WO2023131311A2 - Thrombectomy stent, thrombectomy apparatus, and thrombectomy system - Google Patents

Abstract

Disclosed in the present invention are a thrombectomy stent, a thrombectomy apparatus, and a thrombectomy system. The thrombectomy stent comprises a first stent body and a second stent body; the second stent body is arranged at the distal end of the first stent body; the second stent body comprises a plurality of first pipe diameter segments and a plurality of transition segments; the first pipe diameter segments and the transition segments are alternately arranged in the axial direction of the thrombectomy stent, and two adjacent first pipe diameter segments are connected by means of a transition segment; when the proximal end and distal end of the thrombectomy stent are relatively far away from each other in the axial direction, at least a part of the region of each first pipe diameter segment radially shrinks, and the radial shrinkage regions of two first pipe diameter segments that are adjacent to each other in the axial direction are arranged at an angle. According to the present invention, when the thrombectomy stent captures a blood clot in a blood vessel and then is pulled, the thrombectomy stent can maintain a shape in different directions, and the whole thrombectomy stent does not obviously collapse; and the thrombectomy stent capable of maintaining the shape in different directions can increase the escape resistance of the blood clot, thereby being capable of effectively capturing the blood clots in different directions, and reducing the risk of blood clot escape.

Description

Thrombectomy stand, thrombectomy device and thrombectomy system technical field

The invention relates to the technical field of medical devices, in particular to a thrombectomy bracket, a thrombectomy device and a thrombus retrieval system.

Background technique

Thrombus is a blood clot formed by the abnormal aggregation of platelets and other formed components in the blood in the circulating blood. The blood clot may occur on the inner wall of the heart or on the wall of the blood vessel, causing blood vessel blockage or embolism, and secondary serious physical injury. Thrombosis spreads throughout the entire cardiovascular system, can occur in blood vessels anywhere in the body, and affects tissues and organs throughout the body, not limited to myocardial infarction, deep venous thrombosis, or cerebrovascular thrombosis. The incidence of venous thrombosis is higher than that of arterial thrombosis, the ratio of the two can reach 4:1, venous thrombosis accounts for 40% to 60% of the thrombus mechanism, the incidence of obstructive coronary thrombosis is 15% to 95%, and 90% of thrombus with Have atherosclerotic plaque. Thrombosis causes vascular occlusion and blockage of blood flow, leading to ischemia, hypoxia and even necrosis of related vascular innervated tissues, resulting in symptoms of corresponding tissue and organ dysfunction.

Anticoagulant drugs and thrombolytic drugs are often used clinically for treatment, but the therapeutic effect is very insignificant. The larger the diameter of the blood vessel blocked by the thrombus, the worse the therapeutic effect is, the recanalization rate is low, and the recanalization time is long, and some patients Not suitable for thrombolytic therapy.

At present, some mechanical devices are used to remove thrombus, which provides a new and efficient treatment method for blood vessel recanalization for patients with thrombosis. Mechanical thrombectomy has a short operation time and fewer related complications, and is currently a research hotspot in the field of thrombosis treatment; according to the current mainstream The shape and function of interventional thrombectomy devices can be divided into: spiral, screen type, brush type, suction type, and bracket type. The common defect of these mainstream products is that when passing through a curved blood vessel, the structure is easily deformed and collapsed. When withdrawing, the thrombus is easy to fall off at the curved blood vessel, and the thrombus escapes, causing varying degrees of damage to the blood vessel. The internal carotid artery, middle cerebral artery, vertebral artery, and basilar artery are the most common sites of nerve thrombus. The state of acute thrombus is mostly greasy and slippery. It is difficult to capture it completely with the existing metal thrombectomy stent.

Contents of the invention

An object of the present invention is to provide a thrombus retrieval bracket, a thrombus retrieval device and a thrombus retrieval system with improved thrombus capture performance.

In order to solve the problems of the technologies described above, the present invention adopts the following technical solutions:

According to one aspect of the present invention, the present invention provides a thrombectomy bracket, which includes a first bracket body and a second bracket body; the second bracket body is arranged at the distal end of the first bracket body; The second stent body includes a plurality of first diameter sections and a plurality of transition sections; the first diameter sections and the transition sections are arranged alternately along the axial direction of the thrombectomy stent, and two adjacent The first pipe diameter section is connected through the transition section; when the proximal end and the distal end of the thrombectomy bracket are relatively far apart in the axial direction, at least part of the first pipe diameter section shrinks radially, and axially The radial contraction regions of the two adjacent first pipe diameter sections are arranged at an angle.

According to another aspect of the present invention, the present invention also provides a thrombectomy device, which includes the above-mentioned thrombus retrieval bracket and a traction guide wire connected with the thrombus retrieval bracket; The proximal end of the thrombus support is connected to push and pull the thrombus retrieval support.

According to another aspect of the present invention, the present invention also provides a thrombectomy system, which includes the above-mentioned thrombectomy device, a push rod, a loading sheath, and a microcatheter; The proximal end is connected to push and pull the thrombectomy bracket; the loading sheath is used to accommodate the thrombectomy device in a compressed state; the microcatheter is used to communicate with the loading sheath, and the microcatheter The inner lumen is used to deliver the thrombectomy device.

It can be seen from the above technical solutions that the embodiments of the present invention have at least the following advantages and positive effects:

In the thrombectomy stent according to the embodiment of the present invention, the first diameter section can adapt to blood vessels of different diameters to ensure the wall-attachment performance of the blood vessel. On this basis, since the proximal and distal ends of the thrombectomy When they are far away, the two axially adjacent first pipe diameter sections are arranged at an angle in the radially contracted area, that is, the two axially adjacent first pipe diameter sections are not the same in the radially contracted part, and the radially contracted It is understandable that the region that has not shrunk in the radial direction is also dislocated, which means that when the thrombus retrieval stent is pulled after capturing the thrombus in the blood vessel, the thrombus retrieval stent can maintain its shape in different directions, and the overall shape of the thrombus retrieval stent There will be no obvious collapse, and the thrombus retrieval stent that can maintain its shape in different directions can increase the resistance of the thrombus to escape, and can also keep the thrombus retrieval stent in contact with the thrombus in vessels with different degrees of curvature, so that it can effectively Capture thrombus in different directions to reduce the risk of thrombus escape.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments of the present invention. For those skilled in the art, other drawings can also be obtained according to the structures shown in these drawings without creative effort.

Fig. 1 is a schematic structural view of a thrombectomy device according to an embodiment of the present invention;

Fig. 2 is a structural schematic diagram of the thrombectomy device shown in Fig. 1 after the relative deflection of 90 degrees in the circumferential direction;

Fig. 3 is a schematic structural view of the thrombectomy bracket of the thrombectomy device shown in Fig. 1 under axial tension;

Fig. 4 is a schematic structural view of the thrombectomy bracket of the thrombectomy device shown in Fig. 2 under axial tension;

Fig. 5 is a schematic cross-sectional view along section line II-II in Fig. 1;

Fig. 6 is a schematic cross-sectional view along the section line Ш-Ш in Fig. 1;

Fig. 7 is a schematic diagram of an enlarged structure at A in the thrombectomy device shown in Fig. 1;

Fig. 8 is a structural schematic diagram of the connection between the traction guide wire shown in Fig. 1 and the proximal end of the thrombectomy bracket;

Fig. 9 is a structural schematic diagram of another embodiment in which the traction guide wire is connected to the proximal end of the thrombectomy bracket;

Fig. 10 is a structural schematic diagram of another embodiment in which the traction guide wire is connected to the proximal end of the thrombectomy bracket;

Fig. 11 is a structural schematic diagram of the connection between the development guide wire shown in Fig. 1 and the distal end of the thrombectomy bracket;

Fig. 12 is a schematic structural view of the thrombectomy system including the thrombectomy device of Fig. 1 before assembly;

Fig. 13 is a structural schematic view of the bolt removing system of Fig. 12 when assembled and used;

Fig. 14 is a schematic diagram of the pushing state of the thrombectomy device in the thrombectomy system shown in Fig. 13;

Fig. 15 is a schematic diagram of the first state of the thrombectomy device shown in Fig. 1 during the thrombectomy process;

Fig. 16 is a schematic diagram of the second state of the thrombectomy device shown in Fig. 1 during the thrombectomy process;

Fig. 17 is a schematic diagram of the third state of the thrombectomy device shown in Fig. 1 during the thrombectomy process;

Fig. 18 is a schematic diagram of the fourth state of the thrombectomy device shown in Fig. 1 during the thrombectomy process;

Fig. 19 is a schematic diagram of the fifth state of the thrombectomy device shown in Fig. 1 during the thrombectomy process;

Fig. 20 is a schematic view from another perspective of the fifth state of the thrombus removing device shown in Fig. 19 .

Detailed ways

Typical embodiments that embody the features and advantages of the present invention will be described in detail in the following description. It should be understood that the present invention is capable of various changes in different embodiments without departing from the scope of the present invention, and that the description and illustrations therein are illustrative in nature and not limiting. this invention.

In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", " Orientation indicated by rear, left, right, vertical, horizontal, top, bottom, inside, outside, clockwise, counterclockwise, etc. The positional relationship is based on the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the application and simplifying the description, and does not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, Therefore, it should not be construed as limiting the application.

In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be interpreted as indicating or implying relative importance or implicitly specifying the quantity of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of said features. In the description of the present application, "plurality" means two or more, that is, two or more, unless otherwise specifically defined.

In the description of this application, it should be noted that unless otherwise specified and limited, the terms "installation", "connection", and "connection" should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection. Connected, or integrally connected; it can be mechanically connected or electrically connected; it can be directly connected or indirectly connected through an intermediary, and it can be the internal communication of two components. Those of ordinary skill in the art can understand the specific meanings of the above terms in this application in specific situations.

For the convenience of description and understanding, "proximal end" is defined herein as the end close to the operator, and "distal end" is defined as the end away from the operator. Specifically, the proximal end refers to an end for operation by a user or a machine, or an end for connecting to other devices. The distal end is the end of the device that can be freely inserted into the animal or human body.

The thrombectomy stent and the thrombus retrieval device provided by the embodiments of the present invention are used to dredge the blocked blood vessel and catch the thrombus in the blocked blood vessel when the blood vessel is blocked. The thrombectomy device includes a thrombectomy bracket and a traction guide wire, the traction guide wire is connected with the thrombectomy bracket and can be passed through the thrombectomy bracket. The thrombectomy stent has radial stretchability, so that the thrombectomy stent has a collapsed state and a natural expansion state. In the collapsed state, the thrombectomy stent can be easily delivered in the blood vessel through the microcatheter and delivered to the lesion site. When the lesion is reached, the microcatheter is withdrawn to restore the thrombus retrieval stent to its natural expansion state, and then cut and capture the thrombus in the lesion, and finally withdraw the thrombus retrieval stent with the thrombus, thereby removing the thrombus and realizing the occlusion of the blood vessel. dredge.

First please refer to FIG. 1 , a thrombectomy device 100 in this embodiment includes a thrombectomy support 1 and a traction guide wire 2 .

Wherein, the thrombectomy bracket 1 is roughly in the shape of a hollow tube, and its peripheral wall may be in a grid or mesh structure, and the grid or mesh structure may include regular or irregular hole-like structures. The traction guide wire 2 passes through the proximal end of the thrombectomy support 1 and is connected with the proximal end of the thrombectomy support 1 . The proximal end of the pulling guide wire 2 can be connected to the outside world. After the thrombus is captured, the pulling guide wire 2 is pulled to move toward the proximal end of the blood vessel, which can drive the thrombectomy stent 1 to retreat toward the proximal end of the blood vessel.

The thrombectomy support 1 has a collapsed state and a naturally expanded state. In the collapsed state, the radial dimension of the thrombectomy stent 1 is the smallest, which is convenient for delivery in blood vessels, so as to deliver the thrombectomy stent 1 to the lesion.

The thrombectomy stent 1 can be made of metal material with shape memory or elastic polymer material, so that the thrombectomy stent 1 can self-expand after being released into the blood vessel to form a roughly tubular or cage-like structure. Specifically, the thrombectomy stent can be formed by laser cutting a nickel-titanium tube, or by laser-cutting a nickel-titanium plate and then crimping and heat-setting, or braided, for example, braided by using nickel-titanium wire material, or Can be machined from elastic plastic material. When the thrombectomy stent 1 is released into the blood vessel and there is no radial external pressure, the thrombectomy stent 1 expands by itself, and the radial dimension becomes larger. In the naturally expanded state, the thrombus retrieval stent 1 stretches the thrombus at the lesion, and cuts the thrombus by using the grid or mesh structure on its peripheral wall, so that the thrombus is embedded in the thrombus retrieval stent 1 and is removed. Bracket 1 captures. Subsequently, pulling the pulling guide wire 2 to move toward the proximal end of the blood vessel can control the retraction of the thrombus retrieval stent 1 and the thrombus captured therein, and dredge the blocked blood vessel.

Referring to FIG. 1 and FIG. 2 , the thrombectomy bracket 1 includes a first bracket body 11 and a second bracket body 12 . The proximal end of the first stent body 11 is connected to the distal end of the traction guide wire 2, the distal end of the first stent body 11 is connected to the proximal end of the second stent body 12, and the first stent body 11 and the second stent body 12 are connected together. Forms a tubular structure that traps thrombus. When the thrombectomy stent 1 is withdrawn, the pulling guide wire 2 can more easily withdraw the second stent body 12 into the microcatheter through the first stent body 11 .

The second stent body 12 includes a plurality of first pipe diameter sections 121 and a plurality of transition sections 122, the first pipe diameter sections 121 and the transition sections 122 are arranged alternately along the axial direction of the thrombectomy stent 1, and the adjacent two first pipe diameter sections The radial sections 121 are connected by a transition section 122 . When the proximal end and the distal end of the thrombectomy bracket 1 are relatively far apart in the axial direction, that is, when the proximal end of the thrombectomy bracket 1 is retracted by a pulling force, at least part of the diameter of the first diameter section 121 is The radial contraction area of the two axially adjacent first pipe diameter sections 121 is arranged at an angle.

For a more detailed description, please compare Fig. 1 and Fig. 3, or compare Fig. 2 and Fig. 4, Fig. 1 and Fig. 2 are schematic diagrams of states of the thrombectomy bracket 1 in two different viewing angles before its proximal end is pulled , can also be understood as a schematic diagram of the state in which the thrombectomy stent 1 is completely freely expanded after being released into the blood vessel. In this state, the radial dimensions of each region in the circumferential direction of the first pipe diameter section 121 are approximately equal, that is, in the direction perpendicular to the longitudinal direction. In the transverse section, the distances from the periphery of the first pipe diameter section to the central axis of the first pipe diameter section are approximately equal, which means that the radial dimension difference of each area is within 5%, and two adjacent first pipe diameters The segments are relatively dislocated in the circumferential direction, and two adjacent transition segments are relatively dislocated in the circumferential direction. Fig. 3 and Fig. 4 are respectively schematic diagrams of the state of the thrombectomy support 1 shown in Fig. 1 and Fig. 2 in two different viewing angles after its proximal end is pulled, which can also be understood as the retraction to capture the thrombus. A schematic diagram of the state of the thrombectomy stent 1 . In this state, at least part of each first pipe diameter section 121 has obvious radial contraction, that is, radial collapse. In addition, the radial contraction areas of the two axially adjacent first pipe diameter sections 121 form a certain angle, which can be understood as the uncollapsed area or the collapse range of the two axially adjacent first pipe diameter sections 121 Relatively small areas are also angled.

In this embodiment, when the proximal end and the distal end of the thrombectomy stent 1 are relatively far apart in the axial direction, the radial contraction areas of the two axially adjacent first tube diameter sections 121 are relatively misaligned in the circumferential direction, for example, they are opposite to each other. The misalignment angle is 90 degrees, which can be understood as a 90-degree misalignment for regions with no significant change in radial size. The above structure of alternating displacement along the axial direction of the thrombectomy support 1 makes it easier for the thrombus retrieval support 1 to capture thrombus. It can be understood that, in other embodiments, the misalignment angle can also be set at other angles, which is not limited in the present application. For ease of understanding, the present application will take a 90-degree misalignment as an example for illustration.

5 and 6, FIG. 5 and FIG. 6 are schematic cross-sectional views of two adjacent first pipe diameter sections 121, respectively, the first pipe diameter section 121 has a first area 12a and a second area diametrically opposite to each other. 12b , and the third area 12c and the fourth area 12d oppositely arranged, the first area 12a , the third area 12c , the second area 12b , and the fourth area 12d are sequentially arranged along the circumferential direction of the second bracket body 12 . It should be noted that the "area" may include at least one of a point, a line, and a plane. When the proximal end and the distal end of the thrombectomy stent 1 move away from each other in the axial direction, the first region 12a and the second region 12b shrink radially, the third region 12c and the fourth region 12d maintain the same radial size, or the third The radially contracted size of the region 12c and the fourth region 12d is smaller than the radially contracted size of the first region 12a, and/or smaller than the radially contracted size of the second region 12b. In this embodiment, the first area 12a and the second area 12b can be understood as surfaces, and the third area 12c and the fourth area 12d can be understood as points or lines, that is, the third area 12c and the fourth area 12d are the first area 12a A point or a line intersecting with the second region 12b. That is, the first area 12a and the second area 12b are respectively diametrically opposite two side surfaces, and the third area 12c and the fourth area 12d are the confluence of the circumferential ends of the two side surfaces.

Wherein, when the first pipe diameter section 121 shrinks radially, the radial dimension of the radial contraction area of the first pipe diameter section 121 is smaller in the middle and larger at the two ends in the circumferential direction. That is, after the above-mentioned first region 12a and the second region 12b shrink radially, the radial size of the first region 12a and the radial size of the second region 12b gradually increase from the center to both sides until they are aligned with the third region 12c. It is equal to the radial dimension of the fourth region 12d.

The contraction law of the above regions can be understood as, in the two axially adjacent first pipe diameter sections 121 (Fig. 5 and Fig. 6), the first area 12a and the second At the same time, the area 12b is misaligned in the circumferential direction, and the angle of the misalignment is equal to the included angle of the misalignment of the radial contraction areas of the two first pipe diameter sections 121 , for example, the misalignment angle is 90 degrees. Moreover, the third area 12c and the fourth area 12d in the two first pipe diameter sections 121 are also misaligned in the circumferential direction, and the angle of the misalignment is equal to the gap between the radial contraction areas of the two first pipe diameter sections 121. Angle, for example, the misalignment angle is 90 degrees.

When the thrombectomy stent 1 is withdrawn by the traction guide wire 2, the proximal end of the thrombectomy stent 1 is subjected to a pulling force, and a partial area of the first diameter section 121 shrinks radially, that is, radially collapses. This can be represented by radial collapse of the above-mentioned first region 12a and second region 12b, while the radial dimensions of the third region 12c and fourth region 12d remain substantially unchanged, or vary within a small preset range. In this way, on the way of withdrawing the thrombectomy stent 1, even in an overbent blood vessel, the adherence performance of the third region 12c and the fourth region 12d to the blood vessel can always be maintained, and because the two axially adjacent first diameters The third area 12c of the section 121 is set at a 90-degree circumferential misalignment, and the fourth area 12d is set at a 90-degree circumferential misalignment, so that the thrombus caught by the thrombus retrieval stent 1 has an unsmooth escape channel and increased resistance, making it difficult to escape.

In the thrombectomy stent 1 of the embodiment of the present invention, the first diameter section 121 can adapt to blood vessels of different diameters and ensure the wall-attachment performance with the blood vessels. When moving relatively far away, the two axially adjacent first pipe diameter sections 121 are arranged at an angle in the radially contracted area, that is, the two axially adjacent first pipe diameter sections 121 are not the same in the radially contracted area , the radial contraction area is dislocated, and it can be understood that the radial contraction area is also dislocated, which means that when the thrombectomy stent 1 is pulled after capturing the thrombus in the blood vessel, the thrombectomy stent 1 can pass through the first tube The undeformed area of the diameter section 121 maintains its shape in different directions and improves the radial support force. The whole thrombectomy stent 1 will not collapse significantly, and the thrombus retrieval stent 1 that can maintain its shape in different directions increases the resistance of the thrombus to escape. , and can also enable the thrombus retrieval stent 1 to still maintain the contact area with the thrombus in blood vessels with different degrees of curvature, thereby effectively capturing thrombus in different directions and reducing the risk of thrombus escape.

In one embodiment, as shown in FIG. 1 and FIG. 7 , the transition section 122 includes a first support rod 123 and a second support rod 124 arranged at intervals along the circumference of the second bracket body 12 , and the first support rod 123 and the second support rod 123 The two support rods 124 extend along the axial direction of the thrombectomy bracket 1 and are arranged between the proximal and distal ends of two adjacent first tube diameter sections 121 facing each other. Based on the purpose of the present invention, the first support rod 123 and the second support rod 124 can not only be used as intermediate connectors between two adjacent first pipe diameter sections 121, but also can be used to drive the first pipe at one end to Radial deformation occurs in at least a partial area of the diameter segment 121 .

The two axially adjacent transition sections 122 are relatively misaligned in the circumferential direction, the two axially adjacent first pipe diameter sections 121 are relatively misaligned in the circumferential direction, and the two adjacent first pipe diameter sections 121 are relatively misaligned in the circumferential direction The angle is equal to the relative misalignment angle of two adjacent transition sections 122 in the circumferential direction. This means that the circumferential misalignment angle of two axially adjacent first support rods 123 is equal to the circumferential misalignment angle of two axially adjacent first pipe diameter sections 121 . In this embodiment, the first support rod 123 and the second support rod 124 are separated by 180 degrees in the circumferential direction, and the axially adjacent two first support rods 123 and the two second support rods 124 are circumferentially misaligned by 90 degrees respectively.

In this embodiment, the first pipe diameter section 121 includes a plurality of first corrugated parts 1211, and the plurality of first corrugated parts 1211 are sequentially connected end to end along the axial direction of the thrombus retrieval support 1, and two adjacent first corrugated parts 1211 forms a plurality of first meshes 101 arranged in the circumferential direction. In this embodiment, the shape of the first meshes 101 is a rhombus structure. Of course, in other embodiments, the first meshes 101 can also be meshes of other shapes. Structures, such as triangles, rectangles, or polygons, etc., are not limited in this application. For ease of understanding, Fig. 1 and Fig. 7 schematically show that the first pipe diameter section 121 has two first wave pieces 1211, and each first wave piece 1211 can be regarded as having a Z shape or a W shape by a plurality of rods. Shapes are arranged continuously and connected to form a closed-loop structure.

Each first wave element 1211 includes a plurality of crests and troughs, and the crests and troughs are arranged alternately in the circumferential direction. Specifically, the number of crests and the number of troughs of two adjacent first wave elements 1211 are equal, and the number of crests is equal to the number of troughs. In this paper, with reference to the orientations in Figure 1 and Figure 7, the near-end vertex is defined as the peak, and the far-end vertex is defined as the trough. Then the trough (i.e. the apex at the far end) of the first corrugated part 1211 at the proximal end in the first pipe diameter section 121 and the crest (i.e. the apex at the proximal end) of the first corrugated part 1211 at the far end converge and connect, and the first corrugated part 1211 at the proximal end The wave crests (i.e., the apexes at the proximal end) and the troughs (i.e., the apex at the distal end) of the first wave element 1211 at the distal end are axially opposite and far away from each other, so that the two first wave elements 1211 enclose and form a plurality of waves arranged at intervals in the circumferential direction. The first mesh 101 .

The first wave parts 1211 can expand and contract in the radial direction, so that adjacent peaks and adjacent wave troughs between each first wave part 1211 can approach or move away from each other. During natural expansion, the diameter of the first wave member 1211 becomes larger, and the axial interval between the crest and the trough becomes smaller, while the circumferential interval becomes larger. When the thrombus retrieval stent 1 reaches the thrombus in the lesion, the first corrugated part 1211 expands and opens, which can spread the thrombus, establish a blood flow channel, and realize the pre-passing function; and cut the thrombus through the first corrugated part 1211 , the cut thrombus partially enters the first wave member 1211 and is captured by the first mesh 101 .

The proximal end of the first support rod 123 and the proximal end of the second support rod 124 are connected with the apex of the first wave piece 1211 located at the distal end in the first pipe diameter section 121 adjacent to the proximal end, for example, connected with the first wave piece 1211 The proximal apex of the first corrugated member 1211 is connected, and the distal apex of the first corrugated member 1211 is free to hang in the air, so as to play the role of hooking the thrombus. Both the distal end of the first support rod 123 and the distal end of the second support rod 124 are connected to the apex of the first corrugated part 1211 located at the proximal end in the first pipe diameter section 121 adjacent to the distal end, for example, connected to the first corrugated part 1211. The proximal apex of piece 1211 is connected.

One of the two adjacent first tube diameter sections 121 located at the proximal end is defined as the proximal first tube diameter section 121 , and the other is the distal first tube diameter section 121 . In fact, in order to achieve the above purpose, the proximal end of the transition section 122 can be connected to part of the vertices of the proximal first pipe diameter section 121, while retaining part of the vertices of the proximal first pipe diameter section 121 as free endpoints, and the transition The distal end of the segment 122 is connected to all vertices of the distal first diameter segment 121 , leaving no free end points of the distal first diameter segment 121 . In this way, when the thrombectomy stent 1 is subjected to axial pulling force, it can ensure the uneven radial force of the first pipe diameter section 121 at the proximal end of the transition section 122, so as to realize the partial area of the first pipe diameter section 121 at the proximal end. radial shrinkage, while the other part of the region does not experience radial shrinkage. And at the same time, the uniformity of the force on the proximal end of the first distal pipe diameter section 121 in the radial direction is ensured. The uniformity of the radial force on the proximal end of the first distal pipe diameter section 121 can be the A pipe diameter section 121 provides supporting force to ensure localized radial contraction under the action of the next dislocated transition section 122 .

1 and 7, in one embodiment, the transition section 122 further includes a second pipe diameter section 125 and a plurality of support arms 126, and the plurality of support arms 126 are arranged at intervals along the circumference of the second support body 12, the first The proximal end of the two pipe diameter sections 125 is connected to the distal ends of the first support rod 123 and the second support rod 124, and the distal end of the second pipe diameter section 125 is connected to the first pipe diameter adjacent to the distal end through a plurality of support arms 126. The proximal connection of segment 121. In the naturally expanded state, the radial dimension of the first pipe diameter section 121 is larger than the second pipe diameter section 125. Such an arrangement not only ensures the flexibility of the thrombectomy support 1, but also makes the radial and axial direction of the thrombectomy support 1 It has a certain supporting force, and at the same time improves the capture efficiency of thrombus by the thrombus retrieval support 1 .

In this embodiment, the second pipe diameter section 125 includes a plurality of second corrugated parts 1251, and the plurality of second corrugated parts 1251 are sequentially connected end to end along the axial direction of the thrombus retrieval support 1, and two adjacent second corrugated parts 1251 forms a plurality of second meshes 102 arranged circumferentially. In this embodiment, the shape of the second mesh 102 is a rhombus-like structure, and herein, a rhombus-like structure is defined as a quadrilateral structure with at least two adjacent sides equal. Referring to Fig. 7, the shape of the second mesh 102 in this embodiment is that two groups of adjacent sides are respectively equal, that is, a group of adjacent sides located at the proximal end are equal, and a group of adjacent sides located at the far end are equal. Both sides are equal. It can be understood that, in other embodiments, the second mesh 102 may also be a mesh structure of other shapes, such as a triangle, a rectangle, or a polygon, etc., which are not limited in this application. For ease of understanding, Fig. 1 and Fig. 7 schematically show that the second pipe diameter section 125 has two second wave pieces 1251, and each second wave piece 1251 can be considered to be Z-shaped or W-shaped by a plurality of rods A closed-loop or non-closed-loop structure formed by continuous arrangement.

Each second corrugated part 1251 includes a plurality of crests and a plurality of troughs, and the second corrugated part 1251 can expand and contract in the radial direction, so that the adjacent crests and adjacent troughs between the second corrugated parts 1251 can be mutually move closer or farther away. During natural expansion, the diameter of the second wave member 1251 becomes larger, and the axial interval between the crest and the trough becomes smaller, while the circumferential interval becomes larger. When the thrombus retrieval stent 1 reaches the thrombus in the lesion, the second corrugated part 1251 expands and opens to expand the thrombus, establish a blood flow channel, and realize the pre-pass function; and cut the thrombus through the second corrugated part 1251 , the cut thrombus partially enters the second wave member 1251 and is captured by the second mesh 102 .

In one embodiment, referring to FIG. 7 , in the second tube diameter section 125, the second wave piece 1251 at the distal end continuously forms a closed-loop structure in the circumferential direction, and the second wave piece 1251 at the proximal end forms a discontinuous circle in the circumferential direction. non-closed structure. Specifically, the plurality of rods of the second wave member 1251 at the distal end extend continuously in a Z-shape or a W-shape in the circumferential direction, and the crests and troughs thereof are alternately arranged in the circumferential direction. The second wave member 1251 at the proximal end includes a plurality of wave units arranged at intervals in the circumferential direction, and the wave units may be V-shaped, Z-shaped, W-shaped, etc. formed by connecting a plurality of rods. The circumferential end of each wave unit of the proximal second wave element 1251 is discontinuous with adjacent wave units. In this embodiment, the second wave element 1251 at the proximal end of the second tube diameter section 125 includes two wave units spaced apart in the circumferential direction. The corrugated unit has an inverted V-shaped structure, including a proximal apex and two distal apexes, and each distal apex is converging with a corresponding wave crest in the second distal corrugated part 1251, thereby connecting with the distal second corrugated part 1251 A plurality of discontinuous second meshes 102 are jointly formed. Each wave-shaped unit of the proximal second corrugated part 1251 is not connected with other wave-shaped units, that is, there is an interval between adjacent wave-shaped units, thereby forming a larger hole than the second mesh 102 at the proximal end of the second pipe diameter section 125. Network port 102a. FIG. 7 shows that there are two second mesh holes 102 and mesh ports 102a and they are arranged alternately in the circumferential direction. The larger mesh opening 102a is beneficial to capture the escaped thrombus during the retraction process of the thrombus retrieval stent 1 so as to trap it into the thrombus retrieval stent 1 .

Continuing to refer to FIG. 7 , two adjacent second corrugated parts 1251 configured to form the second mesh 102 are defined as the proximal second corrugated part 1251 and the distal second corrugated part 1251 . The axial dimension of the proximal second undulating piece 1251 is smaller than the axial dimension of the distal second undulating piece 1251, so that the area of the second mesh 102 formed by adjacent two second undulating pieces 1251 is approximately in the axial direction. The end is small and the far end is large. In this way, based on the fact that the second wave piece 1251 at the proximal end is shorter in the axial direction and the second wave piece 1251 at the distal end is longer in the axial direction, the distance between the first pipe diameter section 121 and the second pipe diameter section 125 can be shortened. , increase the space for the thrombus retrieval stent 1 to catch the thrombus, making it easier for the thrombus to be embedded in the thrombus retrieval stent 1, which will enhance the anchoring effect on the thrombus block, and reduce the chance of the thrombus escaping, ensuring that the thrombus retrieval stent 1 can catch the thrombus. The efficiency of trapping thrombus is improved.

Both the proximal end of the first support rod 123 and the proximal end of the second support rod 124 are connected to the apex of the first wave piece 1211 at the far end in the adjacent first pipe diameter section 121, for example, to the top of the first wave piece 1211 The proximal apex is connected, and the distal apex of the first wave member 1211 can hang freely in the air, so as to hook the thrombus. Both the distal end of the first support rod 123 and the distal end of the second support rod 124 are connected to the apex of the second corrugated part 1251 located at the proximal end of the adjacent second pipe diameter section 125, for example, to the apex of the second corrugated part 1251 Proximal vertex connection.

The proximal end of the support arm 126 is connected to the apex of the second wave piece 1251 at the distal end of the second pipe diameter section 125, for example, connected to the proximal apex of the second wave piece 1251, and the distal apex of the second wave piece 1251 can be Free to hang in the air to play the role of hooking thrombus. The distal end of the support arm 126 is connected to the apex of the proximal first corrugated member 1211 in the distally adjacent first diameter section 121 , for example, connected to the proximal apex of the first corrugated member 1211 .

It should be noted that, it has been described above that along the axial direction of the thrombectomy stent 1, the proximal end of the transition section 122 is connected to the proximal apex of the first corrugated member 1211 adjacent to the proximal end. At this time, the first corrugated member 1211 The distal apex is suspended in the air as a free end, and the distal end of the transition section 122 is connected to the proximal apex of the first wave element 1211 adjacent to the distal end. It can be understood that, in other embodiments, the proximal end of the transition section 122 may also be connected to the distal apex of the first wave element 1211 adjacent to the proximal end; The distal apex of the first wave element 1211 is connected, and at this time, the proximal apex of the first wave element 1211 is suspended as a free end. It should be explained that the difference between the above two different design structures is that the transition section 122 between the two adjacent first pipe diameter sections 121 has been turned upside down (that is, along the direction from the proximal end to the distal end or the distal end to the proximal end), thereby changing the position and orientation of the free end point. Certainly, under the premise of considering the convenience of retracting the sheath of the stent 1 for thrombectomy, the preferred embodiment should be to set the free end point at the distal end of the first diameter section 121 .

For ease of understanding, this paper will use the preferred embodiment shown in FIG. 7 for expansion and description. In this embodiment, the proximal apex 1211a of the first corrugated member 1211 at the distal end of the first pipe diameter section 121 is a fixed apex, and the distal apex 1211b is a floating free terminal. Both the proximal apex 1211c and the distal apex 1211d of the first corrugated member 1211 located at the proximal end of the first diameter section 121 are fixed apexes. That is to say, the most distal end of the first pipe diameter section 121 forms a free end point.

The proximal apex 1251a of the second wave piece 1251 located at the distal end of the second pipe diameter section 125 is a fixed apex, and the distal apex 1251b of the second pipe diameter section 125 located at the distal end of the second wave piece 1251 is a suspended free end point. Both the proximal apex 1251c and the distal apex 1251d of the second corrugated member 1251 at the proximal end of the second tube diameter section 125 are fixed apexes. That is to say, the most distal end of the second pipe diameter section 125 forms a free end point.

The proximal end of the first support rod 123 and the proximal end of the second support rod 124 are connected with the proximal apex 1211a of the first wave piece 1211 located at the far end in the first pipe diameter section 121, and the distal end of the first support rod 123 and The distal end of the second support rod 124 is connected to the proximal apex 1251c of the second wave piece 1251 located at the proximal end in the adjacent second pipe diameter section 125 . The proximal end of the support arm 126 is connected to the proximal apex 1251a of the second wave piece 1251 located at the distal end of the second tube diameter section 125, and the distal end of the support arm 126 is connected to the proximal end of the adjacent first tube diameter section 121. The proximal vertices 1211c of a wave member 1211 are connected.

In one embodiment, referring to FIG. 7 , the distal free end point 1211b of the first pipe diameter section 121 extends toward the fixed vertices 1211a on both sides as the first catch unit 121a, and the first catch unit 121a is connected to the second catch unit 121a. A support rod 123 and a second support rod 124 are alternately arranged and connected to each other, and the first capture unit 121a may be V-shaped, W-shaped, zigzag or U-shaped to improve the efficiency of capturing thrombus. Fig. 7 shows that the number of first capturing units 121a is four, and the first support rod 123 and the second support rod 124 are opposite and located between two adjacent first capturing units 121a.

The part of the distal free end point 1251b of the second diameter section 125 extending toward the fixed vertices 1251a on both sides is used as the second catch unit 125a, and the second catch unit 125a and the support arms 126 are alternately arranged and connected to each other. The second capturing unit 125a may be in a V-shaped, W-shaped, zigzag or U-shaped structure, so as to improve the efficiency of capturing thrombus. FIG. 7 shows that the number of the second catch units 125a is four, and the second catch units 125a and the support arms 126 are arranged alternately along the circumferential direction.

It should be noted that a first receiving space 121 b is formed between the first catching unit 121 a and the first support rod 123 and between the first catching unit 121 a and the second support rod 124 . In order to enlarge the first receiving space 121b, the first catch unit 121a may extend radially outward or inward. A second receiving space 125b is formed between the second catching unit 125a and the supporting arm 126 . In order to enlarge the second receiving space 125b, the second catch unit 125a extends radially outward or inward. Preferably, both the first catch unit 121a and the second catch unit 125a extend radially outward or inward. More preferably, the bending direction of the first catching unit 121 a is opposite to that of the first support bar 123 and the second support bar 124 , and the bending direction of the second catching unit 125 a is opposite to that of the supporting arm 126 . In this way, the spaces between the first storage space 121b and the second storage space 125b are increased, thereby providing more accommodation space for the thrombus, so that the thrombus can enter the inner cavity of the thrombus retrieval support 1, thereby further improving the thrombus retrieval support 1 against thrombus. capture efficiency. When the thrombus retrieval stent 1 is in a free state (that is, in an expanded state), the first capture unit 121a and the second capture unit 125a are inserted into the thrombus, or clamp the thrombus in the first storage space 121b and the second storage space 125b Therefore, the anchoring effect of the thrombus retrieval support 1 on the thrombus is improved. Since the first capture unit 121a and the second capture unit 125a are evenly distributed around the second stent body 12, the flexibility of the thrombus retrieval stent 1 is enhanced, and the thrombus capture by the thrombus retrieval stent 1 is also improved. efficiency.

It should be noted that, in an embodiment, the thrombectomy support 1 described above also has the following characteristics, that is, the thrombectomy support 1 has a semi-free state and a free state. Wherein, the semi-free state (i.e. a partially released state) means that at least part of the structure of the thrombectomy stent 1 is in an incompletely expanded working state. The working state of thrombus compression, or the working state of the second stent body 12 of the thrombectomy stent 1 being constrained by other constraining elements. The free state (that is, the fully released state) means that the second stent body 12 of the thrombectomy stent 1 is in a fully expanded working state, or in a completely free (that is, not constrained by other constraining elements) working state.

In a semi-free state (not shown in the figure, you can refer to the drawings and descriptions of the patent application submitted by the applicant to the China Intellectual Property Office on May 30, 2020, the application number of which is 202010482816.8), The thrombectomy stent 1 is not fully expanded, and at least part of the structure of the second stent body 12 is approximately a single-layer tubular structure. In the free state, the thrombectomy stent 1 is fully expanded, and the second stent body 12 has an approximately double-layer tubular structure, and the radial dimension of the first diameter section 121 is greater than that of the second diameter section 125 .

In the process of switching from the free state to the semi-free state, the radial distance between the free end point of the distal end of the first tube diameter section 121 and the proximal apex of the second tube diameter section 125 adjacent to its distal end gradually decreases. The radial distance between the fixed apex of the proximal end of the first pipe diameter section 121 and the free end point of the distal end of the second pipe diameter section 125 adjacent to its proximal end gradually decreases. Thereby ensuring that the single-layer network structure has a smaller grid space.

Based on the fact that the thrombectomy bracket 1 has two states of semi-free and free, when the thrombectomy bracket 1 is in the semi-free state, at least part of the structure of the second bracket body 12 is an approximate single-layer tubular structure, and the mesh on the single-layer mesh structure The grid space is small, so as to avoid the blockage of the inner cavity caused by all the thrombus entering the inner cavity of the thrombectomy stent 1, so the single-layer tubular structure can be used as a blood flow channel. In addition, when the thrombectomy stent 1 is in a semi-free state, the single-layer tubular structure ensures the radial support force of the entire thrombus retrieval stent 1, so that the thrombus retrieval stent 1 can quickly establish a blood flow channel to recover before the thrombus is removed. Block the blood flow of the blood vessel, and then realize the pre-opening function of the blood flow channel in the early stage of thrombectomy, so as to improve the safety of the thrombectomy operation. Since the second bracket body 12 is in an approximately double-layer tubular structure in a free state, the first pipe diameter section 121 with a large pipe diameter has a larger grid structure, and the first pipe diameter section 121 and the second pipe diameter section 125 There is a certain space between them, so that all the thrombus can enter the inner cavity of the thrombus retrieval bracket 1, which improves the efficiency of thrombus retrieval. Further, the thrombectomy support 1 adopts a segmented design, that is, the first pipe diameter section 121 and the second pipe diameter section 125 are sequentially spaced and evenly arranged, so that the flexibility of the thrombectomy support 1 can be improved and the thrombectomy support can be ensured. 1. It can adapt to blood vessels with different curved shapes, and can also enhance the anchoring effect on thrombus. For example, when the blood vessel is squeezed, the thrombus retrieval stent 1 can withstand large deformation to conform to the shape of the blood vessel.

Herein, a plane parallel to the central axis of the thrombectomy support 1 is defined as a reference plane. In the free state, the orthographic projection of the first pipe diameter section 121 on a reference plane partly overlaps the orthographic projection of the second pipe diameter section 125 on the reference plane. In this way, the radial support force of the thrombus retrieval stent 1 in blood vessels of different diameters is ensured, thereby effectively preventing the thrombus retrieval stent 1 from collapsing when passing through the blood vessel, thereby improving the thrombus capture efficiency, and reducing the thrombus retrieval process. The damage caused by the thrombectomy stent 1 to the vessel wall. In the semi-free state, the orthographic projection of the first pipe diameter section 121 on the reference plane does not overlap with the orthographic projection of the second pipe diameter section 125 on the reference plane. In this way, when the thrombectomy stent 1 is in a partially released state, the overall structure or partial structure of the second stent body 12 is a single-layer tubular structure with an approximate closed-loop structure, and the metal coverage of the single-layer tubular structure is denser, thereby reducing thrombus entering the single-layer tubular structure. Inside the structure, the thrombectomy support 1 has a cavity for blood flow in a partially released state, which improves the safety of the thrombectomy operation.

In one embodiment, when the second support body 12 is in the semi-free state, the first support rod 123 , the second support rod 124 , and the support arm 126 are all straight rod-shaped structures. When the second support body 12 is in the free state, the first support rod 123 , the second support rod 124 , and the support arm 126 all have a curved structure, and are bent inward or outward relative to the second support body 12 . In this way, in the free state, since the first support rod 123 and the second support rod 124 are in a curved structure, the cutting of the thrombus can be reduced, and more accommodation space can be provided for the thrombus, so that the thrombus can enter and take out. The lumen of the thrombus stent 1 improves the capture efficiency of the thrombus by the thrombus retrieval stent 1 . In the semi-free state, since the first support rod 123 and the second support rod 124 are straight rod-shaped structures, and the first support rod 123 and the second support rod 124 are approximately parallel to the axial direction of the second support body 12 , so that the entire thrombectomy stent 1 can be compressed to form a single-layer tubular structure with approximately the same outer diameter in the axial direction and a closed-loop structure, so as to realize the pre-passing function of the blood flow channel and reduce brain damage during the operation.

1 and 2, the thrombectomy bracket 1 also includes a third bracket body 13 connected to the distal end of the second bracket body 12, the third bracket body 13 is connected to the second bracket body 12 in a smooth transition, and the third bracket body 13 It communicates with the inside of the second bracket body 12 so that the inside of the thrombus retrieval bracket 1 forms a continuous channel. The third stent body 13 can further catch the thrombus that falls off or overflows from the second stent body 12, so that the thrombus that falls off or overflows from the second stent body 12 can enter the internal channel of the third stent body 13, thereby effectively preventing the thrombus from being removed from the thrombus. Break away from the inside of the bracket 1 to improve the catching efficiency.

The third stent body 13 includes a catch section 131 and an extension section 132. The proximal end of the catch section 131 is connected to the second pipe diameter section 122 at the far end of the second stent body 12 through a plurality of support arms 126, and the distal end of the catch section 131 is connected to at the proximal end of the extension section 132. Wherein, the capturing section 131 has a plurality of third mesh holes 103 arranged along the circumferential direction, and the extension section 132 has a plurality of fourth mesh holes 104 arranged along the circumferential direction. The area of the third mesh 103 is larger than the area of the first mesh 101 , the area of the second mesh 102 and the area of the fourth mesh 104 . In addition, the distal ends of the extension sections 132 can converge with each other, so that the distal end of the thrombectomy stent 1 is closed to form the distal closed end of the thrombus retrieval stent 1, so as to prevent the thrombus captured in the thrombus retrieval stent 1 from being released from the closed distal end. escape. It can be understood that in other embodiments, the distal ends of the extension section 132 may not converge with each other, for example, the distal end of the extension section 132 is open, or, the distal end of the extension section 132 may be connected with a capture net.

It should be noted that the above-mentioned first bracket body 11, second bracket body 12 and third bracket body 13 can be integrally formed, thereby facilitating the manufacture of the bolt-removing bracket 1, and ensuring that the first bracket body 11, the second bracket body The stability and reliability of the mutual connection of the bracket body 12 and the third bracket body 13 . In some embodiments, the thrombus retrieval stent 1 can be processed by laser cutting a nickel-titanium tube material, so as to effectively prevent the thrombus from detaching from the thrombus retrieval stent 1 . The third bracket body 13 is arranged at the far end of the thrombus retrieval bracket 1, and the catch section 131 of the third bracket body 13 is provided with a plurality of third meshes 103 along the circumferential direction, and the extension section 132 of the third bracket body 13 is arranged along the circumferential direction. A plurality of fourth meshes 104 are provided, and the area of the third mesh 103 is larger than the area of the fourth mesh 104, so that both the large-volume thrombus and the small-volume thrombus escaping from the thrombus retrieval support 1 to the distal end can pass through the third mesh. The hole 103 enters the channel inside the third stent body 13 , and the extension section 132 accommodates the thrombus captured by the third stent body 13 , thereby further improving the capture efficiency of the thrombus retrieval stent 1 .

The extension section 132 includes a plurality of third wave parts 1321, and the plurality of third wave parts 1321 are sequentially connected end to end along the axial direction of the thrombus retrieval bracket 1, and two adjacent third wave parts 1321 form a plurality of circumferentially arranged. the fourth mesh 104. In this embodiment, the shape of the fourth mesh 104 is a rhombus structure. Of course, in other embodiments, the fourth mesh 104 can also be a mesh structure of other shapes, such as triangles, rectangles or polygons, etc., which are not limited in this application. . In addition, it should be noted that, in the direction from the proximal end to the distal end, the radial dimension of the third wave piece 1321 in the extension section 132 gradually decreases, which makes two axially adjacent third wave pieces 1321 surround The resulting fourth mesh 104 gradually becomes smaller in size. In this way, the resistance during the pushing process of the thrombectomy support 1 is reduced, and the recovery of the thrombectomy support 1 into the microcatheter is facilitated.

Each third wave element 1321 includes a plurality of crests and troughs, and the crests and troughs are arranged alternately in the circumferential direction. The third wave parts 1321 can expand and contract in the radial direction, so that adjacent wave crests and adjacent wave troughs between the third wave parts 1321 can approach or move away from each other. During natural expansion, the diameter of the third wave member 1321 becomes larger, and the axial interval between the crest and the trough becomes smaller, while the circumferential interval becomes larger. When the thrombus retrieval stent 1 reaches the thrombus in the lesion, the third corrugated part 1321 expands and opens to expand the thrombus, establish a blood flow channel, and realize the pre-passing function; and cut the thrombus through the third corrugated part 1321 , the cut thrombus partially enters the third wave member 1321 and is captured by the fourth mesh 104 .

Specifically, the capturing section 131 includes a plurality of reinforcing parts 1311 arranged along the circumferential direction of the third support body 13 , and the third mesh 103 is formed between two adjacent reinforcing parts 1311 . The reinforcing parts 1311 and the third mesh holes 103 are alternately arranged along the circumferential direction of the third support body 13 . Each reinforcing part 1311 includes a grid unit forming the fifth mesh 105 and a skeleton rod 106 disposed at a proximal end of the grid unit, and the proximal end of the skeleton rod 106 is connected with the distal end of the support arm 126 . In this embodiment, the area of the third mesh 103 is larger than the area of the fourth mesh 104 and the area of the fifth mesh 105, so that the escaped thrombus can be collected through the third mesh 103, and the collected thrombus can be prevented from being released by the third mesh 103. The fourth mesh 104 and the fifth mesh 105 escape.

Figures 1 and 2 illustrate that the number of third mesh holes 103 corresponds to the number of reinforcing parts 1311, and the third mesh holes 103 and reinforcing parts 1311 are arranged alternately along the circumference of the third bracket body 13. In this embodiment, the capturing section 131 includes two opposite third mesh holes 103 and two opposite reinforcing parts 1311, the third mesh holes 103 and the reinforcing parts 1311 are arranged side by side and alternately along the circumferential direction of the third bracket body 13 . In this way, not only the ability of the third mesh 103 to capture the thrombus that is not effectively captured by the second stent body 13 (such as hard thrombus such as organic thrombus, calcified thrombus, and thrombus with larger volume) is improved, but also the third mesh hole 103 is ensured. The radial support force of the stent body 13 avoids excessive deformation of the third stent body 13 and reduces the adherence of the capture section 131 , that is, prevents the capture section 131 of the third stent body 13 from collapsing.

In one embodiment, the skeleton rod 106 is configured in a Y-shaped configuration. For ease of understanding, with reference to Fig. 1 and Fig. 2, the skeleton rod 106 includes a first reinforcing rod 1061 and a second reinforcing rod 1062, and the second reinforcing rod 1062 is connected to the first reinforcing rod 1061 and the grid unit forming the fifth mesh 105 between. Wherein, the first reinforcing bar 1061 is configured into a V-shaped structure, and the V-shaped structure includes two near-end vertices and a far-end apex, the two near-end vertices are connected with the distal end of the support arm 126, and the far-end vertices are connected with the second reinforcing bar 1062. remote connection.

In one embodiment, the capturing section 131 is formed with a third capturing unit 103a at the proximal end of each third mesh hole 103, the proximal end of the third capturing unit 103a is connected to the distal end of the support arm 126, the third capturing unit The distal end of the catcher unit 103 a is configured as a free end and is located between two adjacent support arms 126 in the circumferential direction, or can be understood as located between two adjacent skeleton rods 106 . The third capture unit 103a may be V-shaped, W-shaped, zigzag or U-shaped, etc., to improve the efficiency of capturing thrombus. Fig. 1 and Fig. 2 illustrate that the third capturing unit 103a is V-shaped and there are two in number, and the two third capturing units 103a are arranged facing each other. When the thrombectomy support 1 was in a free state (i.e. in an expanded state), the axial length of the third catching unit 103a was no more than half of the axial length of the third mesh 103, so that the impact on the third mesh 103 could be reduced. The coverage ensures that the third mesh 103 provides a sufficiently large entrance for the escaping thrombus, thereby improving the capture efficiency of the thrombus.

It should be noted that the third catching unit 103a extends radially outward or inward to form an enlarged third receiving space 103b between the third catching unit 103a and the reinforcing portion 1311 . In this way, the third accommodation space 103b is enlarged, which can provide more accommodation space for the thrombus, so that the thrombus can enter the inner cavity of the thrombus retrieval stent 1 , thereby further improving the capture efficiency of the thrombus retrieval stent 1 . When the thrombus retrieval stent 1 is in a free state (that is, in an expanded state), the third capture unit 103a is inserted into the thrombus, or clamps the thrombus in the third accommodation space 103b, thereby improving the anchoring of the thrombus by the thrombus retrieval stent 1 Effect. Since the third capturing units 103a are evenly distributed in the circumferential direction of the third bracket body 13, the flexibility of the thrombus retrieval bracket 1 is enhanced, and the thrombus capture efficiency of the thrombus retrieval bracket 1 is also improved.

Referring to FIG. 8 , FIG. 8 illustrates a partial schematic diagram of the connection between the traction guide wire 2 and the proximal end of the thrombectomy bracket 1 in FIG. 1 . In one embodiment, the thrombectomy device further includes a proximal connector 14. The proximal connector 14 may be a hollow tubular structure with both ends open. The proximal end of the first bracket body 11 of the thrombectomy bracket 1 converges to the proximal The distal end of the connecting head 14 , for example, the proximal end of the first stent body 11 of the thrombectomy stent 1 can be adhesively fixed to the distal end of the proximal connecting head 14 .

The outer surface of the proximal connector 14 is provided with a first opening 141 communicating with the interior of the proximal connector 14, and the distal end of the traction guide wire 2 passes through the proximal end of the proximal connector 14 and is opposite to the first opening. When the window 141 is opened, the part of the distal end of the pulling guide wire 2 exposed to the first fenestration 141 can be fixed at a fixing head 21, and the fixing head 21 can be a welding joint or an adhesive joint. For example, in order to fix the distal end of the traction guide wire 2 to the proximal end of the thrombectomy bracket 1, the distal end of the traction guide wire 2 can be passed through the proximal end of the proximal connector 14, and the traction guide wire 2 can be The distal end is exposed to the first fenestration 141. At this time, the part of the traction guide wire 2 exposed to the first fenestration 141 can be fixed by welding or bonding, which is very convenient for the user to operate.

It should be noted that the fixed head 21 at the distal end of the traction guide wire 2 can be a spherical joint as shown in FIG. 8 , or a T-shaped joint as shown in FIG. The shapes in this application are only examples, not exhaustive, and thus should not be construed as limiting the application. In addition, with reference to Fig. 9 and Fig. 10, the expression form of the first window 141 can be as shown in Fig. 9 and Fig. the gap. Regardless of the appearance of the first opening 141 as a hole or a gap, the radial dimension of the fixing head 21 is smaller than the outer diameter of the proximal connecting head 14. Based on this, it can be avoided that the fixing head 21 exceeds the proximal connecting head 14 in the radial direction. Therefore, the radial protrusion of the fixing head 21 is avoided to increase the resistance of retracting the thrombus retrieval support 1 .

Referring to FIG. 11 , the thrombectomy device also includes a distal connector 15 and a developing guide wire 16. The distal end of the third bracket body 13 of the thrombus retrieval bracket 1 converges to the proximal end of the distal connector 15, and the distal connector 15 A second window 151 communicating with the interior of the distal connecting head 15 is opened on the outer surface. When the proximal end of the development guide wire 16 passes through the distal end of the distal connector 15 and is positioned at the second window 151, the part of the proximal end of the development guide wire 16 exposed to the second window can be mounted on the installation head (not shown in the figure). shown) is fixed. The installation head here can be understood as cured flux or adhesive, which can enter the interior of the distal connection head 15 through the second window 151 to be connected with the proximal end of the development guide wire 16 .

It should be noted that the developing guide wire 16 can be processed by memory alloy, platinum-tungsten alloy or silver-tin alloy. The setting of the developing guide wire 16 can conveniently indicate the position of the distal end of the third support body 13 of the embolectomy support 1 through the position of the developing guide wire 16 under instrument detection. The development guide wire 16 generally extends axially along the thrombectomy support 1, and the distal end of the development guide wire 16 is bent toward the inner side of the thrombectomy support 1, such as in a J shape. The damage of the free end of the guide wire 16 to the blood vessel is visualized.

Referring to FIG. 12 to FIG. 20 , the present invention also provides a thrombectomy system, which includes the thrombectomy device 100 , push rod 200 , loading sheath 300 , microcatheter 400 and sheath tube 500 in any one of the above embodiments.

Wherein, the push rod 200 is connected with the proximal end of the thrombectomy support 1 for pushing and pulling the thrombus retrieval support 1 . The loading sheath 300 is used to accommodate the thrombectomy device 100 in a compressed state. The microcatheter 400 is in communication with the loading sheath 300 , and the lumen in the microcatheter 400 is used to deliver the thrombectomy device 100 . The sheath tube 500 is sleeved outside the microcatheter 400, and the sheath tube 500 extends into the blood vessel along with the microcatheter 400, and is transported to the proximal end of the thrombus in the lesion, and is used to accommodate the thrombus retrieval stent 1 and its Captured thrombus.

For ease of understanding, the operation and use of the thrombectomy system will be described in detail below in conjunction with FIGS. 12 to 20 .

Please refer to Fig. 12 to Fig. 14 firstly, the thrombectomy device 100 according to the embodiment of the present invention is loaded in the thrombectomy system in a collapsed state before use, and the thrombectomy system includes the above-mentioned push rod 200, loading sheath 300, microcatheter 400 and sheath 500 (refer to FIG. 19 ).

The proximal end of the thrombus retrieval bracket 1 is converged and connected to the proximal connector 14 through the first bracket body 11, and the hollow proximal connector 14 communicates with the push rod 200. The push rod 200 is a flexible tube that can bend radially. The proximal end of the guide wire 2 passes through the proximal connector 14 and the push rod 200 in sequence.

The loading sheath 300 is sleeved on the outside of the push rod 200. Before use, the thrombectomy support 1 is pre-compressed and introduced into the loading sheath 300, as shown in FIG. 12 .

When thrombectomy is required, the loading sheath 300 can be connected to the microcatheter 400 through a connector 600 (such as a Luer connector), as shown in FIG. 13 . Then push the proximal connector 14 and the thrombectomy support 1 into the lumen of the microcatheter 400 smoothly through the push rod 200 , as shown in FIG. 14 . Afterwards, the thrombectomy device 100 is delivered to the vascular lesion position where the thrombus is located through the microcatheter 400 (the vascular lesion position can be determined according to angiography or other diagnostic means), so that the thrombectomy stent 1 can be released at the vascular lesion position and can be realized by the push rod 200. The push-pull action is accurately aligned, so that the thrombectomy support 1 can be switched between the compressed state and the released state.

The sheath tube 500 is sleeved outside the microcatheter 400, and is extended into the blood vessel along with the microcatheter 400, and delivered to the proximal end of the thrombus in the lesion, for receiving the thrombus retrieval stent 1 and the captured thrombus during withdrawal .

Please refer to FIG. 15 to FIG. 20 . In the interventional thrombectomy stent, referring to FIG. 15 , the perforated guide wire 700 is used to pass through the thrombus 01 in the lesion in advance to establish a vascular access in the thrombus. Referring to FIG. 16 , the microcatheter 400 and the sheath 500 are delivered along the perforated guide wire 700 to the thrombus 01 in the lesion, and the microcatheter 400 is passed over the thrombus 01 , then the microcatheter 400 is fixed, and the perforated guide wire 700 is withdrawn. Referring to FIG. 17 , the thrombus retrieval device 100 is pushed to the position of the thrombus 01 through the push rod 200 , and the position of the thrombus 01 can be determined by means of imaging or other diagnostic means. Referring to FIG. 18 , stop pushing the push rod 200 forward, fix the push rod 200 and retract the microcatheter 400, so that the thrombectomy support 1 is released at the distal end of the microcatheter 400, according to the position of the development point on the imaging guide wire 16 , to ensure that the thrombus 01 is located in the effective area of the thrombectomy device 100 , and to completely release the thrombus retrieval stent 1 in the blood vessel, so that the thrombus 01 is embedded in the thrombus retrieval stent 1 .

Referring to Fig. 19 and Fig. 20, pull the traction guide wire 2 and the push rod 200 at the same time, so as to withdraw the thrombus retrieval holder 1 with the thrombus 01 captured into the sheath tube 500, and complete the removal of the thrombus.

Referring to Fig. 19 and Fig. 20, during the retraction process of pulling the thrombectomy stent 1 by the traction guide wire 2, the first tube diameter section 121 can adapt to blood vessels of different diameters and ensure the wall-attachment performance with the blood vessels. On this basis, the shaft The two adjacent first pipe diameter sections 121 are arranged at an included angle in the region of radial contraction, that is, the two axially adjacent first pipe diameter sections 121 are not the same at the radial contraction part, and the radial contraction part The area is misaligned, and it can be understood that the area that does not shrink in the radial direction also has misalignment, which means that when the thrombus retrieval stent 1 is pulled after capturing the thrombus 01 in the blood vessel, the thrombus retrieval stent 1 can pass through the first diameter section 121 without The deformed area maintains its shape in different directions and improves the radial support force. The whole thrombectomy stent 1 will not collapse significantly. The thrombus retrieval stent 1 that can maintain its shape in different directions increases the resistance of the thrombus 01 to escape, and can The thrombus retrieval stent 1 still maintains the contact area with the thrombus 01 in blood vessels with different degrees of curvature, so that the thrombus 01 in different directions can be effectively captured and the risk of thrombus 01 escaping can be reduced.

While this invention has been described with reference to a few exemplary embodiments, it is understood that the terms which have been used are words of description and illustration, rather than of limitation. Since the present invention can be embodied in many forms without departing from the spirit or essence of the invention, it should be understood that the above-described embodiments are not limited to any of the foregoing details, but should be construed broadly within the spirit and scope of the appended claims. , all changes and modifications falling within the scope of the claims or their equivalents shall be covered by the appended claims.

Claims (31)

1. A thrombectomy bracket, characterized in that it comprises:

   the first bracket body;

   The second stent body is arranged at the distal end of the first stent body; the second stent body includes a plurality of first pipe diameter sections and a plurality of transition sections; the first pipe diameter sections and the transition sections are along the The thrombectomy brackets are arranged alternately in the axial direction, and the two adjacent first diameter sections are connected by the transition section; when the proximal end and the distal end of the thrombectomy bracket are relatively far apart in the axial direction, the At least a partial area of the first pipe diameter section is radially contracted, and the radially contracted areas of two axially adjacent first pipe diameter sections are arranged at an angle.
2. The thrombectomy bracket according to claim 1, characterized in that, the relative misalignment angle in the circumferential direction of the radially contracted areas of the two axially adjacent first tube diameter sections is 90 degrees.
3. The thrombectomy bracket according to claim 2, wherein the first pipe diameter section has a first area and a second area arranged radially opposite, and a third area and a fourth area arranged radially opposite, The first area, the third area, the second area and the fourth area are sequentially arranged along the circumferential direction of the second stent body;

   When the proximal end and the distal end of the thrombectomy stent move away from each other in the axial direction, the first region and the second region shrink radially, and the radial dimensions of the third region and the fourth region remain unchanged ; or the radially contracted size of the third area and the fourth area is smaller than the radially contracted size of the first area and/or the radially contracted size of the second area.
4. The thrombectomy bracket according to claim 2 or 3, characterized in that, when the first pipe diameter section radially shrinks, the radial size of the radial contraction area of the first pipe diameter section is in the middle of the circumferential direction. Small and big at both ends.
5. The thrombectomy bracket according to any one of claims 1 to 4, characterized in that the two axially adjacent transition sections are displaced relative to each other in the circumferential direction, and the two axially adjacent first pipe diameters The segments are relatively displaced in the circumferential direction, and the circumferential relative displacement angle of the two axially adjacent transition segments is equal to the circumferential displacement angle of the two axially adjacent first pipe diameter segments.
6. The thrombectomy bracket according to claim 5, wherein the transition section comprises a first support rod and a second support rod arranged at intervals along the circumference of the second bracket body, the first support rod and the second support rod The second support rod is arranged between the facing proximal and distal ends of two adjacent first pipe diameter sections.
7. The thrombectomy bracket according to claim 6, characterized in that, the first support rod and the second support rod are spaced apart by 180 degrees in the circumferential direction; the two axially adjacent transition sections are circumferentially displaced by 90 Spend.
8. The thrombectomy support according to claim 6 or 7, wherein the first pipe diameter section comprises a plurality of first wave parts, and the first wave parts are along the axial direction of the thrombectomy support. Connecting in sequence, two adjacent first corrugated parts form a plurality of first meshes arranged in the circumferential direction.
9. The thrombectomy bracket according to claim 8, characterized in that, both the proximal end of the first support rod and the proximal end of the second support rod are located far from the first pipe diameter section adjacent to the proximal end. The apex of the first corrugated piece at the end is connected, the distal end of the first support rod and the distal end of the second support rod are both adjacent to the distal end of the first wave section at the proximal end. Vertex connections of pieces.
10. The thrombectomy bracket according to claim 6 or 7, wherein the transition section further comprises a second pipe diameter section and a plurality of support arms, and the plurality of support arms are spaced circumferentially along the second bracket body arrangement, the proximal end of the second pipe diameter section is connected to the distal end of the first support rod and the distal end of the second support rod, and the distal end of the second pipe diameter section passes through the plurality of The support arm is connected to the proximal end of the adjacent first pipe diameter section;

    The thrombectomy stent has a semi-free state and a free state. In the semi-free state, the thrombectomy stent is not fully expanded, and at least part of the second stent body has a substantially single-layer tubular structure; In a free state, the thrombectomy stent is fully expanded, the second stent body has a substantially double-layer tubular structure, and the radial dimension of the first diameter section is larger than the radial dimension of the second diameter section.
11. The thrombectomy bracket according to claim 10, wherein in the free state, the orthographic projection of the first pipe diameter section on the reference plane is the same as the orthographic projection of the second pipe diameter section on the reference plane The projections partially overlap; in the semi-free state, the orthographic projection of the first pipe diameter section on the reference plane does not overlap the orthographic projection of the second pipe diameter section on the reference plane;

    Wherein, the reference plane is a plane parallel to the central axis of the thrombectomy bracket.
12. The thrombectomy bracket according to claim 10 or 11, wherein in the semi-free state, the first support rod, the second support rod and the support arm are all straight rod-shaped structures;

    In the free state, the first support rod, the second support rod and the support arm are in a curved structure and are bent radially inward or outward.
13. The thrombectomy bracket according to any one of claims 10-12, characterized in that, the first pipe diameter section comprises a plurality of first wave parts, and the plurality of first wave parts are along the side of the thrombectomy bracket. The axial end is connected in sequence, and two adjacent first corrugated parts form a plurality of first meshes arranged in the circumferential direction; the second pipe diameter section includes a plurality of second corrugated parts, and the plurality of corrugated parts Two second corrugated parts are connected end-to-end in sequence along the axial direction of the thrombectomy bracket, and two adjacent second corrugated parts form a plurality of second meshes arranged in the circumferential direction.
14. The thrombectomy bracket according to claim 13, characterized in that, the second corrugated part at the proximal end of the second pipe diameter section is discontinuous in the circumferential direction, so as to form a plurality of discontinuous second meshes in the circumferential direction. holes, and a mesh opening larger than that of the second mesh is formed at the proximal end of the second pipe diameter section.
15. The thrombectomy bracket according to claim 13 or 14, wherein the axial dimension of the second wave member at the proximal end of the second pipe diameter section is smaller than the second wave member at the distal end of the second pipe diameter section. The axial dimension of the corrugated member is such that the area of the second mesh formed by two adjacent second corrugated members is smaller at the proximal end and larger at the far end in the axial direction.
16. The thrombectomy bracket according to any one of claims 13-15, characterized in that, both the proximal end of the first support rod and the proximal end of the second support rod are adjacent to the first The apex of the first wave element at the far end in the pipe diameter section is connected, and the distal end of the first support rod and the distal end of the second support rod are both connected to the second pipe diameter section adjacent to the distal end. the apex connection of the second wave member located at the proximal end;

    The proximal end of the support arm is connected to the apex of the second wave element located at the distal end in the second pipe diameter section adjacent to the proximal end, and the distal end of the support arm is connected to the first pipe diameter section adjacent to the distal end. The vertices of the proximally located first wave members in the segments are connected.
17. The thrombectomy bracket according to claim 16, characterized in that, the proximal end of the first support rod and the proximal end of the second support rod are located far away from the first pipe diameter section adjacent to the proximal end. The proximal apex of the first corrugated piece at the end is connected, the distal end of the first support rod and the distal end of the second support rod are connected with the second pipe diameter section adjacent to the distal end, which is located at the proximal end. The proximal vertices of the two wave components are connected;

    The proximal end of the support arm is connected to the proximal apex of the second wave member whose proximal end is adjacent to the second pipe diameter segment located at the distal end, and the distal end of the support arm is connected to the distal end adjacent to the first wave element. A pipe diameter segment is connected to the proximal apex of the first wave element at the proximal end.
18. The thrombectomy bracket according to claim 17, wherein the proximal apex of the first corrugated part located at the distal end of the first pipe diameter section is a fixed apex, and the distal apex is a free end; the first tube Both the near-end apex and the far-end apex of the first corrugated member whose radial section is located at the proximal end are fixed apexes;

    The proximal apex of the second corrugated part at the far end of the second pipe diameter section is a fixed apex, and the distal apex of the second corrugated part at the far end of the second pipe diameter section is a free end point; Both the proximal apex and the distal apex of the second corrugated member whose pipe diameter section is located at the proximal end are fixed apexes.
19. The thrombectomy bracket according to claim 18, characterized in that, in the process of switching from the free state to the semi-free state, the free end point of the distal end of the first pipe diameter section adjacent to the distal end The radial distance between the proximal vertices of the second pipe diameter section gradually decreases;

    The radial distance between the fixed apex at the proximal end of the first pipe diameter section and the free end point at the distal end of the second pipe diameter section adjacent to its proximal end gradually decreases.
20. The thrombectomy bracket according to claim 18 or 19, characterized in that, the part of the distal free end point of the first pipe diameter section extending toward the fixed vertices on both sides is used as a first catching unit; The catching unit is arranged alternately with the first support rod and the second support rod and connected with each other;

    The part of the distal free end point of the second pipe diameter section extending toward the fixed vertices on both sides is used as a second catch unit; the second catch unit is arranged alternately with the support arms and connected to each other.
21. The thrombectomy bracket according to claim 20, wherein the first capture unit extends radially outward or inward to increase the distance between the first capture unit and the first support rod. The first accommodation space between the first catch unit and the second support rod; the second catch unit extends radially outward or inward to increase the The second accommodation space between the capture unit and the support arm.
22. The thrombectomy bracket according to any one of claims 13-21, wherein the thrombus retrieval bracket further comprises a third bracket body connected to the distal end of the second bracket body, the third bracket body and The interior of the second bracket body communicates with each other, so that the interior of the thrombectomy bracket forms a continuous channel;

    The third stent body includes a capture section and an extension section, the proximal end of the capture section is connected to the second pipe diameter section at the distal end of the second stent body through the plurality of support arms, the capture section The distal end is connected to the proximal end of the extension section; wherein, the capture section has a third mesh hole arranged circumferentially, and the area of the third mesh hole is larger than the area of the first mesh hole and the first mesh hole. The area of the second mesh.
23. The thrombectomy bracket according to claim 22, wherein the extension section comprises a plurality of third wave parts, and the plurality of third wave parts are connected end to end in sequence along the axial direction of the thrombectomy bracket, Two adjacent third wave parts form a plurality of fourth meshes arranged in the circumferential direction; the distal ends of the extension sections converge to each other, so that the distal ends of the thrombectomy bracket are closed to form the thrombectomy The distal closed end of the stent.
24. The thrombectomy bracket according to claim 23, wherein the capturing section includes a plurality of reinforcing parts arranged along the circumferential direction of the third bracket body, and two adjacent The third mesh holes are formed between the reinforcement parts, and the reinforcement parts and the third mesh holes are alternately arranged along the circumferential direction of the third bracket body; each reinforcement part includes a fifth mesh hole grid unit and a skeleton rod arranged at the proximal end of the grid unit, the proximal end of the skeleton rod is connected to the corresponding distal end of the support arm; the area of the third mesh is larger than that of the fourth mesh The area of the hole and the area of the fifth mesh.
25. The thrombectomy bracket according to any one of claims 22-24, characterized in that, the capture section has a third capture unit formed at the proximal end of each third mesh, and the third capture unit The proximal end of the unit is connected to the distal end of the corresponding support arm; the distal end of the third catching unit is configured as a free end and is located between two adjacent support arms.
26. The thrombectomy bracket according to claim 25, wherein the third capturing unit extends radially outwards or inwards to increase the second distance between the third capturing unit and the adjacent portion in the circumferential direction. Three containment spaces.
27. A thrombectomy device, characterized in that it comprises the thrombectomy bracket according to any one of claims 1 to 26 and a traction guide wire connected to the thrombectomy bracket;

    The traction guide wire is connected to the proximal end of the thrombectomy support for pushing and pulling the thrombectomy support.
28. The thrombectomy device according to claim 27, wherein the thrombus retrieval device further comprises a proximal connector, the proximal end of the thrombus retrieval bracket converges to the distal end of the proximal connector; the proximal The outer surface of the terminal connector is provided with a first window communicating with the interior of the proximal connector;

    When the distal end of the traction guidewire passes through the proximal end of the proximal connector and is positioned against the first fenestration, the part of the distal end of the traction guidewire exposed to the first fenestration can be Fix at the fixed head.
29. The thrombectomy device according to claim 27 or 28, characterized in that, the thrombus removal device further comprises a distal connector and a developing guide wire, and the distal end of the thrombus removal bracket converges to the distal connector. Proximity; the outer surface of the distal connector is provided with a second window communicating with the interior of the distal connector;

    When the proximal end of the developing guidewire passes through the distal end of the distal connector and is positioned against the second fenestration, the portion of the proximal end of the developing guidewire exposed to the second fenestration can be Fastened at the mounting head.
30. The thrombectomy device according to claim 29, wherein the imaging guide wire extends along the axial direction of the thrombus retrieval bracket, and the distal end of the imaging guide wire is bent toward the inside of the thrombus retrieval bracket.
31. A thrombectomy system, characterized by comprising a push rod, a loading sheath, a microcatheter, and the thrombectomy device according to any one of claims 27 to 30;

    The push rod is connected to the proximal end of the thrombectomy bracket for pushing and pulling the thrombectomy bracket;

    The loading sheath is used to accommodate the thrombectomy device in a compressed state;

    The microcatheter is used to communicate with the loading sheath, and the lumen in the microcatheter is used to deliver the thrombectomy device.

Images