel wall, and then the outer stent 1 and the inner stent 2 of the thrombus extraction device 100 are embedded in the thrombus; and since the inner stent 2 is in the collapsed position, the movable rod 21 is basically folded in the inner side of the fixed rod 11, at this time, it is equivalent to only the outer stent 1, and a super large grid is formed between each fixed rod 11, which is more conducive to embedding the thrombus extraction device 100 in the thrombus, and when the subsequent movable rod 21 cuts the thrombus and cooperates with the film 3 to gather the thrombus into the thrombus extraction device 100, the integrity of the thrombus is better, thereby avoiding excessive fragmentation of the thrombus during the thrombus extraction process, effectively reducing or even eliminating the leakage of the thrombus, and improving the thrombus removal rate.

[0064] When the outer stent 1 and the inner stent 2 are embedded in the thrombus, the inner stent 2 is controlled to rotate to the expanded position; during the movement of the inner stent 2 to the expanded position, the cutting part 21331 on the inner stent 2 cuts the thrombus, and at the same time, the gradually expanded film 3 gathers the thrombus into the space surrounded by the outer stent 1, the inner stent 2 and the film 3; when the inner stent 2 is in the expanded position, the outer stent 1, the inner stent 2 and the film 3 or the outer stent 1, the inner stent 2, the film 3, the distal end pocket 4 and the proximal end pocket 5 form a space closed in the circumferential direction, the distal end and the proximal end of the thrombus extraction device 100, and then the thrombus is collected in the space and the thrombus leakage of the thrombus extraction device 100 during the withdrawal process is avoided.

[0065] As can be seen from the above, through the design of the thrombus extraction device 100, the thrombus extraction efficiency is high, the leakage prevention effect is good, and the blood vessel inner wall is not damaged during the thrombus extraction process.

[0066] Thrombus extraction system embodiment

[0067] The thrombus extraction system includes a delivery device, a delivery sheath tube 10 and a thrombus extraction device 100 as described in the above thrombus extraction device embodiments. The delivery device can be movably arranged in the delivery sheath tube 10, and the proximal end side of the thrombus extraction device 100 is connected with the delivery device; the delivery device can drive the thrombus extraction device 100 to be arranged outside the delivery sheath tube 10 from the third distal end of the delivery sheath tube 10 to make the thrombus extraction device 100 expand, and control the inner stent 2 to rotate from the collapsed position to the expanded position, and the delivery device can also drive the thrombus extraction device 100 to be compressed and collected into the delivery sheath tube 10 from the third distal end.

[0068] In some embodiments, the delivery device comprises a first driving rod 21 connected with the second proximal end 211 of the dynamic rod 21, and the first driving rod 21 can drive the inner stent 2 to rotate relative to the outer stent 1. The connection design of the delivery device and the thrombectomy device 100 enables the delivery device to reliably drive the inner stent 2 to rotate relative to the outer stent 1 to capture the thrombus and prevent the captured thrombus from leaking

[0069] In some embodiments, the delivery device comprises a second driving rod 21 and a third driving rod 21, wherein the second driving rod 21 is connected with the first proximal end 111 of the fixed rod 11, the third driving rod 21 is arranged in the second driving rod 21, and the third driving rod 21 is connected with the second proximal end 211 of the dynamic rod 21. Through the cooperation of the second driving rod 21 and the third driving rod 21, the outer stent 1 can be controlled to maintain different distances from the blood vessel through the second driving rod 21, so as to reduce the risk of damage to the blood vessel wall due to friction with the outer stent 1 and better protect the blood vessel; the third driving rod 21 controls the inner stent 2 to rotate relative to the outer stent 1, and can more reliably ensure that the dynamic rod 21 is closely attached to the fixed rod 11 located downstream of the deployment direction R and adjacent to itself (i.e., the aforementioned dynamic rod 21), so as to prevent the thrombus from leaking between the fixed rod 11 and the dynamic rod 21.

[0070] During the thrombectomy operation, the optimal puncture point position is determined according to the thrombus position of the lesion site, and then the puncture needle is used to perform puncture operation on the patient.

[0071] Then, the guide wire is placed along the puncture needle and passes through the thrombus, and then the puncture needle is withdrawn.

[0072] Then, the outer sheath is pushed to the appropriate position at the end of the thrombus with the help of the guide wire, and then the guide wire is withdrawn.

[0073] Then, the thrombectomy system is pushed into the outer sheath, so that the thrombectomy device 100 is located at the appropriate position, and then the outer sheath is withdrawn; subsequently, the thrombectomy device 100 is pushed out of the delivery sheath 10 by the delivery device, and the delivery sheath 10 is withdrawn.

[0074] Then, after the thrombectomy device 100 completes the embolization, the inner stent 2 is controlled by the delivery device to rotate to the deployed position to complete the thrombectomy.

[0075] Then, the delivery device withdraws the thrombectomy device 100 into the delivery sheath 10, and the delivery sheath 10 is withdrawn, and then the outer sheath is withdrawn; finally, the thrombectomy operation is completed.

[0076] As can be seen from the above, the thrombectomy system uses the above-mentioned thrombectomy device 100, so that when removing the thrombus, the blood vessel is not scratched, the intraoperative risk is reduced, and the problem of thrombus fragment leakage during the thrombectomy process and when the thrombectomy device 100 is withdrawn is prevented, thereby ensuring the complete removal rate of the thrombus.

[0077] Finally, it should be noted that the above description is only the preferred embodiment of the present application, and is not intended to limit the present application. For those skilled in the art, the present application can have various changes and modifications, and any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A device for removing a thrombus, characterized in that: it comprises an outer support and an inner support, the outer support being rotatably sleeved outside the inner support; the outer support comprises a plurality of fixed rods uniformly distributed around a rotation axis of the inner support, the fixed rods having a first outer convex portion between a first proximal end and a first distal end; the inner support comprises a plurality of moving rods uniformly distributed around the rotation axis, the number of moving rods being equal to that of the fixed rods, the moving rods having a second outer convex portion between a second proximal end and a second distal end, the inner support having an expanded position and a contracted position; a cutting portion is provided on a downstream end side of the second outer convex portion in an expansion direction of the inner support, a membrane is provided between the second outer convex portion and the first outer convex portion located on an upstream end side and adjacent to the second outer convex portion; when the inner support is in the expanded position, the membrane is expanded, the moving rods are attached to the fixed rods located on a downstream end side and adjacent to the moving rods in the expansion direction, the membrane also seals a distal opening formed between the first outer convex portion and the second outer convex portion connected to the membrane, and / or the device for removing a thrombus further comprises a distal pocket, the first distal end, the second distal end and the distal pocket are connected, and the distal pocket covers part of the first outer convex portion and part of the second outer convex portion.

2. The device for removing a thrombus according to claim 1, characterized in that: when the inner support is in the expanded position, the membrane also seals a proximal opening formed between the first outer convex portion and the second outer convex portion connected to the membrane; and / or the device for removing a thrombus further comprises a proximal pocket, the first proximal end, the second proximal end and the proximal pocket are connected, and the proximal pocket covers part of the first outer convex portion and part of the second outer convex portion.

3. The device for removing a thrombus according to claim 2, characterized in that: the distal pocket has a first dense mesh structure, or the distal pocket is made of a microporous membrane material; and / or the proximal pocket has a second dense mesh structure, or the proximal pocket is made of a microporous membrane material.

4. The device for removing a thrombus according to claim 2, characterized in that: the first outer convex portion has a first arc segment, a second arc segment and a support segment, the first arc segment is connected between the first distal end and the support segment, the second arc segment is connected between the first proximal end and the support segment, the distal pocket covers the first arc segment, and the proximal pocket covers the second arc segment; and / or the second outer convex portion has a third arc segment, a fourth arc segment and a cutting segment, the third arc segment is connected between the second distal end and the cutting segment, the fourth arc segment is connected between the second proximal end and the cutting segment, the distal pocket covers the third arc segment, the proximal pocket covers the fourth arc segment, and the cutting portion is provided on the cutting segment.

5. The device for removing a thrombus according to claim 4, characterized in that: the distal pocket has a first sleeve portion and a first cover portion, the first distal end and the second distal end are inserted into the first sleeve portion, and the first arc segment and the third arc segment are located in the first cover portion. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The proximal pocket has a second sleeve part and a second cover part, the first proximal end and the second proximal end are inserted into the second sleeve part, and the second arc segment and the fourth arc segment are located in the second cover part.

6. The thrombectomy device of claim 4, wherein: when the membrane does not seal the distal opening and the proximal opening, the inner side of the support segment is provided with a first membrane connecting part, the first side of the membrane is connected with the first membrane connecting part, and the second side of the membrane is connected with the cutting segment; when the membrane seals the distal opening and the proximal opening, the inner side of the first outer convex part is provided with a second membrane connecting part, and the first side of the membrane is connected with the second membrane connecting part.

7. The thrombectomy device of claim 2, wherein: the distal pocket is provided with a first developing part, and the proximal pocket is provided with a second developing part; and / or the fixed rod is provided with a third developing part, and / or the movable rod is provided with a fourth developing part.

8. The thrombectomy device of any one of claims 1 to 7, wherein: the thrombectomy device further comprises a fixing member, and the fixing member is mounted on the first proximal end.

9. A thrombectomy system, comprising: a delivery device; a delivery sheath, and the delivery device is movably arranged in the delivery sheath; characterized in that: the thrombectomy system further comprises the thrombectomy device of any one of claims 1 to 8, and the proximal side of the thrombectomy device is connected with the delivery device; the delivery device can drive the thrombectomy device to move out of the third distal end of the delivery sheath to the outside of the delivery sheath to make the thrombectomy device unfold, and control the inner support to rotate from the folded position to the unfolded position; the delivery device can also drive the thrombectomy device to be compressed back to the delivery sheath from the third distal end.

10. The thrombectomy system of claim 9, wherein: the delivery device comprises a first driving rod, the first driving rod is connected with the second proximal end, and the first driving rod can drive the inner support to rotate relative to the outer support; or the delivery device comprises a second driving rod and a third driving rod, the second driving rod is connected with the first proximal end, the third driving rod is arranged in the second driving rod, the third driving rod is connected with the second proximal end, and the third driving rod can drive the inner support to rotate relative to the outer support.

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