Self-expanding thrombus stent

Abstract

The present invention provides a self-expanding thrombus stent, comprising: a string-type stent, comprising a plurality of stent units connected in series, each stent unit being a telescopic stent body, capable of adjusting the shape and volume of the stent unit by contraction and expansion, the stent units being open at both ends and hollow inside; a catheter, penetrating the string-type stent, one end of the string-type stent being fixed to the catheter, the other end forming an operating end, and being movably connected to the catheter, when the operating end is pushed or pulled back along the catheter, the stent unit expands into a sphere, or contracts into an olive shape; wherein the surface of the stent unit is hollow, so that the stent unit can wrap the thrombus when it expands into a sphere after being inserted into the thrombus, and can stably carry the thrombus out of the blood vessel as the string-type stent and the catheter move after contraction into an olive shape. The self-expanding thrombus stent of the present invention can expand itself to wrap the thrombus after being inserted into the blood vessel, thereby assisting medical personnel in removing the thrombus from the blood vessel.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of medical devices, and in particular to a self-expanding thrombus stent. Background Art

[0002] Thrombi are small pieces of blood formed on the surface of peeling or repairing parts of the cardiovascular system. Among them, intravascular thrombosis in coronary arteries is a type of ischemic acute myocardial infarction, which often has an acute onset and a high mortality rate. Coronary thrombosis is more common in middle-aged and elderly people and now tends to develop in young people. It is mainly caused by vascular atherosclerosis. When patients have coronary thrombosis, they often need to use a suction catheter for suction. However, the effect is often not ideal, and the probability of thrombus detachment during the suction process should not be underestimated, which increases the patient's risk of stroke. Summary of the invention

[0003] The invention provides a self-expanding thrombus stent which can be extended into a blood vessel and then expand into a sphere to wrap the thrombus, thereby assisting medical personnel to remove the thrombus from the blood vessel.

[0004] In order to solve the above technical problems, an embodiment of the present invention provides a self-expanding thrombus stent, comprising:

[0005] A series-type bracket, comprising a plurality of bracket units connected in series, each of which is a telescopic bracket body, which can adjust the shape and volume of the bracket unit by contraction and expansion, and the bracket unit is open at both ends and hollow inside;

[0006] A catheter passes through the string-type stent, one end of the string-type stent is fixed to the catheter, and the other end forms an operating end and is movably connected to the catheter. When the operating end is pushed or pulled back along the catheter, the stent unit swells to form a sphere, or contracts to form an olive shape;

[0007] The surface of the stent unit is hollowed out so that the stent unit can fully wrap the thrombus when it is extended into the thrombus and then swells into a sphere, and can stably carry the thrombus out of the blood vessel as the string-type stent and catheter move after shrinking into an olive shape.

[0008] In some embodiments, when the plurality of series-connected stent units are expanded to form spheres, at least some of the spheres have different inner diameters.

[0009] In some embodiments, the plurality of series-connected stent units are divided into three parts, each part includes one or more stent units with the same inner diameter, and stent units belonging to different parts have different inner diameters.

[0010] In some embodiments, in the direction in which the string-type stent extends into the blood vessel, the inner diameters of the stent units in the three parts gradually increase.

[0011] In some embodiments, in the direction in which the string-type stent extends into the blood vessel, there are sequentially a first part, a second part and a third part, the inner diameter of the stent unit of the first part ranges from 1.5mm to 2.5mm, the inner diameter of the stent unit of the second part ranges from 2.0mm to 3.0mm, and the inner diameter of the stent unit of the third part ranges from 3.0mm to 4.0mm.

[0012] In some embodiments, the string-type stent includes a plurality of axially arranged first ribs, one end on the same side of the plurality of first ribs is connected to a first annular fixing ring, the first fixing ring is fixed on the catheter, the other ends on the same side of the plurality of first ribs are cooperated and wound around the catheter to form the operating end, a plurality of second annular fixing rings for restraining the plurality of first ribs are arranged at intervals in the middle of the plurality of first ribs, and the plurality of first ribs between two adjacent second annular fixing rings and between the first annular fixing ring and the adjacent second annular fixing ring form the skeleton of the stent unit.

[0013] In some embodiments, a plurality of elastic and annular second ribs are provided on the plurality of first ribs forming the skeleton. When the operating end is pushed to expand the first ribs, the plurality of second ribs are elastically propped up without the restraining effect of the first ribs, thereby making the bracket unit spherical. When the operating end is pulled back to tighten the first ribs and lean against the catheter, the plurality of second ribs are compressed and contracted by the radial restraining force of the first ribs, thereby making the bracket unit olive-shaped.

[0014] In some embodiments, the second ribs are surrounded by wavy or zigzag elastic members, and a plurality of the second ribs are arranged in parallel and at intervals;

[0015] The preparation materials involved in the string-type stent are all Nitinol alloy.

[0016] In some embodiments, an outer catheter is further included, wherein the string-type stent is inserted into the outer catheter, and each stent unit is expanded to be a sphere when the outer catheter is extended, and each stent unit is contracted to be an olive shape when the outer catheter is retracted;

[0017] The top cover of the conduit is provided with a fixing cap for stopping the string-type bracket.

[0018] In some embodiments, a hydrophilic layer is disposed on the outside of the outer catheter, and a lubricating layer is disposed on the inside of the outer catheter.

[0019] Based on the disclosure of the above embodiments, it can be known that the beneficial effects possessed by the embodiments of the present invention include that the self-expanding thrombus stent has a simple overall structure and is easy to prepare, which can be achieved by only setting up a catheter and a string-type stent, wherein the string-type stent can move relative to the catheter to expand into a spherical shape or contract into an olive shape, and the string-type stent can penetrate the thrombus and then wrap the thrombus by operating it, and can carry the thrombus out of the blood vessel as the string-type stent extends out of the blood vessel, thereby achieving the effect of clearing the thrombus quickly and effectively.

[0020] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the written description, claims, and drawings.

[0021] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0023] Figure 1 Schematic diagram of the structure of a self-expanding thrombus stent in an embodiment of the present invention.

[0024] Figure 2 FIG. 4 is another schematic diagram of the structure of a self-expanding thrombus stent in an embodiment of the present invention.

[0025] Figure 3 It is a schematic structural diagram of a self-expanding thrombus stent in another embodiment of the present invention.

[0026] Reference numerals:

[0027] 1- string type bracket; 2- bracket unit; 3- catheter; 4- first rib; 5- second rib; 6- first annular fixing ring; 7- second annular fixing ring; 8- outer catheter; 9- operation end. DETAILED DESCRIPTION

[0028] The specific embodiments of the present invention are described in detail below with reference to the accompanying drawings, but are not intended to limit the present invention.

[0029] It should be understood that various modifications may be made to the embodiments disclosed herein. Therefore, the following description should not be considered as limiting, but merely as an example of an embodiment. Other modifications within the scope and spirit of the present disclosure will occur to those skilled in the art.

[0030] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the present disclosure and, together with the general description of the present disclosure given above and the detailed description of the embodiments given below, serve to explain the principles of the present disclosure.

[0031] These and other characteristics of the invention will become apparent from the following description of a preferred form of embodiment given as a non-limiting example, with reference to the accompanying drawings.

[0032] It should also be understood that, although the invention has been described with reference to some specific examples, those skilled in the art will be able to realize many other equivalent forms of the invention that have the characteristics recited in the claims and are therefore within the scope of protection defined thereby.

[0033] The above and other aspects, features and advantages of the present disclosure will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.

[0034] Specific embodiments of the present disclosure are described hereinafter with reference to the accompanying drawings; however, it should be understood that the disclosed embodiments are merely examples of the present disclosure, which may be implemented in a variety of ways. Well-known and / or repeated functions and structures are not described in detail to avoid obscuring the present disclosure with unnecessary or redundant details. Therefore, the specific structural and functional details disclosed herein are not intended to be limiting, but merely serve as a basis and representative basis for the claims to teach those skilled in the art to use the present disclosure in a variety of ways with substantially any suitable detailed structure.

[0035] This specification may use the phrases "in one embodiment," "in another embodiment," "in a further embodiment," or "in other embodiments," all of which may refer to one or more of the same or different embodiments according to the present disclosure.

[0036] The embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0037] like Figure 1 and Figure 2 As shown, an embodiment of the present invention provides a self-expanding thrombus stent, comprising:

[0038] The string-type bracket 1 comprises a plurality of bracket units 2 connected in series, each of the bracket units 2 is a telescopic bracket body, and the shape and volume of the bracket unit 2 can be adjusted by contraction and expansion. The bracket units 2 are open at both ends and are hollow inside.

[0039] The catheter 3 passes through the string-type stent 1. One end of the string-type stent 1 is fixed to the catheter 3, and the other end forms an operating end 9 and is movably connected to the catheter 3. When the operating end 9 is pushed or pulled back along the catheter 3, the stent unit 2 expands into a sphere or contracts into an olive shape.

[0040] The surface of the stent unit 2 is hollowed out so that the stent unit 2 can fully wrap the thrombus when it is extended into the thrombus and then swells into a sphere, and can stably carry the thrombus out of the blood vessel as the string stent 1 and catheter 3 move after shrinking into an olive shape.

[0041] The string-type stent 1 in this embodiment includes a plurality of stent units 2 connected in series, that is, each stent unit 2 is a subunit of a stent, and the string-type stent 1 is formed by connecting a plurality of subunits in series, and the number of the subunits is not fixed, and can be one, two, three, etc., and is not specific and unique, and the number can be adjusted according to the size of the thrombus. The stent unit 2 in this embodiment is a telescopic stent body, which can be retracted and bound to the surface of the catheter 3, similar to the state of the umbrella body against the umbrella pole after the umbrella is folded. The degree of contraction of the stent unit 2 is not fixed, and the overall degree of contraction can be larger, closer to the catheter 3, or the overall degree of contraction can be smaller, relatively away from the catheter 3. The catheter 3 in this embodiment passes through the string-type stent 1, and the stent unit 2 in the string-type stent 1 is hollow, with both ends open to allow the catheter 3 to pass through it. The surface of each stent unit 2 is hollow, so that the thrombus can be embedded therein and better wrapped.

[0042] When in use, medical personnel can use the catheter 3 to extend the string-type stent 1 wrapped on the catheter 3 into the catheter 3, and operate the string-type stent 1 to extend it into the thrombus, then expand it to wrap the thrombus, and then contract it to clamp the thrombus, so that when the string-type stent 1 is moved, the string-type stent 1 can carry the thrombus and move out of the blood vessel.

[0043] Based on the disclosure of the above embodiments, it can be known that the self-expanding thrombus stent has a simple overall structure and is easy to prepare. It can be achieved by only setting up a catheter 3 and a string-type stent 1, wherein the string-type stent 1 can move relative to the catheter 3 to expand into a spherical shape or shrink into an olive shape. The thrombus can be wrapped by operating the string-type stent 1, and can be carried out of the blood vessel together with the string-type stent 1 as it extends out of the blood vessel, thereby achieving the effect of clearing the thrombus quickly and effectively.

[0044] In specific implementation, a micro guidewire can be inserted into the catheter 3, and the micro guidewire can be extended into the blood vessel together with the catheter 3, and the micro guidewire can be used to complete drug injection by using a syringe at the front end (the operating side of medical staff). The specific usage method is not unique.

[0045] Furthermore, when the plurality of the series-connected stent units 2 in this embodiment are expanded to form spheres, at least some of the spheres have different inner diameters. For example, the inner diameters of some of the spheres may be different, including the inner diameters of the first sphere, the second sphere, and the third sphere. However, there may be multiple spheres with the same inner diameter, or the inner diameters of all the spheres may be different.

[0046] In one embodiment, the plurality of series-connected bracket units 2 are divided into three parts, each part includes one or more bracket units 2 with the same inner diameter, and the bracket units 2 belonging to different parts have different inner diameters. For example, each part may include a plurality of bracket units 2, the bracket units 2 in the same part have the same inner diameter, and the bracket units 2 in different parts have different inner diameters.

[0047] In this embodiment, in the direction of extending into the blood vessel, that is, from the operating side of the medical staff, the three parts are the first part, the second part and the third part. In the direction of the string-type stent 1 extending into the blood vessel, the inner diameters of the stent units 2 in the three parts gradually increase. That is, the inner diameter of the sphere formed when the stent unit 2 in the first part is expanded is smaller than the inner diameter of the sphere formed when the stent unit 2 in the second part is expanded, and the inner diameter of the sphere formed when the stent unit 2 in the second part is expanded is smaller than the inner diameter of the sphere formed when the stent unit 2 in the third part is expanded.

[0048] Specifically, in the embodiment, the direction in which the string-type stent 1 extends into the blood vessel is sequentially the first part, the second part and the third part, the inner diameter of the stent unit 2 of the first part has a value range of 1.5mm-2.5mm, the inner diameter of the stent unit 2 of the second part has a value range of 2.0mm-3.0mm, and the inner diameter of the stent unit 2 of the third part has a value range of 3.0mm-4.0mm. In this embodiment, the string-type stent 1 is usually used in blood vessels with an inner diameter of 1.5mm and above. For blood vessels with a diameter of less than 1.5mm, conservative drug thrombolysis is often used in the current medical field. However, if the process accuracy allows, the overall size of the string-type stent 1 of this embodiment can also be reduced to achieve application. The above-mentioned inner diameter has an intersection. When preparing the stent units 2 of different parts, the size of the inner diameter cannot be a value within the intersection area, and the inner diameters of the stent units 2 of different parts must be different.

[0049] The reason for adopting the above-mentioned setting mode is that, in the blood vessel, the thrombus is a small piece formed by the blood remaining in the peeling or repairing part of the inner surface of the blood vessel, which is affected by the variable fluid dependence, that is, the direct influence of the blood flow rate, and there are many factors that affect the blood flow rate, such as emotional excitement, high blood pressure, strenuous activities, etc., so the thrombus formation is extremely unstable in the early stage and the texture is relatively fragile. In order to be able to fully and stably wrap the thrombus after the string-type stent is expanded after passing through the thrombus, and then carry the thrombus out of the blood vessel, the string-type stent in this embodiment is designed as the above-mentioned coaxial concentric circle design concept in space to set a plurality of serial spherical stents, and the inner diameter size of each spherical stent is different, so that it can adapt to the irregular cross-section of the blood vessel due to the thrombus (the cross-section of the normal blood vessel is approximately circular), which is convenient for it to move, expand and shrink in the blood vessel, and at the same time, it can better apply different planes and multi-level wrapping forces to the thrombus, so as to achieve a better capture effect on the thrombus. Moreover, since the thrombus will be subjected to squeezing force when it is wrapped, the blood clot inside the thrombus will move and cause it to deform. Since the spherical stents in this embodiment have different inner diameters, there is at least one spherical stent of regular size that can adapt to the current shape and size of the thrombus, and can provide it with a stable and strong wrapping force to prevent it from slipping out of the stent, ensuring that it can be smoothly removed from the blood vessel to complete the cleaning of the thrombus.

[0050] In another embodiment, the string-type bracket 1 includes a plurality of axially arranged first ribs 4, one end on the same side of the plurality of first ribs 4 is connected to a first annular fixing ring 6, the first fixing ring is fixed on the catheter 3, the other ends on the same side of the plurality of first ribs 4 are cooperated and wound around the catheter 3 to form the operating end 9, the middle parts of the plurality of first ribs 4 are bound by a plurality of spaced second annular fixing rings 7 to form multiple sections, and the plurality of first ribs 4 between two adjacent second annular fixing rings 7 and the first annular fixing ring 6 and the adjacent second annular fixing ring 7 form the skeleton of the bracket unit 2.

[0051] That is, one end of the plurality of first ribs 4 is fixed on the side of the catheter 3 away from the staff, and the plurality of first ribs 4 are arranged at intervals or closely relative to the catheter 3, which is not determined in detail. The other ends of the plurality of first ribs 4 are wound on the catheter 3 to form a columnar body, which is coaxial with the catheter 3 and can move along the axis relative to the catheter 3, and the columnar body is the operating end 9, which may not be a columnar body, but may be other shapes, which is not determined in detail. Among them, one end of the plurality of first ribs 4 away from the operating end 9 is fixedly connected to the catheter 3 by the isomorphic first annular fixing ring 6, and the first ribs 4 from the first annular fixing ring 6 to the operating end 9 are bound by a plurality of second annular fixing rings 7, and a plurality of slots may be provided on the inner side of the second annular fixing ring 7, and a damping part or a stopper part, such as a curved protrusion, may be provided on the first rib 4, so that the second annular fixing ring 7 will be limited in a fixed position. Each first rib 4 is slidably connected to the second annular fixing ring 7 through each slot, that is, the first rib 4 can be bound and can slide relative to the second annular fixing ring 7, and then when the operating end 9 is axially slid, the first rib 4 can expand and move in a direction away from the catheter 3, or move and shrink in a direction close to the catheter 3. When multiple first ribs 4 expand, the second annular fixing ring 7 binds the multiple first ribs 4, and then forms a spherical or olive shape between two adjacent annular fixing rings.

[0052] Further, in this embodiment, in order to better wrap the plurality of first ribs 4 forming the skeleton, a plurality of elastic second ribs 5 are provided along the circumference of the bracket unit 2, the second ribs 5 are annular, the second ribs 5 are surrounded by wavy or serrated elastic members, and the plurality of second ribs 5 are arranged in parallel and at intervals. For the specific structure, please refer to Figure 1 As shown. The second rib 5 is elastic in the circumferential direction and can be enlarged or reduced. Each of the second ribs 5 is connected to the corresponding first rib 4. When the first rib 4 is operated to expand, the second rib 5 will also be propped up and enlarged under the action of the first rib 4 to form a ring with the size of the corresponding spherical cross section. Therefore, the bracket unit 2 is actually formed by a skeleton composed of multiple first ribs 4 and a mesh composed of multiple second ribs 5.

[0053] When the operating end 9 is pushed to expand the first rib 4, the first ribs 4 exert a pulling force on the second ribs 5, and the second ribs 5 are elastically pulled up by the first ribs 4, so that the whole is propped up, and the bracket unit 2 is spherical. When the operating end 9 is pulled back to tighten the first rib 4 and lean against the catheter 3, the second ribs 5 are compressed and contracted by the radial restraining force of the first rib 4, that is, the squeezing force, so that the bracket unit 2 is olive-shaped.

[0054] Furthermore, in practical applications, the preparation materials involved in the string-type stent 1 in this embodiment are all Nitinol alloys. Of course, other materials can also be used, depending on the actual situation, and are not limited here.

[0055] In another embodiment, if Figure 3 As shown, the self-expanding thrombus stent further includes an outer catheter 8, and the string-type stent 1 is inserted into the outer catheter 8, and when the outer catheter 8 is extended, each of the stent units 2 expands into a spherical shape, and when the outer catheter 8 is retracted, each of the stent units 2 shrinks into an olive shape. The string-type stent 1 in this embodiment is contracted by the outer catheter 8 and is bound to form an olive shape. The outer catheter 8 applies a squeezing force to the string-type stent 1 in the circumferential direction so that the string-type stent 1 is contracted as a whole, and when the string-type stent 1 is driven to extend out of the outer catheter 8 through the catheter 3, the string-type stent 1 can automatically expand without the operator operating the operating end 9.

[0056] In addition, in order to further prevent the string-type stent 1 from slipping off the catheter 3, a fixing cap is provided on the top of the catheter 3 in this embodiment to stop the string-type stent 1. That is, a fixing cap is provided at the end of the catheter 3 to stop the string-type stent 1 from slipping off. When the fixing cap is applied, the first annular fixing ring 6 can be non-fixedly connected to the catheter 3 or fixedly connected to the catheter 3, and the fixing cap is provided at the same time, or no fixing cap is provided.

[0057] In another embodiment, in order to facilitate the outer catheter 8 to extend into the blood vessel, a hydrophilic layer is specially provided on the outside of the outer catheter 8 and a lubricating layer is provided on the inside of the outer catheter 8 to facilitate the string-type stent 1 to extend into and out of the outer catheter 8.

[0058] The above embodiments are only exemplary embodiments of the present invention and are not intended to limit the present invention. The protection scope of the present invention is defined by the claims. Those skilled in the art may make various modifications or equivalent substitutions to the present invention within the essence and protection scope of the present invention, and such modifications or equivalent substitutions shall also be deemed to fall within the protection scope of the present invention.

Claims

1. A self-expanding thrombus stent, characterized in that: include: A series-type bracket, comprising a plurality of bracket units connected in series, each of which is a telescopic bracket body, which can adjust the shape and volume of the bracket unit by contraction and expansion, and the bracket unit is open at both ends and hollow inside; A catheter passes through the string-type stent, one end of the string-type stent is fixed to the catheter, and the other end forms an operating end and is movably connected to the catheter. When the operating end is pushed or pulled back along the catheter, the stent unit swells to form a sphere, or contracts to form an olive shape; The surface of the stent unit is hollowed out, so that the stent unit can fully wrap the thrombus when it is extended into the thrombus and then swells into a sphere, and can stably carry the thrombus out of the blood vessel as the string-type stent and catheter move after shrinking into an olive shape; When the plurality of stent units connected in series are expanded to form a sphere, at least some of the spheres have different inner diameters. The plurality of stent units connected in series are divided into three parts, each part includes one or more stent units with the same inner diameter, and the inner diameters of the stent units belonging to different parts are different. In the direction in which the string-type stent extends into the blood vessel, the inner diameters of the stent units in the three parts gradually increase. The string-type stent comprises a plurality of first ribs arranged axially, one end of the first ribs on the same side is connected to a first annular fixing ring, the first annular fixing ring is fixed on the catheter, the other ends of the first ribs on the same side are wound around the catheter to form the operating end, a plurality of second annular fixing rings for restraining the first ribs are arranged at intervals in the middle of the plurality of first ribs, and the plurality of first ribs between two adjacent second annular fixing rings and the first annular fixing ring and the adjacent second annular fixing ring form the skeleton of the stent unit; A plurality of elastic and annular second ribs are provided on the plurality of first ribs forming the skeleton. When the operating end is pushed to expand the first ribs, the plurality of second ribs are elastically propped up without the restraining effect of the first ribs, thereby making the bracket unit spherical. When the operating end is pulled back to tighten the first ribs and lean against the catheter, the plurality of second ribs are compressed and contracted by the radial restraining force of the first ribs, thereby making the bracket unit olive-shaped.

2. The self-expanding thrombus stent according to claim 1, characterized in that: In the direction in which the string-type stent extends into the blood vessel, there are sequentially a first part, a second part and a third part. The inner diameter of the stent unit of the first part ranges from 1.5mm to 2.5mm, the inner diameter of the stent unit of the second part ranges from 2.0mm to 3.0mm, and the inner diameter of the stent unit of the third part ranges from 3.0mm to 4.0mm.

3. The self-expanding thrombus stent according to claim 1, characterized in that: The second ribs are surrounded by wave-shaped or sawtooth-shaped elastic members, and a plurality of the second ribs are arranged in parallel and at intervals; The preparation materials involved in the string-type stent are all Nitinol alloy.

4. The self-expanding thrombus stent according to claim 1, characterized in that: It also includes an outer catheter, wherein the string-type stent is inserted into the outer catheter, and each of the stent units is expanded to be a sphere when the outer catheter is extended, and each of the stent units is contracted to be an olive shape when the outer catheter is retracted; The top cover of the conduit is provided with a fixing cap for stopping the string-type bracket.

5. The self-expanding thrombus stent according to claim 4, characterized in that: A hydrophilic layer is disposed on the outside of the outer conduit, and a lubricating layer is disposed on the inside of the outer conduit.

Images