Stent system and delivery system

Abstract

The application discloses a stent system and a delivery system. The stent system comprises a stent, a binding member connected with at least two wave coils, the binding member having a binding state and a release state, in the binding state, the binding member makes the wave coils connected with the binding member axially overlap or the axial distance between the wave coils connected with the binding member is shortened and fixed, and in the release state, the wave coils connected with the binding member are released from the fixation; and a pulling member connected with the stent, the axially overlapped wave coils in the release state have an axial overlapping length, the pulling member is pulled to shorten or eliminate the axial overlapping length, or the pulling member is pulled to increase the axial distance between the wave coils connected with the binding member. After the stent system is located at an intervention target position, the stent length can be adjusted in real time, and the stent length can be matched with the actual requirement of a portal systemic shunt.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, and more particularly to a stent system and a delivery system. Background Technology

[0002] The incidence of cirrhosis is increasing globally. In cirrhotic livers, scar tissue significantly slows blood flow from the portal vein across the liver, leading to portal hypertension. This subsequently affects the gastric coronary vein, splenic vein, and mesenteric vein. As pressure gradually increases, blood flow in the gastric coronary vein also begins to reverse, flowing against the liver. Ultimately, this leads to the following in cirrhotic patients: the spleen enlarges due to persistent congestion, resulting in hypersplenism and low platelet count; the gastric coronary vein becomes increasingly thick and thin due to repeated reverse blood flow, forming varicose veins. These varicose veins are prone to rupture and bleeding, and gastric coronary vein bleeding can easily cause death.

[0003] Transjugular intrahepatic portosystemic shunt (TIPS) is a minimally invasive interventional technique that involves puncturing the intrahepatic portal vein through the hepatic vein via the jugular vein to create a portosystemic shunt between the hepatic vein and the portal vein. This aims to reduce portal vein pressure and treat a range of complications associated with portal hypertension, such as esophageal and gastric variceal bleeding and refractory ascites. As an interventional procedure, TIPS is characterized by minimal trauma, rapid recovery, clear efficacy, and high repeatability. It has become one of the effective treatments for complications caused by cirrhosis, including portal hypertension.

[0004] In practice, due to variations in liver size and puncture channel location among individuals, the required stent length also varies. Current techniques estimate the distance between the hepatic vein and portal vein using angiography and select a stent with a length appropriate to this distance. However, individual liver differences and discrepancies in stent size matching exist; errors exist in using DSA alone to determine tortuous channels; and high positioning accuracy is required. The inherent shortening or elongation of nickel-titanium stents can lead to positional deviations, resulting in stents that are too long or too short, affecting surgical outcomes, causing re-intervention, prolonging surgery time, and increasing surgical difficulty. Summary of the Invention

[0005] The purpose of this invention is to at least solve the problem of mismatch between the size of the selected stent and the size of the stent actually needed by the patient. To address the shortcomings of the prior art, a stent system is provided.

[0006] The technical problem solved by this invention is achieved through the following technical solution:

[0007] According to a first aspect of the present invention, a support system is provided, comprising: a support including a plurality of wave coils; a restraint member connected to at least two of the wave coils, the restraint member having a restrained state and a released state, wherein in the restrained state, the restraint member causes the wave coils connected thereto to overlap axially or shorten the axial distance between them and is fixed, and in the released state, the wave coils connected to the restraint member are released from mutual fixation; and a pulling member connected to the support, wherein in the released state, the axially overlapping wave coils have an axially overlapping length, and the pulling member is pulled to shorten or eliminate the axially overlapping length, or to increase the axial distance between the wave coils connected to the restraint member.

[0008] According to the stent system proposed above, when the length of the selected stent is shorter than the actual required length, the operator can release the restraints during the in vivo operation, and then increase the length of the stent along its axis by pulling the traction component, so as to adjust the length of the stent and make the length of the stent match the actual need to establish a portosystemic shunt between the hepatic vein and the portal vein. Attached Figure Description

[0009] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. Wherein:

[0010] Figure 1 This is a schematic diagram of the structure of the bracket in Embodiment 1 of the present invention;

[0011] Figure 2 This is a schematic diagram of the support structure from another perspective of Embodiment 1 of the present invention;

[0012] Figure 3 This is a schematic diagram of the structure of the bracket in Embodiment 2 of the present invention;

[0013] Figure 4 This is a schematic diagram of the structure of the covered segment and the proximal bare stent segment in Embodiment 2 of the present invention;

[0014] Figure 5 This is a schematic diagram of the structure of the bracket in Embodiment 2 of the present invention;

[0015] Figure 6 This is a schematic diagram of the connection structure between the covered segment and the proximal bare stent segment in Embodiment 2 of the present invention;

[0016] Figure 7This is a schematic diagram of another connection structure between the covered segment and the proximal bare stent segment in Embodiment 2 of the present invention;

[0017] Figure 8 This is a schematic diagram of the supporting body and connecting line of another type of bracket in Embodiment 2 of the present invention;

[0018] Figure 9 This is a schematic diagram of the overall structure of another type of support in Embodiment 2 of the present invention;

[0019] Figure 10 This is a schematic diagram of the structure of the bracket after the first binding wire of Embodiment 3 of the present invention is in a released state and pulled by the pulling member;

[0020] Figure 11 This is a schematic diagram of the structure of the support with the first binding wire in the bound state in Embodiment 3 of the present invention;

[0021] Figure 12 This is a schematic diagram of the structure of the support with the first binding wire in the bound state in Embodiment 3 of the present invention;

[0022] Figure 13 This is a schematic diagram of the structure of the bracket in Embodiment 4 of the present invention, in which all elastic connectors are in a restrained state;

[0023] Figure 14 This is a schematic diagram of the structure of the bracket in Embodiment 4 of the present invention, in which some of the elastic connectors are in a restrained state;

[0024] Figure 15 This is a schematic diagram of the structure of the bracket in Embodiment 4 of the present invention after all the elastic connecting members are in the released state and are pulled by the pulling member;

[0025] Figure 16 This is a schematic diagram of another type of elastic connector in Embodiment 4 of the present invention;

[0026] Figure 17 This is a schematic diagram of another type of elastic connector in Embodiment 4 of the present invention;

[0027] Figure 18 This is a schematic diagram of the structure of the bracket in Embodiment 5 of the present invention, in which all the second restraint members are in a restrained state;

[0028] Figure 19a This is a partial structural diagram of the bracket in Embodiment 5 of the present invention, in which all the second restraint members are in a restrained state;

[0029] Figure 19b This is a partial structural schematic diagram of the bracket in which all the second restraint members are in a restrained state from another perspective of Embodiment 5 of the present invention;

[0030] Figure 20 for Figure 19a A magnified view of part A in the middle;

[0031] Figure 21 This is a schematic diagram of the conveying system according to Embodiment 6 of the present invention;

[0032] Figure 22 This is a partial structural diagram of the conveying system of Embodiment 6 of the present invention;

[0033] Figure 23 This is a schematic diagram of the cross-section of the double-lumen tube in Embodiment 6 of the present invention;

[0034] Figure 24 This is a schematic diagram of the release process of the conveying system in Embodiment 6 of the present invention;

[0035] Figure 25 This is a schematic diagram of the release process of the conveying system in Embodiment 7 of the present invention;

[0036] Figure 26 This is a schematic diagram of the structure of the bracket in Embodiment 7 of the present invention;

[0037] Figure 27 This is a partial structural schematic diagram of the waveguide in Embodiment 7 of the present invention;

[0038] Figure 28 This is a partial structural diagram of another wave loop according to Embodiment 7 of the present invention.

[0039] The labels in the attached diagram are as follows:

[0040] 100. Support system;

[0041] 10. Stent; 11. Support body; 111. Proximal bare stent segment; 112. Distal bare stent segment; 113. Covered segment; 1131. Intermediate wavelet; 1132. Head wavelet; 11321. Circular structure; 101. Wavelet; 1011. Male structure; 1012. Female structure; 1013. Gap; 12. Covered portion; 121. Outer cover; 122. Inner cover; 13. Imaging point; 14. Anti-coating coating; 15. PTFE line; 16. Connecting line;

[0042] 20. Restraint component; 21. First restraint wire; 22. Elastic connector; 23. Second restraint wire;

[0043] 30. Pulling components;

[0044] 600. Conveying system;

[0045] 61. Sheath core; 611. Tip; 612. Double-lumen tube; 613. Anti-shortening block; 614. Limiting block; 615. Balloon; 616. Connecting seat; 617. First cavity; 618. Second cavity; 619. Hole; 62. Outer sheath;

[0046] 711. Barbs; 713. Junction between liver parenchyma and hepatic vein; 714. Opening of hepatic vein;

[0047] 81. Hepatic vein; 82. Liver parenchyma; 83. Portal vein. Detailed Implementation

[0048] Exemplary embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the invention and to fully convey the scope of the invention to those skilled in the art.

[0049] It should be understood that the terminology used herein is for the purpose of describing particular exemplary embodiments only and is not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms “a,” “an,” and “described” as used herein may also include the plural forms. The terms “comprising,” “including,” “containing,” and “having” are inclusive and therefore indicate the presence of the stated features, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components, and / or combinations thereof. The method steps, processes, and operations described herein are not construed as requiring them to be performed in a particular order described or illustrated unless the order of performance is explicitly indicated. It should also be understood that additional or alternative steps may be used.

[0050] Although terms such as first, second, third, etc., may be used in this document to describe multiple elements, components, regions, layers, and / or segments, these elements, components, regions, layers, and / or segments should not be limited by these terms. These terms may be used only to distinguish one element, component, region, layer, or segment from another. Unless the context clearly indicates otherwise, terms such as "first," "second," and other numerical terms used herein do not imply order or sequence. Therefore, the first element, component, region, layer, or segment discussed below may be referred to as the second element, component, region, layer, or segment without departing from the teachings of the exemplary embodiments.

[0051] For ease of description, spatial relative terms may be used in the text to describe the relationship of one element or feature relative to another element or feature, as shown in the figure. These relative terms include, for example, "inside," "outside," "middle," "outer," "below," "below," "above," "over," etc. Such spatial relative terms are intended to include different orientations of the device in use or operation, other than those depicted in the figure. For example, if the device in the figure rotates, then an element described as "below other elements or features" or "below other elements or features" will subsequently be oriented "above other elements or features" or "above other elements or features." Therefore, the example term "below" can include both upper and lower orientations.

[0052] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between the components; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0053] It should be noted that the terms "distal" and "proximal" are used as directional terms, which are commonly used in the field of interventional medical devices. "Distal" refers to the end furthest from the operator during the procedure, while "proximal" refers to the end closest to the operator. Axial direction refers to the direction parallel to the line connecting the center of the distal and proximal ends of the medical device; radial direction refers to the direction perpendicular to the aforementioned axial direction.

[0054] Please combine Figure 1 , Figure 11 , Figure 13 and Figure 18 As shown, this embodiment of the invention provides a stent system 100, which includes a stent 10, a restraint member 20, and a traction member 30. In this embodiment, the stent system 100 is used for transjugular intrahepatic portosystemic shunt. In other embodiments, the stent system 100 can be used in various blood vessels, trachea, or cavities.

[0055] Among them, combined Figure 2The stent 10 includes a covered segment 113 and a proximal bare stent segment 111 and a distal bare stent segment 112 connected to the proximal and distal ends of the covered segment 113, respectively. The covered segment 113 includes an outer covered layer 121, an inner covered layer 122, and multiple bare coils 101 sandwiched between the outer covered layer 121 and the inner covered layer 122. The proximal bare stent segment 111 and the distal bare stent segment 112 are each woven from multiple coils 101, and the material of the coils 101 includes, but is not limited to, nickel-titanium alloy wire. The stent 10 is used to establish a portosystemic shunt between the hepatic vein and the portal vein to reduce portal vein pressure and treat a series of portal hypertension complications such as esophageal and gastric variceal bleeding and refractory ascites. In detail, all the wave coils 101 in the stent 10 are arranged sequentially along the axial direction of the stent 10 and form the support body 11 of the stent 10. The support body 11 composed of wave coils 101 establishes a channel of appropriate diameter through its own expansion or contraction characteristics for blood drainage, that is, to drain venous blood in the portal vein to the hepatic vein, thereby reducing portal vein pressure.

[0056] The stent 10 proposed in this embodiment of the invention possesses excellent flexibility in its support body 11 through a structure formed by overlapping multiple periodically distributed corrugated coils in the axial direction, allowing it to adapt to channels with varying degrees of curvature. Here, overlapping refers to adjacent corrugated coils hooking together at positions where crests face crests, crests face troughs, or troughs face troughs. In other embodiments, the stent 10 may include one of a proximal bare stent segment 111 and a distal bare stent segment 112.

[0057] The covering segment 113 is made of elastic polymer materials such as expanded polytetrafluoroethylene, polyester fiber, or polyurethane. The outer covering 121 and the inner covering 122 are connected by adhesive or thermoforming, which can firmly wrap the coil 101 inside, forming a reliable and non-separable whole. The covering segment 113 is placed in the liver parenchyma, which plays a role in isolating bile leakage and preventing liver tissue from proliferating into the stent 10 and blocking the shunt channel of the component. The distal bare stent segment 112 is placed in the portal vein, and the proximal bare stent segment 111 is placed in the hepatic vein. The proximal bare stent segment 111 and the distal bare stent segment 112 are connected to the covering segment 113 in the liver parenchyma, preventing the movement of the liver and blood vessels from closing the opening of the covering segment 113, and also playing a role in positioning and fixing the entire stent system 100. In this embodiment of the invention, the provision of the proximal bare stent segment 111 and the distal bare stent segment 112 reduces the proportion of the implanted covered segment 113, allowing the liver to receive adequate blood flow and reducing the risk of acute liver failure.

[0058] Furthermore, such as Figure 11As shown, the restraint member 20 is connected to at least two coils 101. The restraint member 20 has a restrained state and a released state. In the restrained state, the restraint member 20 causes the axial overlap or axial distance between the coils 101 connected to it to be shortened and fixed. In the released state, the coils connected to the restraint member 20 are released from mutual fixation. The traction member 30 is connected to the stent 10. In the released state, the axially overlapping coils 101 have an axially overlapping length. Pulling the traction member 30 can shorten or eliminate the axially overlapping length, or pull the traction member 30 can increase the axial distance between the coils 101 connected to the restraint member 20, thereby increasing the axial length of the stent 10. This achieves the purpose of adjusting the length of the stent 10 in real time within the body, so that the length of the stent 10 can match the actual needs of establishing a portosystemic shunt between the hepatic vein and the portal vein.

[0059] After implanting the stent system 100, depending on the actual length requirement for establishing a portosystemic shunt between the hepatic vein and the portal vein, one can choose to not release the restraint, partially release the restraint, or completely release the restraint. By controlling the pulling distance of the traction member 30, the axial overlap between the stent coils can be shortened or eliminated, so that the length of the stent 10 can be adjusted in real time during the actual operation to match the actual needs.

[0060] The technical solution of the present invention will be further described in detail below with reference to specific embodiments.

[0061] Example 1

[0062] Combination Figure 1 and Figure 2 As shown, according to an embodiment of the present invention, a support system 100 is provided, the support system 100 including a support 10.

[0063] Specifically, the stent 10 includes: a support body 11, a covered portion 12, a radiopaque point 13, and an anticoagulant coating 14. The covered portion 12 consists of an outer covered layer 121 and an inner covered layer 122. The stent 10 is divided into three segments: a proximal bare stent segment 111, a distal bare stent segment 112, and a covered portion 113. The support body 11 includes the support body for the proximal bare stent segment 111, the support body for the distal bare stent segment 112, and the support body for the covered portion 113.

[0064] The overall framework of the covered stent 10 is the support body 11, which is woven from nickel-titanium alloy wire and consists of multiple periodically distributed wave loops along the axial direction. The function of the support body 11 is to establish a channel of appropriate diameter through its own expansion and contraction properties for blood drainage, specifically for the portal vein 83 (see...). Figure 24 The venous blood in the liver is drained into the hepatic vein 81 (see...) Figure 24This reduces portal vein pressure 83. Furthermore, the structure formed by multiple periodically distributed wave loops along the axial direction gives the support body 11 excellent flexibility to adapt to channels with varying degrees of curvature. The length of the support body 11 ranges from 50mm to 120mm, and its diameter ranges from 5mm to 14mm.

[0065] The support body 11 is located between the outer film 121 and the inner film 122, and the inner and outer films 121 only partially cover the support body 11. The covering position is located in the middle section of the support body 11 along its length, with the bare stent sections of the support body 11 at both ends. The length range of the proximal bare stent section 111 and the distal bare stent section 112 is 10mm to 30mm. The film material includes, but is not limited to, expanded polytetrafluoroethylene, polyester fiber, or elastic polymer materials such as polyurethane. The inner and outer films 121 are connected by adhesive or hot pressing, which can firmly wrap the support body 11 inside, forming a reliable and non-separable whole. In other embodiments, only the outer film 121 or the inner film 122 may be provided.

[0066] During use, the covered portion 12 is placed within the liver parenchyma 82, serving to prevent bile leakage and tissue proliferation into the support structure 11. The distal bare stent segment 112 is placed within the portal vein 83, and the proximal bare stent segment 111 is placed within the hepatic vein 81. The proximal and distal bare stent segments 111 and 112 connect to the covered portion 113 within the liver parenchyma 82. The proximal and distal bare stent segments 111 and 112 prevent liver and blood vessel movement from closing the opening of the covered portion 113 and also serve to position and fix the entire stent system 100. The placement of the proximal and distal bare stent segments 111 and 112 in this invention reduces the proportion of the implanted covered portion 113, allowing the liver to receive adequate blood flow and reducing the risk of acute liver failure.

[0067] To enhance the imaging effect of the nickel-titanium stent and improve the accuracy of positioning the intrahepatic covered portion 12 during use, imaging points 13 are provided at the junctions of the covered segment 113 with the proximal bare stent segments 111 and 112. The imaging points 13 are made of at least one of the following materials: gold, platinum-iridium alloy, and tantalum. The imaging points 13 are located on the support body of the proximal and distal bare stent segments 111 and are fixed to the waveguide of the support body by winding. The imaging points 13 can be spaced apart or arranged throughout an entire waveguide.

[0068] The inner surface of the inner membrane 122 is covered with an anticoagulant coating 14. The coating material includes phosphocholine or heparin, which is covalently bonded to the surface of the device to play an anticoagulant role.

[0069] In fabricating the support 10 proposed in this embodiment, the support body 11 is first woven onto a mold using nickel-titanium wire, with developing points 13 wrapped around it during the weaving process. The support body 11 is then heat-treated for shaping. Next, an inner coating 122 is placed on the coating mold, and the support body 11 is then fitted onto the inner coating 122. An outer coating 121 is then wrapped around the outer surface of the support body 11. Finally, the wrapped support is placed in a high-temperature furnace for sintering, causing the inner and outer coatings to bond together. After sintering, the support is cleaned and coated with an anti-condensation coating 14.

[0070] Example 2

[0071] The differences between Example 2 and Example 1 will be described below. The similarities or similarities between Example 2 and Example 1 will not be repeated here.

[0072] Combination Figure 3 , Figure 4 and Figure 5 As shown, according to an embodiment of the present invention, a support system 100 is provided, the support system 100 including a support 10.

[0073] The stent 10 includes: a support body 11 composed of multiple wave coils, a coating portion 12, a radiopaque spot 13, and an anticoagulant coating 14. The coating portion 12 is composed of an outer coating 121 and an inner coating 122. The stent 10 is divided into three segments: a proximal bare stent segment 111, a distal bare stent segment 112, and a coating segment 113. The support body 11 includes the support body for the proximal bare stent segment 111, the support body for the distal bare stent segment 112, and the support body for the coating segment 113.

[0074] In this embodiment, the proximal bare stent segment 111, the distal bare stent segment 112, the covered portion 12, and the anticoagulant coating 14 are the same as in Embodiment 1. The difference between this embodiment and Embodiment 1 lies in the structure and material of the covered portion 113.

[0075] The support body of the covered segment 113 is made of medical-grade stainless steel, cobalt-chromium alloy, or platinum-chromium alloy, and is opened by a balloon dilation catheter of the corresponding diameter during use. The lengths of the proximal bare stent segment 111 and the distal bare stent segment 112 range from 10mm to 30mm, and the diameters range from 5mm to 14mm. The lengths of the proximal bare stent segment 111 and the distal bare stent segment 112 can be set differently. The length of the support body of the covered segment 113 is 30mm to 100mm, and the diameter ranges from 5mm to 14mm. The diameter of the covered segment 113 can be set differently from the diameter of the proximal bare stent segment 111 or the distal bare stent. In this embodiment, the stent 10 has the characteristic that the diameter of the covered segment 113 is controllable, and it has better radiopaqueness, eliminating the need for additional radiopaque points 13.

[0076] like Figure 4As shown, the supporting body of the coated section 113 includes a middle corrugated coil 1131 and a head corrugated coil 1132. Each corrugated coil is independent and spaced 0.2mm to 2mm apart along the axial direction of the support 10. Two adjacent corrugated coils are placed with alternating crests and troughs. All independent corrugated coils are connected together by an inner coating 122 and an outer coating 121. In this embodiment, the support 10, due to the spaced corrugated coils, the absence of metal connections, and the space created by the alternating crests and troughs, exhibits excellent adaptability to curved channels and will not straighten again over time.

[0077] A circular ring structure 11321 is provided at one end of each of the two end beaded coils. The nickel-titanium wires of the nickel-titanium support body of the proximal bare stent segment 111 or the distal bare stent segment 112 pass through each circular ring structure 11321, serving to connect the proximal bare stent segment 111, the distal bare stent segment 112 (nickel-titanium section), and the coated segment 113. This connection method, being a nested structure, allows for some flexibility and does not restrict the bending of the support body of the proximal bare stent segment 111 or the distal bare stent segment 112, or the coated segment 113, in any direction. The diameter of the circular ring structure 11321 ranges from 0.1 mm to 0.5 mm. To avoid risks caused by the placement of the circular ring structure 11321 and the movement of the nickel-titanium wires, the width of the rod in the circular ring structure 11321 and the rounded corners at the transition points are widened. The length of the coated segment 113 is determined by the number of intermediate beaded coils 1131. In this embodiment, the total length and diameter of the support 10 can be kept the same as in Embodiment 1.

[0078] Figure 5 This is a schematic diagram showing that the coated section 113 in the middle of this embodiment can achieve a variable diameter. Please refer to... Figure 5 and Figure 24As shown, when the stent system 100 is used clinically, the most common complication is hepatic encephalopathy. The incidence of hepatic encephalopathy in patients who successfully undergo Tips (transjugular intrahepatic portosystemic shunt) is approximately 5%-35%. Studies have shown that gradually reducing portosystemic pressure to 25%-50% instead of a sudden drop can effectively reduce the incidence of hepatic encephalopathy. In existing technologies, the expansion force of the nickel-titanium metal (i.e., the wavelet) is restrained by the constraint force of the covering portion 12 (i.e., the outer covering 121 and the inner covering 122), and the desired diameter is achieved by balloon dilation of the membrane. However, during long-term use, the constraint force provided by the polymer membrane is insufficient to resist the continuous chronic outward force of the nickel-titanium metal, making it difficult for existing stents to avoid long-term diameter enlargement. In the stent 10 proposed in this application, the diameter control of the covering segment 113 is no longer achieved through membrane deformation; the deformation of the covering portion 12 is an additional, accompanying change. The actual component responsible for diameter adjustment is medical-grade stainless steel, cobalt-chromium alloy, or platinum-chromium alloy (i.e., the corrugated coil). The corrugated coil's superior plastic deformation capability, and the work hardening that occurs during plastic deformation, effectively resists the compression of the stent caused by liver movement when the final diameter is used. Furthermore, the corrugated coil supported by these metals does not possess hyperelastic properties, thus avoiding the problem of diameter enlargement due to continuous, chronic external forces.

[0079] In this embodiment, the initial diameter of the covered segment 113 can be 10% to 30% smaller than the diameter of the proximal bare stent segment 111 or the distal bare stent segment 112. After implantation into the liver, the proximal bare stent segment 111 or the distal bare stent segment 112 is first inflated for positioning, and then the covered segment 113 is expanded to a smaller diameter using balloon dilation. If the pressure reduction is still insufficient, the covered segment 113 can be expanded again using balloon dilation. Due to the plastic deformation characteristics, the enlarged diameter will remain almost unchanged, increasing the amount of blood passing through and further reducing the pressure. By repeating the above operation, the physician only needs to change balloons of different sizes to achieve precise pressure control. This design can accurately control the shunt diameter and prevent phenomena such as hepatic encephalopathy caused by the gradual increase in diameter of nickel-titanium stents in the later stages, as is common in existing technologies.

[0080] The manufacturing method of the stent 10 in this embodiment is as follows: First, the corrugations of the support body of the coated section 113 are laser-cut, and then surface treatments such as pickling, heat treatment, and polishing are performed to remove cutting slag and obtain a smooth surface. Next, the head-end corrugations 1132 are fitted onto the braiding mold, and the nickel-titanium support bodies of the proximal bare stent section 111 and the distal bare stent section 112 are braided and heat-set. Then, the inner coating 122 is wrapped around the coating mold, and the heat-set proximal bare stent section 111 and the distal bare stent section 112, along with the corrugations of the coated section 113, are fitted onto the inner coating 122 at certain intervals, and the outer coating 121 is then wrapped around them. The remaining processes are consistent with those in Embodiment 1. During use, first release the bare stent at the portal vein 83 end (i.e., the distal bare stent segment 112) and the bare stent at the hepatic vein 81 end (i.e., the proximal bare stent segment 111) for positioning. Then, select a balloon of appropriate diameter to dilate the intermediate covered segment 113 and observe the real-time shunt effect. If it is not as expected, the doctor can continue to replace it with a larger diameter balloon to continue dilating the intermediate covered segment 113.

[0081] In some embodiments, such as Figure 6 As shown, the connection between the proximal bare stent segment 111 or the distal bare stent segment 112 and the covered segment 113 can also be achieved by suturing with PTFE (Polytetrafluoroethylene) thread, stitching the circular ring structure 11321 at the head end of the proximal bare stent segment 111 or the distal bare stent segment 112 and the covered segment 113 together. During manufacturing, it is not necessary to add the head end corrugation 1132 of the covered segment 113 when weaving and shaping the proximal bare stent segment 111 or the distal bare stent segment 112, thus simplifying the process and minimizing the impact on the covered segment 113. This embodiment only provides the suture connection method and does not limit the specific suturing and knotting method.

[0082] In some embodiments, such as Figure 7 As shown, the connection between the proximal bare stent segment 111 or the distal bare stent segment 112 and the covered segment 113 can also be achieved by laser welding. The proximal bare stent segment 111 or the distal bare stent segment 112 and the covered segment 113's end bead 1132 are connected together by laser welding. This requires a one-to-one correspondence and welding of the protruding parts of the proximal bare stent segment 111 or the distal bare stent segment 112 and the covered segment 113. This simplifies the manufacturing process and minimizes the impact on the covered segment 113. Furthermore, laser welding provides a more robust and reliable connection.

[0083] In some embodiments, such as Figure 8 and Figure 9As shown, an axially extending connecting line 16 is added to the coated section 113. The axial connecting line 16 is sequentially wound around the corrugations of multiple coated sections 113 along the axial direction of the support 10, making the connection between the head corrugation 1132 of the coated section 113 and the corrugations of other parts of the coated section 113 more secure, without compromising the flexibility of the support 10. Specifically, the axial connecting line 16 of the coated section 113 connects the individual corrugations along the length of the coated section 113 by winding the lines together through the corrugation crests of one corrugation to the crests of another corrugation, and / or through the corrugation troughs of one corrugation to the troughs of another corrugation, and / or through the corrugation crests of one corrugation to the troughs of another corrugation. The material of the connecting line 16 includes, but is not limited to, polytetrafluoroethylene (PTFE).

[0084] During manufacturing, after wrapping the inner coating 122 and attaching the proximal bare support segment 111, the distal bare support segment 112, and the coating segment 113, the corresponding peaks or troughs of the waveguide are wound and connected on the coating segment 113 using connecting lines 16. Then, the outer coating 121 is wrapped, ensuring it is completely aligned with the inner coating 122. The wrapped structure is then sintered in a high-temperature furnace, bonding the inner and outer coatings together. Finally, the sintered support is cleaned and coated with an anti-condensation coating 14. In this embodiment, by providing connecting lines 16 on the coating segment 113, the risk of the waveguide detaching from the coating portion 12 can be reduced.

[0085] Example 3

[0086] The differences between Example 3 and Examples 1 and 2 will be described below. The similarities or similarities between Example 3 and Examples 1 and 2 will not be repeated here.

[0087] Combination Figure 10 , Figure 11 and Figure 12 As shown, according to an embodiment of the present invention, a support system 100 is provided. The support system 100 includes a support 10, a restraint member 20 and a tension member 30. The support 10 in this embodiment has the same structure as the support 10 in embodiment 1 or embodiment 2, and will not be described again here.

[0088] The restraint member 20 is connected to at least two corrugations in the proximal bare stent segment 111 and / or the covered segment 113. The restraint member has a restrained state and a released state. In the restrained state, the restraint member 20 limits and fixes the axial distance between the corrugations 101 connected to it. In the released state, the corrugations 101 connected to the restraint member 20 can be mutually released from fixation. It is understood that the restraint member 20 can be connected to at least two corrugations in the proximal bare stent segment 111, or to at least two corrugations in the covered segment 113, or simultaneously to corrugations in both the proximal bare stent segment 111 and the covered segment 113. In other embodiments, the restraint member can also be connected to at least two corrugations in the distal bare stent segment 112, or to corrugations in different stent segments.

[0089] Specifically, the restraint member 20 includes a first restraint wire 21. In the restrained state, the first restraint wire 21 is wound around two wave loops 101a and 101c, and applies opposing converging restraint forces to the two wave loops along the axial direction of the support 10. The two wave loops connected to the first restraint wire 21 are subjected to the force of the first restraint wire 21 and are displaced axially, causing them to move closer to each other. This shortens the axial distance between the two wave loops 101a and 101c connected to the first restraint wire 21, and the first restraint wire 21 fixes the wave loops 101a and 101c. In the released state, the first restraint wire 21 is released from fixation with the wave loops 101a and 101c, and the wave loops 101a and 101c lose their restraint force. The pulling member 30 is connected to the proximal end of the support 10. In the released state, the pulling member 30 can pull the proximal end of the support 10 to move towards the proximal side, and drive the wave coils 101a and 101c connected to the first binding wire 21 to move axially toward the proximal side, and make the two wave coils 101a and 101c connected to the first binding wire 21 move away from each other axially, so as to increase the axial distance between the wave coils 101a and 101c connected to the first binding wire 21, thereby increasing the axial length of the support 10.

[0090] In this embodiment, both the first binding wire 21 and the pulling member 30 are in the form of threads, and the pulling member 30 is wound around the proximal end of the bare support. It can be understood that in order to achieve the effect of elongating the support 10, the pulling member 30 is closer to the proximal end than the binding member 20. Based on this, the pulling member 30 can be wound around any position on the support 10.

[0091] Among them, such as Figure 11As shown, coils 101a, 101b, and 101c are partial coils constituting the support body of the proximal bare stent segment 111. In this embodiment, the support body constituting the proximal bare stent segment 111 is woven from nickel-titanium alloy wire, and adjacent coils such as coils 101a and 101b are overlapped during weaving, providing good freedom of movement and thus preventing stent deformation during assembly and operation. Due to this overlapped structure, the proximal bare stent segment 111 of the hepatic vein 81 has a certain range of motion, which is the maximum axial length of the support body of the proximal bare stent segment 111. Furthermore, the support body of the proximal bare stent segment 111 can undergo a certain amount of axial compression within this range, but cannot extend beyond the range.

[0092] In this embodiment, the first binding wire 21 is wound along the axial direction of the support 10 on the crests of the spaced-apart wave coils 101a and the troughs of the wave coils 101c. In the binding state, the first binding wire 21 applies opposing binding forces to the wave coils 101a and 101c, causing the wave coils 101a and 101c to move closer to each other along the axial direction, shortening the axial distance between the wave coils 101a and 101c, and causing the wave coils 101a and 101c to overlap with the wave coil 101b, thereby reducing the length dimension of the support body 11 formed by the wave coils 101a, 101b and 101c along the axial direction. Understandably, when the first binding wire 21 is released, it detaches from the wave coils 101a and 101c. By pulling the traction member 30, wave coil 101c moves towards the proximal end, thereby causing wave coils 101a and 101c to move away from each other. This increases the axial length of the support body 11 composed of wave coils 101a, 101b, and 101c, thus adjusting the axial length of the support body 11. Understandably, in this embodiment, the two spaced-apart wave coils refer to two non-overlapping wave coils. Specifically, wave coils 101a and 101c bound by the first binding wire 21 can be adjacent or non-adjacent, as long as the axial length of the support body 11 can be adjusted.

[0093] Furthermore, the first binding wire 21 is sequentially wound around multiple peaks of wave coil 101a and multiple troughs of wave coil 101c along the circumference of the stent 10. In the bound state, a binding force is applied radially towards the stent 10 to wave coils 101a and 101c along the circumference of the stent 10, reducing the diameter of wave coils 101a and 101c in the bound state. In this embodiment, the ratio of the diameter of the wave coils in the bound state to the diameter of the wave coils in the natural state is in the range of 80% to 90%. The natural state refers to the stent not being bound by the binding element and being in a fully deployed state. With this configuration, when the release position is not ideal, since the stent 10 is not completely in contact with the blood vessel wall, the release position can be adjusted again through the delivery system.

[0094] In this embodiment, the method for compressing the near-end bare support is as follows: symmetrically arranged and spaced-apart corrugations 101a and 101c are brought close together in the axial direction and fixed with a first binding wire 21 woven from PTFE or PET fibers (polyethylene terephthalate). In the circumferential direction, the first binding wire 21 is wound around the crest of each corrugation 101a and the trough of each corrugation 101c. The first binding wire 21, which performs the winding action, is continuously wound in the circumferential direction and tightened to a certain extent, so that the diameter of the support body 11 formed by corrugations 101a, 101b, and 101c is between 80% and 90% of its natural diameter. Finally, both ends of the first binding wire 21 are fixed to the conveying system 600. When it is necessary to release the first binding wire 21, simply release one end of the first binding wire 21 from the delivery system 600, pull the other end of the first binding wire 21 to release the first binding wire 21 from the support 10, and then remove it from the body.

[0095] In other embodiments, the first binding wire 21 may be wound on the wave loop at locations other than the crests or troughs, such as on the connecting rod between the crests and troughs. The first binding wire 21 may be wound on two or more wave loops.

[0096] Furthermore, such as Figure 12 As shown, the support system 100 includes a plurality of first binding wires 21 spaced apart along the axial direction of the support. Two corrugated coils spaced apart in the support 10 form a group, and the two corrugated coils in each group are bound by one first binding wire 21 to facilitate length adjustment at different positions of the support. In this embodiment, "a plurality of" means at least two.

[0097] Specifically, when the number of wave loops in the proximal bare stent segment 111 of the hepatic vein 81 is relatively large, two or more first binding wires 21 can be set and bound to different wave loops respectively, so that the proximal bare stent segment 111 has multiple axially contracting parts. It is conceivable that when the stent 10 is released from the delivery system 600, the proximal bare stent segment 111 is not finally placed in the hepatic vein 81 before any of the first binding wires 21 are released, and due to the binding of the first binding wires 21, the diameter of the proximal bare stent segment 111 is small and cannot completely adhere to the vessel wall. During the process of releasing the first restraint wire 21, the first restraint wire 21 located proximally is first released, increasing the radial diameter of the proximal bare stent segment 111 so that it can adhere tightly to the vessel wall. Simultaneously, the traction member 30 is pulled towards the proximal side, increasing the axial length of the proximal bare stent segment 111 until its axial length meets the required length, ensuring that the proximal bare stent segment 111 is securely fixed within the hepatic vein 81, thus completing the implantation of the stent system 100. After releasing one first restraint wire 21, and with the connected coils 101a and 101c completely separated to their maximum travel, the physician can observe whether the length of the proximal bare stent segment 111 within the hepatic vein 81 is appropriate. If the length of the proximal bare stent segment 111 is still less than the required length, other first restraint wires 21 can be released, and the above process of adjusting the length of the proximal bare stent segment 111 can be repeated until the appropriate coverage length is achieved. Furthermore, if there are still other first restraint wires 21 that have not been released after the length adjustment of the proximal bare stent segment 111 is completed, they can be released, but it is not necessary to pull the traction member 30 to adjust its length.

[0098] It should be noted that the proximal bare stent segment 111 with its denser wave pattern will not affect the hepatic vein 81. Finally, retract the traction element 30 into and out of the delivery system 600.

[0099] In some embodiments, the first binding wire 21 may also be wound around the corrugated coil of the covered section 113 or the distal bare stent section 112 to facilitate adjustment of the unfolded length of the covered section 113 and the distal bare stent section 112. The winding and adjustment methods of the first binding wire 21 are the same as those of the winding and adjustment methods of the proximal bare stent section 111, and will not be described again here.

[0100] Example 4

[0101] The differences between Example 4 and Examples 1 and 2 will be described below. The similarities or similarities between Example 4 and Examples 1 and 2 will not be repeated here.

[0102] Combination Figure 13 , Figure 14and Figure 15 As shown, according to an embodiment of the present invention, a support system 100 is provided. The support system 100 includes a support 10, a restraint member 20 and a tension member 30. The support 10 in this embodiment has the same structure as the support 10 in embodiment 1 or embodiment 2, and will not be described again here.

[0103] The restraint member 20 is connected to at least two corrugations 101 in the proximal bare stent segment 111 and / or the covered segment 113. The restraint member 20 has a restrained state and a released state. In the restrained state, the restraint member defines and fixes the corrugations 101 connected to it to axially overlap. In the released state, the corrugations 101 connected to the restraint member 20 are released from mutual fixation. It is understood that the restraint member 20 can be connected to at least two corrugations in the proximal bare stent segment 111, or to at least two corrugations in the covered segment 113, or simultaneously to corrugations in both the proximal bare stent segment 111 and the covered segment 113. In other embodiments, the restraint member can also be connected to at least two corrugations in the distal bare stent segment 112, or to corrugations in different stent segments.

[0104] Specifically, the restraint member 20 includes an elastic connector 22, which can be a rod-shaped member. Both ends of the elastic connector 22 are connected to the crests and troughs of two adjacent wave loops, respectively. In the restrained state, along the radial direction of the support 10, the elastic connector 22 and the two wave loops at least partially connected to it overlap, causing the elastic connector 22 and the two wave loops connected to it to fold along the axial direction of the support 10. The elastic connector 22 provides a certain supporting force to maintain the overlapping state of the adjacent wave loops.

[0105] The traction member 30 is connected to the proximal end of the stent 10. After the distal bare stent segment 112 in the portal vein 83 is positioned, during the process of retracting the outer sheath to release the remaining stent system 100, the traction member 30 is pulled axially towards the proximal side, and the wave coil connected to the elastic connector 22 is moved towards the proximal side. During this process, the elastic connector 22 is deformed and moved, so that the elastic connector 22 is switched to the released state. In the released state, along the axial direction of the stent 10, the elastic connector 22 and the two wave coils connected to the elastic connector 22 are arranged sequentially, so that the elastic connector 22 and the two wave coils connected to the elastic connector 22 are extended. The axial length of the elastic connector 22 and the two wave coils connected to the elastic connector 22 increases until the length required to construct the shunt channel is reached.

[0106] Furthermore, the stent system 100 includes multiple elastic connectors 22, with at least two elastic connectors 22 forming a group. The elastic connectors 22 in each group are sequentially spaced along the circumference of the stent 10. Along the axial direction of the stent 10, multiple corrugated coils are sequentially connected to multiple groups of elastic connectors 22. In this embodiment, if the length of the stent system 100 in its fully released state is too long, during the release of the elastic connectors 22, by controlling the axial pulling length of the pulling member 30, a portion of the elastic connectors 22 can be released, allowing part of the corrugated coils of the proximal bare stent segment 111 to extend, while the remaining portion of the proximal bare stent segment 111 remains folded.

[0107] In this embodiment, the elastic connector 22 is connected to the wave coil by welding or gluing.

[0108] In some embodiments, the elastic connector 22 may also be disposed on the corrugated ring of the covered section 113 to facilitate adjustment of the unfolded length of the covered section 113. The arrangement and adjustment of the elastic connector 22 are the same as those of the proximal bare stent section 111, and will not be described again here.

[0109] In other embodiments, such as Figure 16 and Figure 17 As shown, the elastic connector 22 can also be a helical spring. The two ends of the helical spring in a compressed state are connected to the crests and troughs of the two wave coils, respectively, which can keep the helical spring and the two wave coils in a bound state. Only an external force (by pulling the traction component) can change the bound state to a free state.

[0110] Example 5

[0111] The differences between Example 5 and Examples 1 and 2 will be described below. The similarities or similarities between Example 5 and Examples 1 and 2 will not be repeated here.

[0112] Combination Figure 18 , Figure 19a , Figure 19b and Figure 20 As shown, according to an embodiment of the present invention, a support system 100 is provided. The support system 100 includes a support 10, a restraint member 20 and a tension member 30. The support 10 in this embodiment has the same structure as the support 10 in embodiment 1 or embodiment 2, and will not be described again here.

[0113] The restraint member 20 is connected to at least two corrugations in the proximal bare stent segment 111 and / or the covered segment 113. The restraint member has a restrained state and a released state. In the restrained state, the restraint member 20 defines and fixes the axial overlap between the corrugations 101 connected to it. In the released state, the corrugations 101 connected to the restraint member 20 are released from mutual fixation. The traction member 30 is connected to the proximal end of the stent 10. Understandably, in order to achieve the effect of elongating the stent 10, the traction member 30 is closer to the proximal end than the restraint member 20. Based on this, the traction member 30 can be positioned at any location on the stent 10.

[0114] Specifically, two adjacent wave coils are respectively provided with a male structure 1011 and a female structure 1012 that can be plugged in and mated, and the male structure 1011 and the female structure 1012 have a gap 1013 in the plugged state; the restraint member 20 includes a second restraint wire 23. In the restrained state, the male structure 1011 is inserted into the female structure 1012, and part of the second restraint wire 23 is located between the male structure 1011 and the female structure 1012 and fills the gap 1013 so that the male structure 1011 and the female structure 1012 are engaged. In the unrestrained state, the second restraint wire 23 comes out from the gap 1013 and drives the male structure 1011 and the female structure 1012 to disengage.

[0115] The male structure 1011 and the female structure 1012 can be positioned at any position on the two wave coils. When two adjacent wave coils are connected by the male structure 1011 and the female structure 1012, the two wave coils overlap at least partially in the radial direction of the support 10, causing the two wave coils to be in a contracted state in the axial direction. In the disengaged state, when the male structure 1011 and the female structure 1012 are disengaged, the pulling member 30 can be pulled to move towards the proximal end, causing the two wave coils to extend in the axial direction, thereby increasing the axial length of the support 10 in the disengaged state and achieving the purpose of adjusting the length of the support 10.

[0116] It should be noted that when the corrugated coils in the proximal bare stent segment 111 are configured with male structures 1011 and female structures 1012, the corrugated coils in the proximal bare stent segment 111 are connected as a whole by overlapping and braiding nickel-titanium wires. Therefore, even if the male structure 1011 and female structure 1012 of two adjacent corrugated coils are separated, the two adjacent corrugated coils will not detach from the support body 11. When the corrugated coils in the covered segment 113 are configured with male structures 1011 and female structures 1012, the corrugated coils in the covered segment 113 are indirectly connected at least through the inner covered layer 122 and the outer covered layer 121. Therefore, even if the male structure 1011 and female structure 1012 of two adjacent corrugated coils are separated, the two adjacent corrugated coils will not detach from the covered segment 113. In one embodiment, the male structure 1011 and female structure 1012 can also be configured in the corrugated coils of the distal stent segment 112. In one embodiment, the male structure 1011 and the female structure 1012 may be respectively arranged in different support segments.

[0117] In this context, male structure 1011 and female structure 1012 refer to structural forms capable of being plugged in and mated. For example, female structure 1012 can be a groove, and male structure 1011 can be a protrusion that plugs in and mates with the groove. The groove can extend axially or radially along the support 10. Alternatively, female structure 1012 can be a through hole along the axial direction of the support 10, and male structure 1011 can be a rod-shaped protrusion along the axial direction of the support 10 that plugs in and mates with the through hole. Male structure 1011 and female structure 1012 can also be configured as other forms of plugging structures, which are not specifically limited here.

[0118] It should also be noted that, since there is a gap 1013 between the male structure 1011 and the female structure 1012 when the male structure 1011 is inserted into the female structure 1012, a firm connection cannot be formed between the male structure 1011 and the female structure 1012. Therefore, by clamping part of the second binding wire 23 between the male structure 1011 and the female structure 1012, the male structure 1011 together with the second binding wire 23 and the female structure 1012 form an interference fit, thereby forming a relatively firm snap-fit ​​connection between the male structure 1011 and the female structure 1012, so as to ensure that the two adjacent wave coils can maintain an axially contracted state under the binding state.

[0119] Please combine Figure 18 and Figure 24As shown, after the distal bare stent segment 112 within the portal vein 83 is positioned, when it is necessary to adjust the length of the stent 10, the second binding wire 23 is pulled to disengage it from the gap 1013 between the male structure 1011 and the female structure 1012. Then, by pulling the pulling member 30, it is moved axially towards the proximal side, and the wave coil is moved towards the proximal side. On the one hand, the male structure 1011 is separated from the female structure 1012. On the other hand, the two wave coils connected by the male structure 1011 and the female structure 1012 are moved and extended axially to increase the axial length of the stent 10 until the length of the stent 10 reaches the length required to construct the shunt channel.

[0120] Furthermore, along the axial direction of the support 10, multiple wave coils are sequentially snapped together by male structure 1011 and female structure 1012, and the second binding wire 23 is sequentially clamped between multiple male structures 1011 and female structures 1012.

[0121] In this embodiment, when the stent 10 is fully released and the second binding wire 23 is in a bound state, the proximal bare stent segment 111 is not finally positioned in the hepatic vein 81. After the second binding wire 23 is released, it disengages from the gap 1013 between all the male structures 1011 and female structures 1012, allowing the male structures 1011 and female structures 1012 between each wave loop to disengage under the pulling action of the pulling member 30. Therefore, after the second binding wire 23 is released, the physician can observe whether the length of the proximal bare stent segment 111 in the hepatic vein 81 is appropriate, and by pulling the proximal end of the pulling member 30, at least some of the male structures 1011 and female structures 1012 of the wave loops are disengaged, so that some wave loops are in an overlapping state and other wave loops are in an extended state, so that the axial length of the proximal bare stent segment 111 is adapted to the hepatic vein 81, or the axial length of the covered segment 113 is adapted to the length of the liver parenchyma 82.

[0122] It should be noted that, in actual use, the required length of the stent 10 varies depending on the size of the liver and the puncture channel used by each individual. However, current technology considers the portal vein 83 end to be of a fixed length, requiring no adjustment. The adjustment is needed for the length of the remaining covered segment 113 within the liver parenchyma 82 and the proximal bare stent segment 111 within the hepatic vein 81. Therefore, the coils bound by the restraints in embodiments 3, 4, and 5 of this invention can be coils in the proximal bare stent segment 111 or the covered segment 113. Alternatively, the restraints can be used to bind the coils in the proximal bare stent segment 111 and the covered segment 113 respectively, to facilitate adjustment of the axial lengths of the proximal bare stent segment 111 and the covered segment 113. It is understood that, in other embodiments, the distal bare stent segment 112 at the portal vein 83 end can also be adjusted according to embodiments of this invention.

[0123] Example 6

[0124] According to embodiments of the present invention, such as Figure 21 As shown, a conveying system 600 is also proposed, which includes a support system 100, a sheath core 61 and an outer sheath 62.

[0125] Specifically, please combine Figure 21 , Figure 22 , Figure 23 and Figure 24 As shown, in the support system 100, the support 10 is sleeved outside the sheath core 61, and the outer sheath 62 is sleeved outside the sheath core 61 and the support 10.

[0126] The outer sheath 62 is used to restrain the stent 10 in the stent system 100. By setting different inner diameters, the outer sheath 62 can restrict the outer diameter of the nickel-titanium stent 10 to the required range, allowing it to pass through the vascular sheath during actual surgery. The outer sheath 62 can be made of a single-layer common polymer material such as nylon elastomer (Pebax) or nylon. Alternatively, the outer sheath 62 can be made of a composite tubing, for example, using PTFE as the inner layer, stainless steel braided mesh as the middle layer, and Pebax as the outer layer. Fusing these three layers through hot pressing yields an outer sheath with better support performance.

[0127] The sheath core 61 serves to fix the position of the stent 10, preventing it from shortening or shifting during deployment, and to expand the stainless steel portion of the stent 10. The sheath core 61 includes a smoothly tapered tip 611, a double-lumen tube 612, an anti-shortening block 613, a limiting block 614, a balloon 615, and a connector 616. The smoothly tapered tip 611 prevents damage to the vessel wall during the delivery system 600's movement. The double-lumen tube 612 serves as a first lumen 617 for guiding the guidewire and a second lumen 618 for injecting fluid into the balloon to create pressure and open it. Holes 619 are evenly distributed inside the balloon and within the double-lumen tube, allowing fluid from the second lumen 618 to be evenly released into the balloon. There are at least two holes, located at both ends of the balloon, and possibly three or more, evenly distributed in the middle of the balloon. The anti-shortening block 613 and the limiting block 614 prevent the stent 10 from shortening and shifting during the retraction of the outer sheath. The anti-shortening block 613 and the limiting block 614 are made of polymer or metal materials and are glued to the surface of the double-lumen tube. A balloon, made of nylon or Pebax, is used to expand the stainless steel stent portion of the covered section 113 using liquid pressure. The balloon's diameter is the same as that of the stainless steel stent 10. Because the two ends of the balloon are to be connected to the smaller-diameter double-lumen tube via thermal welding, the length of the balloon is greater than the length of the covered section 113 stent, ranging from 1mm to 3mm. This ensures that the impact on the proximal bare stent end 111 and the distal bare stent section 112 of the nickel-titanium portion is minimized.

[0128] During the procedure, the stent system 100 is pre-loaded onto the sheath core 61 and secured within the outer sheath 62. An anti-shortening block 613 is located inside the proximal bare stent segment 111, a balloon is located inside the covered segment 113 stent, and a limiting block 614 is located on one side of the proximal end of the entire stent 10. Figure 24As shown, after establishing the channel, the entire stent system is first delivered to the lesion site. The distal bare stent segment 112 should extend beyond the liver parenchyma 82 and enter the portal vein 83. When the covered segment 113, observed by DSA, has slightly extended beyond the liver parenchyma 82 to 1-3 mm, the outer sheath 62 is withdrawn until it is flush with the distal end of the covered segment 113, allowing the nickel-titanium segment of the distal bare stent segment 112 to expand first. Then, the entire delivery system 600 is slightly withdrawn, and when the stent 10 contacts the liver parenchyma, a noticeable resistance to withdrawal is felt, ensuring that the distal end of the covered segment 113 is flush with the distal end of the liver parenchyma 82. The outer sheath is then withdrawn further, allowing all nickel-titanium segment stents (i.e., the proximal bare stent segment 111 and the distal bare stent segment 112) to expand into the vessel. Finally, the intermediate stainless steel segment stent 10 (i.e., the covered segment 113) is deployed by pressurizing the water injection channel on the connector to the required pressure using a pressure pump. If the pressure reduction in portal vein 83 is insufficient at this point, the entire delivery system 600 can be withdrawn, and a balloon of appropriate diameter can be reinserted to further expand the covered segment 113 stent, increasing its diameter and thus further reducing pressure. Specifically, the distal bare stent segment 112 is the portion of stent 10 located at the portal vein 83 end, the covered segment 113 is the portion of stent 10 located in the liver parenchyma 82, and the proximal bare stent segment is the portion of stent 10 located in the hepatic vein 81.

[0129] Example 7

[0130] like Figure 25 and Figure 26 As shown, this embodiment provides a stent structure that enables precise positioning of the stent 10 during deployment. Existing technology can only locate the stent by visually comparing the contrast strips or points 13 set on the covered segment 113 and the bare stent segment under digital subtraction angiography (DSA) and assisting with the resistance of stent retraction to ensure the covered segment 113 completely covers the liver parenchyma 82 segment. This visual comparison is limited by the three-dimensional characteristics of human anatomy; under DSA, only a planar surface can be observed, which can cause certain errors, resulting in deviations in the positioning.

[0131] Therefore, this embodiment provides a stent 10 with a barbed structure. The stent has a barbed structure between the bare stent segment and the covered stent segment. That is, a barbed structure is provided at the junction of the covered segment 113 and the proximal bare stent segment 111, and / or a barbed structure is provided at the junction of the covered segment 113 and the distal bare stent segment 112.

[0132] The barb 711 is also made of nickel-titanium material, and its shape is initially positioned in an open state through heat setting. When the outer sheath is retracted, the barb is in a tightened shape. Referring to Example 6, during release, the delivery system 600 is now simply inserted a certain distance into the portal vein 83, and angiography shows that the distal bare stent segment 112 is completely located within the portal vein 83. Then the outer sheath can be withdrawn without comparing the position of the withdrawn outer sheath with DSA. When the barb is released from the outer sheath, the operator will clearly feel a decrease in the resistance to withdrawal within the portal vein 83. Continue withdrawing the delivery system 600 until there is significant resistance, that is, the barb is embedded in the liver parenchyma 82. The stent positioning at the portal vein 83 end is then completed. Subsequent steps are consistent with Example 6. In order to maintain the effectiveness of fixation and the complex three-dimensional situation in the body, barbs can be provided at each wavy protrusion (peak or trough) at the junction of the covered segment 113 and the proximal bare stent segment 111 and the distal bare stent segment 112. In other embodiments, at least one barb may be provided at the junction of the covered segment 113 with the proximal bare stent segment 111 and the distal bare stent segment 112.

[0133] Please combine Figure 26 and Figure 27 As shown, to improve anchoring efficiency, the angle between the barb 711 and the outer circumferential surface of the bracket 10 is between 30 and 45 degrees, and the axial length h of the barb along the bracket 10 does not exceed one-third of the height of the corrugation of that section of the support body 11. Figure 28 As shown, the barbs can also be designed with a tapered shape to facilitate easier insertion into the tissue for anchoring. To make the support 10 more securely fixed in the body, the barbs can also be located at the junction of the liver parenchyma and the hepatic vein 713 and at the opening of the hepatic vein 714.

[0134] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A support system, characterized in that, include: The support includes multiple wave coils; A restraint member is connected to at least two of the wave coils. The restraint member has a restrained state and a released state. In the restrained state, the restraint member causes the wave coils connected to it to overlap axially or shorten the axial distance between them and fixes them. In the released state, the wave coils connected to the restraint member are released from fixation. A traction member is connected to the bracket. In the released state, the axially overlapping wave coils have an axially overlapping length. Pulling the traction member can shorten or eliminate the axially overlapping length, or pull the traction member can increase the axial distance between the wave coils connected to the restraint member.

2. The support system according to claim 1, characterized in that, The restraint member includes a first restraint wire. In the restrained state, the first restraint wire is wound around at least two of the wave loops and applies a converging restraint force to the at least two wave loops along the axial direction of the bracket, so that the at least two wave loops overlap axially or shorten the axial distance, and are then fixed.

3. The support system according to claim 2, characterized in that, The first binding wire is sequentially wound around multiple peaks and / or troughs of the at least two wave loops along the circumference of the support, and in the bound state, a binding force is applied to the at least two wave loops along the circumference of the support in a radial direction toward the support, so that the diameter of the at least two wave loops in the bound state becomes smaller.

4. The support system according to claim 2, characterized in that, The support system includes a plurality of first binding wires spaced apart along the axial direction of the support.

5. The support system according to claim 1, characterized in that, The restraint member includes an elastic connector, the two ends of which are respectively connected to two adjacent wave coils; In the constrained state, along the radial direction of the support, the elastic connector and the two wave coils at least partially connected to the elastic connector overlap and are fixed together; Pulling the traction member puts the elastic connector in the released state. In the released state, along the axial direction of the bracket, the elastic connector and the two wave coils connected to the elastic connector are arranged sequentially.

6. The support system according to claim 5, characterized in that, The support system includes a plurality of elastic connectors, with at least two elastic connectors forming a group. The elastic connectors in each group are arranged at intervals along the circumference of the support. Along the axial direction of the support, a plurality of corrugated coils are sequentially connected to the plurality of groups of elastic connectors.

7. The support system according to claim 1, characterized in that, Each of the two wave coils is provided with a male structure and a female structure that can be plugged in, and the male structure and the female structure have a gap when plugged in; The restraint member includes a second restraint wire. In the restrained state, the male structure is inserted into the female structure, and part of the second restraint wire is located between the male structure and the female structure and fills the gap, so that the male structure and the female structure are engaged. In the released state, the second restraint wire comes out from the gap, and then the pulling member is pulled to cause the male structure to be released from the female structure.

8. The support system according to claim 7, characterized in that, Along the axial direction of the bracket, multiple wave coils are sequentially snapped together by the male structure and the female structure, and the second binding wire is sequentially clamped between the multiple male structures and the female structure.

9. The support system according to any one of claims 1 to 8, characterized in that, The stent includes a covered segment, a proximal bare stent segment connected to the proximal end of the covered segment, and a distal bare stent segment connected to the distal end of the covered segment. The stent is provided with barbs, the barbs are provided at the junction of the covered segment and the proximal bare stent segment, and / or the barbs are provided at the junction of the covered segment and the distal bare stent segment.

10. A conveying system, characterized in that, The conveying system includes the support system as described in any one of claims 1 to 9, and the conveying system further includes: Sheath core, the support in the support system is sleeved on the outside of the sheath core; An outer sheath is fitted over the sheath core and the support.

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