Thrombus capturing device and method

Abstract

The present invention provides a thrombus capture device and method. Specifically, the present invention provides a device on one hand, which includes a slender body, which has a proximal end connected to a delivery system and a plurality of capture units forming a cavity surface. The slender body is axially rotated while radially expanding. The present invention also provides another device, which includes two slender bodies, one of which is placed inside the other slender body. When the device is radially expanded, the two slender bodies are axially rotated independently of each other.

Description

[0001] This application is a divisional application of the invention patent with application date of August 10, 2018, application number 201810909251.X, and invention name “Thrombus capture device and method thereof”. Technical Field

[0002] The present invention relates to the field of medical devices, and more specifically to a minimally invasive catheter and a method for using the minimally invasive catheter to deliver a thrombus capture device in a vascular system, in particular a thrombus capture device for a cerebral vascular system. Background Art

[0003] Mechanical thrombectomy devices are used to salvage thrombi from ischemic but not yet completely blocked blood vessels in the brain, coronary arteries, peripheral vessels of the legs, and / or veins by restoring reperfusion to the originally blocked artery. Different types of mechanical thrombectomy devices achieve recanalization through slightly different mechanical mechanisms.

[0004] There are three types of catheter-based thrombectomy devices on the market. Aspiration catheters vacuum clots out of blood vessels, thrombolytic catheters inject targeted thrombus-directed drugs into clots for treatment, and mechanical thrombectomy devices capture clots and withdraw them into the catheter. Thrombectomy devices on the market can combine one or more of these thrombectomy mechanisms. Each of these thrombectomy mechanisms has its advantages and disadvantages.

[0005] Aspiration catheters remove occluding clots that cause acute ischemic stroke by vacuum aspiration. Any microcatheter can be used to manually aspirate the target clot, as long as the outer diameter of the microcatheter can pass through the intracranial artery. Aspiration catheters are usually used to remove small, fresh, soft clots in a rapid, single-shot restoration of blood flow. However, larger, organized clots can embolize the small bore of manual aspiration catheters, and manual aspiration is more likely to retain clots than mechanical methods. In addition, large-bore aspiration catheters are often difficult to pass through the lesion.

[0006] Directed thrombolytic catheters (CDT) deliver thrombolytic drugs through a catheter to dissolve clots and restore blood flow. Although directed thrombolytic therapy is superior to standard anticoagulation therapy, it is often not effective enough to treat severe coronary artery blockages in acute myocardial infarction or to restore blood flow in peripheral vessels. In the case of peripheral vessels, directed thrombolytic therapy alone may require a longer stay in the intensive care unit and frequent angiography to check the progress of thrombolysis. Removing large clots in neurovascular vessels often requires a large dose of thrombolytic drugs to completely dissolve the clot, and such a high dose of thrombolytic drugs increases the risk of bleeding.

[0007] Mechanical thrombectomy combined with systemic thrombolysis is the current standard of care for acute ischemic stroke. There are two types of mechanical thrombectomy devices: coil retrievers and stent retrievers. Coil retrievers consist of nickel-titanium shape memory wire and are threaded through a microcatheter into the target clot. When the coil retriever is pushed out of the delivery catheter, it immediately returns to its coiled shape. The neurointerventionist threads the loop of the coil through the clot and then pulls the coil and clot back into the catheter like a cork from a wine bottle. Stent retrievers are self-expanding stents that are placed into the clot blocking the vessel, the clot interacts with it and becomes embedded in the stent, and then the stent and clot are withdrawn back into the catheter.

[0008] The ability of stent retrievers to restore blood flow in a single operation allows them to remove more thrombi than manual aspiration and restore blood flow in a shorter time than thrombolytic therapy alone. Although stent retrievers have significant advantages in clinical outcomes for patients with acute ischemic stroke, their treatment is not without complications. Recent studies have found that stent retrievers can cause damage to the middle layer of arterial vessels. Another common disadvantage is that stent withdrawal inevitably produces thrombus fragments, which may cause distal embolism and occlusion of previously uninvolved areas. Therefore, there is still room for improvement. Summary of the invention

[0009] The object of the present invention is to provide a thrombus capture device and method for treating vascular embolism. The thrombus capture device of the present invention can better capture thrombi while reducing or even avoiding trauma to blood vessels. The thrombus capture efficiency is improved by rotating the device when it is released, the success rate of the operation is improved, and the possibility of generating thrombus fragments during thrombus capture is reduced.

[0010] In the first aspect of the present invention, a thrombus capture device is provided. Specifically, the thrombus capture device has a non-woven mesh tube structure, the mesh tube structure includes a slender body, the slender body includes a distal end, a proximal end, an axial cavity and a cavity surface; the cavity surface is provided with a plurality of capture units; each capture unit has a distal end and a proximal end; at least one of the capture units has a unit axis running through its distal end and proximal end, and the angle θ of the acute angle portion formed by the unit axis and the longitudinal axis of the slender body ranges from 10 to 80 degrees; the device has a radially collapsed profile during delivery and a radially expanded profile during release.

[0011] In another preferred embodiment, θ is preferably 15-75 degrees, and more preferably 20-70 degrees.

[0012] In another preferred embodiment, each of the capture units includes two wave rods.

[0013] In another preferred embodiment, at least one of the capture units comprises two wave bars with a wavy profile, and the two wave bars are centrally symmetrical around the unit axis of the capture unit.

[0014] In another preferred embodiment, at least one of the capture units has a different wave rod profile from at least one other of the capture units.

[0015] In another preferred embodiment, when the capturing unit radially expands, the cavity surface axially rotates toward the distal end of the capturing unit.

[0016] It should be noted that the release distance refers to the relative movement distance along the axial direction of the slender body when the thrombus capture device is released (Note: within this relative movement distance, only one-way rotation occurs), and the rotation angle refers to the deflection angle of any radial section of the slender body from the initial position to the final position when the above-mentioned relative movement distance occurs.

[0017] In another preferred embodiment, the unit axes of all the capturing units are parallel to each other.

[0018] In another preferred embodiment, the device is left-handed along the axis, and the rotation angle range per unit release distance is 0-90 degrees / mm.

[0019] In another preferred embodiment, the device is right-handed along the axis, and the rotation angle range per unit release distance is 0-90 degrees / mm.

[0020] In another preferred embodiment, each of the capture units has a height and a length, and at least one of the capture units has a different height-to-length ratio from at least one other of the capture units.

[0021] In another preferred embodiment, when the device expands radially, it first rotates axially in one direction and then rotates axially in the opposite direction. When the device rotates counterclockwise along the axis, the rotation angle range per unit release distance is 0-90 degrees / mm; when the device rotates clockwise along the axis, the rotation angle range per unit release distance is 0-90 degrees / mm.

[0022] In another preferred embodiment, when the device expands radially, it first rotates axially at one rotation speed and then rotates axially at another rotation speed. When the device rotates counterclockwise along the axis, the rotation angle range per unit release distance is 0-90 degrees / mm; when the device rotates clockwise along the axis, the rotation angle range per unit release distance is 0-90 degrees / mm.

[0023] In another preferred embodiment, the device is first axially rotated at one torsional strength and then axially rotated at another torsional strength when radially expanding.

[0024] In the second aspect of the present invention, another thrombus capture device is provided. Specifically, the device includes a plurality of slender bodies, and the plurality of slender bodies include at least an outer slender body and an inner slender body, the outer slender body includes an outer axial cavity and an outer cavity surface; the inner slender body includes an inner axial cavity and an inner cavity surface; the inner slender body is located in the outer axial cavity, and the proximal end of the inner slender body is interconnected with the proximal end of the outer slender body; the device has a radially collapsed profile during delivery and a radially expanded profile during release.

[0025] In another preferred embodiment, the cavity surfaces of the plurality of slender bodies each include a plurality of capture units.

[0026] In another preferred embodiment, a unit axis of at least one of the capturing units of the internal elongated body forms an acute angle with a longitudinal axis of the internal elongated body.

[0027] In another preferred example, a unit axis of at least one of the capturing units of the external elongated body forms an acute angle with a longitudinal axis of the external elongated body.

[0028] In another preferred embodiment, when the device is radially expanded, at least one of the inner elongated body and the outer elongated body is axially rotated.

[0029] In another preferred embodiment, when the device is radially expanded, at least one of the inner elongated body and the outer elongated body is first axially rotated in one direction and then axially rotated in another direction.

[0030] In another preferred embodiment, the inner elongated body rotates axially in one direction, and the outer elongated body rotates axially in another direction.

[0031] In another preferred embodiment, the inner elongated body rotates at one rotational speed, and the outer elongated body rotates at another rotational speed.

[0032] In another preferred embodiment, when the device is radially expanded, at least one of the inner elongated body and the outer elongated body is first axially rotated at one rotation speed and then axially rotated at another rotation speed.

[0033] In another preferred example, the inner elongated body rotates with one torsional strength, and the outer elongated body rotates with another torsional strength.

[0034] In another preferred example, the distal end of the inner elongated body is located at the distal end of the outer elongated body.

[0035] It should be understood that within the scope of the present invention, the above-mentioned technical features of the present invention and the technical features specifically described below (such as embodiments) can be combined with each other to form a new or preferred technical solution. Due to space limitations, they will not be described one by one here. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0037] Figure 1 is a perspective view of a typical installation.

[0038] Figure 2A-2B is a perspective view of various typical connection mechanisms between the proximal end of the device and the distal end of the delivery system.

[0039] Figure 3 yes Figure 1 A perspective view of the structural design of the capture unit of the slender body of a typical device.

[0040] Figure 4A-4B It is a perspective view of the arrangement of capture units of various typical devices in the prior art and the connection of struts to the proximal end of the device.

[0041] Figure 5A-5B It is a perspective view of various typical capture unit structures of the present invention.

[0042] Figure 6 It is a perspective view of the arrangement of capture units of a typical device of the present invention.

[0043] Figure 7 It is a perspective view of the structural design of the capture unit of the present invention.

[0044] Figure 8 It is a perspective view of the structural design of the capture unit of the present invention.

[0045] Fig. 9 is a perspective view of a typical capture unit arrangement of a typical device of the present invention.

[0046] Fig.10 is a perspective view of a typical capture unit arrangement of a typical device of the present invention.

[0047] Fig.11 It is a perspective view of a typical capture unit arrangement on the outside and a typical capture unit arrangement on the inside of a typical device of the present invention.

[0048] Figures 12A-12B It is a perspective view of a typical internal capture unit arrangement of the present invention.

[0049] Figures 13A-13B It is a perspective view of a typical internal capture unit arrangement of the present invention. DETAILED DESCRIPTION

[0050] The present invention provides a thrombus capture device and method for treating vascular embolism. Compared with the prior art, the thrombus capture device of the present invention includes a single-layer thrombus capture device and a double-layer thrombus capture device. The thrombus capture device of the present invention can be axially rotated while radially expanding, thereby having a better effect of capturing thrombi, reducing or even avoiding trauma to blood vessels, improving the success rate of the operation, and reducing the possibility of generating thrombus fragments during thrombus capture. The present invention is completed on this basis.

[0051] the term

[0052] The present invention provides a catheter-based embolus removal system. In certain embodiments, the embolus removal system of the present invention is used to remove thrombi in body vessels. In certain embodiments, the vessels refer to veins and / or arteries. In certain embodiments, the system is used to treat veins such as deep vein thrombosis (DVT) and arteries such as pulmonary embolism (PE), ST-segment elevation myocardial infarction (STEMI) and ischemic stroke. In certain embodiments, the system can also quickly remove artificial blood vessels that are prone to thrombosis, such as arteriovenous fistulas (AVGs). According to certain embodiments, after the catheter-based embolus removal system of the present invention is placed in a blood vessel, the embolus removal device is expanded and moved proximally along the blood vessel, so that the embolus is contained in a large amount in the basket of the embolus removal device. Specifically, the present invention provides a device / system and method for removing intracranial emboli without causing other distal complications, which are caused by the displacement of large fragments of thrombi that have regenerated distally from the initial thrombus location.

[0053] The terms "radially outward" and "radiating outward" as used herein refer to any direction that is not parallel to the central axis. Taking a cylinder as an example, a wire or a coil attached to or connected to the cylinder is radially outward with respect to the cylinder as long as the angle between it and the central longitudinal axis of the cylinder is greater than 0 degrees.

[0054] The term "lumen" as used herein refers to a cavity, a channel, usually tubular, or a cavity in the body, including veins, arteries, blood vessels, capillaries, intestines, etc. The term "lumen" may also refer to the tubular space within a catheter, microcatheter or other similar device.

[0055] As used herein, the term "proximal" refers to the end closest to the operator (less access to the body), and "distal" refers to the end farthest from the operator (more access to the body). From a downstream entry point, the distal end is further upstream and the proximal end is further downstream. "Proximal" and "proximal end" are used interchangeably, and "distal" and "distal end" are used interchangeably.

[0056] As used herein, the term "embolus" may refer to a clot, thrombus, or similar material, and these terms are used interchangeably.

[0057] The present invention provides various embodiments of medical devices / systems that can remove thrombi from blood vessels of the body. In some embodiments, the medical device / system may include an embolus capture device or a shape that is shaped to capture thrombi. In some embodiments, a push rod is connected to the embolus capture device. In some embodiments, the push rod can push and / or pull the thrombus capture device. In some embodiments, the thrombus capture device of the present invention may be elongated into an elongated profile during percutaneous delivery, return to a radially expanded state when capturing a thrombus, and be elongated into a second elongated profile when retrieving the thrombus. Unless otherwise specified, the term "vessel" used in this application refers to a blood vessel, including an artery, an arteriole, a capillary, a venule, a vein, or a combination of any of the above vessels.

[0058] In another aspect, the present invention discloses an intracranial thrombus capture device. According to some embodiments, the thrombus capture device has the characteristics of general stents being flexible, non-traumatic, of varying lengths and diameters, thin-walled, and / or radiopaque. In some embodiments, the stent can be precisely delivered, withdrawn, and repositioned. In some embodiments, the stent is soft enough to be delivered to small blood vessels via a microcatheter, but has sufficient radial support to conform to the geometry of the vessel wall when released.

[0059] In another aspect, the present invention discloses a thrombus capture device in an elongated delivery state. In some embodiments, the thrombus capture device has an expanded and released state. As described in detail below, in some embodiments, the thrombus capture device has a straight, elongated, small outer diameter shape suitable for delivery through a delivery system. In some embodiments, the thrombus capture device is placed in a blood vessel in a shape that allows it to fully contact the blood vessel. When the thrombus capture device of the present invention is used to remove a thrombus, a positioning guide wire is first passed through the thrombus in the blood vessel, and a microcatheter is delivered along the positioning guide wire to its distal end. After the distal end of the thrombus, the positioning guide wire is withdrawn; then a push rod connected to the proximal end of the elongated thrombus capture device is passed through the inner cavity of the microcatheter. While keeping the elongated thrombus capture device stationary, the clinician withdraws the microcatheter at the proximal end to release the thrombus capture device. Once the thrombus capture device is exposed from the microcatheter, it expands and contacts the thrombus. In one embodiment, the device is released to the distal end of the thrombus. In another embodiment, to remove a thrombus, the clinician pulls the push rod from the proximal end, and the thrombus capture device is pulled proximally with the thrombus into a larger catheter, a guide catheter, or a distal access catheter (DAC).

[0060] The delivery and placement techniques of the embodiments described herein are merely examples. Other techniques may also replace these techniques or be combined with these techniques. For example, the placement technique of an embodiment of the device described herein depends on the specific characteristics of the device, the delivery system, and the anatomical structure in which the device is placed.

[0061] In one aspect, the present invention provides a single-layer thrombus capture device. The thrombus capture device comprises a slender body. The slender body has a distal end, a proximal end, an axial cavity extending from the distal end to the proximal end, and an inner cavity surface; the inner cavity surface of the slender body has a plurality of capture units, each of which has a distal end, a proximal end, and a capture unit axis extending from the distal end to the proximal end. The capture unit axis of at least one capture unit forms an acute angle with the longitudinal axis of the slender body. The device is in a radially contracted state during transportation and in a radially expanded state during placement.

[0062] In another preferred embodiment, each capture unit on the inner surface of the thrombus capture device is composed of two pillars, and the pillar profile of at least one capture unit is different from the pillar profile of at least one other capture unit.

[0063] In another preferred embodiment, at least one capture unit is composed of two corrugated pillars, and the two corrugated pillars are symmetrical about the center of the capture unit axis, and the capture unit axis refers to the axis between the distal end and the proximal end of the capture unit.

[0064] In another preferred embodiment, the unit axes of all the capturing units on the cavity surface of the thrombus capturing device are parallel to each other.

[0065] In another preferred embodiment, each capture unit has a height and a length, and the ratio of the height to the length of at least one capture unit is different from that of at least one other capture unit.

[0066] In another preferred embodiment, the device rotates axially toward the distal end of the capture unit in a certain direction when expanding radially.

[0067] In another preferred embodiment, the device rotates axially in a left-handed manner.

[0068] In another preferred embodiment, the device rotates axially in a right-handed manner.

[0069] In another preferred embodiment, the device is axially rotated in a first direction and then axially rotated in a second direction while radially expanding, wherein the first direction is different from the second direction.

[0070] In another preferred embodiment, the device is axially rotated in a first direction and then radially expanded by axially rotating in a reverse direction.

[0071] In another preferred embodiment, the device is axially rotated at a first rotational speed and then radially expanded while being axially rotated at a second rotational speed.

[0072] In another preferred embodiment, the device is axially rotated at a first torque intensity and then axially rotated at a second torque intensity while radially expanding.

[0073] Another aspect of the present invention provides a double-layer thrombus capture device, which includes an outer slender body and an inner slender body. The outer slender body includes a distal end, a proximal end, an outer axial cavity extending from the distal end to the proximal end, and an outer cavity surface. The inner slender body includes a distal end, a proximal end, an inner axial cavity extending from the distal end to the proximal end, and an inner cavity surface. The inner slender body is in the axial cavity of the outer slender body, and the proximal ends of the inner slender body and the outer slender body are interconnected. The device is in a radially contracted state during transportation and in a radially expanded state during placement.

[0074] In another preferred embodiment, the inner cavity surface of the inner elongated body has a plurality of capture units. Each capture unit has a distal end, a proximal end, and a capture unit axis extending from the distal end to the proximal end. The capture unit axis of at least one capture unit forms an acute angle with the longitudinal axis of the elongated body.

[0075] In another preferred embodiment, the outer cavity surface of the outer elongated body has a plurality of capture units. Each capture unit has a distal end, a proximal end, and a capture unit axis extending from the distal end to the proximal end. The capture unit axis of at least one capture unit forms an acute angle with the longitudinal axis of the outer elongated body.

[0076] In another preferred embodiment, at least one of the inner elongated body and the outer elongated body is axially rotated during radial expansion.

[0077] In another preferred embodiment, the inner elongated body is axially rotated in a first direction and the outer elongated body is axially rotated in a second direction, wherein the first direction is different from the second direction.

[0078] In another preferred embodiment, the inner elongated body is axially rotated in a first direction and the outer elongated body is axially rotated in an opposite direction.

[0079] In another preferred embodiment, the inner elongated body is axially rotated at a first rotational speed, and the outer elongated body is axially rotated at a second rotational speed.

[0080] In another preferred embodiment, the inner elongated body rotates axially under a first torque intensity, and the outer elongated body rotates axially under a second torque intensity.

[0081] In another preferred embodiment, at least one of the inner elongated body and the outer elongated body is axially rotated in a first direction and then axially rotated in a second direction when radially expanding, wherein the first direction is different from the second direction.

[0082] In another preferred embodiment, at least one of the inner elongated body and the outer elongated body is axially rotated in a first direction and then axially rotated in an opposite direction during radial expansion.

[0083] In another preferred embodiment, at least one of the inner elongated body and the outer elongated body is axially rotated at a first rotational speed and then axially rotated at a second rotational speed while radially expanding.

[0084] In another preferred embodiment, the distal end portion of the inner elongated body is distal to the distal end portion of the outer elongated body.

[0085] The medical device provided by the present invention is inserted into a human blood vessel, for example, the device can be used to remove a thrombus. It should be noted that the present invention can also be applied to other medical devices. For example, stents, shunts, filters, etc. The device is particularly suitable for stent-like systems that can affect blood flow. The present invention is generally applied to implants or other medical devices that can be temporarily released in the body and can be recovered by a corresponding delivery system. Recyclability plays a great role in the repositioning of the device (such as a stent) or in the recovery of the device after a temporary release.

[0086] The present invention will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention. In addition, the accompanying drawings are schematic diagrams, so the device and apparatus of the present invention are not limited by the size or ratio of the schematic diagrams.

[0087] It should be noted that in the claims and description of this patent, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "including one" do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0088] Example

[0089] Figure 1The preset shape of a typical thrombus capture device (10) in the prior art after placement is shown. The thrombus capture device (10) is composed of a hollow slender body (12), which is generally cylindrical and has openings at both ends. The slender body (12) of the thrombus capture device (10) has a longitudinal axis "L", a distal end (16) and a proximal end (14). The proximal end (14) of the slender body (12) is connected to the distal end of the push rod (not shown) of the delivery system through several struts (18a, 18b). For example, two struts (18a, 18b) form an eccentric connection between the proximal end (14) of the device (10) and the distal end (16) of the push rod (8), such as Figure 2A In another embodiment, four struts (19a, 19b, 19c, 19d) form a balanced, more symmetrical connection between the proximal end (14) of the device (10) and the push rod (8), such as Figure 2B In one embodiment, the push rod (8) is fixed to the device (10). In another embodiment, the connection between the push rod (8) and the device (10) is detachable.

[0090] like Figure 1 As shown, the wall (cavity surface) of the device (10) is provided with an opening or a capture unit (20) (such as Figure 3 Each of the capture units (20) is laterally expanded and folded. The closed capture unit array structure of the thrombus capture device (10) allows the device (10) to shrink during transportation and expand during placement.

[0091] Figure 3 The structural design of a capture unit (20) of an embodiment is shown. As shown in the figure, each capture unit (20) includes two continuous wave rods (26, 28), and two points connecting the two wave rods (26, 28) form the distal end (24) and the proximal end (22) of the capture unit (20). The wave rods (26, 28) are preformed into an arc with a desired curvature. Figure 3 As shown, the wave bars (26, 28) are formed into the same arc shape and are symmetrical up and down. When the capture unit (20) is in a released state, the arcs of the two wave bars (26, 28) are separated from each other; when the capture unit (20) is folded, the distal end (24) and the proximal end (22) of each capture unit (20) are separated from each other so that the wave bars (26, 28) are straightened and approach each other.

[0092] It should be noted that the thrombus capture device claimed in the present invention may include Figure 3The capture unit (20) is formed by the wave rods of the same arc shape and symmetry in the upper and lower parts, but is not entirely composed of this type of capture unit (20). This type of capture unit (20) can be arranged at the proximal end of the cavity surface of the thrombus capture device of the present invention, and is used to connect with the push rod through the support, and can also be used as a connection medium between capture units of different arc shapes, etc.

[0093] Figure 4A A partial embodiment of the device (10) in an expanded state is described. Figure 4A As shown, several capture units (20a, 20b, 20c, 20d) are connected to each other in the longitudinal direction to form a row of capture units (30b). The capture unit rows (30a, 30b, 30c, 30d and 30e) have the same number of capture units and are arranged together in a radially offset manner. Figure 4A As shown, the capture unit (20a) at the closest end of row (30b) is also at the close end of the capture unit (21a) at the closest end of at least one adjacent row (30a); in turn, the capture unit at the farthest end of row (30b) is also at the close end of the capture unit (21e) at the farthest end of at least one adjacent row (30a). The proximal end of the capture unit (21a) in row (30a) starts at the maximum bending part of the capture unit (20a) in row (30b), and the distal end of the capture unit (20e) in row (30b) ends at the maximum bending part of the capture unit (21e) in row (30a). Therefore, each capture unit shares certain parts of the wave rod with the adjacent capture unit. For example, as Figure 4A As shown, the capture unit (20a) shares half of the wave rod with the capture unit (21a) and shares the other half of the wave rod with the capture unit (23a). This embodiment further shows two pillars (18a, 18b), whose distal ends are respectively connected to the proximal ends of the nearest capture units (20a, 25a), and their proximal ends are connected to each other and to the distal end of the push rod (not shown).

[0094] Figure 4A The five elements (30a, 30b, 30c, 30d, 30e) of the capture unit constitute the following Figure 1 In the device shown, specifically, row (30a) and row (30e) are connected together to form a horizontal axis "L" (such as Figure 1 As shown in FIG. Figure 1 In the exemplary embodiment shown, the device (10) has a longitudinal lumen and all of the capture units are expanded to a predetermined shape. Figure 1 The closed capture unit structure forms a complete cylindrical surface along the middle and distal portions of the device (10). The capture units in rows (30b) and (30d) form a partial cylindrical surface at the proximal end of the device (10).

[0095] Figure 4B Another embodiment is shown, the device (40) is in an expanded state, and has four pillars (19a, 19b, 19c, 19d) connected to its proximal end. In this embodiment, the device (40) is composed of 6 rows of capture units, and the arrangement of the capture units is the same as above. Figure 4A This embodiment further shows four pillars (19a, 19b, 19c, 19d), each end of which is connected to the proximal end (41a, 41c, 41e, 41g) of the nearest capture unit, and their proximal ends are connected to each other and to the distal end of the push rod (not shown). Figure 4B The rows (42a) and (42g) are connected together to form a horizontal axis "L" (such as Figure 1 As shown) device (40). Figure 4B As shown, in such a typical embodiment, the device (40) has a longitudinal lumen, and all the capture units are expanded to a predetermined shape. The closed capture unit structure forms a complete cylindrical surface along the proximal, middle and distal portions of the device (40).

[0096] The thrombus capture device claimed in the present invention can be Figure 4A or Figure 4B The pillar connection shown connects the capture unit and the push rod into one, but is not limited to this connection method.

[0097] According to some embodiments, a device with four connecting rods (i.e., "wave rods") at the proximal end generally has an even number of rows of capture units. A device with two connecting rods at the proximal end may have an even number of rows or an odd number of rows of capture units.

[0098] In another embodiment, for the convenience of describing various embodiments, the illustrations generally refer to a device with four connecting rods. It should be known by those skilled in the art that two connecting rods can be incorporated into a device with four connecting rods. In addition, for the convenience of describing the number of rows in the typical embodiment, it should be known by those skilled in the art that the number of rows can be appropriately increased or decreased depending on the purpose of the treatment.

[0099] Figure 3 An imaginary line connects the proximal and distal ends of each capture unit to form a capture unit axis (32). The capture unit also defines a height and a width. The capture unit length is the linear distance between the distal end (24) and the proximal end (22) of the capture unit (20), and its direction is parallel to the longitudinal axis "L". The capture unit height is the linear distance between the peaks of the upper and lower wave bars (28, 26), and its direction is perpendicular to the longitudinal axis "L". Figure 3In one embodiment shown, the wave rods (26, 28) have the same length and symmetrical arcs about the capture unit axis (32). In one embodiment shown in FIG. 4, the capture unit axis (32) is parallel to the longitudinal axis "L" of the device (10). Such a structure allows the wave rods (26, 28) of each capture unit to resume their arc shape when the device (10) is released from the delivery sheath, and at the same time, the distal end (24) and the proximal end (22) thereof move away from each other, and the arcs of the two wave rods (26, 28) move away from each other to cause the capture unit (20) to expand until it reaches its preset height and length. After the capture unit axis (32) is parallel to the longitudinal axis "L" of the device (10), each capture unit will expand in a direction perpendicular to the longitudinal axis "L", so that when the device (10) is placed in the body, it will expand uniformly in a radial direction perpendicular to the axis "L" without axial rotation along the longitudinal axis "L".

[0100] In one embodiment, the radial expansion of the thrombus capture device when placed is due to the elasticity of the material itself. In another embodiment, this radial expansion is achieved by pre-setting the thermal shape memory of the device material. In another embodiment, this radial expansion is achieved by manually expanding the balloon. In some embodiments, the thrombus capture device is made of stainless steel, nickel titanium, titanium, Elgiloy, cobalt-chromium-molybdenum alloy, Mobilium, Ticknium cast tooth alloy, Platinore, tungsten cobalt alloy, tantalum, platinum, Hastelloy corrosion-resistant nickel-based alloy, CoCrNi alloy (such as the trade name Phynox), MP35N, CoCrMo alloy or other metal alloys and mixtures thereof.

[0101] Figure 5A Another example of a capture unit (50a) is shown. In this example, the two wave rods (52, 54) forming the capture unit are equal in length and form a symmetrical arc across the unit axis. Figure 3Unlike the arrangement shown, the unit axis (55) is separated from the longitudinal axis "L" of the device by an angle of "ϴ" degrees. With this configuration, when the device is released from the delivery sheath, the distal and proximal ends (56, 58) of the capture unit (50a) move relative to each other, and the wave rods (52, 54) forming each capture unit (50a) resume their arc shape and move relative to each other, causing the capture unit (50a) to expand until the designed length and height are reached. Since the capture unit axis (55) is at an angle to the longitudinal axis "L", the expansion direction of the two wave rods (52, 54) is no longer perpendicular to the longitudinal axis "L" of the device. Therefore, instead of expanding in a direction perpendicular to the axis "L", one wave rod (52) of the capture unit expands away from the axis "L" at an angle of "ϴ1", while the other wave rod (54) of the capture unit expands at an angle of "ϴ2". As all the capture units around the cavity of the device (60) expand in the above-mentioned direction around the longitudinal axis "L", the device rotates around the axis "L" as it expands. Figure 5A and Figure 5B During the release of the capture unit shown, the device rotates in the radially distal direction of the capture unit. Figure 5A and Figure 5B In the illustrated embodiment, since the two wave bars forming the capture unit have the same width, thickness, length and the curvature of the two wave bars is centered, the axial rotational motion is performed in a sinusoidal manner. According to some embodiments currently described, the axial rotation angle per unit device length depends on the ratio of the device length to the circumference. According to one embodiment currently described, the rotation speed depends on the ratio of the capture unit height to length.

[0102] Those skilled in the art will appreciate that the capture unit configuration may vary from one embodiment to another, such as Figure 3 , 5A and 5B. According to some embodiments described in the prior art, the thickness and width of two wave bars forming the same capture unit may be different. According to some embodiments described in the present invention, the curvature of a single wave bar on one or both wave bars may not be centered, such as Figure 7 According to some embodiments described currently, Figure 3 As shown, the curvatures of the two wave rods (26, 28) are axisymmetric about the axis of the capture unit; Figure 5A As shown, the curvatures of the two wave rods (52, 54) are centrally symmetrical about the axis of the capture unit. According to another embodiment, Figure 7 As shown, the curvatures of the two wave rods (76, 78) are centrally symmetrical about the center point of the unit axis (75). According to some embodiments currently described, the height and length of each capture unit are the same, so the angle between the capture unit axis and the longitudinal axis "L" is about 45°. According to some embodiments currently described, the height and length of each capture unit are different, such as Figure 5AA change in one or more of these design criteria will result in a change in the torsional torque of the capture unit during extension.

[0103] According to some embodiments, the wave rod forming the capture unit may have a smooth single arc, such as Figure 3 , Figure 5A and Figure 5B In another embodiment, the wave rods (86, 88) forming the capture unit (80) may have a wave shape, such as Figure 8 As shown. This wave shape ensures that the device remains flexible when released at the treatment site and does not bend (or collapse) when passing through sharp bends, such as tortuous neurovascular pathways. According to the above description, the wave rods forming the capture unit do not have a curvature that is symmetrical about the capture unit axis. Instead, their wave rod curvature is radially symmetrical about the capture unit axis center.

[0104] Each of the above criteria may affect the capture unit release motion differently. For example, as the width and / or thickness of the wave bar increases, i.e., as the wave bar cross-section increases, the torque strength of the device during axial rotation increases. In another example, when the capture unit length to height ratio decreases, i.e., when the angle between the capture unit axis and the longitudinal axis "L" of the device increases, the axial rotation speed of the device increases. In another example, a device formed with relatively small capture units in the axial direction increases the stiffness and torque strength of the device during rotation. In another example, depending on the capture unit configuration, the device can rotate left or right along the axis during release. As shown in FIG. Figure 5A The catch unit (50a) shown will cause a left-hand rotation along the axis during release of the device. Figure 5B The catch unit (50b) shown will cause right-hand rotation along the axis during release of the device.

[0105] Those skilled in the art will appreciate that with different combinations of capture units and / or device designs, the device may be programmed with different motions, such as clockwise rotation, counterclockwise rotation, zigzag movement, acceleration and / or deceleration along the length of the device. Figure 3 , 5A The exemplary embodiments shown in 5B and 8 should not be considered to be limited to the scope of the present description.

[0106] Now mentioned Figure 1 , an array of identical capture units forms a device (10). Since the axes of all capture units are parallel to the longitudinal axis "L" of the device, when it is pushed out of the distal end of the delivery sheath and released, a portion of the device will expand radially without any twisting. Now, Figure 6, also an array of identical capture units forms a device (60). Since the axes of all capture units form the same angle with the longitudinal axis "L" of the device, when released, the device will expand radially while rotating uniformly at a stable speed.

[0107] According to some embodiments described herein, for example, Fig. 9 As shown, some of the capture units in the device (90) have different shapes from the other capture units. Fig. 9 As shown, the first capture element axis of the distal circumferential row (91a) of the first capture element forms a first angle (α1) with the longitudinal axis "L" (90) of the device, and the capture elements (91b) of the second circumferential row proximal to the first row (91a) have second capture element axes forming a second angle (α2) with the longitudinal axis "L" (90) of the device. With this configuration, when the device (90) is deployed, when the first row of capture elements (91a) is deployed, it will rotate to a first direction at a first speed, and then change to a second speed direction as the second row of capture elements (91b) is deployed.

[0108] According to some embodiments described herein, some capture units in the device may be of different sizes than the remaining capture units. Fig.10 As shown, the distal circumferential row (101a) of the first capture unit has a first capture unit size, and the second circumferential row (101b) of the first row (101a) has a second capture unit size. With this configuration, since the number of capture units in the distal circumferential row (101a) of capture units is different from that in the second circumferential row (101b) of capture units. Therefore, when the device (100) is expanded, the capture units of the first row (101a) are deployed, it will initially rotate in a first direction at a first speed and torque intensity, followed by a change in axial speed, torque intensity and toward another direction when the second row (101b) of capture units is deployed. According to one embodiment currently described, the axial speed gradually decreases when released.

[0109] Thus, according to some embodiments, the release motion of the device can be programmed by changing one or more of the above-mentioned design criteria. According to some embodiments, the angle between the capture unit axis and the longitudinal axis "L", the height and length ratio of each capture unit, the cross-section of each wave bar that makes up the capture unit, the length and height of each unit, the size of the capture unit, the curvature of the capture unit, and the cross-sectional profile of the wave bar can all be programmed to control the motion of the device. For example, in addition to the above-mentioned Fig. 9 and 10, the device can be rotated in a clockwise or counterclockwise direction by changing the distal orientation of each unit. In another example, the axial rotation torque strength of the device can be programmed by changing the cross-sectional profile of some of the capture unit's wave rods.

[0110] According to some embodiments currently described, the capture units of the device have a width of 1-10 mm and a height of 1-5 mm. Each unit is composed of a wave bar with a width and thickness of 0.001-0.010 inches. A device can have 2-6 rows of capture units, with 1-10 capture units in each row. When released, the diameter of the device can be 2 mm-8 mm and the length is 15 mm-60 mm. In another embodiment, the expansion rate of the diameter is 2-30. The angle between the axis of the device and the longitudinal axis "L" can be in any direction between 15-75 degrees. The device can be designed to be in a continuous left-hand rotation, a continuous right-hand rotation, or a torsional motion, such as left-hand rotation, right-hand rotation, and then left-hand rotation, etc.

[0111] While most existing solutions on the market rely on radial expansion of the device across the clot to capture the clot, the twisting and torque provided by the current description creates new forces and motions to increase the radial expansion of the device. Thus, the device not only engages the clot axially, but also radially. This allows the device to actively and safely engage and extract the clot.

[0112] like Figure 11-1 As shown in FIG3 , the thrombus capture device (110) has multiple layers of capture bodies with the same or different configurations. Fig.11 The multi-layered thrombus capture device (110) is illustrated in a released configuration with its proximal end connected to a push rod (8). Fig. 12A A hypothetical open view of the inner elongated body (120) and its capture unit configuration is shown. Fig. 12B The expanded profile of a single inner elongate body (120) is shown. Fig.13A A hypothetical capture unit configuration view of the outer elongated body (130) is shown. Fig. 13B The expanded profile of a single outer elongated body (130) is illustrated.

[0113] like Fig. 12A As shown, the inner elongated body (120) of the capture device (110) has four rows of identical capture units forming a complete perimeter of the main body and each row has four capture units. As shown, all capture units have the same size and cross-sectional support profile. Each capture unit, which is composed of two wave rods, has a distal end and a proximal end connected together. The wave curvature of each wave rod is Figure 8Similar to that described in . Each capture unit has an axis that forms the same angle "β1" with the longitudinal axis "L" of the inner elongated body. Two capture units between two adjacent rows share a portion of the same wave rod. Two capture units adjacent to the same row also share a portion of the same support. The four-connected wave rod is used to connect the proximal end of the inner elongated body to the delivery system, i.e., the push rod. According to one embodiment currently described, two adjacent wave rods are connected together to form a loop at the end of the wave rod. Another two adjacent wave rods (121a and 121b, 121c and 121d) also form a loop. The two loops are connected to the distal end of the delivery system (not shown). Fig. 12B The inner elongated body is illustrated in its deployed configuration, wherein the inner elongated body assumes a generally cylindrical shape having a longitudinal lumen and a distal opening. The proximal end of the inner elongated body is connected to a wave rod (not shown) configured to be attached to a delivery system. Figures 12A-12B As shown, when the inner elongated body is released, it expands radially, in a sinusoidal manner, and rotates leftward along the axis.

[0114] According to one embodiment of the present invention, the width of the wave bar forming each capture unit is about 0.0025 inches and the thickness is about 0.003 inches. When released, each capture unit has a length of 10 mm and a height of ¼ of the circumference. The angle between the capture unit axis and the longitudinal axis "L" of the device is about 30°.

[0115] See also Fig.13A The typical outer elongated body (130) of the capture device (110) is also formed by four rows of identical capture units to form a complete body circumference, with five capture units in each row. Fig. 12A , 12B The typical internal elongated body shown is similar to that of Fig.13A As can be seen, all capture units have the same size and profile. Each capture unit has two wave bars connected end to end at the proximal and distal ends. Each wave bar is as Figure 8 The wavy bend shown. Each capture unit has an axis that forms an angle β2 with the longitudinal axis "L" of the device. Capture units in two adjacent rows share a portion of the wave rod, and two adjacent capture units in the same row also share a portion of the wave rod. Four connected wave rods (131a&131b&131c&131d) connect the proximal end of the inner slender body to a conveying system such as a push rod, and these four connected wave rods (131a&131b&131c&131d) are connected at their distal ends to the proximal end of the nearest capture unit in each row. Fig. 13B The expanded structure of the outer elongated body (130) is described, in which the outer elongated body presents a preset cylindrical body having a longitudinal cavity and a distal opening. The proximal end of the outer elongated body (130) is connected to a wave rod connected to the delivery system. Figures 13A-13BIn the exemplary outer elongated body embodiment shown, when the outer elongated body (130) is released, it will expand radially and rotate sinusoidally right along the longitudinal axis. That is, when the device is released, the inner elongated body (120) and the outer elongated body (130) rotate in opposite directions.

[0116] According to one embodiment of the present invention, the width of the wave bar forming each capture unit is about 0.0025 inches and the thickness is about 0.003 inches. When released, each capture unit has a length of 10 mm and a height of ¼ of the circumference. The angle between the capture unit axis and the longitudinal axis "L" of the device is about 30°.

[0117] like Fig.11 As shown, when the device (110) is released at the treatment site, the inner elongated body (120) expands radially and rotates leftward along the axis, and the outer elongated body (130) expands radially and rotates rightward along the axis. When released, the length of the inner elongated body (120) (excluding the wave rod and extension rod connected at the proximal end) is 27.9 mm, and the length of the outer elongated body (130) is 32 mm. In this embodiment, the total length of the inner elongated body (120) and the wave rod and extension rod connected at the proximal end is 33 mm. Therefore, when released, the distal end of the inner elongated body will extend beyond the distal end of the outer elongated body when extending distally. In one embodiment, the expanded outer diameter of the elongated outer elongated body is about 5 mm, and the expanded outer diameter of the elongated inner elongated body is about 3 mm.

[0118] See also Fig.11 When treating a thrombus, the doctor pulls the proximal end of the push rod to retract the device to capture the thrombus and bring it back to the sheath. When the device collapses into the sheath, the inner elongated body (120) collapses radially and rotates right along the axis, and the outer elongated body (130) collapses radially and rotates left along the axis. According to one embodiment, this multi-layer device can improve the efficiency of thrombus treatment and recovery and improve the thrombus capture effect.

[0119] Those skilled in the art should understand Figure 11-1 3 only describes a typical embodiment of the multi-layer thrombus capture device. According to the above description, in particular Figure 3-10, each design variation can be combined to orchestrate the device release action and achieve optimal thrombus capture. For example, by adjusting the angle between the capture unit axis in the inner and outer elongated bodies and the longitudinal axis "L" of the device, the device can be orchestrated into the same or different axial rotation directions, the same or different axial movement lengths and rotation speeds. For example, by adjusting the size of the capture units in the inner and outer elongated bodies, the device can be orchestrated into the same or different torsional strengths. For example, the inner and / or outer elongated bodies can be orchestrated into a spiral rotational movement, such as starting with a left rotation, followed by a right rotation, then a left rotation, and so on. By arranging this embodiment of the different rotational structures of the inner and outer elongated bodies of the device, the device can further process and successfully capture thrombi.

[0120] According to some embodiments of the present invention, the length of the inner elongated body of the device can be kept the same as that of the outer elongated body. In another embodiment, the inner elongated body can be shorter than the outer elongated body so that the distal end of the inner elongated body is close to the distal end of the outer elongated body. Fig.11 As shown, the inner elongated body can be longer than the outer elongated body of the device, so that the distal end of the inner elongated body passes over the distal end of the outer elongated body. According to one embodiment of the present invention, when capturing a thrombus, the doctor withdraws the device into the sheath. When withdrawing the device, the inner elongated body and the outer elongated body will collapse radially while the device is retracted into the sheath. In one embodiment, when the device is withdrawn into the sheath, the elongated inner elongated body and the elongated outer elongated body rotate at different speeds along the axis. In another embodiment, when the device is withdrawn into the sheath, the elongated inner elongated body and the elongated outer elongated body rotate at the same speed along the axis.

[0121] According to some embodiments, the ratio of the diameters of the inner elongated body to the outer elongated body is 1:2 to 4:5, and the expansion rate of the outer elongated body is equal to or greater than the expansion rate of the inner elongated body.

[0122] According to some embodiments, the device is made of elastic material, superelastic material or shape memory alloy, so that the device can collapse into a completely straight contour during delivery, and restore and maintain its expected contour when released from the delivery sheath in vivo. In some embodiments, the device is made of stainless steel, nitinol, titanium, Elgiloy alloy, Vitalium alloy, Mobilium alloy, Ticonium alloy, Platinore alloy, Stellite alloy, tantalum, platinum, Hastelloy alloy, CoCrNi alloy, MP35N alloy, CoCrMo alloy, etc. In the above embodiments, part or all of the material of the device can be selected from any elastic, biocompatible material including but not limited to polyester cloth, Teflon-based materials such as ePTFE, UHMPE, HDPE, PP, PS, PU, ​​metal materials, PVA, extracellular matrix (ECM) separated from mammalian tissue or other bioengineering materials, bioabsorbable polymers such as polylactic acid, polyglycolic acid, polycaprolactone or other natural materials (such as collagen), or a combination of those well-known materials.

[0123] In some embodiments of the present invention, the device forms a pattern on a prefabricated tube by laser cutting or acid etching, and then shapes it into a desired set structure. In this embodiment, the capture unit is formed by a hollow tube, which is first slit by laser or water drilling or other methods and then expanded into an open structure. In another embodiment of the present invention, the grid is formed by wire, which is pre-bent into a target shape and then the constituent units are connected together by welding or bonding. Available welding methods include resistance welding and arc welding. It is recommended to weld in an inert gas environment with cooling control to control the lattice structure of the weld and its vicinity. After welding, these connection points can be processed by stamping or upsetting to reduce the grain size.

[0124] According to one embodiment of the present invention, the device is processed from a tube and formed into a final structure. In one embodiment, if a material with sufficient elasticity and shape recovery properties such as Nitinol is used, the structure can be prefabricated into the final shape, then elastically deformed and stowed during the push process, and the shape will recover after release.

[0125] Those skilled in the art will appreciate that the device of the present invention can be used simultaneously with the injection of drugs through the catheter directly to the thrombus. Those embodiments with a distal basket can limit the local effectiveness of drugs and act directly on the thrombus, such as tissue plasminogen activator (tPA) for dissolving thrombi. In particular, the distal basket of the device forms a closed space to prevent tPA from circulating with the system. Because this design can also block blood flow, it can prevent distal bleeding, drug injection, and blood aspiration. For example, a push rod can be configured to release tPA or any other therapeutic agent. In those embodiments with a distal basket, the space between the stent body and the basket, or the two caps, is configured to form a closed contour to prevent tPA from circulating in the system. In this case, after a period of time, the thrombus is dissolved by the drug and aspirated or removed by a thrombectomy device.

[0126] This typical embodiment shows a thrombus treatment device for thrombus removal without the aid of a microcatheter. Therefore, the use of the embodiments of the present invention can reduce vascular trauma, improve the effectiveness of twisting, improve the success rate of the operation, and reduce the possibility of thrombus in the twist.

[0127] According to one embodiment of the present invention, a developing marker, coil or wire can be wrapped around the elongated body to make the thrombus capture device visible under radiographic imaging equipment (such as X-ray, magnetic resonance, ultrasound or other imaging technology). The marker disclosed in the present invention can be applied to both ends of any part of the device, and even to the delivery system of the device. The developing marker can be sewn, adhered, crimped, riveted, or placed and fixed on the device. The developing marker can be made of tantalum, tungsten, platinum, iridium, gold, and alloys of these materials or other materials known to those skilled in the art. The developing marker can also be made of cobalt, fluorine or many other paramagnetic materials or other MR visible materials known to those skilled in the art.

[0128] In addition, the delivery system can also be designed for aspiration purposes. For example, the push rod is configured with a suction chamber. Such a chamber is opened during aspiration. When the distal end of the push rod is delivered to the treatment site, the doctor can connect a suction pump or a syringe to the hypotube and aspirate the thrombus. In some embodiments, the surface of the push rod with the suction chamber is cushioned to improve the suction effect.

[0129] Various embodiments are illustrated and described herein by way of examples, and those skilled in the art may find that various changes may be made without departing from the essence and scope of the present invention. The present invention is capable of other embodiments or of being practiced or executed in various other ways. In addition, it is to be understood that the terms and terminology used herein are intended to be illustrative and should not be considered limiting.

[0130] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the invention belongs. Methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention. In the event of a conflict, the invention specification, including definitions, will control. In addition, the materials, methods, and examples are illustrative only and not limiting.

Claims

1. A thrombus capture device, characterized in that: The thrombus capture device includes an outer elongated body, an inner elongated body and a push rod; The outer elongated body includes a distal end, a proximal end, and an outer axial lumen and an outer lumen surface extending from the distal end to the proximal end of the outer elongated body; The inner elongated body includes a distal end, a proximal end, and an inner axial lumen and lumen surface extending from the distal end to the proximal end of the inner elongated body; The inner elongated body is within the axial cavity of the outer elongated body, and the proximal ends of the inner elongated body and the outer elongated body are connected to each other, The push rod comprises a distal end and a proximal end; The proximal ends of the outer elongated body and the inner elongated body are connected to the distal ends of a plurality of struts, and the proximal ends of the plurality of struts are connected together and connected to the distal end of the push rod; The device is in a radially contracted state during transport and in a radially expanded state during placement; The outer cavity surface of the outer elongated body and the inner cavity surface of the inner elongated body are both provided with a plurality of capture units, each of the capture units has a proximal end and a distal end, and each of the capture units has a unit axis running through the distal end and the proximal end thereof; Wherein, the capture units of a first circumferential row along the outer cavity surface of the outer slender body and the inner cavity surface of the inner slender body have a first capture unit axis, and the first capture unit axis forms a first angle with the longitudinal axis of the slender body; the capture units of a second circumferential row of capture units adjacent to the first circumferential row have a second capture unit axis, and the second capture unit axis forms a second angle with the longitudinal axis of the slender body, and the first angle and the second angle are different; When the thrombus capture device is released, the outer elongated body and the inner elongated body expand radially and rotate in different directions along the longitudinal axis.

2. The thrombus capturing device according to claim 1, characterized in that: The proximal ends of the plurality of pillars are fixedly connected to the distal end of the pushing rod.

3. The thrombus capturing device according to claim 1, characterized in that: The proximal ends of the plurality of pillars are detachably connected to the distal end of the pushing rod.

4. The thrombus capturing device according to claim 1, characterized in that: The thrombus capture device is delivered to the treatment site via a microcatheter.

5. The thrombus capturing device according to claim 4, characterized in that: The device has a radially collapsed profile when delivered within the lumen of the microcatheter.

6. The thrombus capturing device according to claim 4, characterized in that: The device has a radially expanded profile when released out of the microcatheter.

7. The thrombus capturing device according to claim 1, characterized in that: The device has two struts, the distal ends of the two struts are connected to the proximal end of the elongated body, and the proximal ends of the two struts are connected together and to the distal end of the push rod to form an eccentric connection.

8. The thrombus capturing device according to claim 1, characterized in that: The device has four struts, the distal ends of the four struts are connected to the proximal end of the elongated body, and the proximal ends of the four struts are connected together and to the distal end of the push rod to form a balanced and symmetrical connection.

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