Thrombectomy catheter

Abstract

Embodiments of the present disclosure provide a thrombus aspiration catheter. The thrombus aspiration catheter includes a first tube body, and a suction tube coaxial therewith is rotatably connected at one of its ports; a guiding cavity which is annular and has an opening facing the first tube body is provided on the suction tube; a plurality of flexible sheets which are distributed circumferentially around the tube orifice of the suction tube and are restricted to open unidirectionally into the tube orifice are provided at the tube orifice of the suction tube; a second tube body is sleeved in the first tube body in a manner that relative rotation is restricted but relative axial sliding is possible, and one end thereof is inserted into the guiding cavity. A rotation guiding mechanism includes a spiral guiding portion and a sliding portion slidably engaged with the guiding portion; the sliding portion is formed at one end of the second tube body inserted into the guiding cavity; wherein, the edges of the plurality of flexible sheets form a stirring portion for stirring and dispersing the contacted thrombus when in an open state and being driven to rotate by the relative sliding of the first tube body and the second tube body. The rotation guiding mechanism can drive the suction tube to rotate and move outwards.

Description

Technical Field

[0001] The present disclosure relates to the technical field of medical devices, and particularly to a thrombus aspiration catheter. Background Art

[0002] Intracranial vascular intervention surgery is one of the important means for treating cerebrovascular diseases. Among them, the stent retriever combined with aspiration catheter technology is widely used in the treatment of acute ischemic stroke. However, most of the existing aspiration catheters are only suitable for the stent to enter to pull the thrombus into the aspiration catheter. However, when the existing aspiration catheter aspirates the thrombus, the relatively large thrombus is easily stuck at the catheter orifice and cannot pass through the aspiration catheter smoothly to be aspirated outside the blood vessel. It is also easy to cause partial thrombus reflux in the catheter due to blockage of the catheter orifice, thereby increasing the risk of distal embolism. Summary of the Invention

[0003] In view of the above-mentioned disadvantages of the prior art, the purpose of the present disclosure is to provide a thrombus aspiration catheter to solve the problems in the related art.

[0004] The present disclosure provides a thrombus aspiration catheter in a first aspect, including:

[0005] A first tube body, at one end of which a suction tube coaxial with it is rotatably connected; a guiding cavity that is annular and has an opening facing the first tube body is provided on the suction tube; a plurality of flexible sheets are provided at the orifice of the suction tube and are distributed circumferentially along the orifice and are restricted to open unidirectionally into the orifice; wherein, the plurality of flexible sheets form corresponding openings of the orifice in response to the suction force inside the first tube body;

[0006] A second tube body, which is sleeved in the first tube body in a manner that is restricted from relative rotation but can slide axially relative to it, and one end is inserted into the guiding cavity;

[0007] A rotation guiding mechanism, including a spiral guiding portion and a sliding portion slidably engaged with the guiding portion; the guiding portion is spirally extended around the central axis of the suction tube and formed on the wall surface of the guiding cavity; the sliding portion is formed at one end of the second tube body inserted into the guiding cavity; wherein, the edges of the plurality of flexible sheets form a stirring portion for stirring the contacted thrombus when in the open state and being driven to rotate by the relative sliding of the first tube body and the second tube body.

[0008] In an embodiment of the first aspect, the stirring portion has an acute angle shape, and the angle range is 10 degrees - 45 degrees.

[0009] In an embodiment of the first aspect, the manner in which the first tube body and the second tube body generate relative axial movement is implemented as: the first tube body slides relative to the second tube body.

[0010] In an embodiment of the first aspect, it further includes a guiding unit; the guiding unit includes a guiding groove and a guiding block that are slidably combined; the guiding groove is formed on the outer wall surface of the second tube body and extends along the axis of the second tube body, and the guiding block is arranged on the inner wall surface of the first tube body.

[0011] In an embodiment of the first aspect, one of the wall surfaces of the first tube body and the suction tube that are in contact forms an annular groove, and the other forms an annular block that is slidably combined in the groove.

[0012] In an embodiment of the first aspect, the guiding portion is implemented as being recessed in the wall surface of the guiding cavity, and the sliding portion is protruded on the wall surface of the second tube body; and / or, the guiding portion is implemented as being protruded on the wall surface of the guiding cavity, and the sliding portion is recessed in the wall surface of the second tube body.

[0013] In an embodiment of the first aspect, when the flexible sheet is in an open state, the included angle between the flexible sheet and the inner wall of the suction tube is negatively correlated with the magnitude of the suction force inside the second tube body.

[0014] In an embodiment of the first aspect, the flexible sheet includes a fixing portion and a shielding portion; the fixing portion is connected to the inner wall of the suction tube.

[0015] In an embodiment of the first aspect, the inside of the second tube body is provided for an unopened stent assembly to pass through. The stent assembly is configured to be released after penetrating or passing through a thrombus to form a state capable of driving the thrombus. In a state where the plurality of flexible sheets open the tube orifice, the released stent assembly withdraws the thrombus from the tube orifice from the blood vessel.

[0016] In an embodiment of the first aspect, the plurality of flexible sheets are arranged on the inner wall of the suction tube at an interval from the tube orifice.

[0017] As described above, the embodiments of the present disclosure provide a thrombus aspiration catheter, which includes a first tube body, a second tube body, and a rotation guiding mechanism. One end of the first tube body is rotatably connected to a suction tube coaxial with it; a guiding cavity that is annular and has an opening facing the first tube body is provided on the suction tube; a plurality of flexible sheets are provided at the tube orifice of the suction tube and are distributed circumferentially along the tube orifice and are restricted to open unidirectionally into the tube orifice; wherein, the plurality of flexible sheets form corresponding openings of the tube orifice in response to the suction force inside the first tube body. The second tube body is restricted from relative rotation but is sleeved inside the first tube body and can slide axially relative to it, and one end is inserted into the guiding cavity. The rotation guiding mechanism includes a spiral guiding portion and a sliding portion slidably engaged with the guiding portion; the guiding portion is formed on the wall surface of the guiding cavity by spirally extending around the central axis of the suction tube; the sliding portion is formed at one end of the second tube body inserted into the guiding cavity; wherein, the edges of the plurality of flexible sheets form a stirring portion for stirring the contacted thrombus when in the open state and being driven to rotate by the relative sliding of the first tube body and the second tube body. The advantage of the above arrangement is that when the first tube body and the second tube body move axially relative to each other, the rotation guiding mechanism can drive the suction tube to rotate and move outwards, so that the flexible sheets stir the thrombus located at the tube orifice, nibble on relatively large thrombus and remove it from the blood vessel. Description of the Drawings

[0018] Figure 1 The figure shows a schematic diagram of the flexible sheet in the closed state in the embodiments of the present disclosure;

[0019] Figure 2 The figure shows another perspective schematic diagram of the flexible sheet in the closed state in the embodiments of the present disclosure;

[0020] Figure 3 The figure shows a schematic diagram of the flexible sheet in the open state and cooperating with the stent assembly in the embodiments of the present disclosure;

[0021] Figure 4 The figure shows another perspective schematic diagram of the flexible sheet in the open state in the embodiments of the present disclosure;

[0022] Figure 5 The figure shows the embodiments of the present disclosure Figure 1 An enlarged view of A in the figure;

[0023] Figure 6 The figure shows a schematic structural diagram of the thrombus aspiration catheter in another embodiment of the present disclosure;

[0024] Figure 7 The figure shows a schematic structural diagram of another perspective of the thrombus aspiration catheter in another embodiment of the present disclosure;

[0025] Figure 8 The figure shows a schematic structural diagram of the tube orifice of the thrombus aspiration catheter in another embodiment of the present disclosure being opened;

[0026] Figure 9 Shown therein is a schematic structural view of another perspective of the nozzle opening of the thrombus aspiration catheter in another embodiment of the present disclosure;

[0027] Figure 10 Shown therein is a schematic structural view of the cooperation between the thrombus aspiration catheter and the stent assembly in another embodiment of the present disclosure;

[0028] Figure 11 Shown therein is a schematic structural view of another state of the cooperation between the thrombus aspiration catheter and the stent assembly in another embodiment of the present disclosure. Detailed Embodiments

[0029] The following uses specific examples to illustrate the embodiments of the present disclosure. Those skilled in the art can easily understand other advantages and effects of the present disclosure from the information disclosed in the present disclosure. The present disclosure can also be implemented or applied through different specific embodiments. Various details in the present disclosure can also be modified or changed according to different viewpoints and applications without departing from the spirit of the present disclosure. It should be noted that, without conflict, the embodiments and features in the embodiments of the present disclosure can be combined with each other.

[0030] The following takes the drawings as a reference and details the embodiments of the present disclosure so that those skilled in the art to which the present disclosure pertains can easily implement it. The present disclosure can be embodied in many different forms and is not limited to the embodiments described herein.

[0031] In the description of the present disclosure, the reference terms "one embodiment", "some embodiments", "example", "specific example", or "some examples", etc., mean that the specific features, structures, materials, or characteristics represented in connection with the embodiment or example are included in at least one embodiment or example of the present disclosure. Moreover, the specific features, structures, materials, or characteristics represented can be combined in any one or a group of embodiments or examples in a suitable manner. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples represented in the present disclosure and the features of the different embodiments or examples.

[0032] In addition, the terms "first" and "second" are only used for the purpose of indication and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" can explicitly or implicitly include at least one of the features. In the description of the present disclosure, the meaning of "a group" is two or more unless otherwise specifically defined.

[0033] In order to clearly illustrate the present disclosure, devices irrelevant to the description are omitted, and the same or similar components throughout the specification are given the same reference numerals.

[0034] Throughout the specification, when a device is said to be "connected" to another device, this includes not only the case of "direct connection", but also the case of "indirect connection" where other elements are placed in between. In addition, when a device is said to "include" a certain component, unless there is a particularly contrary record, it does not exclude other components, but means that other components may also be included.

[0035] Although in some examples the terms first, second, etc. are used herein to denote various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, the first interface and the second interface, etc. are indicated. Furthermore, as used herein, the singular forms "a", "an" and "the" are also intended to include the plural forms unless the context indicates otherwise. It should be further understood that the terms "comprising", "including" indicate the presence of the stated features, steps, operations, elements, modules, items, kinds, and / or groups, but do not preclude the presence, occurrence or addition of one or a group of other features, steps, operations, elements, modules, items, kinds, and / or groups. The terms "or" and "and / or" used herein are interpreted as inclusive, or meaning any one or any combination. Thus, "A, B or C" or "A, B and / or C" means "any one of the following: A; B; C; A and B; A and C; B and C; A, B and C". An exception to this definition only occurs when the combination of elements, functions, steps or operations are mutually exclusive in some way.

[0036] The technical terms used herein are only for referring to specific embodiments and are not intended to limit the present disclosure. The singular forms used herein also include the plural forms as long as the statement does not clearly indicate the contrary meaning. The meaning of "including" used in the specification is to embody specific characteristics, regions, integers, steps, operations, elements and / or components, and does not exclude the existence or addition of other characteristics, regions, integers, steps, operations, elements and / or components.

[0037] Although not defined differently, including the technical terms and scientific terms used herein, all terms have the same meaning as generally understood by those skilled in the art to which the present disclosure pertains. Terms defined in commonly used dictionaries are additionally interpreted to have a meaning consistent with the relevant technical literature and the currently presented information, and should not be over-interpreted as ideal or very formulaic meanings as long as they are not defined.

[0038] Intracranial vascular interventional surgery is one of the important means for treating cerebrovascular diseases. Among them, the stent thrombectomy combined with aspiration catheter technology is widely used in the treatment of acute ischemic stroke. However, most of the existing aspiration catheters are only suitable for the stent to enter to pull the thrombus into the aspiration catheter. But when the existing aspiration catheter aspirates the thrombus, the relatively large thrombus is easily stuck at the catheter orifice and cannot pass through the aspiration catheter smoothly to be aspirated outside the blood vessel. It is also easy to cause partial thrombus reflux in the catheter due to blocking the catheter orifice, thereby increasing the risk of distal embolism.

[0039] Based on the above problems, when the first tube body and the second tube body axially move relative to each other in the embodiments of the present disclosure, the rotation guiding mechanism can drive the suction tube to rotate and move outward, so as to make the flexible sheet disperse the thrombus located at the catheter orifice. Devour the relatively large thrombus and remove it from the blood vessel through the catheter.

[0040] Figure 1 Shown is a schematic diagram of the flexible sheet in the closed state in the embodiments of the present disclosure. Figure 2 Shown is another perspective schematic diagram of the flexible sheet in the closed state in the embodiments of the present disclosure. Figure 3 Shown is a schematic diagram of the flexible sheet in the open state and cooperating with the stent assembly in the embodiments of the present disclosure. Figure 4 Shown is another perspective schematic diagram of the flexible sheet in the open state in the embodiments of the present disclosure. Figure 5 Shown is the embodiments of the present disclosure Figure 1 An enlarged view of A in. In Figure 1 、 2 、3, 4 and Figure 5 In the examples, the thrombus aspiration catheter includes a first tube body 40, a second tube body 50 and a rotation guiding mechanism 60. One end of the first tube body 40 is rotatably connected with a suction tube 70 coaxial with it; an annular guiding cavity 701 with an opening facing the first tube body 40 is provided on the suction tube 70; a plurality of flexible sheets 71 distributed circumferentially along the catheter orifice 702 of the suction tube 70 and restricted to open unidirectionally into the catheter orifice 702 are provided at the catheter orifice 702 of the suction tube 70; wherein, the plurality of flexible sheets 71 form a corresponding opening degree of the catheter orifice 702 in response to the suction force inside the first tube body 40.

[0041] The second tube body 50 is restricted from rotating but can be axially slidably sleeved inside the first tube body 40, and one end is inserted into the guiding cavity 701.

[0042] The rotation guiding mechanism 60 includes a spiral guiding portion 61 and a sliding portion 62 slidably engaged with the guiding portion 61; the guiding portion 61 is formed on the wall surface of the guiding cavity 701 spirally extending around the central axis of the suction pipe 70; the sliding portion 62 is formed at one end of the second pipe body 50 inserted into the guiding cavity 701; wherein, the edges of the plurality of flexible sheets 71 form stirring portions 711 for dispersing the thrombus contacted when in the open state and driven to rotate by the relative sliding of the first pipe body 40 and the second pipe body 50.

[0043] The advantage of the above arrangement is that when the first pipe body 40 and the second pipe body 50 move axially relative to each other, the rotation guiding mechanism 60 can drive the suction pipe 70 to rotate and move outwards, so that the flexible sheet 71 disperses the thrombus located at the pipe orifice. The larger thrombus is nibbled and removed from the blood vessel.

[0044] In Figure 5 In an example, the guiding portion 61 is implemented as being recessed in the wall surface of the guiding cavity 701, and the sliding portion 62 is protruded from the wall surface of the second pipe body 50. Exemplarily, the sliding portion 62 is engaged with the guiding portion 61 near the end or the middle of the first pipe body 40. In another embodiment, the guiding portion 61 is implemented as being protruded from the wall surface of the guiding cavity 701, and the sliding portion 62 is recessed in the wall surface of the second pipe body 50.

[0045] Exemplarily, the flexible sheet 71 includes a fixing portion 712 and a shielding portion 713; the fixing portion 712 is connected to the inner wall of the pipe. The stirring portion 711 has an acute angle shape, and the angle range is 10 degrees - 45 degrees. It can be understood that the acute angle shape can improve the sharpness of the stirring portion 711 to effectively cut the contacted thrombus when in the open state. Further exemplarily, the stirring portion 711 is formed at the edge of the shielding portion 713 of the flexible sheet 71.

[0046] Exemplarily, the included angle between the flexible sheet 71 and the inner wall of the suction pipe 70 when in the open state is negatively correlated with the magnitude of the suction force inside the second pipe body 50.

[0047] Exemplarily, the manner in which the first tube body 40 and the second tube body 50 generate relative axial movement is implemented as follows: the first tube body 40 slides relative to the second tube body 50. Those skilled in the art can understand that after the second tube body 50 is connected to the negative pressure device, when it is necessary to use the flexible sheet 71 to disperse thrombus, the operator increases the negative pressure inside the second tube body 50 to increase the opening degree of the flexible sheet 71, so that a part of the larger thrombus enters the nozzle 702 of the suction tube 70; then the negative pressure of the second tube body 50 is reduced, so that the flexible sheet 71 can contact the thrombus entering the nozzle 702 of the suction tube 70. At this time, the operator keeps the second tube body 50 stationary and pulls the first tube body 40 outwards. The first tube body 40 drives the suction tube 70 to move outwards. While the suction tube 70 is moving outwards, the suction tube 70 rotates under the cooperation of the guiding part 61 and the sliding part 62, so that while the suction tube 70 moves outwards and pulls the thrombus by the stirring part 711 of the flexible sheet 71, it also rotates to cut the thrombus, so as to disperse and shed part of the thrombus from the larger thrombus. Then push the first tube body 40 inwards to reset the suction tube 70 to its original position. When the thrombus enters the nozzle 702 of the suction tube 70 again, repeat the above process.

[0048] In Figure 1 and Figure 5 an example, the thrombus aspiration catheter further includes a guiding unit 80; the guiding unit 80 includes a guiding groove 81 and a guiding block 82 that are slidably combined; the guiding groove 81 is formed on the outer wall surface of the second tube body 50 and extends along the axis of the second tube body 50, and the guiding block 82 is arranged on the inner wall surface of the first tube body 40. It can be understood that the guiding unit 80 can make the first tube body 40 and the second tube body 50 only generate relative axial movement and cannot rotate relative to each other. Thus, it is avoided that the rotation guiding mechanism 60 fails due to the relative rotation of the first tube body 40 and the second tube body 50.

[0049] In Figure 5 an example, one of the walls where the first tube body 40 and the suction tube 70 are in contact forms an annular groove 401, and the other forms an annular block 72 that is slidably combined in the groove 401. In this embodiment, the groove 401 is formed on the wall surface of the first tube body 40, and the annular block 72 is arranged on the wall surface of the suction tube 70. It can be understood that the combination of the annular block 72 and the groove 401 not only realizes the connection between the first tube body 40 and the suction tube 70, but also can realize the rotation of the first tube body 40 and the suction tube 70. Exemplarily, the cross-sectional shapes of the groove 401 and the annular block 72 are implemented as three-quarter circular. In another embodiment, the cross-sectional shapes of the groove 401 and the annular block 72 are implemented as an inverted T shape.

[0050] In Figure 3 the example, the inside of the second tube body 50 is provided for the unopened stent assembly 30 to pass through. The stent assembly 30 is provided to be released after penetrating or passing through a thrombus to form a state capable of driving the thrombus, so that in the state where the plurality of flexible sheets 71 open the tube orifice 702, the released stent assembly 30 withdraws the thrombus from the tube orifice 702 out of the blood vessel. Exemplarily, the stent assembly 30 includes a microcatheter 31 and a stent 32 disposed within the microcatheter 31.

[0051] Another embodiment of the present disclosure provides an operation method, which is applied to the thrombus aspiration catheter. The method includes the following steps:

[0052] S101: Set the tube orifices of the tube bodies of the plurality of flexible sheets to approach a thrombus under the guidance of a guide wire;

[0053] S102: Connect the other tube orifice of the second tube body to an external negative pressure device. The plurality of flexible sheets no longer cover the tube orifice, and fragmented thrombi enter the inside of the tube body through the tube orifice under negative pressure suction;

[0054] S103: When the tube orifice is blocked by a thrombus, the plurality of flexible sheets resume covering the tube orifice due to the absence of continuous negative pressure inside the second tube body, so as to prevent the thrombus that has entered the inside of the second tube body from causing distal embolism due to flowing back into the blood vessel;

[0055] S104: Disconnect the connection between the second tube body and the external negative pressure device; the stent assembly passes through the inside of the second tube body and opens the tube orifice after the head end abuts against the plurality of flexible sheets, and then penetrates the thrombus;

[0056] S105: Retain the stent and withdraw the microcatheter into the inside of the second tube body. The stent separated from the microcatheter unfolds and immerses into the thrombus;

[0057] S106: After the stent is fully engaged with the thrombus, the second tube body is reconnected to the external negative pressure device, and the negative pressure intensity is appropriately increased to improve the degree of opening of the tube orifice by the plurality of flexible sheets;

[0058] S107: Slowly synchronously pull the microcatheter and the stent, and the stent drives the thrombus to slowly pass through the opened pipe orifice; during this process, when a part of the thrombus enters the inside of the suction pipe and reaches the position where it contacts the flexible sheet, keep the stent stationary and drive the first tube body to slide relative to the second tube body, so that when the suction pipe moves outward, it rotates and drives the plurality of flexible sheets to disperse a part of the thrombus located inside the pipe orifice; at the same time, the suction pipe is driven outward to a state where the inner cavity of the suction pipe communicates with the blood vessel, so that the dispersed thrombus can be sucked to the outside of the body by the second tube body; when it is necessary to disperse a part of the thrombus again to reduce the volume of the thrombus, push the first tube body inward until the suction pipe returns to its original position, and then repeat this step;

[0059] S108: Pull the stent until the thrombus that has been dispersed can be completely incorporated into the inside of the suction pipe, so that after the thrombus passes over the plurality of flexible sheets, the plurality of flexible sheets cover the pipe orifice again to prevent the thrombus inside the suction pipe from flowing back;

[0060] S109: When continuous stent thrombectomy is required, repeat S104 - S108; if not, remove the first tube body and the second tube body, and the suction is completed.

[0061] Figure 6 Shown is a schematic structural diagram of a thrombus aspiration catheter in another embodiment of the present disclosure. Figure 7 Shown is a schematic structural diagram of another perspective of the thrombus aspiration catheter in another embodiment of the present disclosure. Figure 8 Shown is a schematic structural diagram of the opened pipe orifice of the thrombus aspiration catheter in another embodiment of the present disclosure. Figure 9 Shown is a schematic structural diagram of another perspective of the opened pipe orifice of the thrombus aspiration catheter in another embodiment of the present disclosure.

[0062] In Figure 6 , 7 , 8 and Figure 9 In the examples, the thrombus aspiration catheter includes a tube body 10, and at one pipe orifice 702A of the tube body 10, a plurality of flexible sheets 71A are arranged along the circumferential direction of the pipe orifice 702A and are restricted to open unidirectionally into the pipe orifice 702A; wherein, the plurality of flexible sheets 71A close the pipe orifice 702A when there is no suction inside the tube body 10; and open the pipe orifice 702A when there is suction inside the tube body 10.

[0063] The advantage of the above settings is that after the other pipe orifice 702A of the pipe body 10 is connected to a negative pressure device, the inside of the pipe body 10 has suction force, and when there is suction force inside the pipe body 10, the plurality of flexible sheets 71A open the pipe orifice 702A. At this time, part of the thrombus can be sucked into the inside of the pipe body 10 through the opened pipe orifice 702A. When the pipe orifice 702A is blocked by a thrombus, the plurality of flexible sheets 71A re-cover the pipe orifice 702A due to the continuous suction force inside the pipe body 10, preventing the thrombus that has entered the inside of the pipe body 10 from flowing back into the blood vessel. The time and effort consumed in dealing with thrombus backflow are reduced, and the surgical efficiency is improved.

[0064] Figure 10 Shown is a schematic structural diagram of the cooperation between a thrombus aspiration catheter and a stent assembly in another embodiment of the present disclosure. Figure 11 Shown is a schematic structural diagram of another state of the cooperation between a thrombus aspiration catheter and a stent assembly in another embodiment of the present disclosure. In Figure 10 and Figure 11 In the example, the inside of the pipe body 10 is provided for the stent assembly 30 that is not opened to pass through. The stent assembly 30 is configured to be released after penetrating or passing through a thrombus to form a state capable of driving the thrombus, so that in the state where the plurality of flexible sheets 71A open the pipe orifice 702A, the thrombus is drawn out of the blood vessel from the pipe orifice 702A by the applied acting portion. Exemplarily, the stent assembly 30 includes a microcatheter 31 and a stent 32 disposed within the microcatheter 31.

[0065] In Figure 7 In the example, the flexible sheet 71A includes a fixing portion 712A and a shielding portion 713A. The fixing portion 712A is connected to the inner wall of the pipe body 10. The shielding portions 713A of the plurality of flexible sheets 71A jointly cover the pipe orifice 702A.

[0066] Exemplarily, the flexible sheet 71A is implemented as four; the four flexible sheets 71A are circumferentially distributed along the inner wall of the pipe orifice 702A. In another embodiment, the flexible sheet 71A is implemented as three or five, which is not limited thereto, but the plurality of flexible sheets 71A can completely cover the pipe orifice 702A in the initial state.

[0067] Further exemplarily, the shielding portions 713A of the plurality of flexible sheets 71A partially overlap. It can be understood that the partially overlapping plurality of flexible sheets 71A can further improve the coverage of the pipe orifice 702A. The effect of the plurality of flexible sheets 71A blocking the backflow of thrombus through the pipe orifice 702A is improved.

[0068] In Figure 8In the example, the opening degree of the pipe orifice 702A is positively correlated with the magnitude of the suction force inside the pipe body 10. Those skilled in the art can understand that as the suction force inside the pipe body 10 increases, the amplitude of the shielding portions 713A of the plurality of flexible sheets 71A swinging towards the inside of the pipe increases, so as to increase the gap between the plurality of flexible sheets 71A, thereby increasing the opening degree of the pipe orifice 702A and facilitating the passage of the remaining thrombus subsequently.

[0069] In Figure 6 and Figure 8 In the example, the plurality of flexible sheets 71A are disposed on the inner wall of the pipe body 10 at a distance from the pipe orifice 702A. The advantage of such a setting is that when the pipe orifice 702A is blocked by a thrombus, the thrombus can be partially caught in the space between the plurality of flexible sheets 71A and the pipe orifice 702A, so as to further improve the stability between the thrombus and the pipe body 10.

[0070] Exemplarily, the flexible sheet 71A is made of medical silicone or the same material as a biological valve. Exemplarily, the outer wall of the pipe body 10 is coated with a hydrophilic coating; the hydrophilic coating is implemented as polyvinylpyrrolidone. Further exemplarily, the inner diameter of the pipe body 10 is 1.11 mm to 1.73 mm.

[0071] Another embodiment of the present disclosure provides an operation method, which is applied to the thrombus aspiration catheter. The method includes the following steps:

[0072] S201: Set the pipe orifice of the pipe body with the plurality of flexible sheets to approach the thrombus under the guidance of a guide wire;

[0073] S202: Connect the other pipe orifice of the pipe body to an external negative pressure device, the plurality of flexible sheets no longer cover the pipe orifice, and the fragmented thrombus enters the inside of the pipe body through the pipe orifice under negative pressure suction;

[0074] S203: When the pipe orifice is blocked by a thrombus, the plurality of flexible sheets recover to cover the pipe orifice due to the absence of continuous negative pressure inside the pipe body, so as to prevent the thrombus that has entered the inside of the pipe body from causing distal embolism due to flowing back into the blood vessel;

[0075] S204: Disconnect the connection between the pipe body and the external negative pressure device; the stent assembly passes through the inside of the pipe body and opens the pipe orifice after abutting against the plurality of flexible sheets at the head end, and then penetrates through the thrombus;

[0076] S205: Retain the stent and withdraw the microcatheter into the inside of the pipe body, and the stent separated from the microcatheter unfolds and immerses in the thrombus;

[0077] S206: After the stent is fully fitted to the thrombus, the tube body is reconnected to the external negative pressure device, and the negative pressure intensity is appropriately increased to enhance the degree to which the plurality of flexible sheets open the tube orifice;

[0078] S207: Slowly and synchronously pull the microcatheter and the stent, and the stent drives the thrombus to slowly pass through the opened tube orifice;

[0079] S208: When the thrombus completely enters the interior of the tube body and passes over the plurality of flexible sheets, the plurality of flexible sheets cover the tube orifice again to prevent the thrombus inside the tube body from flowing back;

[0080] S209: When continuous stent thrombectomy is required, repeat S204 - S208; if not, remove the tube body and the aspiration ends.

[0081] Exemplarily, another operation method in another embodiment of the present disclosure is implemented to include the following steps:

[0082] S301: The tube body, under the guidance of a guide wire, makes the tube orifice where the plurality of flexible sheets are provided close to the thrombus;

[0083] S302: The other tube orifice of the tube body is connected to the external negative pressure device. The shielding portions of the plurality of flexible sheets generate gaps due to deflection towards the other tube orifice under the action of negative pressure, thus opening the tube orifice; Fine thrombus enters the interior of the tube body through the gaps at the tube orifice under negative pressure suction;

[0084] S303: When the tube orifice is blocked by the thrombus, the shielding portions of the plurality of flexible sheets re - swing to cover the tube orifice again because negative pressure cannot be continuously formed inside the tube body, thereby preventing the thrombus that has entered the interior of the tube body from causing distal embolism due to flowing back into the blood vessel;

[0085] S304: Disconnect the connection between the tube body and the external negative pressure device; After the microcatheter and the stent penetrate into the interior of the tube body and the head end abuts against the plurality of flexible sheets, due to the friction between the outer wall of the external microcatheter and the shielding portion of the flexible sheet, the shielding portion of the flexible sheet is driven to slightly swing towards the thrombus direction until the microcatheter and the stent penetrate through the blocked thrombus;

[0086] S305: Keep the position of the stent in the blood vessel stationary and slowly retract the microcatheter. Due to the friction between the outer wall of the microcatheter and the shielding portion of the flexible sheet, the shielding portion of the flexible sheet is driven to slightly swing towards the direction of the other tube orifice. After the microcatheter disengages from the contact with the flexible sheet, the shielding portion of the flexible sheet abuts against the guide wire connecting the stent;

[0087] S306: The stent released from the restraint of the microcatheter unfolds and fits to the thrombus;

[0088] S307: Perform angiography to observe whether the stent is in the appropriate position. If the position is appropriate, stay for five minutes to allow the stent to tightly fit with the thrombus. If the position is inappropriate, adjust the position of the stent.

[0089] S308: Reconnect the tube body to the external negative pressure device and appropriately increase the negative pressure intensity, so that the shielding parts of the plurality of flexible sheets deflect towards the other pipe orifice under the action of negative pressure, thereby increasing the degree to which the plurality of flexible sheets open the pipe orifice.

[0090] S309: Slowly and synchronously pull the microcatheter and the stent. After the microcatheter enters the tube body, the stent drives the thrombus to slowly pass through the pipe orifice with an increased opening degree.

[0091] S310: When the stent drives the thrombus to completely enter the interior of the tube body and pass over the plurality of flexible sheets, the plurality of flexible sheets will swing back to the state of covering the pipe orifice because the interior of the tube body behind the stent cannot continuously form negative pressure, thereby preventing the thrombus that has entered the interior of the tube body from causing distal embolism due to flowing back into the blood vessel.

[0092] S311: When continuous stent thrombectomy is required, repeat S304 - S310. If not, remove the tube body and the aspiration is completed.

[0093] In summary, the embodiments of the present disclosure provide a thrombus aspiration catheter, which includes a first tube body, a second tube body, and a rotation guiding mechanism. One end of the first tube body is rotatably connected to a suction tube coaxial with it; the suction tube is provided with an annular guiding cavity with an opening facing the first tube body; the orifice of the suction tube is provided with a plurality of flexible sheets distributed circumferentially along the orifice and restricted to open unidirectionally into the orifice; wherein, the plurality of flexible sheets form corresponding opening degrees of the orifice in response to the suction force inside the first tube body. The second tube body is restricted from relative rotation but can be sleeved in the first tube body and axially slid relative to it, and one end is inserted into the guiding cavity. The rotation guiding mechanism includes a spiral guiding part and a sliding part slidably engaged with the guiding part; the guiding part is spirally extended around the central axis of the suction tube on the wall surface of the guiding cavity; the sliding part is formed at one end of the second tube body inserted into the guiding cavity; wherein, the edges of the plurality of flexible sheets form stirring parts, which are used to disperse the contacted thrombus when in the open state and driven to rotate by the relative sliding of the first tube body and the second tube body. The advantage of the above setting is that when the first tube body and the second tube body move axially relative to each other, the rotation guiding mechanism can drive the suction tube to rotate and move outwards, so that the flexible sheets disperse the thrombus located at the orifice of the tube. Devour larger thrombi and remove them from the blood vessel through the catheter.

[0094] The above embodiments are only illustrative of the principles and effects of the present disclosure, and are not intended to limit the present disclosure. Any person familiar with this technology can modify or change the above embodiments without departing from the spirit and scope of the present disclosure. Therefore, all equivalent modifications or changes made by those with ordinary knowledge in the technical field without departing from the spirit and technical ideas disclosed by the present disclosure should still be covered by the protection scope of the present disclosure.

Claims

1. A thrombus aspiration catheter, characterized in that: include: A first tube body, wherein a suction tube coaxially connected to one end thereof is rotatably connected thereto; the suction tube is provided with a guide cavity in an annular shape and opening toward the first tube body; a plurality of flexible sheets distributed along the circumference of the tube mouth and restricted to be able to open unidirectionally into the tube mouth are provided at the tube mouth of the suction tube; wherein the plurality of flexible sheets form a corresponding opening of the tube mouth in response to the suction force inside the first tube body; A second tube body is restricted from relative rotation but can be relatively slidably fitted into the first tube body along the axial direction, and one end of the second tube body is inserted into the guide cavity; The rotary guide mechanism comprises a spiral guide portion and a sliding portion slidably coupled to the guide portion; the guide portion is formed on the wall surface of the guide cavity and spirally extends around the central axis of the suction tube; the sliding portion is formed at one end of the second tube body inserted into the guide cavity; wherein the edges of the plurality of flexible sheets form a stirring portion, which is used to stir up the contacted thrombus when the first tube body and the second tube body are in an open state and driven to rotate by relative sliding between the first tube body and the second tube body; After the thrombus passes over the multiple flexible sheets, the multiple flexible sheets cover the tube opening again.

2. The thrombus aspiration catheter according to claim 1, characterized in that: The stirring portion is in an acute angle shape, and the angle range is 10 degrees to 45 degrees.

3. The thrombus aspiration catheter according to claim 1, characterized in that: The manner in which the first tube body and the second tube body generate axial relative movement is implemented as follows: the first tube body slides relative to the second tube body.

4. The thrombus aspiration catheter according to claim 1, characterized in that: It also includes a guide unit; the guide unit includes a guide groove and a guide block that are slidably combined; the guide groove is formed on the inner wall of the second tube body and extends along the axis of the second tube body, and the guide block is arranged on the inner wall of the first tube body.

5. The thrombus aspiration catheter according to claim 1, characterized in that: One of the walls where the first tube body and the suction tube are in contact forms an annular groove, and the other forms an annular block slidably engaged in the groove.

6. The thrombus aspiration catheter according to claim 1, characterized in that: The guide portion is implemented as being recessed on the guide cavity wall, and the sliding portion is convexly disposed on the second tube body wall; and / or, the guide portion is implemented as being convexly disposed on the guide cavity wall, and the sliding portion is recessed on the second tube body wall.

7. The thrombus aspiration catheter according to claim 1, characterized in that: The angle between the flexible sheet and the inner wall of the suction tube when the flexible sheet is in the open state is negatively correlated with the magnitude of the suction force inside the second tube body.

8. The thrombus aspiration catheter according to claim 1, characterized in that: The flexible sheet includes a fixing portion and a shielding portion; the fixing portion is connected to the inner wall of the suction pipe.

9. The thrombus aspiration catheter according to claim 1, characterized in that: An unopened stent assembly is inserted into the interior of the second tube body, and the stent assembly is released after penetrating or passing through a thrombus to form a state capable of driving the thrombus, so that when the multiple flexible sheets open the tube opening, the released stent assembly can pull the thrombus out of the blood vessel from the tube opening.

10. The thrombus aspiration catheter according to claim 1, characterized in that: A plurality of the flexible sheets are arranged on the inner wall of the suction pipe with a spacing between them and the pipe opening.

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