阅读说明：本技术 取栓装置以及介入医疗系统 (Thrombectomy device and interventional medical system ) 是由 龙平 于海瑞 于 2018-06-07 设计创作，主要内容包括：本发明提供一种取栓装置以及介入医疗系统,能够提高取栓效果和取栓效率,且不会对血管造成损伤。所述取栓装置包括至少一取栓支架、一个取栓滤网、推拉导丝和推拉管,所述取栓滤网位于取栓支架的远端,所述推拉管穿设在取栓支架中,并分别与取栓支架的近端以及取栓滤网的近端连接,所述推拉管具有两端开放的中空通道,所述推拉导丝以可活动的方式穿设于中空通道中,且所述推拉导丝的远端从中空通道的远端延伸出并与取栓滤网的远端连接,其中,所述推拉管用于与推拉导丝同轴相对移动,使取栓滤网的近端向内凹陷或向外伸长,以此调整取栓滤网的形态。所述介入医疗系统包括所述的取栓装置以及用于输送取栓装置的输送导管。(the invention provides a thrombus removal device and an interventional medical system, which can improve thrombus removal effect and thrombus removal efficiency and do not damage blood vessels. The thrombus taking device comprises at least one thrombus taking support, a thrombus taking filter screen, a push-pull guide wire and a push-pull tube, wherein the thrombus taking filter screen is positioned at the far end of the thrombus taking support, the push-pull tube is arranged in the thrombus taking support in a penetrating mode and is respectively connected with the near end of the thrombus taking support and the near end of the thrombus taking filter screen, the push-pull tube is provided with a hollow channel with two open ends, the push-pull guide wire is movably arranged in the hollow channel in a penetrating mode, and the far end of the push-pull guide wire extends out of the far end of the hollow channel and is connected with the far end of the thrombus taking filter screen, wherein the push-pull tube is used for moving relative to the push-pull guide wire in a coaxial mode, so that the near end of the thrombus taking filter screen is sunken inwards or outwards. The interventional medical system comprises the embolectomy device and a delivery catheter for delivering the embolectomy device.)

1. A thrombectomy device, comprising:

At least one embolectomy support;

The thrombus taking filter screen is positioned at the far end of the thrombus taking bracket;

The pushing and pulling pipe is arranged in the thrombus taking support in a penetrating mode and is respectively connected with the near end of the thrombus taking support and the near end of the thrombus taking filter screen, and the pushing and pulling pipe is provided with a hollow channel with two open ends; and

the push-pull guide wire is movably arranged in the hollow channel in a penetrating way, and the far end of the push-pull guide wire extends out of the far end of the hollow channel and is connected with the far end of the embolectomy filter screen;

the push-pull tube is used for coaxially and relatively moving with the push-pull guide wire, so that the proximal end of the thrombus removal filter screen is inwards sunken or outwards extended.

2. The embolectomy device of claim 1, wherein the push-pull tube and the push-pull guidewire move coaxially relative to one another to form a first environment and a second environment, and the embolectomy screen comprises a proximal portion and a distal portion;

said proximal portion being compressed to a concave state in said first environment, and extended to an elongated state in said second environment, and returning to an original state in a third environment;

The mesh of the proximal portion in the depressed state is larger than the mesh of the proximal portion in the original state, and the mesh of the proximal portion in the elongated state is smaller than the mesh of the proximal portion in the original state.

3. The embolectomy device of claim 2, wherein the diameter of the embolectomy screen in the first environment is greater than or equal to the diameter of the embolectomy screen in the third environment, and the diameter of the embolectomy screen in the second environment is less than the diameter of the embolectomy screen in the third environment.

4. The embolectomy device of any of claims 1-3, wherein the density of the mesh of the embolectomy screen is greater than the density of the mesh of the embolectomy support.

5. the embolectomy device of any of claims 1-3, wherein the embolectomy screen comprises a proximal portion and a distal portion, the mesh density of the proximal portion being less than or equal to the mesh density of the distal portion.

6. The embolectomy device of claim 5, wherein the mesh density of the proximal portion is 2-5 times the mesh density of the embolectomy stent and the mesh density of the distal portion is 5-20 times the mesh density of the embolectomy stent.

7. The embolectomy device of any of claims 1-3, wherein the distance between the distal end of the embolectomy screen and the proximal end of the embolectomy support is 5.0 mm.

8. The embolectomy device of any of claims 1-3, further comprising:

A plurality of development rings of making by development material set up respectively the near-end of embolectomy support, the near-end of embolectomy filter screen and the distal end of embolectomy filter screen.

9. The embolectomy device of any of claims 1-3, wherein the embolectomy screen is made of a shape memory material selected from the group consisting of a combination of one or more of metals and polymeric materials.

10. an interventional medical system, comprising:

A embolectomy device as defined in any of claims 1-9; and

a delivery conduit for delivering the thrombectomy device.

Technical Field

The invention belongs to the field of medical instruments, and particularly relates to a thrombus removal device and an interventional medical system.

Background

in China, acute stroke is the third leading cause of death and the first cause of disability. Statistically, about 200 million new stroke occur annually in the country, with ischemic stroke accounting for about 85% of all patients.

Once acute cerebral arterial thrombosis occurs, how to quickly remove thrombus blocking blood vessels is the key of successful treatment, and two conventional treatment methods are adopted, namely firstly, the thrombus is eliminated through thrombolytic drugs; second, the thrombus is removed by a mechanical thrombectomy device. The artery and vein thrombolysis is a conventional method for treating acute ischemic stroke, but the method has high requirement on the treatment time window, strictly requires that patients arrive at hospitals within 3-4.5 hours from illness to receive related treatment, has a plurality of limitations on medicaments, and has low blood vessel recanalization rate of the acute ischemic stroke caused by the most serious large blood vessel occlusion.

mechanical arterial thrombectomy devices have gained widespread attention because of the following advantages: the rapid recanalization, the lower bleeding rate and the prolongation of the time window of the stroke intervention, and particularly has satisfactory clinical effect on the acute ischemic stroke vascular recanalization caused by the occlusion of large blood vessels.

The existing intracranial thrombus removal devices usually adopt a net structure, but the thrombus removal devices have a plurality of problems to be solved, wherein one main problem is that the capture rate of small emboli is low, and the distal blood vessel is easy to be embolized again.

Chinese utility model patent CN206120404 discloses a bolt taking support with screen panel: the bracket is connected with the mesh enclosure through a guide wire, the movement of the mesh enclosure is controlled through the mesh enclosure guide wire, and after the bracket is subjected to thrombus removal, the mesh enclosure guide wire is pulled to enable the mesh enclosure to be matched with the bracket to block thrombus escaping to the far end; although the mesh enclosure can capture the escaping small emboli, the near end of the mesh enclosure is in an open state, blood vessels are easily damaged in the process of moving the mesh enclosure, and the mesh size of the mesh enclosure is uniform, so that the mesh enclosure cannot capture all the escaping small emboli. In addition, chinese utility model patent CN205597973 discloses a device is tied to bag form: the bag-shaped structure consists of a framework and a net, wherein the framework structure consists of a metal material or a high polymer material, and the net structure consists of a high polymer material and is provided with a microporous structure; the bag-shaped thrombus taking device is moved to enable the proximal end to cut thrombus and enable fallen emboli to enter the device; because the thrombus has adhesive force with the blood vessel, the thrombus can not be completely taken out by the method, and the reticular structure of the bag-shaped thrombus taking device fixes the reticular polymer membrane on the metal material by using the medical thread, and the polymer membrane is possibly damaged under the scouring of blood flow in the thrombus taking process, thereby influencing the thrombus taking effect. In addition, chinese utility model CN205885492 also has a similar bag-like structure. Further, chinese utility model patent CN107049420 discloses a stent embolectomy device with three closed-loop net units: the mesh area of the second closed-loop net unit positioned in the middle is larger than that of the first closed-loop net unit and the third closed-loop net unit positioned at the end parts, and because of the small mesh design of the far end and the near end, thrombus is not easy to displace and fall off in the withdrawing process; however, the design of the mesh holes with the size of the stent embolectomy device can not solve the problem that small emboli escape to cause embolism of a far-end blood vessel in the embolectomy process.

Therefore, the existing thrombus removal device cannot safely and effectively capture small thrombus which falls off in the thrombus removal process.

Disclosure of Invention

In view of this, the invention provides an embolectomy device and an interventional medical system, which can effectively capture small emboli that fall off in the embolectomy process, improve the embolectomy effect, and do not damage blood vessels.

according to one aspect of the present invention, there is provided a embolectomy device, comprising:

At least one embolectomy support;

The thrombus taking filter screen is positioned at the far end of the thrombus taking bracket;

the pushing and pulling pipe is arranged in the thrombus taking support in a penetrating mode and is respectively connected with the near end of the thrombus taking support and the near end of the thrombus taking filter screen, and the pushing and pulling pipe is provided with a hollow channel with two open ends; and

The push-pull guide wire is movably arranged in the hollow channel in a penetrating way, and the far end of the push-pull guide wire extends out of the far end of the hollow channel and is connected with the far end of the embolectomy filter screen;

the push-pull tube is used for coaxially and relatively moving with the push-pull guide wire, so that the proximal end of the thrombus removal filter screen is inwards sunken or outwards extended.

according to another aspect of the invention, an interventional medical system is provided, which comprises the embolectomy device and a delivery catheter for delivering the embolectomy device.

Preferably, the push-pull tube and the push-pull guide wire move coaxially and relatively to form a first environment and a second environment, and the embolectomy filter screen comprises a proximal end part and a distal end part;

said proximal portion being compressed to a concave state in said first environment, and extended to an elongated state in said second environment, and returning to an original state in a third environment;

the mesh of the proximal portion in the depressed state is larger than the mesh of the proximal portion in the original state, and the mesh of the proximal portion in the elongated state is smaller than the mesh of the proximal portion in the original state.

preferably, the diameter of the embolectomy screen in the first environment is greater than or equal to the diameter of the embolectomy screen in the third environment, and the diameter of the embolectomy screen in the second environment is less than the diameter of the embolectomy screen in the third environment.

preferably, the mesh density of the embolectomy screen is greater than the mesh density of the embolectomy support.

preferably, the embolectomy screen comprises a proximal portion and a distal portion, the mesh density of the proximal portion being less than or equal to the mesh density of the distal portion.

Preferably, the mesh density of the proximal part is 2-5 times of that of the embolectomy stent, and the mesh density of the distal part is 5-20 times of that of the embolectomy stent.

preferably, the distance between the far end of the embolectomy filter screen and the near end of the embolectomy support is 5.0 mm.

Preferably, the thrombus removal device further comprises:

A plurality of development rings of making by development material set up respectively the near-end of embolectomy support, the near-end of embolectomy filter screen and the distal end of embolectomy filter screen.

preferably, the embolectomy filter screen is made of a shape memory material selected from one or more of metal and polymer material.

Furthermore, according to the technical scheme provided by the invention, the thrombus removal device and the interventional medical system have the following beneficial effects:

Firstly, the proximal end of the embolectomy filter screen can be inwards sunken or outwards extended through the coaxial relative movement of the push-pull guide wire and the push-pull pipe, so that the mesh size on the proximal part of the embolectomy filter screen can be changed; when the near end of the embolectomy filter screen is sunken inwards to enlarge the meshes of the near end part, the fallen small emboli can smoothly enter the filter screen; when the proximal end of the embolectomy filter screen is stretched to reduce the meshes of the proximal part, the small embolus can be prevented from escaping again; in the process of deformation of the proximal end of the embolectomy filter screen, the mesh size of the embolectomy filter screen can be increased or decreased, so that the embolectomy filter screen can capture all small emboli escaping from the embolectomy support, and the embolectomy effect is improved;

Secondly, by utilizing the deformation of the thrombus taking filter screen, the diameter of the proximal end of the thrombus taking filter screen is increased while the proximal end of the thrombus taking filter screen is inwards sunken, so that the thrombus taking filter screen can better cling to the blood vessel wall in the process of capturing small emboli, the small emboli are prevented from escaping from the periphery of the filter screen again, and thrombus is better captured;

Thirdly, the thrombus taking filter screen is axially extended and radially reduced in the retracting process by utilizing the deformation of the thrombus taking filter screen, so that the thrombus taking filter screen is favorably and smoothly recycled, and the thrombus taking efficiency is further improved;

And fourthly, the proximal end and the distal end of the thrombus taking filter screen are respectively connected with the push-pull tube and the push-pull guide wire, so that both ends of the thrombus taking filter screen are of a furled structure, blood vessels cannot be damaged in the process of pushing and pulling the thrombus taking filter screen to enable the proximal end to be inwards sunken or outwards extend, and the safety of the thrombus taking process is remarkably improved.

drawings

The drawings are included to provide a better understanding of the invention and are not to be construed as unduly limiting the invention. Wherein:

FIG. 1a is a schematic structural view of a thrombus removal device in a preferred embodiment of the present invention;

FIG. 1b is a schematic illustration of an thrombectomy device according to a preferred embodiment of the present invention being delivered into a blood vessel through a microcatheter;

FIG. 1c is a schematic illustration of the thrombectomy device released from the blood vessel after detachment of the microcatheter according to the preferred embodiment of the present invention;

FIG. 1d is a schematic view of the proximal end of the embolectomy screen of a preferred embodiment of the present invention being recessed;

FIG. 1e is a schematic view of a embolectomy screen of a preferred embodiment of the present invention capturing small emboli;

FIG. 1f is a schematic view of the proximal end of the embolectomy screen of a preferred embodiment of the present invention being extended outwardly.

In the figure:

The thrombus removal device comprises a thrombus removal device-100, a thrombus removal device body-110, a thrombus removal filter-111, a proximal end part-111 a, a distal end part-111 b, a thrombus removal support-112, a push-pull guide wire-120, a push-pull tube-130, a microcatheter-140, visualization rings-150, 160 and 170, thrombus-300, a big thrombus-301 and a small thrombus-302.

Detailed Description

The core idea of the invention is to provide a thrombus taking device, which comprises a thrombus taking device main body, a push-pull guide wire and a push-pull tube; the thrombus taking device main body comprises at least one thrombus taking bracket and a thrombus taking filter screen, and the thrombus taking filter screen is positioned at the far end of the thrombus taking bracket; the push-pull pipe penetrates through the thrombus taking support and is respectively connected with the near end of the thrombus taking support and the near end of the thrombus taking filter screen; the push-pull tube is provided with a hollow channel with two open ends, the push-pull guide wire is movably arranged in the hollow channel in a penetrating way, and the far end of the push-pull guide wire extends out of the far end of the hollow channel and is connected with the far end of the thrombus taking filter screen; the pushing and pulling pipe is used for coaxially and relatively moving with the pushing and pulling guide wire, so that the proximal end of the embolectomy filter screen is inwards sunken or outwards extended, and the shape of the embolectomy filter screen is adjusted.

specifically, when the near end of the embolectomy filter screen is inwards sunken, the meshes at the near end of the embolectomy filter screen are enlarged, so that small emboli falling from the embolectomy support can enter the embolectomy filter screen through the large meshes at the near end of the embolectomy filter screen under the flushing of blood flow, and then all small emboli to be fallen enter the embolectomy filter screen, the near end of the embolectomy filter screen is outwards extended, so that the meshes at the near end of the embolectomy filter screen are narrowed, and the small emboli captured cannot escape from the narrow meshes of the filter screen, so that the small emboli is firmly captured in the embolus taking filter screen by the embolus taking filter screen, and finally, the embolus taking device main body is withdrawn, so that the large and small emboli can be pulled out of the body, the problem of secondary emboli due to the escape of the small emboli is solved, and the embolus taking effect and the embolus taking efficiency are improved.

The embolectomy device and the interventional medical system provided by the invention are further described in detail with reference to the drawings and the specific embodiments. The advantages and features of the present invention will become more apparent from the following description. It is to be noted that the drawings are in a very simplified form and are not to precise scale, which is merely for the purpose of facilitating and distinctly claiming the embodiments of the present invention.

As used in the claims and this specification, the singular forms "a," "an," and "the" include plural referents unless the content clearly dictates otherwise. As used in this specification, the term "or" is generally employed in its sense including "and/or" unless the content clearly dictates otherwise.

As used in the claims and this specification, the terms "longitudinal" and "axial" generally refer to a direction parallel to the axis of the embolic filter screen, and "transverse" and "radial" generally refer to a direction perpendicular to the axis of the embolic filter screen. The terms "proximal" and "distal" refer to the end proximal to the operator's site, and "forward" and "distal" refer to the end distal from the operator's site.

Referring first to fig. 1a, which is a schematic structural view of an embolectomy device in a preferred embodiment of the present invention, as shown in fig. 1a, an embolectomy device 100 is provided in an embodiment of the present invention, and the embolectomy device 100 comprises an embolectomy device body 110, a push-pull guidewire 120 and a push-pull tube 130. Wherein, the embolectomy device body 110 further comprises an embolectomy filter 111 and an embolectomy support 112. The embolectomy filter 111 is located at the far end of the embolectomy support 112, and may be close to the embolectomy support 112 (i.e. there is no space between the far end of the embolectomy support 112 and the near end of the embolectomy filter 111), or may be located at a certain distance from the embolectomy support 112, preferably about 5.0mm, so as to ensure that the length of the embolectomy device is within a reasonable range, thereby ensuring the embolectomy effect and facilitating the transportation and operation of the embolectomy device. Specifically, when the distance between the proximal end of the embolectomy filter 111 and the distal end of the embolectomy support 112 is about 5.0mm, for a distal or tortuous blood vessel such as an intracranial blood vessel, the distance not only allows the blood flow to flush small emboli into the embolectomy filter 111, but also prevents the embolectomy support 112 and the embolectomy filter 111 from being too closely spaced and affecting each other, and the embolectomy filter 111 can capture the small emboli in time, so as to prevent the small emboli from flowing to other branch blood vessels and forming secondary emboli, and the volume of the embolectomy device body 110 is small, thereby facilitating transportation and operation. Here, the number of the embolectomy holders 112 is not limited to one, and may be a plurality of axially arranged ones. When the number of the thrombus removal supports 112 is plural, the thrombus removal supports may be arranged at no intervals or at intervals, and the thrombus removal filter 111 is arranged at the distal end of the most distal one of the thrombus removal supports 112.

in addition, the push-pull tube 130 is inserted into the embolectomy support 112, the proximal end of the embolectomy support 112 is connected with the outer surface of the push-pull tube 130, and the proximal end of the embolectomy screen 111 is also connected with the outer surface of the push-pull tube 130. In addition, the push-pull tube 130 has a hollow channel with two open ends, the push-pull guide wire 120 is movably inserted into the hollow channel, and the distal end of the push-pull guide wire 120 extends out from the distal end of the hollow channel and is connected with the distal end of the embolectomy filter 111.

Next, referring to fig. 1b to fig. 1f, fig. 1b is a schematic diagram of the thrombus removal device in the preferred embodiment of the present invention being delivered into a blood vessel through a microcatheter, fig. 1c is a schematic diagram of the thrombus removal device in the preferred embodiment of the present invention being released into the blood vessel after being detached from the microcatheter, fig. 1d is a schematic diagram of the proximal end of the thrombus removal screen in the preferred embodiment of the present invention being depressed inwards, fig. 1e is a schematic diagram of the thrombus removal screen of the thrombus removal device in the preferred embodiment of the present invention capturing small emboli, and fig. 1f is a schematic diagram of the proximal end of the thrombus removal screen in the preferred embodiment of the present invention being extended.

as shown in fig. 1b to 1f, the thrombectomy device 100 is delivered to the lesion site of the blood vessel through the microcatheter 140, and the specific delivery process includes:

Before the thrombus removal device 100 is sent into a blood vessel, the thrombus removal device 100 is loaded in the lumen of the microcatheter 140, and at the moment, the thrombus removal support 112 and the thrombus removal filter screen 111 are both compressed in the lumen of the microcatheter 140;

Then, as shown in fig. 1b, the microcatheter 140 is delivered to the position of the thrombus 300 blockage in the blood vessel 200, and the distal end of the thrombectomy stent 112 is positioned at the front end (i.e. distal end) of the thrombus 300, and the proximal end of the thrombectomy stent 112 is positioned at the end (i.e. proximal end) of the thrombus 300, so that the thrombus 300 is positioned in the middle of the thrombectomy stent 112 after the thrombectomy stent 112 is expanded, thereby better capturing the thrombus 300;

Then, as shown in FIG. 1c, the microcatheter 140 is withdrawn, and the embolectomy device 100 is released, such that the thrombus 300 is located in the middle of the embolectomy stent 112 after the embolectomy stent 112 is expanded, thereby capturing the large embolus 301 by the embolectomy stent 112, while the small embolus 302 generated flows into the blood and flows toward the distal embolectomy screen 111, and is captured by the embolectomy screen 111. Here, the large embolus 301 is larger in volume than the small embolus 302. Furthermore, the openings of the embolectomy screen 111 are generally smaller than the openings of the embolectomy support 112 so that the embolectomy screen 111 can capture small emboli 302 that escape from the embolectomy support 112.

as shown in fig. 1d to 1f, the operation process of capturing the small embolus 302 by the embolectomy screen 111 includes:

After the embolectomy device 100 is released, the push-pull guide wire 120 is fixed to be kept still, the push-pull tube 130 is pushed towards the distal end of the embolectomy device 100, the proximal part 111a of the embolectomy screen 111 is pushed by the push-pull tube 130 to be sunken inwards, the embolectomy screen 111 is attached to the inner wall of the blood vessel 200, and the mesh opening at the proximal part 111a is enlarged (i.e. the mesh opening area is enlarged), as shown in fig. 1 d;

Furthermore, as shown in fig. 1d and 1e, under the flushing of blood flow, the small embolus 302 penetrates through the large mesh of the proximal portion 111a and enters the interior of the embolectomy screen 111, and since the mesh of the distal portion 111b of the embolectomy screen 111 is smaller than that of the proximal portion 111a, the small embolus cannot escape from the distal end of the embolectomy screen 111, thereby confining the small embolus 302 to the interior of the embolectomy screen 111;

Then, as shown in fig. 1f, the push-pull guide wire 120 is still kept stationary, and the push-pull tube 130 is pulled towards the proximal end of the embolectomy device 100, so that the proximal end portion 111a of the embolectomy screen 111 is stretched outwards under the pulling of the push-pull tube 130, and the axial length of the embolectomy screen 111 is increased, and the diameter is decreased, for example, a structure similar to a cone is formed, however, under the pulling of the push-pull tube, the mesh at the proximal end portion 111a of the embolectomy screen 111 is narrower (the mesh area is decreased) compared with the mesh in the original state, which can effectively block the small embolus 302 from escaping again, and at the same time, the diameter of the embolectomy screen 111 is also decreased for facilitating the recycling;

finally, after the capture of the large and small thrombi is completed, the push-pull guide wire 120 and the push-pull tube 130 are withdrawn at the same time, the whole thrombus taking device 100 is recovered into the micro-catheter 140, and the thrombus taking device 100 is further recovered to the guide catheter together with the micro-catheter 140 to be withdrawn out of the body.

in order to more clearly understand the usage of the embolectomy device 100 of the present invention, the whole operation of the embolectomy device 100 will be schematically and additionally described below in conjunction with the treatment of lesions in intracranial blood vessels, but the embolectomy device of the present invention is not limited to the embolectomy of intracranial blood vessels, and may be intracardiac blood vessels, pulmonary blood vessels, cervical blood vessels, lower limb blood vessels, etc., and the embolectomy device of the present invention is particularly suitable for small, tortuous blood vessels.

specifically, when intracranial vascular intervention is performed: firstly, determining the position of intracranial vascular lesion by angiography, then leading a guide wire through the lesion position, further leading a micro catheter 140 along the guide wire to pass through the lesion position, guiding and conveying the micro catheter 140 to intracranial lesion blood vessels generally from femoral artery or brachial artery, then withdrawing the guide wire, guiding an embolectomy device 100 into the micro catheter 140 from outer sheath tube and conveying the embolectomy device to the vascular lesion position, pushing the embolectomy device 100 to the distal end of the micro catheter 140 by using a push-pull guide wire 120 and a push-pull tube 130, but ensuring that the distal end of a stent 112 is at the front end of a thrombus 300 and the proximal end of the stent 112 is at the tail end of the thrombus 300, then withdrawing the micro catheter 140, enabling an embolectomy filter screen 111 and an embolectomy stent 112 to be released successively and the thrombus to be positioned in the middle of the released embolectomy stent 112, and based on the self-expansion characteristic, the embolectomy filter screen 111 and the embolectomy stent 112 are converted to an expanded state under the action of blood temperature and are abutted against the inner wall of the, then, the push-pull guide wire 120 is fixed, the push-pull tube 130 is pushed at the same time, the mesh opening at the proximal part 111a of the embolectomy filter screen is enlarged, the small embolus 302 escaping from the embolectomy bracket 112 enters the embolectomy filter screen 111 through the large mesh opening at the dent of the proximal part 111a, then the push-pull tube 130 is retracted, the mesh opening at the proximal part 111a is slender compared with the original state, so as to prevent the small embolus 302 from escaping again, finally, the embolectomy device 100 is retracted until the embolectomy device 100 and the micro-catheter 140 are retracted into the guide catheter at the same time, and the embolectomy device 100 can be withdrawn from the human body as a whole, thereby completing the embolectomy operation.

Obviously, according to the embolectomy device 100 provided by the embodiment of the present invention, the size of the mesh at the proximal portion 111a of the embolectomy filter 111 can be changed by the coaxial relative movement of the push-pull guide wire 120 and the push-pull tube 130, i.e. the push-pull guide wire 120 is fixed, and the push-pull tube 130 moves axially relative to the push-pull guide wire 120; when the mesh openings at the proximal part 111a of the embolectomy filter screen are enlarged, the fallen small emboli can smoothly enter the filter screen; when the mesh openings at the proximal portion 111a of the embolectomy screen become smaller, the small emboli are prevented from escaping again. According to the thrombus taking structure, in the process of deformation of the proximal end of the thrombus taking filter screen, blood vessels cannot be damaged, and meshes of the thrombus taking filter screen can be increased or reduced, so that the filter screen can capture all escaping small emboli, the thrombus taking effect is improved, and the thrombus taking structure is simple in structure and convenient to operate. And utilize the deformation of getting the embolus filter screen for get the embolus filter screen and paste the vascular wall better at the in-process of catching little embolus, thereby catch the thrombus better, and get the embolus filter screen and radially dwindle at the axial extension of withdrawal in-process, be favorable to its recovery smoothly.

In this embodiment, the thrombectomy stent 112 is a self-expanding stent structure that can be compressed within a microcatheter or outer sheath for storage, and that can self-expand and return to its original state after detachment of the device. The thrombectomy stent 112 of the present embodiment has an approximately cylindrical shape without external force, so as to better abut against the inner wall of the blood vessel. The embolectomy stent 112 is mainly made of shape memory material selected from one or more of metal and polymer material, preferably nickel-titanium alloy, and the embolectomy stent 112 can be made by laser cutting or weaving. Further, the embolectomy stent 112 comprises a closed loop mesh structure formed by splicing curved lines or straight lines, in some embodiments, the shape of the mesh on the embolectomy stent 112 can be circular, square, diamond, olive or cone, in practice, the embolectomy stent 112 can comprise a closed loop mesh structure with different sizes or shapes, and the embolectomy stent 112 with good adherence can be obtained by reasonably arranging the mesh with different sizes or shapes.

in this embodiment, the proximal end of the thrombus removal stent 112 is closed after being folded, so as to facilitate the transportation and recovery of the thrombus removal stent 112, and in addition, the distal end of the thrombus removal stent 112 is preferably open, so that the transportation and recovery are facilitated, the circulation of blood flow is not affected, the blood vessel is not damaged, and the thrombus capture effect is better. In another embodiment, the proximal end of the embolectomy support 112 may also be a ramped opening, or may also be a circular open opening.

In this embodiment, the proximal end and the distal end of the embolectomy filter screen 111 are connected to the push-pull tube 130 and the push-pull guide wire 120, respectively, and have a shape structure similar to a balloon without being subjected to an external force, and both ends of the embolectomy filter screen are folded structures, so that the proximal end of the embolectomy filter screen 111 is not damaged in the process of inward sinking or outward extending by pushing and pulling, the safety of the embolectomy process is significantly improved, and the embolectomy filter screen 111 is convenient to transport and recover. The furling structure can be a closed structure or a slope-type opening. When the proximal end of the embolectomy filter screen 111 is a slope-type opening, the thrombus-embolectomy filter screen is conveniently matched with the embolectomy support 112 with the proximal end also being a slope-type opening, so that the whole embolectomy device 100 is convenient to convey and recycle.

in this embodiment, when the embolectomy filter 111 is not subjected to an external force, a fourth environment is defined. In the fourth environment, the embolectomy filter screen 111 is in a natural state. Further, the embolectomy screen 111 is preferably made of a shape memory material, the shape memory material can be selected from one or more combinations of metal materials and polymer materials, the metal is preferably nickel titanium alloy, and the embolectomy screen 111 can be made by laser cutting or weaving and the like.

further, the embolectomy filter screen 111 comprises a proximal part 111a and a distal part 111b from the near to the far, and the mesh density on the proximal part 111a is preferably less than or equal to the mesh density on the distal part 111b, and more preferably the mesh density at the proximal part 111a is less than the mesh density at the distal part 111b, so that under the cooperation of the push-pull guide wire 120 and the push-pull tube 130, the mesh size of the proximal part 111a of the embolectomy filter screen 111 can be adjusted more easily, and small emboli falling from the embolectomy support 112 can be captured more easily, and the small emboli can be prevented from escaping again to the far. Here, the mesh density refers to the degree of density of the mesh distribution, i.e., the number of meshes per unit area. That is, in the fourth environment, the mesh openings in the distal portion 111b of the embolectomy screen 111 are smaller or the same size as the mesh openings in the proximal portion 111a, and likewise, in the first, second or third environments, the mesh openings in the distal portion 111b are smaller or the same size as the mesh openings in the proximal portion 111 a. The mesh density of the proximal part 111a is preferably 2-5 times that of the embolectomy stent 112, and the mesh density of the distal part 111b is preferably 5-20 times that of the embolectomy stent 112. Thus, the mesh density of the embolectomy screen 111 is greater than the mesh density of the embolectomy support 112.

Further, the shape of the mesh on the embolectomy screen 111 is not particularly limited, but is preferably a polygon, and the polygon is not limited to a quadrangle. Furthermore, it should be understood that during withdrawal of the push-pull tube 130, the embolectomy screen 111 is generally elongated, and therefore, the mesh openings therein are not limited to deformation at the proximal portion 111a, but also propagate through the distal portion 111b, but the deformation of the distal portion 111b is substantially negligible relative to the proximal portion 111 a.

Preferably, the embolectomy device 100 further comprises visualization rings 150, 160, 170, wherein the visualization ring 150 is arranged at the proximal end of the embolectomy support 112 connected with the push-pull tube 130, another visualization ring 160 is arranged at the proximal end of the embolectomy screen 111 connected with the push-pull tube 130, and another visualization ring 170 is arranged at the distal end of the embolectomy screen 111 connected with the push-pull guide wire 120. And then the positions of the proximal end and the distal end of the thrombus removal support 112 are observed through X-ray visualization, so that whether thrombus is positioned in the middle of the thrombus removal support 112 when the thrombus removal support 112 is released can be judged, and the relative positions of the proximal end and the distal end of the thrombus removal filter screen 111 can be observed through visualization, so that the deformation state of the thrombus removal filter screen 111 can be judged, such as inward depression or outward extension. Any one of the developer rings is made of a developer material such as platinum, iridium, gold, tantalum, or alloys thereof. Further, the developing rings can be fixed at the respective connecting portions by welding, gluing, riveting or crimping.

Further preferably, the push-pull guide wire 120 is selected from medical guide wires, and the material is preferably stainless steel or nitinol, which can provide excellent pushing performance, operability and biocompatibility. The material of the push-pull tube 130 is preferably a polymer material to provide suitable pushing performance, operability and biocompatibility, and may be selected from Pebax, PTFE/PTE, silica gel, ABS resin, Kevlar fiber, glass fiber, phthalate, polyphenylene sulfide, N-butyl alcohol, styrene butadiene rubber, molybdenum trioxide, polyvinyl chloride, polystyrene, methyl acrylate, ethylene copolymer elastomer, epoxy resin glue, N-methylene bisacrylamide, dimethyl trimethylsilyl methylphosphonate, methyl methacrylate, isocyanate, nano graphene, o-hydroxybenzophenone, pitch-based carbon fiber, silicone rubber, hydroxyl silicone oil, etc.

Still further, an interventional medical system is provided in an embodiment of the present invention, which includes a delivery catheter and the embolectomy device 100, where the delivery catheter includes the microcatheter 140 of the embodiment for delivering the embolectomy device 100. Further, the delivery catheter further comprises a guiding catheter and a puncture sheath, the microcatheter 140 is used for entering the guiding catheter, the guiding catheter is used for entering the puncture sheath, and the puncture sheath firstly enters the blood vessel. In addition, the proximal end of the microcatheter is connected to the distal end of the outer sheath, and the thrombus removal device 100 can be pushed into the microcatheter by the push-pull guide wire 120 and the push-pull tube 130 to reach the thrombus site of the blood vessel. The sheath tube is a hollow polymer tube, and is mainly used for binding the thrombus removal device main body in product packaging, and is connected with the micro catheter through a connecting piece when the thrombus removal device is used, so that the thrombus removal device is guided into the matched micro catheter 140.

In summary, the push-pull tube 130 and the push-pull guide wire 120 of the present embodiment are matched with each other, so that the proximal portion 111a of the embolectomy screen 111 is recessed inwards, or the proximal portion 111a of the embolectomy screen 111 is stretched outwards, specifically, the push-pull tube 130 and the push-pull guide wire 120 move coaxially and relatively to each other to form a first environment and a second environment.

The conditions under which the first environment is created are: the push-pull wire 120 is kept stationary and the push-pull tube 130 is pushed towards the distal end of the embolectomy device 100. The conditions under which the second environment is created are: the push-pull wire 120 is held stationary and the push-pull tube 130 is withdrawn proximally of the thrombectomy device 100. Thus, the proximal portion 111a of the embolectomy screen 111 compresses to a concave state in the first environment, and elongates to an elongated state in the second environment, and also returns to the original state in the third environment. The conditions under which the third environment is created are: after the thrombus removal filter screen 111 is released, the thrombus is only restrained by the inner wall of the blood vessel.

Then, the mesh of the proximal end portion 111a in the depressed state is larger than the mesh of the proximal end portion 111a in the original state, and the mesh of the proximal end portion 111a in the elongated state is smaller than the mesh of the proximal end portion 111a in the original state. Therefore, by sizing the mesh of the proximal portion 111a, it is advantageous to capture small emboli, preventing them from escaping again.

Of course, the following effects can be obtained in addition to the above effects:

The diameter of the embolectomy screen 111 in the first environment is greater than or equal to the diameter of the embolectomy screen 111 in the third environment, and the diameter of the embolectomy screen 111 in the second environment is less than the diameter of the embolectomy screen 111 in the third environment. Therefore, in the process of withdrawing the embolectomy device, the diameter of the embolectomy filter screen 111 is favorably reduced by withdrawing the push-pull tube 130, so that the embolectomy filter screen can be better withdrawn, and the embolectomy efficiency is further improved.

Further, the diameter of the embolectomy screen 111 in the first environment is generally smaller than the diameter of the embolectomy screen 111 in the fourth environment, and therefore, the diameter of the embolectomy screen 111 in the second environment is also generally smaller than the diameter of the embolectomy screen 111 in the fourth environment, that is, the diameter of the embolectomy screen 111 in a free state is larger than the diameter of the embolectomy screen in a collapsed state or an extended state. Thus, the embolectomy screen 111 can be better attached to the vessel wall, further ensuring that small emboli do not escape again.

Furthermore, it is also necessary to supplement that when the thrombectomy stent is multiple, the push-pull tube 130 passes through the stents in turn, and the proximal end of each thrombectomy stent is connected with the outer surface of the push-pull tube 130. Also, a developing ring may be provided at a portion where the proximal end of each stent is connected to the push-pull tube 130.

the embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other.

the above description is only for the purpose of describing the preferred embodiments of the present invention, and is not intended to limit the scope of the present invention, and any variations and modifications made by those skilled in the art based on the above disclosure are within the scope of the appended claims.