Lumen-adjustable stent

Abstract

The present application relates to a lumen-adjustable stent. An adjusting member of the stent comprises a first end, a second end, and an intermediate segment connecting the first end to the second end. An accessory is connected to a body of the stent, extends naturally relative to the body, and forms a channel allowing the adjusting member to pass through. The stent comprises an initial state and an adjustment state. In the initial state, the first end and the second end are close to the two ends of the channel, the intermediate segment passes through the channel, the natural extension length of the intermediate segment is less than the natural extension length of the accessory between the first end and the second end, and by limiting the natural extension of the accessory forming the channel, the body is circumferentially compressed, so as to adjust the sectional dimension of the lumen. In the adjustment state, the restriction of at least one of the first end and the second end on the accessory is relieved, such that the circumferential compression of the body is at least partially restored to allow the adjustment of the sectional dimension of the lumen again.

Description

Lumen-adjustable stent

[0001] Citation of Related Applications

[0002] This application claims all rights and interests in the Chinese invention patent application with application number 202410182381.3 and invention name “Lumen-Adjustable Stent” filed with the State Intellectual Property Office of the People’s Republic of China on February 18, 2024, and incorporates its entire contents into this application by reference.

[0003] field

[0004] The present application relates to the field of medical devices, and in particular to a stent with adjustable lumen.

[0005] background

[0006] Stents are a commonly used medical device in the medical field and can be widely used in the heart, blood vessels, liver, etc. Existing stents are often metal stents sutured, wrapped or coated with thin film materials, wherein the metal stents provide radial support and anchor the thin film material. Currently, almost all covered stents act as artificial blood vessels to dredge and divert blood. However, the radial dimensions of existing covered stents are unique, although there are multiple specifications. Once the specifications are determined, it is difficult to readjust the stent after implantation into the human body.

[0007] For example, stents used in transjugular intrahepatic portocaval shunts (TIPS) are generally divided into two categories: balloon-expandable stents and self-expanding stents. After implantation, balloon-expandable stents provide poor support for the stent itself, increasing the probability of subsequent stent lumen collapse. Furthermore, due to the constraints of extraluminal tissue, subsequent balloon expansion is ineffective, making diameter adjustment difficult. Self-expanding stents are also difficult to adjust in diameter after implantation.

[0008] Currently, for TIPS, after a stent is implanted for a period of time in clinical practice, at least one pressure measurement is required for at least 24 hours to determine whether there is a need to adjust the stent. When the portal vein pressure decreases but has not yet reached the reference range, the diameter of the stent needs to be increased to achieve the effect of reducing the portal vein pressure again. This requires that the diameter of the stent can be adjusted after implantation. In related technologies, a layer of deformable and stretchable material is usually added to the outer wall of the stent to compress the stent. After the stent is implanted, the deformable and stretchable material is torn and deformed by balloon expansion, thereby reducing the amount of constraint on the stent diameter and achieving the effect of adjusting the stent diameter.

[0009] Overview

[0010] The present application provides a stent with adjustable lumen, comprising a main body and an adjustment assembly. The main body comprises a skeleton and a membrane covering at least a portion of the skeleton, and the main body encloses a lumen. The adjustment assembly comprises an adjustment member and an attachment; the adjustment member comprises a first end, a second end, and an intermediate section connecting the first and second ends; the attachment is connected to the main body and naturally extends and expands relative to the main body, forming a channel for the adjustment member to pass through. The stent comprises an initial state and an adjustment state. In the initial state, the first and second ends are respectively near the two ends of the channel, and the intermediate section is disposed in the channel. The natural extension length of the intermediate section is less than the natural extension length of the attachment between the first and second ends. By restricting the natural extension and expansion of the attachment forming the channel, the cross-sectional size of the lumen is adjusted by at least partially circumferentially compressing the main body. In the adjustment state, at least one of the first and second ends releases the restriction on the attachment, so that the circumferential compression of the main body is at least partially restored, so as to adjust the cross-sectional size of the lumen again.

[0011] BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0013] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0014] FIG1 is a schematic structural diagram of a stent with adjustable lumen according to an embodiment of the present application in a naturally deployed state;

[0015] FIG2 is a schematic structural diagram of the bracket in FIG1 in an initial state;

[0016] FIG3 is a schematic diagram of the structure of the attachment and the frame in any example embodiment;

[0017] FIG4 is a schematic diagram of the structure at the end of an accessory in any example embodiment;

[0018] FIG5 a is a schematic structural diagram of an adjusting member in any exemplary embodiment;

[0019] 5b and 5c are schematic diagrams showing the formation of the first end or the second end of the adjusting member in FIG. 5a ;

[0020] FIG6 is a schematic diagram of the structure of the attachment and the limiting member in any example embodiment;

[0021] FIG7 is a schematic diagram of the structure of an accessory in any example embodiment;

[0022] FIG8 is a schematic diagram of a stent in a naturally expanded state according to an embodiment;

[0023] FIG9 is a schematic diagram of the bracket in FIG8 in an initial state;

[0024] FIG10 is a schematic diagram of the bracket in FIG8 in an adjusted state;

[0025] FIG11 is a schematic diagram of a portion of the bracket in FIG8 in an initial state.

[0026] Details

[0027] To make the purpose, technical solutions, and advantages of the embodiments of this application more clear, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0028] As shown in Figures 1 and 2, the present application relates to a stent 1 with adjustable lumen, comprising a main body 10 and an adjustment assembly 20. The main body 10 includes a skeleton 110 and a coating 120 covering at least a portion of the skeleton 110, and the main body 10 encloses a lumen 100. The adjustment assembly 20 includes an adjustment member 210 and an attachment 220; the adjustment member 210 includes a first end 211, a second end 212, and an intermediate section 213 connecting the first and second ends 211 and 212; the attachment 220 is connected to the main body 10 and naturally extends relative to the main body 10, forming a channel 200 for the adjustment member 210 to pass through. The stent 1 includes an initial state and an adjustment state. In the initial state, the first end 211 and the second end 212 are respectively near the two ends of the channel 200, and the middle section 213 is arranged in the channel 200. The natural extension length of the middle section 213 is less than the natural extension length of the attachment 220 between the first end 211 and the second end 212. By limiting the natural extension and expansion of the attachment 220 that forms the channel 200, the cross-sectional size of the tubular cavity 100 is adjusted by compressing the main body 10 in at least a part of the circumferential direction B; in the adjustment state, at least one of the first end 211 and the second end 212 releases the restriction on the attachment 220, so that the circumferential B compression of the main body 10 is at least partially restored to adjust the cross-sectional size of the tubular cavity 100 again.

[0029] The stent 1 with adjustable lumen (hereinafter referred to as stent 1) of the present application changes the extended deployment length of the attachment 220 through the adjusting member 210, thereby changing the circumferential B shape of the main body 10 connected to the attachment 220, so as to adjust the radial size of the lumen 100 formed by the main body 10, and finally achieve the effect of adjusting the diameter of the stent 1. With this adjustment method, the diameter of the stent 1 can be adjusted by simply changing the restriction or constraint of the adjusting member 210 relative to the attachment 220. Therefore, the integrity of the main body 10 of the stent 1 during the diameter adjustment of the lumen 100 can be ensured, and the strength of the stent 1 will not be affected, such as causing uneven strength distribution of the stent 1, thereby preventing tissue from penetrating the surface of the stent 1 and growing into the lumen 100 of the stent 1 after the stent 1 is implanted, or excessive tissue growth from squeezing the lumen 100 of the stent 1, thereby improving the safety and reliability of the stent 1 after surgery.

[0030] Specifically, referring to FIG1 , the stent 1 is in a naturally deployed state. In this naturally deployed state, the first end 211 and the second end 212 do not restrict the appendage 220, or the restriction on the appendage 220 has been completely released. The appendage 220 naturally extends and expands, and its naturally extended length is L0. It is understood that in order to achieve the effect of the appendage 220 changing the radial compression state of the body 10 of the stent 1, the appendage 220 can be prevented from naturally extending and expanding in a direction parallel to the axial direction A, ensuring that it naturally extends and expands at least partially or entirely in the circumferential direction B of the body 10. In some embodiments, the appendage 220 can be connected to the body 10 on its outer circumferential surface and extend along the circumferential direction B, which can be considered to be the outer circumferential direction of the body 10. The extension of the appendage 220 along the circumferential direction B can be understood as extending directly in the circumferential direction B, or it can be understood as its projection on a cross section perpendicular to the axial direction A extending along the circumferential direction B. Therefore, when the attachment 220 is in the naturally extended and expanded state, the main body 10 at the connection of the attachment 220 is not compressed or restricted, and the diameter of the lumen 100 is the naturally expanded size D0.

[0031] 2 , the bracket 1 also has an initial state. In this initial state, the first end 211 and the second end 212 of the adjusting member 210 are respectively located near the ends of the channel 200, and the middle section 213 is disposed within the channel 200. For example, the first end 211 and the second end 212 may be larger than the internal dimensions of the channel 200. When the first end 211 and / or the second end 212 are located near the ends outside the channel 200 or near the ends inside the channel 200, due to their size, the first end 211 and the second end 212 will be stuck at the ends of the channel 200 formed by the attachment 220, causing the adjusting member 210 to be temporarily stuck within the attachment 220. The natural extension length of the middle section 213 is set to be smaller than the natural extension length of the attachment 220 between the first end 211 and the second end 212. Because the first end 211 and the second end 212 of the adjusting member 210 have been stuck, the length of the attachment 220 between the first end 211 and the second end 212 will be limited or constrained to be close to the length of the middle section 213, limiting the natural extension and expansion of the attachment 220 that forms the channel 200, so that the extension length of the attachment 220 is controlled and adjusted by the length of the middle section 213. Therefore, the extension length of the attachment 220 is compressed from the natural extension length L0 to L1, L1<L0. The compression of the attachment 220 causes the main body 10 connected to the attachment 220 to be compressed at the same time, thereby changing the diameter of the main body 10 at the connection of the attachment 220, from the naturally expanded D0 to D1, D1<D0, thereby realizing the adjustment of the cross-sectional size of the tubular cavity 100.

[0032] The stent 1 also has an adjustment state. In the adjustment state, at least one of the first end 211 and the second end 212 releases the restriction on the accessory 220, so that the circumferential B compression of the main body 10 is at least partially restored. For example, after the first end 211 releases the restriction on the accessory 220, the accessory 220 on the side of the first end 211 is released from the compressed or constrained state and can gradually restore its length. At this time, the accessory 220 has an adjusted extension length L2, L1<L2<L0, so that the circumferential B compression of the main body 10 at the connection of the accessory 220 is also gradually released accordingly, and its adjusted diameter D2 satisfies D1<D2<D0, so as to adjust the cross-sectional size of the lumen 100 again.

[0033] Based on this, it can be seen that in the stent 1 of the present application, by providing a constrained cooperation between the adjusting member 210 and the attachment 220, the circumferential extension length of the attachment 220 is changed, thereby changing the circumferential compression profile of the main body 10 at the attachment 220, thereby adjusting the diameter of the stent 1. This adjustment does not affect the structure of the main body 10 itself, and therefore does not affect the strength of the stent 1 after implantation, ensuring the safe implantation of the stent 1. It also prevents tissue growth in vulnerable areas of the stent 1, thereby preventing such tissue growth from squeezing the lumen 100 of the stent 1 and causing stenosis or obstruction. Furthermore, this adjustment is controllable, allowing for the controlled release of at least one of the first end 211 and the second end 212 from the constraint or restriction, and for the gradual release of the first end 211 and / or the second end 212 from the channel 200 of the attachment 220. Compared to related art methods that typically achieve diameter adjustment of the stent 1 only by tearing the deformable and ductile material attached to the outer surface of the stent 1, the stent 1 of the present application offers greater adjustment precision and a wider range of adjustable dimensions within its diameter adjustment range.

[0034] Specifically, the main body 10 of the stent 1 of the present application is a tubular structure with two ends open and the middle closed, and the tubular cavity 100 formed constitutes a blood flow channel for blood circulation. Its skeleton 110 includes at least one annular wave ring. When there are multiple annular wave rings, the multiple annular wave rings are arranged at intervals along the axial direction. The "annular" of the annular wave ring can be a closed ring, or an open ring extending in an axial spiral. The multiple annular wave rings can be connected, such as flexibly connected or rigidly connected, or not connected, which will not be repeated here. The annular wave ring also includes a plurality of alternating and staggered peaks 111 and troughs 112, and a plurality of connecting rods 113 connecting adjacent peaks 111 and troughs 112. The waveform in the annular wave ring can be a sine wave, a square wave, a triangular wave, etc., which will not be listed here one by one. This waveform structure of the annular wave ring is easy to compress and expand, which is beneficial to improving the ductility of the overall structure of the skeleton 110.

[0035] The skeleton 110 can be made of a material with good biocompatibility and good elasticity, such as stainless steel, nickel-titanium alloy or cobalt-chromium alloy, iron-based materials, etc. In the actual production process, the skeleton 110 is formed by braiding nickel-titanium wire or cutting and shaping nickel-titanium tube. Of course, the skeleton 110 can also be braided or cut and shaped by stainless steel wire. By selecting the material of the skeleton 110, a self-expanding skeleton 110 can be formed, and an axially expandable skeleton 110 can also be formed. It should be known that the above-mentioned skeleton 110 is only used as an example and is not a limitation of this application. Ordinary technicians in this field can select a suitable skeleton 110 according to the usage scenario and actual needs, which will not be repeated here.

[0036] In certain embodiments, the skeleton 110 may have a self-expansion force, meaning that the skeleton 110 tends to return to its naturally expanded configuration when subjected to an external restraining force. When the external restraining force applied to the skeleton 110 is greater than the skeleton 110's current self-expansion force, the skeleton 110 is continuously compressed at the location subject to the external restraining force. When the skeleton 110 is continuously compressed until the self-expansion force equals the external restraining force, the skeleton 110 remains compressed. When the external restraining force applied to the skeleton 110 decreases, the skeleton 110 gradually expands under the action of its self-expansion force. When the external restraining force disappears, the skeleton 110 returns to its naturally expanded configuration.

[0037] The membrane 120 can be made of a thin film material with good biocompatibility, such as polyethylene terephthalate (PET) or expanded polytetrafluoroethylene (e-PTFE). The membrane 120 and the skeleton 110 form a tubular structure with open ends and a closed center, forming a blood flow channel for blood or other fluids. The lumen 100 of the body 10 forms the blood flow channel, and the cross-section of the lumen 100 can be circular, elliptical, or other shapes.

[0038] The attachment 220 of the adjustment assembly 20 is connected to the main body 10 on its outer circumferential surface and forms a passage 200 through which the adjustment member 210 passes. At least a portion of the attachment 220 extends along the circumferential direction B on the outer circumferential surface of the main body 10. This can be understood as extending directly in the circumferential direction B, or as extending parallel to the axial direction A, with its projection on a cross-section perpendicular to the axial direction A extending along the circumferential direction B. For example, the attachment 220 can be strip-shaped, with its two long sides connected to the main body 10 to form the passage 200, and its two short sides forming the two ends of the passage 200. Of course, in addition to the strip-shaped square, any other shape is possible, as long as at least a portion of the outer circumferential surface of the main body 10 extends along the circumferential direction B. These shapes are not listed here. Furthermore, the two ends of the passage 200 can be closed relative to the main body 10 or open relative to the main body 10, and any combination of open and closed states is possible.

[0039] It can be understood that the attachment 220 constrains the body 10 in the circumferential direction B, which results in a simultaneous reduction in both the circumferential length and radial dimension of the body 10. That is, the attachment 220 constraining the body 10 in the circumferential direction B is equivalent to constraining the body 10 radially. Similarly, when the attachment 220's constraint on the body 10 in the circumferential direction B disappears, the constraint is equivalent to the disappearance of the attachment 220's constraint on the body 10 radially. In other words, after the attachment 220 constrains the body 10 in the circumferential direction B, the radial dimension of the body 10 also decreases. Therefore, the attachment 220 in the present application constrains the body 10 in the circumferential direction B, thereby achieving the effect of constraining the body 10 radially.

[0040] The attachment 220 can be made of materials with good biocompatibility and deformability under stress, such as flexible materials, stainless steel, platinum-iridium alloys, iron-based materials, gold, etc. Flexible materials are preferred, such as PTFE, PET, or PP. In different usage scenarios, materials with different elongations can be used. For example, a material with a lower elongation can be used to increase the restraint force on the coating 120 and the skeleton 110 in the circumferential direction B, thereby enhancing the ability of the stent 1 to maintain its radial shape. Alternatively, a material with a higher elongation can be used to reduce the restraint force on the coating 120 and the skeleton 110 in the circumferential direction B. In some embodiments, the attachment 220 can be made of the same material as the coating 120 to ensure compression consistency.

[0041] Referring to Figure 3, the axial distance between the crest 111 and the trough 112 in the annular wave ring can be defined as the wave height H1, and the area where H1 is located is the elastic area of ​​the annular wave ring. At the same time, the axial length of the annular wave ring constrained by the attachment 220 is defined as H2, wherein H2 is greater than or equal to half of H1, that is, H2 ≥ 1 / 2H1. At this time, the constraint area of ​​the annular wave ring by the attachment 220 is the elastic area, that is, the attachment 220 can fully constrain the elastic area to constrain the main body 10 in the circumferential direction B, thereby reducing the diameter of the main body 10. Therefore, the elastic area on the annular wave ring can be fully constrained, which can prevent the unstable connection of the attachment 220 caused by the unevenness of the two sides of the annular wave ring (one side is high and the other side is low), which is conducive to improving the constraint effect of the attachment 220 on the main body 10.

[0042] The selection of different accessories 220 determines the constraint restriction method between the adjusting member 210 and the accessory 220 and the corresponding method of releasing the constraint restriction, that is, adjusting the size of the channel 200 can realize the constraint restriction of the adjusting member 210, and the channel 200 is opened or increased in size to realize the release of the constraint restriction. For example, when the accessory 220 is made of materials such as ePTFE membrane or FEP, the channel 200 can be expanded by the principle of hot pressing and separating the two layers of membrane. When the accessory 220 is made of elastic materials with variable area (such as silicone, etc.), the channel 200 can be expanded by deforming the accessory 220. When the accessory 220 is made of materials such as PET and connected by suturing, the channel 200 can be expanded by rupturing the accessory 220 or failing the suture position of the accessory 220. Among them, the failure of the suture position can be caused by the suture line breaking, the elastic stretching of the suture line, the suture knot falling off, the suture knot loosening, and the suture knot deformation. When the attachment 220 is made of a material that can be absorbed by the human body, the human body absorbs and degrades the attachment 220 at the connection. After a period of time, the attachment 220 gradually disappears, thereby releasing the constraint on the adjustment member 210. The above multiple channel opening methods are only examples and are not limitations of this application. Based on the teachings of this application, other methods can also be used to open the channel 200, which will not be repeated here.

[0043] Furthermore, referring to FIG4 , the cross-sectional area of ​​the portion of the appendage 220 near the end 221 is larger than the cross-sectional area of ​​the remaining portion (or the cross-sectional area of ​​the portion of the appendage 220 near the end 221 gradually increases), and the end 221 may be an open structure to facilitate the first end 211 or the second end 212 of the adjusting member 210 to enter the channel 200. Under the action of an external force, such as when the balloon is expanded, the adjusting member 210 can precisely expand the connection between the appendage 220 and the covering 120, allowing the adjusting member 210 to move within the channel 200 toward the side away from the end 221, thereby releasing the radial constraint of the appendage 220 on the body 10.

[0044] The stent 1 may include at least two relatively staggered attachments 220. The at least two attachments 220 may be spaced apart along the circumference B of the main body 10. In this case, the at least two attachments 220 can provide multiple stages of circumferential constraint on the main body 10, as needed, thereby enhancing the constraint effect. Furthermore, the at least two attachments 220 may be spaced apart along the axial direction of the main body 10. In this case, the at least two attachments 220 can provide multiple stages of axial constraint on the main body 10, as needed, further enhancing the constraint effect. In certain embodiments, when the attachments 220 are sufficiently long, they can constrain the main body 10 in the circumferential direction B. This approach provides more uniform constraint on the main body 10 in the circumferential direction B, facilitating subsequent adjustment of the diameter of the main body 10. Alternatively, a single attachment 220 can wrap around the main body 10 at least once in the circumferential direction B, thereby constraining the main body 10 in the circumferential direction B for one or more complete turns. This approach provides a more secure constraint on the main body 10 and reduces the risk of constraint failure.

[0045] Referring to Figure 5a, in the bracket 1 of the present application, the middle section 213 of the adjustment member 210 is a flexible cable; at least one of the first end 211 and the second end 212 is an elastically deformable body or a plastically deformable body, and is connected to the middle section 213 on opposite sides of the middle section 213. For example, at least one of the first end 211 and the second end 212 can be spherical, olive-shaped, conical, or a special shape, or can be braided and shaped to form the final shape.

[0046] In certain embodiments, referring to Figures 5b and 5c , the middle section 213 of the adjusting member 210 is a cable; at least one of the first end 211 and the second end 212 is a cable made of a mixed braid of PET thread 2101 and PTFE thread 2102, formed by knotting to form an elastically deformable body 2100. Therefore, not only can the material selection of the accessory 220 be used to open the channel 200 of the accessory 220, thereby removing the restriction, but the restriction can also be removed by elastic deformation of at least one of the first end 211 and the second end 212, or by the simultaneous action of the accessory 220 and the adjusting member 210.

[0047] In some embodiments, the first end 211 is larger than the end of the adjacent channel 200 so that the first end 211 is engaged with the end to restrict the natural extension and deployment of the appendage 220 on that side. The second end 212 is larger than the end of the adjacent channel 200 so that the second end 212 is engaged with the end to restrict the natural extension and deployment of the appendage 220 on that side. Under the action of an external force, such as balloon inflation, the appendage 220 opens the channel 200 by at least one of the above-mentioned methods, such as elastic or plastic deformation of the appendage 220, allowing the first end 211 and / or the second end 212 to enter the channel 200 and release the constraint on the appendage 220; or the first end 211 and / or the second end 212 enter the channel 200 through self-deformation, elastic deformation, or plastic deformation, thereby releasing the constraint on the appendage 220; or the appendage 220 and the first end 211 and / or the second end 212 of the adjusting member 210 work together to release the constraint.

[0048] 6 , in other embodiments of the present application, the main body 10 further includes a limit member 130, which is a structure with one end larger than the other, such as a frustum-shaped structure, a teardrop-shaped structure, a spherical structure, or a ring-shaped structure. A portion of the limit member 130 is inserted into the end of the accessory 220, and the inner cavity of the limit member 130 is connected to the channel 200; wherein, the bottom side with a smaller diameter in the limit member 130 extends into the channel 200 from the end of the channel 200, and the bottom end side with a larger diameter in the limit member 130 is outside the channel 200 and is stuck at the end of the channel 200; the adjusting member 210 passes through the channel 200 from the limit member 130, and is stuck in the inner cavity of the limit member 130 by at least one of the first end 211 and the second end 212 to limit the natural extension and deployment of the accessory 220 on this side. The use of the limiting member 130 can effectively ensure that the first end 211 or the second end 212 is released from the constraint and enters the channel 200 under the action of an external force, thereby improving the effectiveness and accuracy of the diameter adjustment.

[0049] In some embodiments, the limiting member 130 is a mesh that covers the end of the channel 200. The mesh includes at least one mesh hole, the natural aperture of which is smaller than the size of both the first end 211 and the second end 212. At least one of the first end 211 and the second end 212 is engaged with the mesh hole of the limiting member 130 to limit the natural extension and deployment of the accessory 220 on that side. Under the action of an external force, at least one of the first end 211 and the second end 212 deforms, such as elastically or plastically, to break through the mesh hole and enter the channel 200, thereby releasing the constraint on the accessory 220. Alternatively, under the action of an external force, the mesh wire forming the mesh in the limiting member 130 deforms or breaks, allowing the first end 211 or the second end 212 to break through the mesh hole and enter the channel 200, thereby releasing the constraint on the accessory 220. Alternatively, the mesh wire and the first end 211 or the second end 212 act together. The use of the limiting member 130 can effectively ensure that the first end 211 or the second end 212 is released from the constraint and enters the channel 200 under the action of external force, thereby improving the effectiveness of diameter adjustment.

[0050] It can be seen from the above examples that when the first end 211 or the second end 212 is released from the constraint restriction relative to the accessory 220, at least one of the first end 211 and the second end 212 can continue to pass through the channel 200 under the action of the external expansion force to further release the restriction on the accessory 220 until the accessory 220 returns to its naturally extended length, thereby realizing precise adjustment of the diameter of the bracket 1 within a certain range, rather than adjusting the diameter of the bracket 1 at one time.

[0051] Referring to Figure 7, in an example embodiment of the present application, the attachment 220 may extend on the main body to form a bending constraint portion 222. The bending constraint portion 222 is connected to the coating 120. The axial distance between the wave crest 111 and the wave trough 112 in the annular wave ring is defined as the wave height H1, the region where H1 is located is the elastic region of the annular wave ring, the wavelength of the annular wave ring is H4, and the length of the bending constraint portion 222 in the circumferential direction B is H3. At this time, H3 < 1 / 2H4. The bending constraint portion 222 can increase the friction between the attachment 220 and the main body 10, reduce the influence of external friction on the stent 1 during transportation, assembly, and release, and help avoid the generation of a large separation force at the connection position between the attachment 220 and the coating 120, which may cause the attachment 220 to fail prematurely.

[0052] It is also understandable that there may be more than one bend constraint portion 222. Providing multiple bend constraint portions 222 can further enhance the connection strength between the accessory 220 and the body 10, thereby preventing the accessory 220 from failing prematurely.

[0053] Referring to Figures 8 to 15 , in one embodiment of the present application, an attachment 220 is spirally wound multiple times around the outer circumferential surface of the main body 10, extending and covering multiple turns in the circumferential direction B. The dashed line in the figure illustrates a section of the attachment, thereby uniformly compressing the main body 10 in the circumferential direction B over a certain axial length. A frustum-shaped stopper 130 is provided at the end of the attachment 220. The first and second ends 211, 212 of the adjusting member 210 are elastically deformable bodies formed by knotting a mixed braid of PET and PTFE wires. The middle section 213 of the adjusting member 210 is inserted into the channel 200 formed by the attachment 220. The stopper 130 at the end of the attachment 220 restricts the first end 211 or the second end 212 from entering the channel 200, thereby constraining the adjusting member 210 on the attachment 220.

[0054] 8 and 9 , the stent 1 is in a naturally expanded state, and its diameter is D0.

[0055] 10 and 11 , the stent 1 is in an initial state, and the attachment 220 is constrained by the first end 211 and the second end 212 , thereby radially compressing the body. At this time, the diameter of the stent 1 is D1 .

[0056] Referring to Figures 12 and 13, under the action of external force, such as balloon expansion, the first end 211 or the second end 212 undergoes elastic deformation and squeezes into the channel 200, thereby at least partially releasing the constraint on the attachment 220, and then at least partially releasing the constraint on the main body 10. The stent is in an adjusted state, and its diameter is D2, D1<D2<D0. Because the original size of the first end 211 or the second end 212 is larger than the size within the channel 200, even if the first end 211 or the second end 212 penetrates the channel 200, it may become stuck in the channel 200. If further external force is applied, such as continued balloon expansion, the first end 211 or the second end 212 may further deform, and the appendage 220 may also deform, tear, or expand. For example, the deformation may increase, or the appendage 220 may tear and separate relative to the main body 10, or the appendage 220 may expand relative to the main body 10, allowing the first end 211 or the second end 212 to continue to move in the channel 200, thereby further releasing the constraints on the appendage 220 and ultimately achieving continuous and gradual adjustment of the diameter of the main body 10. It should be noted that during the above-mentioned deformation, tearing, or expansion of the appendage 220, the structure of the main body 10 remains unchanged.

[0057] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or device comprising the element.

[0058] The foregoing is merely a detailed description of the present application to enable those skilled in the art to understand or implement the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application is not limited to the embodiments shown herein, but is intended to conform to the widest scope consistent with the principles and novel features of the present application.

Claims

1. A stent with adjustable lumen, comprising: A body, comprising a skeleton and a membrane covering at least a portion of the skeleton, wherein the body encloses a tubular cavity; as well as an adjustment assembly comprising an adjustment member and an accessory; wherein the adjustment member comprises a first end, a second end, and a middle section connecting the first end and the second end; the accessory is connected to the body and naturally extends relative to the body to form a passage for the adjustment member to pass through; In which, the stent includes an initial state and an adjustment state. In the initial state, the first end and the second end are respectively near the two ends of the channel, the middle section is arranged in the channel, and the natural extension length of the middle section is less than the natural extension length of the attachment between the first end and the second end. By limiting the natural extension and expansion of the attachment forming the channel, the cross-sectional size of the lumen is adjusted by at least partially compressing the body circumferentially; in the adjustment state, at least one of the first end and the second end releases the restriction on the attachment, so that the circumferential compression of the body is at least partially restored to adjust the cross-sectional size of the lumen again.

2. The stent with adjustable lumen according to claim 1, wherein: The bracket further includes a natural expansion state, in which the first end and the second end both release the restriction on the accessory, and the accessory naturally extends and expands.

3. The stent with adjustable lumen according to claim 1 or 2, wherein: The attachment is in a strip shape, and its two long sides are respectively connected to the main body to form the channel; and its two short sides respectively form the two ends of the channel.

4. The lumen-adjustable stent according to any one of claims 1 to 3, wherein: The middle section of the adjusting member is a flexible cable; at least one of the first end and the second end is an elastic deformable body or a plastic deformable body, and is respectively connected to the middle section at opposite sides of the middle section.

5. The lumen-adjustable stent according to any one of claims 1 to 4, wherein: The middle section of the adjusting member is a cable; at least one of the first end and the second end is an elastic deformable body formed by knotting a cable made by mixing PET wire and PTFE wire.

6. The lumen-adjustable stent according to any one of claims 1 to 5, wherein: The first end is larger than the end of the adjacent channel so that the first end is clamped at the end to limit the natural extension and deployment of the accessory; the second end is larger than the end of the adjacent channel so that the second end is clamped at the end to limit the natural extension and deployment of the accessory.

7. The stent with adjustable lumen according to any one of claims 1 to 6, wherein: The main body also includes a limiter, which is a frustum-shaped structure, with a portion of the limiter inserted into the end of the accessory, and an inner cavity of the limiter communicating with the channel; wherein, a bottom side with a smaller diameter in the limiter extends into the channel from the end of the channel, and a bottom end side with a larger diameter in the limiter is outside the channel and stuck at the end of the channel; the adjusting member passes through the limiter into the channel, and limits the natural extension and deployment of the accessory by at least one of the first end and the second end being stuck in the inner cavity of the limiter.

8. The lumen-adjustable stent according to any one of claims 1 to 7, wherein: The main body also includes a limiting member, which is a mesh body and covers the end of the channel; the mesh body includes at least one mesh hole, and the natural pore size of the mesh hole is smaller than the size of the first end and the second end at the same time. The natural extension and deployment of the accessory is limited by at least one of the first end and the second end being stuck in the mesh hole of the limiting member.

9. The stent with adjustable lumen according to any one of claims 1 to 8, wherein: When an external expansion force is applied to the body within the lumen, at least one of the first end and the second end enters the channel by tearing the attachment to release the restriction on the attachment; or at least one of the first end and the second end enters the channel by elastic deformation of itself and / or the attachment to release the restriction on the attachment; or at least one of the first end and the second end enters the channel by plastic deformation of itself and / or the attachment to release the restriction on the attachment.

10. The stent with adjustable lumen according to claim 9, wherein: At least one of the first end and the second end travels through the channel under the action of the external expansion force to further release the restriction on the accessory.

11. The stent with adjustable lumen according to any one of claims 1 to 10, wherein: The attachment extends on the body to form a bend constraint.

Images