Medical device and medical system

Abstract

The application provides a medical device and a medical system. The medical system comprises a medical device, a delivery device and a suction device. The medical device comprises a support member and a mesh capture device. The mesh capture device is assembled on the outer periphery of the distal end of the support member. A plurality of capture units of the mesh capture device are arranged in sequence and at intervals along the axial direction of the support member. A first capture unit of the plurality of capture units is farther away from the proximal end of the support member than a second capture unit. The first capture unit has a first capture mesh surface which is entirely turned outward along the circumferential direction of the first capture unit and is bent towards the proximal end. The second capture unit has a second capture mesh surface which protrudes outward along the radial direction in part of the circumferential direction of the second capture unit. The second capture mesh surfaces of two adjacent second capture units can present circumferentially complete capture mesh surfaces along the circumferential direction of the support member. In this way, the flexibility and support performance are considered, and the blockage in the lumen with the characteristics of obsolescence and strong adhesion is effectively removed, and the blockage is prevented from escaping.

Description

TECHNICAL FIELD

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

[0002] Embolism refers to the phenomenon that abnormal substances that are not soluble in blood appear in circulating blood and flow with blood, and then block the lumen of blood vessels. Pulmonary embolism refers to the pulmonary circulation disorder caused by the blockage of pulmonary arteries or their branches by detached blood clots or other substances. It has the characteristics of high morbidity, high mortality, high recurrence and high misdiagnosis. When the pulmonary arteries or their branches are blocked, the mechanical blockage and neurohumoral factors will cause an increase in pulmonary circulation resistance, an increase in pulmonary artery pressure, a disorder in ventilation and blood flow ratio, and a series of changes such as right heart dysfunction, reduced systemic blood pressure, congestion and severe hypoxemia. In severe cases, pulmonary infarction, pulmonary atelectasis, damage to the functions of important organs such as heart, brain and kidney, and even sudden death can occur.

[0003] The conventional methods for treating thromboembolism and / or pulmonary embolism include reducing and / or removing abnormal substances, mainly including anticoagulant drug therapy, surgical treatment and minimally invasive interventional therapy. For patients with mild symptoms, conservative treatment with anticoagulant drugs can be used. However, for patients with severe symptoms and ineffective drug treatment, necessary surgery must be performed. Compared with traditional surgical treatment, minimally invasive interventional therapy has the characteristics of small trauma and fast recovery, and therefore becomes a promising technology for treating acute embolism or pulmonary embolism.

[0004] Minimally invasive intervention therapy often uses dissolution, rotational grinding, aspiration, basket or stent or balloon thrombectomy to remove abnormal substances such as thrombus, so as to restore blood flow in the lumen. Among them, the clinical effect of stent or basket thrombectomy device has been recognized by patients and doctors, and has become a research hotspot in recent years. By establishing a sheath channel, the thrombus component or the basket is sent into the thrombus position in the blood vessel, and the thrombus component or the basket is embedded in the thrombus and led out of the body through the sheath channel. However, the radial support force of the mesh capture device in the prior art is small, and it is easy to be deformed by the thrombus when encountering the thrombus, and in the process of withdrawing, the captured thrombus is easy to fall off from the surface of the mesh capture device or escape from the pores of the mesh capture device, the thrombus grabbing rate is low, which increases the risk of thrombus fragmentation and blockage of the distal end. In addition, for some thrombus with high hardness, the mesh capture device may not be able to take it away during the withdrawing process. There are also some medical devices with strong radial support force, but the rigidity of such devices also weakens the flexibility of the medical devices. Especially during the process of withdrawing into the catheter, the device may be stuck and accumulated due to the small space in the catheter lumen, which affects the smooth withdrawal of the device into the catheter, and may also cause the captured thrombus to fall off and escape to the distal branch. In the existing scheme, there are also some thrombus components with a closed distal end in the form of a cylindrical mesh, which have poor flexibility and may collapse when working in tortuous blood vessels, thereby increasing the probability of escape or rupture of the captured thrombus. At the same time, due to the large contact area with the blood vessel, the probability of damage to the blood vessel also increases, and for some thrombus closely attached to the blood vessel wall, it is difficult to scrape, capture and transfer the thrombus attached to the wall. In addition to removing thrombus, the existing technology also has the same problem when removing stones in the bile duct or ureter.

[0005] It should be noted that the information disclosed in the background section of the present application is only intended to deepen the understanding of the general background of the present application, and should not be regarded as acknowledging or implying in any form that the information constitutes prior art known to those skilled in the art. SUMMARY

[0006] The purpose of the present application is to provide a medical device and a medical system to solve the problems of low treatment efficiency and low treatment success rate in the prior art when treating thrombus, stones and other blockages.

[0007] To achieve the above-mentioned purpose, according to the first aspect of the present application, a medical device for removing blockages from a target lumen is provided, comprising: a support member; and a mesh capture device mounted on the outer periphery of the distal end of the support member;

[0008] The netted capturing device comprises a plurality of capturing units, the plurality of capturing units are arranged in sequence and spaced along the axial direction of the support member, the plurality of capturing units comprise first capturing units and a plurality of second capturing units, the first capturing units are farther away from the proximal end of the support member than the second capturing units, the first capturing units have first capturing net surfaces which are turned outward in the whole circumferential direction of the first capturing units and bent towards the proximal end, the second capturing units have second capturing net surfaces which are protruded radially outward in the partial circumferential direction of the second capturing units, and the second capturing net surfaces of two adjacent second capturing units can present circumferentially complete capturing net surfaces.

[0009] Optionally, the second capturing net surfaces are formed by the net tube being turned outward in the circumferential direction and bent towards the proximal end, or the second capturing net surfaces are formed by the net tube being protruded radially outward in the circumferential direction.

[0010] Optionally, the plurality of capturing units further comprise third capturing units, the first capturing units are farther away from the proximal end of the support member than the third capturing units, and the third capturing units have third capturing net surfaces which are protruded radially outward in the whole circumferential direction of the third capturing units.

[0011] Optionally, the third capturing net surfaces are formed by the net tube being protruded radially outward in the whole circumferential direction, and / or the third capturing net surfaces are deflected towards the proximal end or the distal end.

[0012] Optionally, the plurality of capturing units are connected as a whole, or the plurality of capturing units are not connected and form separate bodies.

[0013] Optionally, when the plurality of capturing units are connected as a whole, the netted capturing device is formed by one net tube, adjacent capturing units are connected through flat loading segments, the proximal end of the most distal capturing unit is connected with the support member and forms a distal connecting point, the proximal end of the most proximal capturing unit is connected with the support member and forms a proximal connecting point, and the flat loading segment between the proximal connecting point and the distal connecting point of the netted capturing device is not connected with the support member.

[0014] Optionally, when the plurality of capturing units form separate bodies, the netted capturing device is formed by a plurality of net tubes, the plurality of net tubes correspond to the plurality of capturing units one by one, and each capturing unit further has a flat loading segment which is fixedly sleeved on the outer circumferential surface of the distal end of the support member.

[0015] Optionally, the second capturing net surface is formed by locally turning the net tube circumferentially outward and bending towards the proximal end, the first capturing net surface and / or the second capturing net surface comprises a head end and a tail end arranged axially opposite to each other, the head end bends towards the proximal end, the tail end bends towards the head end, and the mesh density of the tail end is sparser than that of the head end.

[0016] Optionally, the second capturing net surface is formed by locally turning the net tube circumferentially outward and bending towards the proximal end, the tail end of the first capturing net surface and / or the second capturing net surface is curled outward to form an anti-injury end portion, and the anti-injury end portion is wrapped by a soft material.

[0017] Optionally, the second capturing net surface is formed by locally turning the net tube circumferentially outward and bending towards the proximal end, the tail end of the first capturing net surface and / or the second capturing net surface is curled outward to form an anti-injury end portion, and the anti-injury end portion is wrapped by a soft material.

[0018] Optionally, the third capturing net surface is formed by at least one of a spherical shape, a disc shape, a cylindrical shape, a mesh bag shape, and a mesh basket shape.

[0019] Optionally, the medical device further satisfies at least one of the following conditions:

[0020] The radial dimension of the at least one capturing unit after being fully deployed is greater than or equal to the diameter of the target lumen;

[0021] The mesh density of the capturing net surface on at least part of the capturing unit gradually becomes sparser from the center to the edge;

[0022] The mesh density of the mesh capturing device gradually becomes sparser from the distal end to the proximal end;

[0023] The radial dimension of the mesh capturing device gradually increases or decreases from the proximal end to the distal end;

[0024] The first capturing net surface is provided with a coating film, and the coating film covers part of the mesh holes of the first capturing net surface.

[0025] Optionally, the support member comprises a hollow inner core and a distal guide head, the distal guide head is arranged at the distal end of the hollow inner core, the hollow inner core has a rigid region and an elastic region arranged axially from the proximal end to the distal end, and the mesh capturing device is arranged on the elastic region.

[0026] To achieve the above-mentioned purposes, according to the second aspect of the present application, a medical system is provided, which comprises: any one of the medical devices; a delivery device for loading the medical device to deliver the medical device into a target lumen; and a suction device connected with the delivery device and applying suction force through the delivery device to suction the blockage in the target lumen.

[0027] In summary, the medical device for removing the obstruction from the target lumen provided by the present application comprises a support member and a mesh capture device assembled on the outer periphery of the distal end of the support member. The mesh capture device comprises a plurality of capture units arranged in sequence and spaced apart along the axial direction of the support member. The plurality of capture units comprises a first capture unit and a plurality of second capture units. The first capture unit is farther away from the proximal end of the support member than the second capture unit. The first capture unit has a first capture mesh surface that is flipped outwardly in its entirety in the circumferential direction and curved towards the proximal end. The second capture unit has a second capture mesh surface that protrudes radially outwardly in part of its circumferential direction. The second capture mesh surfaces of two adjacent second capture units can present a circumferentially complete arrangement of capture mesh surfaces in the circumferential direction of the support member. Taking the example of removing thrombus in an intervention blood vessel:

[0028] Firstly, the sequential arrangement of the plurality of capture units can segmentally remove the thrombus out of the body, with high thrombectomy efficiency and good thrombectomy effect. In particular, the capture units have a mesh structure and sufficient radial support force, and are not easily deformed when encountering thrombus, thus better scraping, capturing and transferring thrombus with obsolete and strong adhesion characteristics. Therefore, the thrombectomy effect is good, and the mesh structure can provide sufficient density of mesh holes to capture and intercept thrombus. The captured thrombus is not easily detached from the capture mesh surface or escape from the mesh holes, and the success rate of capturing thrombus is high.

[0029] Secondly, the second capturing unit of the plurality of capturing units adopts a second capturing mesh surface which locally protrudes outward in the circumferential direction, which increases the flexibility and adaptability of the entire device in tortuous blood vessels and blood vessels with variable diameters, reduces the possibility of excessive deformation and inward collapse of the mesh structure in tortuous blood vessels and blood vessels with variable diameters, so that the medical device can be applicable to various lumens, while also reducing the resistance of the device to retract and be accommodated into the delivery device. At the same time, the second capturing mesh surfaces of the two adjacent second capturing units can also form a circumferentially complete capturing mesh surface to facilitate the capture and transfer of thrombus. Considering the risk of thrombus falling off and escaping from the second capturing mesh surface, the first capturing unit is arranged at the distal end of the medical device, so that the first capturing unit itself can capture thrombus and further intercept thrombus escaping from the proximal end, thereby improving the success rate of thrombus capture. In addition, the first capturing unit adopts an outwardly turned and curved structure design, so that the contact area of the first capturing mesh surface with the blood vessel is small, thereby reducing the damage to the blood vessel wall when scraping the thrombus, and facilitating smooth guidance and accommodation into the delivery device during the retraction process without causing the captured thrombus to fall off and escape. In summary, the combination design of the first capturing unit and the plurality of second capturing units can not only segmentally bring the thrombus out of the body to improve the thrombectomy efficiency, but also take into account the flexibility, support, damage to the blood vessel and retraction resistance of the entire device. In particular, it can effectively remove thrombus with old and strong adhesion characteristics in the blood vessel and effectively prevent thrombus from escaping, thereby improving the success rate of thrombus capture.

[0030] Since the medical system provided by the present application belongs to the same inventive concept as the medical device provided by the present application, the medical system provided by the present application has all the advantages of the medical device provided by the present application, so the beneficial effects of the medical system provided by the present application will not be described one by one here. BRIEF DESCRIPTION OF DRAWINGS

[0031] Those skilled in the art will understand that the provided drawings are used to better understand the present application, and do not constitute any limitation on the scope of the present application. Among them:

[0032] Figure 1 is the front view of the medical system in embodiment one of the present application;

[0033] Figure 2 is the perspective view of the medical device when fully deployed in embodiment one of the present application;

[0034] Figure 3 is the front view of the medical device when fully deployed in embodiment one of the present application;

[0035] Figure 4a is the partial view of the adjacent second capturing unit of the medical device when fully deployed in embodiment one of the present application;

[0036] Figure 4b is a side view of the medical device in embodiment one when it is fully deployed, the side view is from the right side to the left side of the front view of Figure 4a ;

[0037] Figure 5 is a perspective view of the first capture unit at the distal end in embodiment one when it is fully deployed;

[0038] Figure 6a is a perspective view of the second capture unit in embodiment one when it is fully deployed;

[0039] Figure 6b is a perspective view of the second capture unit in Figure 6a ;

[0040] Figure 7a is a schematic view of the medical device in embodiment one when the guide wire is sent to the target lesion during surgery;

[0041] Figure 7b is a schematic view of the medical device in embodiment one when the sheath and the delivery catheter are sent to the thrombus along the guide wire during surgery;

[0042] Figures 7c to 7d are schematic views of the medical device in embodiment one when the delivery catheter is retracted to release the multiple capture units;

[0043] Figure 7e is a schematic view of the medical device in embodiment one when all the capture units are fully deployed and embedded in the thrombus during surgery;

[0044] Figure 7f is a schematic view of the medical device in embodiment one when the sheath and the delivery catheter are sent to the thrombus along the guide wire during surgery;

[0045] Figure 8 is a front view of the first capture unit with a covering in embodiment two;

[0046] Figure 9a is a front view of the first capture unit with a developing element in embodiment three;

[0047] Figure 9b is a partial view of the first capture unit in Figure 9a ;

[0048] Figure 10a is a schematic view of the first capture unit with a larger curling angle in embodiment four;

[0049] Figure 10b is a schematic view of the second capture unit with a larger curling angle in embodiment four;

[0050] Figure 11a is another exemplary structure of the first capturing unit in the fourth embodiment of the present application, wherein the tail end of the first capturing net surface adopts a folded line-shaped net surface, and the head end adopts an arc-shaped net surface;

[0051] Figure 11b is another exemplary structure of the second capturing unit in the fourth embodiment of the present application, wherein the tail end of the second capturing net surface adopts a folded line-shaped net surface, and the head end adopts an arc-shaped net surface;

[0052] Figure 12a is another exemplary structure of the first capturing unit in the fourth embodiment of the present application, wherein the tail end of the first capturing net surface is curled;

[0053] Figure 12b is Figure 12a is a partial schematic view of the first capturing unit in the fourth embodiment of the present application;

[0054] Figure 12c is another exemplary structure of the second capturing unit in the fourth embodiment of the present application, wherein the tail end of the second capturing net surface is curled;

[0055] Figure 13a is another exemplary structure of the first capturing unit in the fourth embodiment of the present application, wherein the head end and the tail end of the first capturing net surface both adopt folded line-shaped net surfaces, and are connected by an arc-shaped transition net surface;

[0056] Figure 13b is another exemplary structure of the second capturing unit in the fourth embodiment of the present application, wherein the head end and the tail end of the second capturing net surface both adopt folded line-shaped net surfaces, and are connected by an arc-shaped transition net surface;

[0057] Figure 14 is a front view of the medical device in the fifth embodiment of the present application, wherein the radial dimension of the net-shaped capturing device gradually decreases from the distal end to the proximal end when the net-shaped capturing device is fully unfolded;

[0058] Figure 15a is an exemplary structure of the medical device in the sixth embodiment of the present application, wherein each capturing unit is connected as a whole;

[0059] Figure 15b is another exemplary structure of the medical device in the sixth embodiment of the present application, wherein the mesh density of each capturing unit gradually decreases from the distal end to the proximal end;

[0060] Figure 15c is another exemplary structure of the medical device in the sixth embodiment of the present application, wherein a third capturing unit in the shape of a mesh basket is added.

[0061] In the drawings, the reference signs are explained as follows:

[0062] 100 - medical device; 110 - support member; 111 - distal guide head; 130 - mesh capture device; 131 - capture unit; 131a - flat loading section; 131b - tail end; 131c - head end; 131d - proximal end; 131e - mesh hole; 131f - mesh hole support rod; 131g - damage prevention end; 131h - soft material; 1311 - first capture unit; 1311a - first capture mesh surface; 1312 - second capture unit; 1312a - second capture mesh surface; 1313 - third capture unit; 1313a - third capture mesh surface; 1313b - protruding rod; 1314 - film; 1315 - developing element; 13151 - mounting rod; 13152 - developable body; 120 - developing ring; A1 - first mesh surface; A2 - second mesh surface; A3 - transition mesh surface; 300 - delivery device; 301 - sheath; 302 - delivery catheter; 500 - suction device; 501 - suction tube; 502 - connecting seat; 503 - hemostatic sealing valve; 504 - one-way valve; 10 - guidewire; 20 - blood vessel; 30 - thrombus. DETAILED DESCRIPTION

[0063] To make the objectives, advantages and features of the present application clearer, the following further describes the present application in detail with reference to the accompanying drawings and specific embodiments. It should be noted that the drawings are very simplified and not drawn to scale, and are only used to facilitate and clarify the purpose of assisting the description of the embodiments of the present application. In addition, the structures shown in the drawings are often part of the actual structures. In particular, the emphasis shown in each drawing is different, and sometimes different scales are used. It should also be understood that, unless specifically described or indicated, the terms "first", "second", "third" and the like in the description are only used to distinguish the components, elements, steps and the like in the description, and are not used to represent the logical relationship or sequential relationship between the components, elements, steps and the like.

[0064] In the present application, "proximal" and "distal" are the relative positions, directions of elements or actions relative to each other from the perspective of a doctor using the medical device, although "proximal" and "distal" are not restrictive, "distal" generally refers to the end of the medical device that first enters the patient's body during normal operation, and "proximal" generally refers to the end of the medical device that is close to the doctor during normal operation. The "distal" and "proximal" in the present application do not refer to the end of the structure, but to the relative position, for example, the distal end of the capture unit is not the end of the capture unit, but a position relatively close to the end of the capture unit. In this paper, "axial" generally refers to the direction along the central axis, such as the direction along the central axis of the capture unit or the support member, "radial" generally refers to the direction perpendicular to the axial direction, and "circumferential" refers to the direction around the central axis; "inner" refers to a position close to the central axis of the capture unit; "outer" refers to a position away from the central axis of the capture unit; "head end" is a position close to the inversion bend, and the head end of the capture unit corresponds to the distal end; "tail end" is a position further away from the inversion bend than the "head end". In this paper, the target lumen can be a blood vessel, or a non-blood vessel lumen such as a bile duct or a ureter.

[0065] The core idea of the present application is to provide a medical device and a medical system to solve the problem of low efficiency and poor effect in cleaning thrombus, stones and other blockages in the prior art. Taking thrombus as an example, the present application can improve the ability of the device to embed and capture thrombus, reduce the risk of fragmented thrombus escaping during withdrawal, and also effectively scrape and collect thrombus attached to the wall during transfer, and can reduce the difficulty of withdrawing into the catheter.

[0066] The following description is made with reference to the accompanying drawings. In the following description, the embodiments and features in the embodiments described below can be supplemented or combined with each other without conflict.

[0067] <Embodiment I>

[0068] First, take the example of cleaning thrombus in a blood vessel, but those skilled in the art can modify the following description to clean stones or other blockages after making appropriate modifications in details.

[0069] As shown in Figures 1 to 3 The present embodiment provides a medical system, which includes a medical device 100, a delivery device 300 and a suction device 500. The medical device 100 includes a support member 110 and a mesh capture device 130. The mesh capture device 130 is assembled on the outer periphery of the distal end of the support member 110 and is used to capture, transfer and export thrombus. The support member 110 is usually an elongated tubular structure, and a guide wire 10 (see Figures 7a to 7f). The main role of the support member 110 is to support the installation of the mesh capture device 130, and also to release and recover the mesh capture device 130 by manipulating the support member 110.

[0070] The mesh capture device 130 includes a plurality of capture units 131, which are arranged in sequence along the axial direction of the support member 110, and can be arranged at equal distances or non-equal distances. In this regard, those skilled in the art can set the distance between the capture units 131 according to the specific factors of the target lumen and the obstruction. Generally, the greater the distance between adjacent capture units 131, the better the flexibility of the medical device 100.

[0071] In the illustrated embodiment, the plurality of capture units 131 are provided in a split manner, that is, all the capture units 131 are independently connected to the support member 110 on the support member 110, rather than being connected to each other as a whole, so as to form a split mesh capture device 130. When the mesh capture device 130 is split, each capture unit 131 can be formed by a separate mesh tube, and all the capture units 131 are independently assembled on the support member 110. The mesh tube used in the present application can be a cut mesh tube or a braided mesh tube, and is preferably a cut mesh tube to further improve the radial support of the capture unit.

[0072] In other embodiments, the plurality of capture units 131 are connected to each other as a whole, thereby forming an integral or unitary mesh capture device 130. When the mesh capture device 130 is integral or unitary, only one mesh tube is needed to form the plurality of capture units 131.

[0073] Regardless of being split or integral or unitary, the number of capture units 131 is not less than three. The plurality of capture units 131 should include a first capture unit 1311 and a plurality of second capture units 1312, and the first capture unit 1311 is farther away from the proximal end of the support member 110 than all the second capture units 1312. The number of first capture units 1311 is usually only one, so that one first capture unit 1311 breaks, captures, intercepts and transfers the thrombus at the farthest end. The number of second capture units 1312 can be two or more. At least two second capture units 1312 break, capture, intercept and transfer the thrombus at the proximal end.

[0074] Further, the plurality of capture units 131 can also include a third capture unit 1313 (see Figures 15a to 15c), the first capturing unit 1311 is farther away from the proximal end of the support member 110 than all the third capturing units 1313. The relative positions of the third capturing units 1313 and the second capturing units 1312 have no special requirements. The number of the third capturing units 1313 can be one or more. The structure of the first capturing unit 1311 is different from that of the second capturing unit 1312 and the third capturing unit 1313, and the structure of the third capturing unit 1313 is different from that of the second capturing unit 1312. The structures of all the second capturing units 1312 are the same or different. Further, when the number of the third capturing units 1313 is more than one, the structures of the plurality of third capturing units 1313 are the same or different. The structure referred to herein includes shape and size, such as different shape, different size, or both different shape and size.

[0075] With reference to Figure 5 , Figures 6a to 6b Regardless of the first capturing unit 1311 or the second capturing unit 1312, these capturing units 131 have an axially integrally connected flat loading section 131a and a capturing net surface (corresponding to the first capturing net surface 1311a and the second capturing net surface 1312a) after being fully deployed. The flat loading section 131a can be sleeved on the outer peripheral surface of the support member 110, and the capturing net surface is arranged outwardly on the periphery of the flat loading section 131a and curved towards the proximal end direction of the capturing unit 131. As shown in Figure 5 After being fully deployed, the first capturing unit 1311 has the first capturing net surface 1311a which is entirely outwardly turned along the circumferential direction of itself and curved towards the proximal end direction of the first capturing unit 1311. The first capturing net surface 1311a is a complete umbrella surface. Figure 6a and Figure 6b After being fully deployed, the second capturing unit 1312 has the second capturing net surface 1312a which is partially outwardly turned along the circumferential direction of itself and curved towards the proximal end direction of the second capturing unit 1312. The second capturing net surface 1312a is an incomplete umbrella surface.

[0076] The first capturing unit 1311 and the second capturing unit 1312 can be prepared by different netting. When preparing the first capturing unit 1311, a part of the structure of the netting is turned over to form the first capturing net surface 1311a, and the other part of the structure of the netting is used as the flat loading segment 131a. When preparing the second capturing unit 1312, a part of the structure of the other netting is turned over to form the second capturing net surface 1312a, and the other part of the structure of the netting is used as the flat loading segment 131a. The transition zone between the capturing net surface and the flat loading segment 131a of each capturing unit is as smooth as possible to prevent stress concentration. For example, the first capturing net surface 1311a of the first capturing unit 1311 and the flat loading segment 131a are connected in an arc-shaped or linear transition, and the second capturing net surface 1312a of the second capturing unit 1312 and the flat loading segment 131a are also connected in an arc-shaped or linear transition.

[0077] In this embodiment, the first capturing unit 1311 and the plurality of second capturing units 1312 are combined to improve the treatment efficiency and effect, and increase the flexibility and adaptability of the medical device 100 in tortuous blood vessels and variable-diameter blood vessels. In particular, the partial curling design of the second capturing unit 1312 can further enhance the flexibility and adaptability of the device, thereby reducing the possibility of excessive deformation and inward collapse of the device in tortuous blood vessels and variable-diameter blood vessels. In addition, the device is easy to guide and store into the delivery device 300, and the resistance during withdrawal into the catheter is reduced, thereby facilitating delivery and recovery. It can be understood that the outward curling design not only reduces the contact area between the capturing unit 131 and the blood vessel wall, but also reduces the damage to the blood vessel wall during thrombectomy, thereby reducing the harm to the patient during treatment.

[0078] In more detail, when the capturing unit 131 is self-inflated and expanded, the thrombus can be collected in the curved capturing net surface, and then sucked out by the suction device 500. In particular, when the capturing net surface is in close contact with the inner wall of the blood vessel, the capturing unit 131 can effectively scrape the thrombus attached to the blood vessel during the withdrawal process. Therefore, for some thrombi closely attached to the blood vessel, the thrombi can be easily scraped, captured and transferred during the withdrawal process, thereby further increasing the probability of removing the thrombus. The capturing unit 131 has other functions. When the capturing unit 131 is self-inflated and expanded, the capturing net surface can cut and break large thrombi during the outward curling process, so that the suction device 500 can suck the broken thrombi, thereby improving the efficiency of removing the thrombi.

[0079] It should also be recognized that the capture unit 131 forms a three-dimensional mesh structure after being fully deployed, and this structure has relatively dense mesh holes and good radial support. In the process of taking out the thrombus, not only is it not easy to be deformed by the thrombus, but it can also effectively cut and break the thrombus and capture the thrombus. Moreover, during the withdrawal process, the captured thrombus is not easy to fall off the surface of the capture unit 131 or escape from the mesh holes of the capture unit 131, thereby improving the thrombus capture efficiency and reducing the risk of thrombus occluding the distal end of the blood vessel. Especially for some thrombus with relatively high hardness, the capture unit 131 is not easy to deform and can easily take the thrombus out of the body during the withdrawal process, thereby increasing the success rate of capturing the thrombus.

[0080] In addition, the tail end 131b of the first capture unit 1311 and the second capture unit 1312 is not closed, so it has good flexibility and is not easy to collapse when working in tortuous blood vessels and variable diameter blood vessels, thereby reducing the probability of thrombus escape or rupture. In addition, the structure design of the plurality of capture units 131 arranged in sequence can also accommodate the thrombus between the capture mesh surfaces of adjacent capture units 131, which is less likely to escape distally, and can also break the thrombus multiple times to achieve a better thrombus breaking effect.

[0081] Referring back to Figure 6a and Figure 6b in combination with Figure 3 It is also because of the structure design of the second capture unit 1312 that the circumferential part is locally turned outward and bent, which further improves the flexibility of the entire device, so that it can better work in tortuous blood vessels and variable diameter blood vessels. The specific number of the second capture unit 1312 is not limited, although four second capture units 1312 are shown in the figure, but in other embodiments, more or less than four second capture units 1312 (such as two second capture units 1312, three second capture units 1312, five second capture units 1312 or six second capture units 1312, etc.) can be included. The second capture unit 1312 is preferably arranged in pairs, so that the second capture mesh surface 1312a of the adjacent two second capture units 1312 can present a circumferentially complete arrangement state in the circumferential direction of the support member 110, that is, a circumferentially complete umbrella surface. This arrangement can better intercept and break the thrombus and improve the thrombus removal effect, see Figure 4a and Figure 4b .

[0082] As Figure 4a and Figure 4bAs shown, in the embodiment, the second capturing net surfaces 1312a of the two adjacent second capturing units 1312 are arranged in a staggered manner in the circumferential direction of the support member 110, so that the second capturing net surfaces 1312a of the two second capturing units 1312 can be combined to form a complete umbrella surface in the circumferential direction of the support member 110, which not only can effectively intercept and capture the thrombus, but also can increase the flexibility and adaptability of the device in the tortuous blood vessels and the variable-diameter blood vessels, reduce the possibility of excessive deformation and inward collapse of the net-shaped capturing unit 131 in the curved blood vessels, and also can reduce the resistance when withdrawing into the catheter, thereby facilitating the delivery and recovery.

[0083] Then, referring to Figure 6b , if the second capturing unit 1312 is orthogonally projected from the distal end to the proximal end, in an embodiment, it can be seen that the outermost projection line L of the second capturing net surface 1312a of the second capturing unit 1312 forms an arc angle of 180° with respect to the center of the second capturing unit 1312, but the arc angle is not limited to this. In other embodiments, the arc angle of the outermost projection line L of the second capturing net surface 1312a can be greater than or less than 180°, as long as the second capturing net surfaces 1312a of the two second capturing units 1312 can form a complete umbrella surface in the circumferential direction of the support member 110. The bending angle of the second capturing net surface 1312a of the second capturing unit 1312 can be any suitable angle. In summary, the arc angle of the outermost projection line L of the second capturing net surface 1312a of the second capturing unit 1312 is less than 360°.

[0084] Further, during the operation, the medical device 100 needs to enter the body with the help of the delivery device 300, so the delivery device 300 is used to load the medical device 100 and deliver the compressed medical device 100 to the target lesion. Of course, the delivery device 300 has other functions in addition to delivering the medical device 100, such as controlling the release and recovery of the medical device 100. During the thrombectomy, the suction device 500 is often used to suck the thrombus into and out of the body to ensure the efficiency and effect of thrombectomy. Therefore, the suction device 500 is used to suck the thrombus captured by the medical device 100, and the suction device 500 can be detachably or non-detachably connected with the delivery device 300, and the suction device 500 is suitable for applying suction force through the delivery device 100 to suck the thrombus at the target lesion. Here, those skilled in the art can also understand the structure and function of the delivery device 300 and the suction device 500 according to the prior art, and the present application does not make a detailed description.

[0085] In the embodiment shown, the mesh capture device 130 is of a split design, in which case the flat loading segments 131a of each capture unit 131 are generally cylindrical in shape, and each of these flat loading segments 131a can be fitted over the outer peripheral surface of the distal end of the support member 110, and then the flat loading segment 131a is fixedly connected to the support member 110. The connection between the flat loading segment 131a and the support member 110 can be achieved in many ways, and at least one of these ways can be selected for implementation. The following is a demonstrative explanation,

[0086] The flat loading segment 131a of the capture unit 131 and the support member 110 can be connected by means of heat staking, glue bonding or mechanical connection, and the mechanical connection can be any connection known to those skilled in the art, including but not limited to welding. In this embodiment, the flat loading segment 131a of the capture unit 131 and the support member 110 are fixedly connected by means of the visualization ring 120, which is fitted over the outside of the flat loading segment 131a, and then the proximal end of the flat loading segment 131a is clamped and fixed to the outer peripheral surface of the support member 110. The visualization ring 120 is made of a material that is not radiopaque, and the specific material is not required. The visualization ring 120 is used to identify the position of the proximal end 131d of the capture unit 131.

[0087] The capture unit 131 is a self-expanding mesh structure, which is in a compressed state under the action of an external force, and automatically changes from the compressed state to the expanded state after the external force is removed. The capture unit 131 is in a natural state when there is no external force, and the capture unit 131 in the natural state is in the expanded shape. The capture unit 131 is compressed and loaded into the delivery device 300 to present the compressed state, and generally, the capture unit 131 is compressed into a substantially linear and substantially parallel to the support member 110 extending compressed shape, that is, the capture unit 131 is inverted when compressed, and the umbrella surface is substantially collinear with the flat loading segment 131a, and the delivery size is small. After being released from the constraint of the delivery device 300, the capture unit 131 can automatically expand to the expanded state. The capture unit 131 can be converted between the compressed state and the expanded state.

[0088] The capture unit 131 is usually made of a metal material, such as a metal or alloy material, and is particularly preferred to have a shape memory effect, including but not limited to a nickel-titanium alloy. Here, the metal mesh tube can be prepared by various means known in the art, and the metal mesh tube is then shaped to form the capture unit 131 in which the flat loading segment 131a and the capture mesh surface are integrated together. As well known in the field of heat setting, a mold can be used to hold the metal mesh tube in its desired final configuration and subjected to appropriate heat treatment, so that the capture unit 131 is shaped to the desired configuration.

[0089] In some embodiments, the capturing units 131 are integrally cut from metal tubes, and the cutting method is not limited to laser cutting. In other embodiments, the capturing units 131 are integrally woven from a plurality of metal wires, and the weaving method is not particularly limited. In the present embodiment, the first capturing unit 1311 and the second capturing unit 1312 are each integrally cut from a metal tube having a shape memory effect and then heat treated to be shaped, so that the capturing units 131 have good radial support, and the outwardly curved capturing net surface further ensures the flexibility and adaptability of the capturing units 131, which reduces damage to the blood vessel wall, better scrapes, captures and transfers thrombus, and also reduces the withdrawal resistance when accommodated into the delivery device.

[0090] The number of capturing units 131 can be determined according to the length of the lesion (such as the length of the thrombus) and the length of the thrombus captured by the capturing units 131. Taking the thrombus as an example, in order to achieve rapid removal of a large amount of thrombus, generally one first capturing unit 1311 and more than two second capturing units 1312 are provided, and each capturing unit 131 can segmentally bring the thrombus out of the body; if it is suitable for the removal of a small amount of thrombus, only one first capturing unit 1311 and two second capturing units 1312 can be provided. The length and radial size of the capturing units 131 can be the same or different.

[0091] The present application does not limit the shape of the mesh holes 131e of the capturing units 131, and the mesh holes 131e can be in any suitable shape, such as: rhombus, rhomboid, rectangle, circle, ellipse or other shapes. In some embodiments, the mesh holes 131e of the flat loading segment 131a are substantially rhombic or rhomboid, and the shape of the mesh holes 131e of the capturing net surface is not limited, and as some options, the mesh holes 131e of the capturing net surface can be one or a combination of rectangular, circular, rhombic, elliptical, etc.

[0092] The mesh hole density of the flat loading segment 131a is substantially uniform, and the mesh hole density of the capturing net surface gradually changes during the outwardly curved process of the capturing net surface, which makes the mesh hole density of the capturing net surface gradually sparse from the center to the edge, forming a mesh hole dense area near the center and a mesh hole sparse area away from the center on the capturing net surface. Referring to Figure 6b Taking the second capturing unit 1312 as an example, the mesh hole density of the second capturing net surface 1312a of the second capturing unit 1312 gradually becomes sparse in the direction R from the center to the edge. The number of mesh holes in the mesh hole dense area is greater than that in the mesh hole sparse area, and the size (pore size) of the mesh holes in the mesh hole dense area is smaller than that in the mesh hole sparse area. The mesh hole dense area is conducive to collecting thrombus and reducing the probability of thrombus escaping to the distal branch, and the mesh hole sparse area is conducive to breaking large thrombus during the outwardly curved process of the capturing unit 131 or the withdrawal process. At the same time, the arrangement of the mesh holes which are dense in the center and sparse at the edge can better hold the thrombus and also reduce the sheath accommodation resistance.

[0093] In actual use, the radial dimension of the at least one capturing unit 131 when fully deployed is greater than or equal to the diameter of the blood vessel in which the lesion is located, which allows the capturing net surface of the capturing unit 131 to effectively scrape and collect the thrombus attached to the vessel wall and also move along the inner wall of the blood vessel, so that the fragmented thrombus can be collected into the umbrella-shaped capturing net surface during the withdrawal process, while the blood flow can also pass through the capturing net surface of the capturing unit 131, which also ensures the smooth flow of blood and guarantees the safety of the patient. When the capturing unit 131 is fully deployed, the maximum diameter or the diameter at other positions on the capturing net surface can be greater than or equal to the diameter of the blood vessel in which the lesion is located.

[0094] Referring to Figures 1 to 3 The distal end of the support member 110 is provided with a distal guide head 111, and the distal surface of the distal guide head 111 is smooth and hardly damages the surrounding tissue. The presence of the distal guide head 111 facilitates the advancement of the medical device 100 in the lumen. The distal guide head 111 can be a hollow conical cap with a spherical end surface at the distal end, and a step is formed at the junction of the conical cap and the support member 110, which can abut against the distal end surface of the delivery catheter 302 of the delivery device 300 without entering the lumen of the delivery catheter 302. In practice, the support member 110 can be operated to push the medical device 100 out of the delivery device 300 for release, and if the release position of the medical device 100 is not appropriate, the medical device 100 can be retracted into the delivery device 300, and after the position is adjusted, the medical device 100 can be released again. After the thrombus is removed, the support member 110 can be operated to retract the medical device 100 into the delivery device 300, and then the thrombus can be guided out of the body.

[0095] In an embodiment, the support member 110 further comprises a hollow inner core. The hollow inner core preferably has an elastic zone and a rigid zone arranged axially from distal to proximal, and the elastic zone is softer than the rigid zone. The elastic zone is used to mount the mesh capturing device 100. The elastic zone and the rigid zone can be integrally formed or separately formed and then assembled, such as separate connection, and the distal end of the rigid zone and the proximal end of the elastic zone can be connected by heat welding, clamping or other known means, which is not limited in the present application. The rigid zone is beneficial to force transmission, and the elastic zone can freely stretch and bend with the bending of the capturing unit 131, thereby improving the flexibility and applicability of the medical device 100 in tortuous blood vessels and variable-diameter blood vessels. In other embodiments, the entire hollow inner core can also adopt a rigid zone.

[0096] As Figures 1 to 3As shown, the delivery device 300 generally includes a sheath 301 and a delivery catheter 302 arranged coaxially from the outside to the inside. A support member 110 extends through the delivery catheter 302. The delivery catheter 302 compresses and carries all the capture units 131 to the lesion site. The delivery catheter 302 also extends through the sheath 301 and is pushed within it. After thrombectomy, the medical device 100 can be retrieved into the sheath 301. The proximal end of the sheath 301 needs to be sealed with a sealing valve to prevent blood leakage from the proximal end of the sheath 301.

[0097] like Figure 1 As shown, the aspiration device 500 includes an aspiration tube 501 and a connecting seat 502. Further, the aspiration device 500 also includes an aspiration apparatus (not shown). The connecting seat 502 is detachably mounted on the proximal end of the delivery catheter 302. A flexible hemostatic sealing valve 503 is typically provided at the proximal opening of the connecting seat 502 to seal the proximal end of the connecting seat 502. The proximal end of the delivery catheter 302 is connected to the connecting seat 502 to form a main channel through which the medical device 100 enters and exits the delivery catheter 302. The aspiration tube 501 is located on the side of the connecting seat 502, and its distal end is connected to a side hole of the connecting seat 502. A one-way valve 504 is typically provided on the proximal end of the aspiration tube 501. The one-way valve 504 is used to connect the aspiration apparatus, which applies suction force to the delivery catheter 302 through the aspiration tube 501. The suction device can be selected from any possible fluid delivery device, such as a vacuum pump.

[0098] Given that some thrombi are old and tightly adhered to blood vessels, the capture unit 131 struggles to scrape or embed them. To address this issue, in one embodiment, the delivery catheter 302 is provided with multiple micropores through which thrombolytic agents can be released, dissolving the thrombi. These micropores can be uniformly or non-uniformly arranged along the axial direction of the delivery catheter 302, or uniformly or non-uniformly arranged along its circumference, or distributed in both the axial and circumferential directions. In this case, the thrombolytic agent can partially dissolve or soften the thrombi it contacts, increasing the efficiency of the capture unit 131 in scraping and embedding the thrombi, thereby improving the success rate of thrombectomy for old thrombi. In other embodiments, a thrombolytic drug is sprayed onto the capture mesh surface of the capture unit 131. The drug can be crystalline and coated on the capture mesh surface for rapid release. During deployment, the outwardly curved capture mesh of the capture unit 131 wraps around the thrombus, and the mesh surface contacts the blood vessel wall. After a period of time, the thrombolytic drug partially dissolves or softens the contacted thrombus, thereby increasing the efficiency of scraping and embedding the thrombus. The medical device is then retracted, improving the success rate of thrombectomy for old thrombi. Here, the microporous release of the thrombolytic drug and the spraying of the thrombolytic drug onto the capture unit 131 can be performed simultaneously or selectively.

[0099] Next, combine Figures 7a to 7f The process of using the medical system 100 will be further explained, with the example of removing a thrombus from a blood vessel.

[0100] like Figure 7a As shown, when it is necessary to remove a thrombus from the lesion site of a blood vessel, the guide wire 10 is first pushed along the blood vessel 20 to the thrombus 30, and the guide wire 10 is continued to be pushed so that it completely passes through the thrombus 30.

[0101] like Figure 7b As shown, the sheath 301 is pushed along the guidewire 10 to a position close to the thrombus 30. Then, keeping the position of the sheath 301 unchanged, the delivery catheter 302 carrying the medical device 100 is also pushed along the guidewire 10 until the distal guide head 111 at the distal end of the support member 110 completely passes through the thrombus 30.

[0102] like Figures 7c to 7e As shown, the support member 110 is then kept stationary, and the delivery catheter 302 is gradually retracted until the multiple capture units 131 have fully expanded and deployed in sequence. At this point, the capture mesh of each capture unit 131 will fully embed and break the thrombus 30. Then, the aspiration device is activated, which can draw the thrombus at the distal opening 301a of the sheath 301 into the lumen of the delivery catheter 302 and into the aspiration tube 501.

[0103] like Figure 7fAs shown, after all the capture units 131 are deployed, the support member 110 is retracted proximally, so that all the capture units 131 are also slowly moved proximally, the thrombus 30 is gradually scraped, squeezed, cut and broken, and blocked between the capture mesh surface of the capture unit 131 and the adjacent capture unit 131, and gradually moved to the vicinity of the distal opening 301a of the sheath tube 301, and in this process, the thrombus 30 is continuously aspirated using the suction device, until the last capture unit 131 at the distal end is retracted into the sheath tube 301, at this time, part of the thrombus will be collected in the sheath tube 301, and finally withdrawn out of the body together with the medical device 100.

[0104] Preferably, the mesh density of the plurality of capture units 131 gradually decreases from the distal end to the proximal end, which makes the capture unit 131 at the proximal end have relatively sparse mesh 131e, which is beneficial to break large thrombus, and the capture unit 131 at the distal end has relatively dense mesh 131e, which is beneficial to intercept small thrombus from escaping to the distal end. However, in other embodiments, the mesh density of the plurality of capture units 131 can be the same.

[0105] <Embodiment Two>

[0106] Please refer to Figure 8 , the structure of the capture unit 131 provided by the second embodiment of the present application is basically the same as that of the capture unit 131 provided by the first embodiment, and the same parts will not be described again, and only the different points will be described below.

[0107] As Figure 8 shown, different from the first embodiment, in the first capture unit 1311 provided by the second embodiment, a film 1314 is arranged on the first capture mesh surface 1311a of the first capture unit 1311, and the film 1314 covers part of the mesh holes 131e of the first capture mesh surface 1311a. Preferably, the film 1314 only covers the mesh sparse area of the first capture mesh surface 1311a, and the mesh dense area of the first capture mesh surface 1311a is not covered by the film. The presence of the film 1314 can make the first capture unit 1311 better collect and block the broken thrombus that escapes, improve the thrombectomy effect, and at the same time maintain the smooth blood flow in the lumen. The film 1314 can be arranged on the inner surface or the outer surface of the first capture mesh surface 1311a. The film 1314 can be sewn and fixed on the first capture mesh surface 1311a, or fixed on the first capture mesh surface 1311a in other possible suitable ways.

[0108] <Embodiment Three>

[0109] Please refer to Figure 9a and Figure 9b , the structure of the capture unit 131 provided by the third embodiment of the present application is basically the same as that of the capture unit 131 provided by the first embodiment, and the same parts will not be described again, and only the different points will be described below.

[0110] As Figure 9a and Figure 9b different from the embodiment one, the embodiment three provides the capturing unit 131, in which the mesh supporting rods 131f of the capturing net surface of the capturing unit 131 are provided with the developing elements 1315, which can be developed under X-ray. Thus, during the operation, the operator can observe the position and the unfolding of the capturing unit 131 in the lumen according to the developing elements 1315 in real time. In the illustrated embodiment, the first capturing unit 1311 is taken as an example for illustration, but in fact, the second capturing unit 1312 can also be provided with the developing elements 1315 in the same way.

[0111] The developing elements 1315 are preferably provided at the maximum radial position after the unfolding of the capturing net surface, so as to facilitate the observation of the wall-adhesion of the capturing net surface. The developing elements 1315 are preferably a plurality of developing elements 1315 arranged on the same circumference. However, those skilled in the art should recognize that the developing elements 1315 can actually be provided at any suitable position on the capturing net surface, and can be distributed at different positions on the capturing net surface, and the present application does not limit this. The present application also does not have special limitations on the way of providing the developing elements 1315 on the capturing net surface, and those skilled in the art can select at least one structure to implement. The following is described exemplarily.

[0112] In an embodiment, as Figure 9b shown, the developing element 1315 includes a mounting rod 13151 and a developable body 13152 provided on the mounting rod 13151. The mounting rod 13151 is provided in the mesh hole 131e, one end of the mounting rod 13151 is connected with the mesh supporting rod 131f, and the other end of the mounting rod 13151 is a free end. The developable body 13152 can be implemented in any possible developing structure, for example, a developing wire, a developing ring, etc. In the illustrated embodiment, the developable body 13152 adopts a developing wire, which is spirally wound on the mounting rod 13151. The mounting rod 13151 can be integrally formed with the mesh tube, such as integrally cut and formed, which is convenient for manufacturing. The material for preparing the developable body 13152 is a conventional radiopaque material, including but not limited to platinum-iridium alloy, tungsten, etc. The developable body 13152 can be fixedly connected with the mounting rod 13151 in various ways, for example, by welding, adhesive bonding or clamping, etc. In other embodiments, the developing element 1315 can be replaced by a developing structure made of a composite core wire (such as DFT), which includes a nickel-titanium sleeve and a developing core wire covered by the nickel-titanium sleeve.

[0113] It should be noted that although the present embodiment is described by taking the installation rod 13151 and the developable body 13152 as examples, this does not constitute a limitation to the present application as understood by those skilled in the art, and in other embodiments, the developing element 1315 can also be directly prepared from a developing sleeve or a developing wire, which is directly sleeved or wound on the mesh support rod 131f.

[0114] <Embodiment Four>

[0115] Please refer to Figures 10a to 10b , Figures 11a to 11b , Figures 12a to 12c and to Figures 13a to 13b , the structure of the capturing unit 131 provided by Embodiment Four of the present application is basically the same as that of the capturing unit 131 provided by Embodiment One, and the same parts will not be described again, and only the different points will be described below. It should be noted that all the figures are simple schematic diagrams of the capturing unit 131, which only show the outline of the capturing unit 131 without showing the mesh shape in detail.

[0116] Different from Embodiment One, in the capturing unit 131 provided by Embodiment Four, the capturing mesh surface can present different bending angles and bending shapes.

[0117] In the present embodiment, the first capturing mesh surface 1311a and the second capturing mesh surface 1312a each include a head end 131c and a tail end 131b which are oppositely arranged in the axial direction of the capturing mesh surface, the head end 131c is bent towards the proximal end, and the tail end 131b is bent towards the head end 131c.

[0118] As Figure 10aAs shown, in an exemplary embodiment, the first capturing net surface 1311a of the first capturing unit 1311 comprises a first net surface Al and a second net surface A2 arranged in sequence from inside to outside, and the first net surface Al and the second net surface A2 are directly connected, where the first net surface Al constitutes the head end 131c of the first capturing net surface 1311a, and the second net surface A2 constitutes the tail end 131b of the first capturing net surface 1311a. When the first capturing unit 1311 is fully deployed, the first net surface Al bends towards the proximal end 131d of the first capturing unit 1311, and the second net surface A2 bends towards the first net surface Al, which makes the end of the tail end 131b of the first capturing unit 1311 be retracted into the umbrella-shaped first capturing net surface 1311a and towards the first net surface Al. At this time, in the process of retraction, the second net surface A2 shares a considerable part of the resistance of retraction, thereby reducing the possibility of the curled net surface turning up distally due to excessive thrombus, and making the first capturing net surface 1311a of the first capturing unit 1311 less likely to deform. In the embodiment shown, the first net surface Al of the first capturing unit 1311 is an arc-shaped net surface, and the second net surface A2 of the first capturing unit 1311 is also an arc-shaped net surface, and the first net surface Al and the second net surface A2 are oppositely arranged in the thrombus extraction direction, which corresponds to the axial direction of the first capturing unit 1311.

[0119] As shown, Figure 10b Similarly to the first capturing unit 1311, the second capturing net surface 1312a of the second capturing unit 1312 can also comprise a first net surface Al and a second net surface A2 arranged in sequence from inside to outside, and the first net surface Al and the second net surface A2 are directly connected, where the head end 131c of the second capturing unit 1312 is constituted by the first net surface Al, and the tail end 131b of the second capturing unit 1312 is constituted by the second net surface A2. When the second capturing unit 1312 is fully deployed, the first net surface Al bends towards the proximal end 131d of the second capturing unit 1312, and the second net surface A2 bends towards the first net surface Al, which makes the end of the tail end 131b of the second capturing unit 1312 be retracted into the umbrella-shaped second capturing net surface 1312a and towards the first net surface Al. Accordingly, in the process of retraction, the second net surface A2 of the second capturing unit 1312 shares a considerable part of the resistance of retraction, thereby reducing the possibility of the curled net surface turning up distally due to excessive thrombus, and making the second capturing net surface 1312a of the second capturing unit 1312 less likely to deform. In the embodiment shown, the first net surface Al of the second capturing unit 1312 is an arc-shaped net surface, and the second net surface A2 of the second capturing unit 1312 is also an arc-shaped net surface, and the first net surface Al and the second net surface A2 of the second capturing unit 1312 are oppositely arranged in the thrombus extraction direction.

[0120] As shown, Figure 11aAs shown, in another exemplary embodiment, the first capturing mesh surface 1311a of the first capturing unit 1311 is composed of a combination of an arc-shaped mesh surface and a polygonal mesh surface. Specifically, the first mesh surface A1 of the first capturing unit 1311 is an arc-shaped mesh surface, while the second mesh surface A2 is a polygonal mesh surface. The first mesh surface A1 and the second mesh surface A2 are smoothly connected. Figure 11b As shown, similar to the first capture unit 1311, in other embodiments, the second capture mesh 1312a of the second capture unit 1312 can also be composed of an arc-shaped mesh and a polygonal mesh, wherein the first mesh A1 of the second capture unit 1312 is an arc-shaped mesh, the second mesh A2 is a polygonal mesh, and the first mesh A1 and the second mesh A2 are smoothly connected.

[0121] It should be understood that the main function of the second mesh surface A2 is to improve the support and interception performance of the capture mesh surface. At this time, the capture unit 131 has better support and interception performance, thus achieving a better removal effect. The mesh density of the tail end 131b and the mesh density of the head end 131c can be the same or different. Preferably, the tail end 131b has a sparser mesh density than the head end 131c, so that the tail end 131b cuts and breaks up and intercepts thrombi on the proximal side of the capture mesh surface, while the head end 131c further intercepts thrombi on the distal side of the capture mesh surface. Thus, during the retraction process, the larger mesh 131e of the tail end 131b can cut and break up large thrombi, while the relatively dense mesh 131e of the head end 131c can intercept small thrombi from escaping.

[0122] like Figure 12a and Figure 12b As shown, after full deployment, the tail end 131b of the first capture unit 1311 preferably curls outward to form a damage-resistant end 131g (not limited to a ring). The degree of curling of the damage-resistant end 131g can be set as needed, such as one or more turns or less than one turn. The provision of the damage-resistant end 131g can reduce the damage to blood vessels caused by the tail end 131b of the first capture unit 1311 during self-expansion deployment or retraction into the sheath 301. Preferably, a soft material 131h is provided at the end face of the damage-resistant end 131g. The soft material 131h is made of a relatively soft polymer material, which can further reduce the risk of damage to blood vessels by the tail end 131b. Figure 12c As shown, the second capture unit 1312 can be configured in the same way, such that the tail end 131b of the second capture unit 1312 is curled outward to form a damage-resistant end 131g, and a soft material 131h is further provided on the damage-resistant end 131g.

[0123] like Figure 13aAs shown, in other exemplary embodiments, the first capturing unit 1311, the first net surface A1 and the second net surface A2 are both fold line-shaped net surfaces, and the first net surface A1 and the second net surface A2 are connected through a transition net surface A3, which is an arc-shaped net surface. The transition net surface A3 realizes smooth transition between the fold line-shaped net surfaces. At this time, the first net surface A1 in fold line shape is used as the head end 131c, and the second net surface A2 in fold line shape is used as the tail end 131b, and the arc-shaped transition net surface A3 is in contact with the inner wall of the blood vessel for support. The support performance of the capturing net surface is good, and the contact area of the transition net surface A3 with the blood vessel is small, which can further reduce the damage to the blood vessel during the process of removing the thrombus. As shown in FIG. 13B, the first capturing unit 1311 can also be provided in other forms. For example, the first net surface A1 and the second net surface A2 can be connected through a transition net surface A3, which is a straight line-shaped net surface. The transition net surface A3 realizes smooth transition between the fold line-shaped net surfaces. At this time, the first net surface A1 in fold line shape is used as the head end 131c, and the second net surface A2 in fold line shape is used as the tail end 131b, and the straight line-shaped transition net surface A3 is in contact with the inner wall of the blood vessel for support. The support performance of the capturing net surface is good, and the contact area of the transition net surface A3 with the blood vessel is small, which can further reduce the damage to the blood vessel during the process of removing the thrombus. Figure 13b As shown, the second capturing net surface 1312a of the second capturing unit 1312 can also be similarly provided, and the specific description is not repeated here.

[0124] As can be seen from the above, the head end 131c of the first capturing unit 1311 and the second capturing unit 1312 can be an arc-shaped net surface or a fold line-shaped net surface, and the tail end 131b can also be an arc-shaped net surface or a fold line-shaped net surface.

[0125] However, the bending angle and bending shape of the capturing unit 131 are not limited to the cases listed in the above embodiments, and those skilled in the art can set the bending angle and bending shape of the capturing unit 131 according to actual needs. The bending angle and bending shape of the capturing net surface of the capturing unit 131 can be realized through different heat treatment shaping molds, and the net-shaped capturing device 130 can be composed of one or more of the above-mentioned various types of capturing units 131.

[0126] <Embodiment Five>

[0127] Please refer to Figure 14 The structure of the medical device 100 provided by the embodiment five of the present application is basically the same as that of the medical device 100 provided by the embodiment one, and the same parts are not described again. The following only describes the different points. It should be noted that, Figure 14 are simple schematic diagrams, which only show the outlines of all the capturing units 131 without showing the net-shaped form in detail.

[0128] As shown in FIG. 14B, the first capturing unit 1311 can also be provided in other forms. For example, the first net surface A1 and the second net surface A2 can be connected through a transition net surface A3, which is a straight line-shaped net surface. The transition net surface A3 realizes smooth transition between the fold line-shaped net surfaces. At this time, the first net surface A1 in fold line shape is used as the head end 131c, and the second net surface A2 in fold line shape is used as the tail end 131b, and the straight line-shaped transition net surface A3 is in contact with the inner wall of the blood vessel for support. The support performance of the capturing net surface is good, and the contact area of the transition net surface A3 with the blood vessel is small, which can further reduce the damage to the blood vessel during the process of removing the thrombus. Figure 14As shown, the medical device 100 provided by the fifth embodiment has a plurality of capture units 131 arranged in sequence at the distal end of the support member 110, wherein the first capture unit 1311 is one, and the second capture unit 1312 is four, and the second capture unit 1312 can present a complete umbrella surface in pairs. In addition, the radial size (corresponding to the diameter after complete expansion) of the mesh capture device 130 gradually decreases from the distal end to the proximal end, and at this time, the radial size of the distal-most first capture unit 1311 is preferably greater than or equal to the diameter of the diseased blood vessel, so that the distal-most first capture unit 1311 is in close contact with the inner wall of the blood vessel. It should be understood that the radial size of the complete umbrella surface presented by the second capture mesh surface 1312a of the adjacent two second capture units 1312 is considered as a whole, so that the radial size defined by the adjacent two second capture units 1312 changes in the axial direction of the support member 110.

[0129] The radial size gradually changing structure design is beneficial to reduce the resistance of the thrombus to the proximal capture unit 131 in the withdrawal process, and reduces the problem of excessive deformation or collapse of the proximal capture unit 131 in the withdrawal process due to excessive thrombus resistance. At the same time, the contraction deformation of the proximal capture unit 131 can be well buffered during withdrawal, and the loss of thrombus during recovery is reduced. In addition, the radial size gradually changing mesh capture device 130 can further increase its flexibility and adaptability in curved blood vessels and variable diameter blood vessels.

[0130] However, in other exemplary embodiments, the radial size of the mesh capture device 130 gradually increases from the distal end to the proximal end, and at this time, the radial size of the proximal-most second capture unit 1312 is preferably greater than or equal to the diameter of the diseased blood vessel, so that the proximal-most second capture unit 1312 is in close contact with the inner wall of the blood vessel. In this way, the mesh capture device 130 can also increase its flexibility and adaptability in tortuous blood vessels and variable diameter blood vessels, and especially the distal first capture unit 131 can be deep into the small diameter blood vessel (such as double lung branch) for thrombus removal, reducing the probability of blood vessel damage.

[0131] <Embodiment six>

[0132] Please refer to Figures 15a to 15c The structure of the medical device 100 provided by the sixth embodiment of the present application is basically the same as that of the medical device 100 provided by the first embodiment, and the same parts will not be described again. The following will only describe the different points.

[0133] As Figures 15a to 15cAs shown, in the medical device 100 provided by the sixth embodiment, the mesh capturing device 130 is designed as a whole or an integral type, such that the plurality of capturing units 131 are connected as a whole, i.e. the mesh capturing device 130 is assembled as a whole on the support member 110. The mesh capturing device 130 can be prepared by a net tube, such as being integrally woven and heat treated, or being integrally cut and heat treated.

[0134] In the present embodiment, the adjacent capturing units 131 are directly connected by the flat loading segment 131a, which is equivalent to that the adjacent capturing units 131 share the flat loading segment 131a. At this time, the second capturing mesh surface 1312a is directly formed by the net tube locally protruding outward in the radial direction, such that the second capturing mesh surface 1312a is similar to a mesh-shaped convex peak. In this case, preferably, the second capturing mesh surfaces 1312a of two adjacent second capturing units 1312 can present a circumferentially complete non-curved capturing mesh surface. Such a radially locally protruding second capturing mesh surface 1312a can increase the flexibility of the device, reduce the possibility of excessive deformation and inward collapse of the device in the curved blood vessel, so as to be suitable for tortuous blood vessels and variable-diameter blood vessels. In addition, such a design can also reduce the resistance when withdrawing into the catheter, facilitating transportation and recovery.

[0135] In the present embodiment, the second capturing mesh surface 1312a can have various suitable shapes, such as being defined by at least one shape or a partial shape of a spherical shape, a disc shape (including a disc-like shape), a cylindrical shape, a mesh basket shape and a mesh bag shape. Further, when the second capturing mesh surfaces 1312a of two adjacent second capturing units 1312 can present a complete capturing mesh surface in a circular or approximately circular shape, the supportability is better, which can effectively remove the thrombus in the blood vessel or scrape the thrombus attached to the blood vessel wall, and also can reduce the probability of excessive deformation or collapse of the capturing unit 131 due to excessive thrombus during the withdrawal process. Further, when the second capturing mesh surfaces 1312a of two adjacent second capturing units 1312 can present a complete capturing mesh surface in a mesh basket or mesh bag shape, the thrombus can be better collected and blocked from escaping to the distal end.

[0136] Similarly to the first embodiment, the second capturing mesh surface 1312a of the present embodiment can have an arc angle less than 360°, and preferably 180°.

[0137] Referring to Figures 15a to 15cAs shown, the mesh capturing device 130 can further include a third capturing unit 1313 having a third capturing mesh surface 1313a protruding radially outwardly in its entire circumference. Such a circumferentially fully protruding third capturing mesh surface 1313a can increase the supportability and the interception performance of the device. Such a third capturing mesh surface 1313a can be formed by the mesh tube protruding radially outwardly in its entire circumference. The third capturing mesh surface 1313a can also have various suitable shapes, defined by at least one of a spherical shape, a disc shape, a cylindrical shape, a mesh bag shape and a mesh basket shape. Further, the third capturing mesh surface 1313a can be deflected towards the proximal end or the distal end, which can reduce the resistance when retracting the third capturing unit 1313 into the sheath tube 302.

[0138] The first capturing unit 1311 to the third capturing unit 1313 each have very dense mesh holes 131e, and the radial dimension of at least one capturing unit 131 after full deployment is greater than or equal to the diameter of the diseased blood vessel, which can better scrape, collect and transfer small and broken thrombus. The shape, number and deployment diameter of the first to third capturing units can be set according to the use scene and the intraluminal situation, and the present application does not make specific limitations thereto.

[0139] As shown, Figure 15a In an exemplary embodiment, the number of the second capturing unit 1312 and the third capturing unit 1313 is two, and the two second capturing units 1312 are located between the two third capturing units 1313, but the actual number is not limited thereto. Among them, the second capturing unit 1312 is formed by a part of the disc shape (having a circular cross section), but the two second capturing units 1312 can present a complete disc-shaped capturing mesh surface, and the third capturing unit 1313 adopts a disc, and the mesh hole density of the second capturing unit 1312 and the third capturing unit 1313 is the same. After deployment, the radial dimension of the proximal-most third capturing unit 1313 is smaller than that of the other capturing units 131, and the distal-most first capturing unit 1311 can be in close contact with the blood vessel wall.

[0140] Compared with Figure 15a , Figure 15b the mesh hole density of the second capturing unit 1312 and the third capturing unit 1313 in the present application is not the same, and the mesh hole density of each capturing unit 131 gradually becomes sparse from the distal end to the proximal end, and the sparse mesh holes at the proximal end can better break large thrombus, and the dense mesh holes at the distal end can reduce the probability of thrombus escaping to the distal branch.

[0141] As shown, Figure 15cAs shown, in other exemplary embodiments, the third capturing unit 1313 can adopt a mesh basket, and the position of the mesh basket is not limited to that shown in the figure. The mesh basket-shaped third capturing unit 1313 can be further provided with a protruding rod 1313b located at the proximal side of the third capturing mesh surface 1313a. The protruding rod 1313b can cut a large thrombus when it is withdrawn, and at the same time collect the thrombus into the internal space of the third capturing mesh surface 1313a. This design combines the advantages of each capturing unit 131, and improves the thrombectomy effect.

[0142] Referring to Figures 15a to 15c As shown, the adjacent capturing units 131 are connected through the straight loading section 131a, the proximal end of the distal-most capturing unit 131 (corresponding to the first capturing unit 1311) is connected with the support member 110 and forms a distal connection point, and the proximal end of the proximal-most capturing unit (corresponding to the second capturing unit 1312 or the third capturing unit 1313) is connected with the support member 110 and forms a proximal connection point. The straight loading section 131a between the proximal connection point and the distal connection point of the mesh capturing device is not connected with the support member 110 to facilitate the smooth flow of blood. In the illustrated embodiment, the proximal end of the proximal-most second capturing unit 1312 or the third capturing unit 1313 is fixed by a visible ring 104, and the proximal end of the distal-most first capturing unit 131 is fixed by another visible ring 104.

[0143] <Embodiment Seven>

[0144] Different from the above-mentioned embodiments, the medical device 100 provided in the present embodiment is suitable for gallbladder or ureter stone removal, but the stone removal principle is basically similar to the thrombectomy principle.

[0145] In the present embodiment, after the capturing unit 131 is deployed, the capturing mesh surface thereof can be attached to the inner wall of the lumen at the stone site, so that during the operation, the stone in the lumen can be pulled out and collected in the capturing mesh surface by moving the capturing unit 131 for stone removal in the lumen. The dense mesh holes in the capturing mesh surface can effectively prevent small stones from passing through the mesh holes. In addition, the coaxial arrangement of the plurality of capturing units 131 forms a multi-layer stone removal structure, which can repeatedly clean the lumen and avoid missing stones, thereby improving the stone removal efficiency. On the other hand, in the stone removal process, the external suction equipment can be used to suck the small stones at the distal end into the catheter, thereby improving the stone removal rate.

[0146] In summary, the medical device and the medical system provided by the present application have at least the following beneficial effects:

[0147] Firstly, the first and second capturing units adopt an umbrella shape with distal opening curling outward, which has a small contact area with the lumen, and causes less damage to the lumen wall when removing the blockage such as thrombus or calculus. In the process of recovery, the capturing units can better collect the blockage, avoid the blockage from falling off or escaping, and better guide the capturing units into the delivery device.

[0148] Secondly, the distal opening of the distal-most first capturing unit curls outward as a whole, which is mainly used for intercepting broken blockages, while the distal opening of the remaining second capturing units curls outward partially. This structure design increases the flexibility and adaptability of the device in tortuous vessels and variable diameter vessels, thereby reducing the possibility of the device collapsing in the tortuous vessels or variable diameter vessels, and also reducing the resistance when withdrawing the catheter, facilitating delivery and recovery.

[0149] Furthermore, when the capturing mesh of each capturing unit is in close contact with the inner wall of the tube, the blockage attached to the tube wall can be effectively removed during the withdrawal process, especially for some blockages with old and strong attachment characteristics, which has better therapeutic effect. In addition, the blockage can also be collected in the curled umbrella-shaped capturing mesh, especially the space between adjacent capturing units can accommodate more blockages, improving the efficiency of removing the blockage. Further, the mesh density of each capturing unit gradually becomes sparse from distal to proximal, so that the relatively dense mesh at the distal end can collect and reduce the risk of blockage escaping to the distal branch, while the relatively sparse mesh at the proximal end can break large blockages during the withdrawal of the medical device, and wrap the blockage to transfer and deliver to the suction tube. Such a cleaning effect is good and the cleaning efficiency is high.

[0150] In addition, it should be recognized that although the present application has been disclosed as above with preferred embodiments, the above embodiments are not intended to limit the present application. For any skilled person in the art, many possible changes and modifications or equivalent embodiments of the above disclosed technical content can be made without departing from the scope of the present application. Therefore, any simple modification, equivalent change and modification of the above embodiments made according to the technical essence of the present application without departing from the content of the present application, all still belong to the scope of protection of the present application.

Claims

1. A medical device for removing an obstruction from a target lumen, comprising: The application relates to a support member and a net-like capturing device. The net-like capturing device comprises a plurality of capturing units arranged in sequence and at intervals along the axial direction of the support member, wherein the capturing units comprise first capturing units and a plurality of second capturing units, the first capturing units are farther away from the proximal end of the support member than the second capturing units, the first capturing units have first capturing net surfaces which are turned outward in the whole circumferential direction and bent towards the proximal end, the first capturing net surfaces are formed by heat setting treatment after turning outward of a part of the structure of a cutting net tube, the second capturing units have second capturing net surfaces which protrude outward in the radial direction in the partial circumferential direction, and the second capturing net surfaces of two adjacent second capturing units can present circumferentially complete capturing net surfaces. The second capturing net surfaces are formed by turning outward of the net tube in the partial circumferential direction and bending towards the proximal end, or the second capturing net surfaces are formed by protruding outward in the radial direction in the partial circumferential direction. The capturing units further comprise third capturing units, the first capturing units are farther away from the proximal end of the support member than the third capturing units, and the third capturing units have third capturing net surfaces which protrude outward in the radial direction in the whole circumferential direction. The third capturing net surfaces are formed by protruding outward in the radial direction in the whole circumferential direction of the net tube, and / or the third capturing net surfaces are deflected towards the proximal end or the distal end.

2. The medical device of claim 1, wherein, The capturing units are connected to each other as a whole, or the capturing units are not connected to each other and form separate units.

3. The medical device according to claim 1 or 2, characterized in that When the capturing units are connected to each other as a whole, the net-like capturing device is formed by one net tube, the adjacent capturing units are connected through flat loading segments, the proximal end of the distal end capturing unit is connected to the support member and forms a distal end connecting point, the proximal end of the proximal end capturing unit is connected to the support member and forms a proximal end connecting point, and the flat loading segment of the net-like capturing device between the proximal end connecting point and the distal end connecting point is not connected to the support member.

4. The medical device of claim 3, wherein, When the capturing units form separate units, the net-like capturing device is formed by a plurality of net tubes, and the net tubes correspond to the capturing units one by one, each capturing unit further has a flat loading segment which is fixedly sleeved on the distal end outer circumferential surface of the support member.

5. The medical device according to claim 1 or 2, characterized in that The second capturing net surfaces are formed by turning outward of the net tube in the partial circumferential direction and bending towards the proximal end, the first capturing net surfaces and / or the second capturing net surfaces comprise head ends and tail ends which are oppositely arranged in the axial direction, the head ends are bent towards the proximal end, the tail ends are bent towards the head ends, and the mesh density of the tail ends is sparser than that of the head ends.

6. The medical device of claim 5, wherein, The second capturing net surfaces are formed by turning outward of the net tube in the partial circumferential direction and bending towards the proximal end, the tail ends of the first capturing net surfaces and / or the second capturing net surfaces are curled to form damage-preventing end portions, and the damage-preventing end portions are wrapped by soft materials.

7. The medical device of claim 5, wherein, ​ 8. The medical device of claim 2, wherein, ​ 9. The medical device of claim 2, wherein, ​ 10. The medical device of claim 2, wherein, The second capturing net surface is formed by locally protruding the net tube circumferentially radially outward, and is defined by a partial shape of at least one of a spherical shape, a disc shape, a cylindrical shape, a mesh bag shape, and a mesh basket shape.

11. The medical device of claim 3, wherein, The third capturing net surface is defined by at least one of a spherical shape, a disc shape, a cylindrical shape, a mesh bag shape, and a mesh basket shape.

12. The medical device according to claim 1 or 2, characterized in that The medical device further satisfies at least one of the following conditions: The radial dimension of the at least one capturing unit after being fully deployed is greater than or equal to the diameter of the target lumen; The mesh density of the capturing net surface on at least part of the capturing unit gradually decreases from the center to the edge; The mesh density of the mesh capturing device gradually decreases from the near to the far; The radial dimension of the mesh capturing device gradually increases or decreases from the near to the far; The first capturing net surface is provided with a coating film, and the coating film covers part of the mesh holes of the first capturing net surface.

13. The medical device according to claim 1 or 2, characterized in that The support member comprises a hollow inner core and a distal guide head, the distal guide head is arranged at the distal end of the hollow inner core, the hollow inner core has a rigid region and an elastic region arranged from the near to the far in the axial direction, and the mesh capturing device is arranged on the elastic region.

14. A medical system, characterized by The medical device according to any one of claims 1-13; The delivery device is used for loading the medical device to deliver the medical device into the target lumen; And, The suction device is used for being connected with the delivery device and applying suction force through the delivery device to suck the blockage in the target lumen. ​

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