Hybrid stent delivery system for central vein

Abstract

The invention relates to a hybridization stent conveying system for central veins. The hybridization stent conveying system comprises an outer sheath tube, a handle assembly, an inner sheath core, a pre-cutting tool, a hybridization stent and a tearable sleeve. The handle assembly comprises an outer shell and a transmission part, and the near end of the outer sheath tube penetrates through the outer shell in a sliding mode and is connected with the transmission part; the inner sheath core slidably penetrates through the outer sheath tube, and the near end of the inner sheath core is fixedly connected with the outer shell; the pre-cutting tool is arranged on the inner wall of the outer sheath tube; the intraoperative stent comprises an artificial blood vessel and an intravascular stent which are connected, and the intraoperative stent is arranged on the inner sheath core in a sleeving mode and located between the inner sheath core and the outer sheath tube after being compressed. The far end of the tearable cannula is fixedly connected with the inner wall of the outer sheath tube, and the tearable cannula is arranged on the periphery of the artificial blood vessel in a sleeving mode and constrains the artificial blood vessel after thermal shrinkage. When the transmission part drives the outer sheath tube to move towards the near end, the precutting tool cuts the tearable sleeve, and meanwhile the outer sheath tube drags the tearable sleeve to tear the tearable sleeve. According to the structure, the loading efficiency of loading the hybrid scaffold into the sheathing canal can be improved, and smooth release of the hybrid scaffold in a human body in a subsequent operation can also be ensured.

Description

Technical Field

[0001] This invention relates to the field of medical devices, and more specifically to a hybrid stent delivery system for central veins. Background Technology

[0002] During hemodialysis, arterial blood needs to be extracted to provide sufficient hemodynamics to drive the blood through the dialyzer. However, due to the difficulty and high risk of direct arterial puncture, arterial blood is usually indirectly obtained by connecting the artery and vein through an arteriovenous fistula (AVF) or arteriovenous graft (AVG, such as an artificial blood vessel). These connection methods allow the venous segment to withstand the pressure and flow of the artery, thus facilitating puncture and hemodialysis. In the process of establishing the vascular circuit for hemodialysis, hybrid surgery can quickly unblock central veins and replace venous vessels, and has wide applications in bypass and interventional procedures for central venous occlusive diseases.

[0003] Currently, in central venous hybrid surgery, a delivery system is typically used to transport hybrid stents (including interconnected vascular stents and artificial blood vessels) to the lesion area and release them to open the occluded segment of the central vein. Vascular stents, due to their metallic skeleton, possess a certain degree of axial rigidity and elastic recovery, thus exhibiting good accessibility and delivery performance. In contrast, artificial blood vessels are usually made of multi-layered PTFE membranes, which have poor elastic recovery and low axial stiffness, resulting in poor accessibility and maneuverability, and are prone to stacking during insertion into the sheath. Summary of the Invention

[0004] The purpose of this invention is to provide a hybrid stent delivery system for central veins during surgery, in order to solve the problems of poor accessibility and maneuverability of artificial blood vessels in the prior art.

[0005] This invention provides a hybrid stent delivery system for central veins, comprising: The outer sheath extends axially; The handle assembly includes a housing and a transmission component, wherein the proximal end of the outer sheath slides through the housing and is connected to the transmission component; The inner sheath core is slidably inserted into the outer sheath tube and its proximal end is fixedly connected to the outer shell. A pre-cutting tool is fixedly mounted on the inner wall of the outer sheath tube; A hybrid stent, comprising an interconnected artificial blood vessel and a vascular stent, is fitted onto the inner sheath core and, when compressed, is located between the inner sheath core and the outer sheath tube; A tearable sleeve is fixedly connected at its distal end to the inner wall of the outer sheath. It is sleeved around the periphery of the artificial blood vessel and, after heat shrinking, binds the artificial blood vessel. When the transmission component moves the outer sheath tube to the proximal end, the pre-cutting tool cuts the tearable sleeve while the outer sheath tube is pulled and torn.

[0006] The hybridization scaffold delivery system provided by this invention may also have the following additional technical features: In some specific embodiments of the present invention, the transmission component includes a pull wire and a sliding button, the sliding button being slidably disposed on the outer casing, one end of the pull wire being connected to the outer sheath tube, and the other end being connected to the sliding button.

[0007] In some specific embodiments of the present invention, a traction ring is fixed to the proximal end of the outer sheath tube, and there are two traction wires. The distal ends of the two traction wires are connected to the traction ring, and the connection positions are arranged radially opposite to the traction ring.

[0008] In some specific embodiments of the present invention, the transmission component further includes a winding column and a pulley. The winding column is fixed to the far end of the outer shell, the pulley is slidably disposed inside the shell and fixedly connected to the sliding button, and the proximal end of the drawing wire passes around the pulley and is tied to the winding column.

[0009] In some specific embodiments of the present invention, the outer casing is provided with a strip-shaped groove extending along the axial direction, the slider includes a slider body and a connecting rod, the slider body is located outside the outer casing, and the connecting rod passes through the strip-shaped groove and is fixedly connected to the pulley.

[0010] In some specific embodiments of the present invention, along the axial direction, a limiting platform is provided inside the outer shell, and the side of the pulley along the axial direction is adapted to and abuts against the limiting platform.

[0011] In some specific embodiments of the present invention, the pre-cutting tool includes a plurality of pre-cutting blades arranged circumferentially along the outer sheath tube, and the cutting edges of the plurality of pre-cutting blades are all arranged toward the central axis of the outer sheath tube.

[0012] In some specific embodiments of the present invention, the distal end of the tearable sleeve is further provided with a plurality of connecting pieces that are connected to the inner wall of the outer sheath tube, and the connecting pieces are offset from the pre-cutting blade in the circumferential direction.

[0013] In some specific embodiments of the present invention, there are two pre-cutting blades and two connecting pieces, each arranged radially opposite to the outer sheath tube, and the line connecting the two connecting pieces is perpendicular to the line connecting the two pre-cutting blades.

[0014] In some specific embodiments of the present invention, the pre-cutting blade has a rounded corner on the side facing the tearable sleeve.

[0015] The hybrid stent delivery system provided by this invention improves the accessibility and maneuverability of the artificial blood vessel by using a tearable sheath to restrain it during the loading process. Furthermore, this embodiment incorporates a pre-cutting tool within the outer sheath that moves with it to cut the tearable sheath, ensuring proper release of the artificial blood vessel. Therefore, this delivery system, while improving the loading efficiency of the hybrid stent outside the human body, also ensures smooth release of the stent within the body, thus enhancing surgical efficiency and reducing surgical risks. Attached Figure Description

[0016] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0017] Figure 1 This is a three-dimensional structural diagram of the hybridization scaffold delivery system in an embodiment of the present invention; Figures 2-3 This is a schematic cross-sectional view of two longitudinal sections arranged at 90° in the conveying state of an embodiment of the present invention; Figure 4 This is a cross-sectional schematic diagram of the longitudinal section of the conveying component in the released state in an embodiment of the present invention; Figure 5 This is a structural diagram of the inner sheath core and tearable sleeve components in an embodiment of the present invention; Figure 6 This is a partial structural schematic diagram of the hybridization scaffold delivery system in an embodiment of the present invention; Figure 7 This is a schematic diagram of the handle assembly of the hybridization scaffold delivery system in an embodiment of the present invention; Figure 8 for Figure 7 Enlarged view of the structure of part A in the middle.

[0018] Explanation of reference numerals in the attached figures: 1- Hybrid scaffold delivery system; 100 - Conveyor assembly; 200 - Handle assembly; 101-Hook, 102-Outer sheath, 103-Tearable cannula, 104-Artificial blood vessel, 105-Inner sheath core, 106-Pre-cutting tool, 107-Vascular stent, 108-End, 109-Traction ring, 110-Connecting piece; 201-Pulley, 202-Pulling wire, 203-Outer shell, 204-Sliding button, 205-Stress buffer tube, 206-Wound column, 207-Strip groove, 208-Limiting platform. Detailed Implementation

[0019] 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.

[0020] 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.

[0021] 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.

[0022] 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 is flipped, an element described as "below other elements or features" or "below other elements or features" would subsequently be oriented as "above other elements or features" or "above other elements or features." Therefore, the example term "below" can include both upper and lower orientations. The device may be otherwise oriented (rotated 90 degrees or in other directions), and the spatial relative descriptors used in the text will be interpreted accordingly.

[0023] To more clearly describe the structure of this application, the terms "proximal" and "distal" are used herein as conventional terms in the field of interventional medicine. Specifically, "distal" refers to the end furthest from the operator during the surgical procedure, "proximal" refers to the end closest to the operator during the surgical procedure, "axial" refers to its length direction, and "radial" refers to the direction perpendicular to the "axial".

[0024] Please see Figure 1 The hybrid stent delivery system 1 includes a delivery assembly 100 for delivering and releasing the hybrid stent and a handle assembly 200 for gripping and manipulating.

[0025] See Figure 2 As shown, in this invention, a hybrid stent refers to a stent assembly comprising a vascular stent 107 and an artificial blood vessel 104. In this embodiment, the vascular stent 107 can be a covered stent or a bare stent. A covered stent refers to an intravascular stent formed by covering a metal stent (e.g., nickel-titanium alloy) with a blood flow-isolating material. The blood flow-isolating material can be a biocompatible material such as PTFE or PET. The artificial blood vessel 104 refers to a flexible tubular stent made using multiple layers of blood flow-isolating materials, such as PTFE or PET, which are biocompatible. In this embodiment, the distal end of the artificial blood vessel 104 is fixedly connected to the proximal end of the vascular stent 107 by sutures or other methods, and the artificial blood vessel 104 and the vascular stent 107 together define a channel for blood flow.

[0026] See Figure 2-3As shown, the delivery assembly 100 includes an inner sheath core 105, an outer sheath tube 102, a pre-cutting blade 106, and a tearable sleeve 103. The inner sheath core 105 can be made of nickel-titanium alloy, stainless steel, or other metallic materials, and the lumen of the inner sheath core 105 allows the guide wire to pass through. Of course, in other embodiments, the material of the inner sheath core 105 can also be a polymer material, such as PI, PEEK, etc. The distal end of the inner sheath core 105 is connected to a tip 108, which is generally formed into a cylindrical structure, and the distal end is formed into a spherical or conical shape. The distal end of the inner sheath core 105 is also provided with a hook 101, which is located proximally to the end 108. A portion of the axial area between the proximal end of the hook 101 and the proximal end of the inner sheath core forms a loading area for the hybrid stent. The bare wave coil at the end of the vascular stent 107 can be hooked onto the hook 101, thus axially limiting the hybrid stent and confining it within the loading area to prevent displacement during delivery. The outer sheath tube 102 is slidably fitted over the inner sheath core 105, and its inner wall is provided with a pre-cutting tool 106. When the outer sheath tube 102 slides toward the distal end of the inner sheath core 105 until it abuts against the proximal end of the end 108, the loading area is closed.

[0027] After the hybrid stent is loaded into the sheath, the distal end of the tearable sleeve 103 is fixedly connected to the inner wall of the sheath. Once the tearable sleeve 103 is fixedly connected to the sheath, the pre-cutting tool 106 is inserted into the outer sheath along the gap between the vascular stent 107 and the outer sheath 102, and the inner wall of the outer sheath 102 is fixedly connected. To facilitate subsequent cutting of the tearable sleeve 103 by the pre-cutting tool 106, the proximal end of the pre-cutting tool 106 is closer to the distal end of the tearable sleeve 103. As the outer sheath 102 slides proximally, the pre-cutting blade 106 moves proximally along with the outer sheath 102, thereby cutting open the tearable sleeve 103. Since the tearable sleeve 103 is connected to the outer sheath 102, the outer sheath 102 can tear open the tearable sleeve 103 as it moves, thus releasing the confinement of the artificial blood vessel 104. As the outer sheath 102 is completely displaced from the loading area, the vascular stent 107 and the artificial blood vessel 104 can radially self-expand and be released into the blood vessel. Alternatively, the pre-cutting blade 106 can be fixed to the inner wall of the sheath first, and then the tearable sleeve can be fixed to the inner wall of the sheath.

[0028] The pre-cutting tool 106, the tearable sheath 103, and the inner wall of the sheath can be fixed by means of bonding, heat fusion, or welding. For example, adhesive can be injected into a specific location on the inner wall of the sheath using a needle to achieve bonding, or welding can be achieved by inserting a long strip welding rod with a welding head at the end into the sheath. There are no restrictions on the specific fixing method, as long as the pre-cutting tool is installed into the sheath after the artificial blood vessel has been loaded into the sheath.

[0029] When a hybrid stent is needed, the outer sheath 102 is first retracted so that the inner sheath core 105 is exposed outside the outer sheath 102. Then, the hybrid stent is fitted onto the inner sheath core 105, and the bare wave loop of the vascular stent 107 is hooked onto the hook 101 so that the vascular stent 107 is close to the distal end of the inner sheath core 105, and the artificial blood vessel 104 is close to the proximal end of the inner sheath core 105. Next, a tearable sleeve 103 is fitted onto the artificial blood vessel 104, and heating causes the tearable sleeve 103 to contract and bind to the outside of the artificial blood vessel 104, compressing the external dimensions of the artificial blood vessel 104 to be smaller than the inner diameter of the outer sheath 102. The tearable sleeve 103 can be made of a soft, easily torn polymer material such as polyolefin, which has high heat-melting shrinkage properties, allowing its size to be reduced by heating.

[0030] In this embodiment, after the tearable sheath 103 is fitted onto the artificial blood vessel 104, semi-fixation is achieved through heating. In this application, semi-fixation means that the tearable sheath 103 is merely heat-melted and shrunk before being fitted onto the outside of the artificial blood vessel 104 to bind it, but the two are not bonded together. Then, the handle assembly 200 is operated to move the outer sheath 102 distally. Since the outer diameter of the artificial blood vessel 104 is compressed to be smaller than or close to the inner diameter of the outer sheath 102, it can smoothly enter the outer sheath 102. For the vascular stent, it can be compressed to gradually enter the outer sheath 102. The assembled state can be referred to... Figures 6-7 .

[0031] In this embodiment, the artificial blood vessel 104 is compressed by the heat shrinking of the tearable sleeve 103. On the one hand, the axial stiffness of the artificial blood vessel 104 with the tearable sleeve 103 is increased; on the other hand, since the entire artificial blood vessel 104 can be compressed simultaneously along the circumference and the entire axial direction by the tearable sleeve 103 on its outer side, and is covered by the tearable sleeve 103 after compression, the artificial blood vessel 104 can be pushed into the smaller outer sheath 102. During the pushing process, the axial friction force it experiences is greatly reduced, preventing stacking during the pushing process into the outer sheath 102. Through the above settings, not only can the problems of poor pushability and accessibility caused by the low axial stiffness and easy stacking of the artificial blood vessel 104 be solved, but the size requirements of the outer sheath 102 can also be reduced, the size of the outer sheath 102 required for entry into the human body can be reduced, the delivery efficiency can be improved, and the volume of the handle assembly 200 that cooperates with the outer sheath 102 can be reduced simultaneously, making it easier for the operator to hold and operate.

[0032] See Figure 4As shown, when the hybrid stent needs to be released, the operable handle 200 causes the outer sheath 102 to retract. On the one hand, the vascular stent 107 will gradually be exposed outside the outer sheath 102 and then recover its deformation, thereby the vascular stent 107 will be gradually released. On the other hand, as the outer sheath 102 retracts, the pre-cutting blade 106 cuts the tearable sleeve 103 while the outer sheath 102 pulls on it, causing it to tear, thereby releasing the tearable sleeve 103 from the restraint of the artificial blood vessel 104, thereby realizing the release of the artificial blood vessel 104.

[0033] In this embodiment, the pre-cutting blade 106 only pre-cuts the tearable sleeve 103 without completely cutting it, thereby avoiding damage to the artificial blood vessel 104 located inside the tearable sleeve 103 during the cutting process. In this application, pre-cutting refers to the pre-cutting blade 106 creating scratches on the outer surface of the tearable sleeve 103 during the cutting process, without completely cutting it open. Because the pre-cutting blade 106 has pre-cut the tearable sleeve 103, it will tear along the pre-cut scratches during the pulling process.

[0034] Therefore, the hybrid stent delivery system 1 provided in this embodiment of the invention improves the access performance and pushability of the hybrid stent by using a tearable sheath 103 to restrain the artificial blood vessel 104 during the loading step. Furthermore, this embodiment also achieves normal release of the artificial blood vessel 104 by providing a pre-cutting blade 106 within the outer sheath 102 that moves with the outer sheath 102 to cut the tearable sheath 103. Thus, the delivery system in this embodiment improves the loading efficiency of the hybrid stent outside the human body while ensuring smooth subsequent release of the hybrid stent inside the human body, thereby improving surgical efficiency and reducing surgical risks.

[0035] Please refer to Figure 5 In some embodiments, the pre-cutting blade 106 includes a plurality of pre-cutting blades arranged circumferentially along the outer sheath 102, with the cutting edges of the plurality of pre-cutting blades all facing the central axis of the outer sheath 102. The distal end of the tearable sleeve 103 is also provided with a plurality of connecting pieces 110, which are offset from the pre-cutting blade 106 and are used to connect with the outer sheath 102.

[0036] Specifically, the pre-cutting blade is roughly rectangular in shape and is disposed on the inner wall of the outer sheath 102 along the axial direction of the outer sheath 102, with the cutting edge facing the central axis of the outer sheath 102. There are multiple pre-cutting blades, such as 2, 3, or 4. Preferably, there are two pre-cutting blades, which are evenly spaced along the circumference of the outer sheath 102.

[0037] This embodiment uses multiple pre-cutting blades spaced circumferentially along the outer sheath 102 to cut the tearable sleeve 103, thus enabling the artificial blood vessel 104 to be bound by the tearable sleeve 103. This not only solves the problems of poor accessibility and stacking caused by the poor elastic recovery and low axial stiffness of the artificial blood vessel 104, but also facilitates the assembly of the outer sheath 102. Furthermore, it reduces the compression diameter of the artificial blood vessel 104, thereby reducing the diameter requirement of the outer sheath 102 and improving the flexibility and operability of the delivery assembly 100.

[0038] Multiple connecting tabs 110 are spaced apart circumferentially along the distal end of the tearable sleeve 103. After the tearable sleeve 103 is loaded into the outer sheath 102, the connecting tabs 110 can be used to bond or weld the tearable sleeve 103 to the inner wall of the outer sheath 102, thus connecting the tearable sleeve 103 and the outer sheath 102. Since the tearable sleeve 103 and the outer sheath 102 are connected, when the outer sheath 102 moves axially proximally under drive, it can move the connecting tabs 110, thereby detaching the cut tearable sleeve 103 from the artificial blood vessel 104, releasing the artificial blood vessel 104.

[0039] See Figure 5 For example, there are two connecting pieces 110, and they are offset from the pre-cutting blade 106 in the circumferential direction of the outer sheath 102. The pre-cutting blade 106 is disposed between two adjacent connecting pieces 110. That is, there are two pre-cutting blades and two connecting pieces 110, and each is arranged opposite to the other in the radial direction of the outer sheath 102. The line connecting the two connecting pieces 110 is perpendicular to the line connecting the two pre-cutting blades. Thus, the cut formed by the pre-cutting blade is located between the two connecting pieces 110, and the force generated by the two connecting pieces 110 moving with the outer sheath 102 can be directly applied to the cut to facilitate tearing the tearable sleeve 103.

[0040] By setting the line connecting the two connecting pieces 110 perpendicular to the line connecting the two pre-cutting blades, on the one hand, the two radially opposite pre-cutting blades cut the tearable sleeve 103 to pre-cut it into two semi-circular rings (two semi-circular rings in cross-section). On the other hand, the connecting pieces 110, which are at a 90-degree angle to the pre-cutting blades in the circumferential direction, will pull the two semi-circles under the action of the outer sheath tube 102, thereby causing the two semi-circular rings of the tearable sleeve 103 to be torn apart and separated from each other.

[0041] Please continue to refer to Figure 4As shown, in some embodiments, the proximal end of the pre-cutting blade of the pre-cutting cutter 106 is rounded. This rounded corner increases the contact area between the pre-cutting blade and the end of the tearable sleeve 103, achieving a smooth transition and ensuring a good entry point when the cutting edge of the pre-cutting blade contacts the proximal side of the tearable sleeve. This avoids interference between the end of the pre-cutting blade and the tearable sleeve 103, thus facilitating the cutting of the tearable sleeve 103 by the pre-cutting blade.

[0042] Please refer to Figure 1 , 6 As shown in Figure 7, the handle assembly 200 includes a housing 203 and a transmission component. The proximal end of the outer sheath 102 slides through the housing 203 and is connected to the transmission component, and can move proximally under the drive of the transmission component. The housing 203 forms the main structure of the handle assembly 200, is fixedly connected to the proximal end of the inner sheath core 105, and is mainly used for the operator to hold. The transmission component is connected to the housing 203 and can move axially relative to the housing 203. The proximal end of the outer sheath 102 slides through the distal end of the housing 203, and its proximal end is connected to the transmission component. Thus, the outer sheath 102 can be linked with the transmission component, and the transmission component can drive the outer sheath 102 to move proximally, thereby realizing the cutting and peeling of the tearable sheath 103 and the release of the vascular stent 107 and artificial blood vessel 104. The present invention, through the above-described configuration, facilitates the operator's delivery and release operations of the delivery component 100, thereby promoting the smooth progress of the surgery.

[0043] Please refer to Figure 6-7 In some embodiments, the transmission component includes a pull wire 202 and a slider 204. The slider 204 is slidably disposed on the outer casing 203. One end of the pull wire 202 is connected to the outer sheath tube 102, and the other end is connected to the slider 204.

[0044] Specifically, the distal end of the traction wire 202 is connected to the outer sheath 102, and the other end extends from the distal end of the outer shell 203 into the outer shell 203 and is connected to the sliding button 204 slidably connected to the outer shell 203. This realizes the linkage between the transmission component and the outer sheath 102, and then the transmission component can drive the outer sheath 102 to move proximally, thereby realizing the cutting and peeling of the tearable sleeve 103 and the release of the vascular stent 107 and artificial blood vessel 104.

[0045] Please refer to Figure 8 In some embodiments, a traction ring 109 is provided at the proximal end of the outer sheath 102, and there are two traction wires 202. The distal ends of the two traction wires 202 are connected to the traction ring 109, and the connection positions are radially opposite to the traction ring 109.

[0046] Specifically, the outer diameter of the traction ring 109 is approximately the same as the inner diameter of the outer sheath 102, and it is specifically fixed to the inner wall of the outer sheath 102. It can also be used to connect the outer sheath 102 and the pulling wire 202. The distal end of the pulling wire 202 can be wrapped around the traction ring 109 and tied to it. Alternatively, the position of the pulling wire 202 can be defined by providing a perforation in the traction ring 109 and tying the distal end of the pulling wire 202 into the perforation. Of course, the traction ring 109 and the pulling wire 202 can also be connected by bonding.

[0047] Furthermore, there are two traction wires 202, the distal ends of which are connected to the traction ring 109, and the connection positions are at both ends of a diameter of the traction ring 109. In this way, the outer sheath 102 will have two roughly symmetrically arranged force points, thereby keeping the outer sheath 102 balanced throughout the driving process, avoiding damage to the artificial blood vessel 104 by the preset cutter 106, and thus improving the reliability of delivery.

[0048] It should be noted that in other embodiments, the pulling wire 202 can also be directly connected to the outer sheath tube 102, for example, by bonding the pulling wire 202 to the outer sheath tube 102, or by fastening the pulling wire 202 to the perforation at the proximal end of the outer sheath tube 102.

[0049] Please refer to Figure 6-7 In some embodiments, the transmission component further includes a winding post 206 and a pulley 201. The winding post 206 is fixed to the far end of the outer casing 203, and the pulley 201 is slidably disposed inside the outer casing 203 and fixedly connected to the sliding button 204. The proximal end of the drawing wire 202 passes around the pulley 201 and is tied to the winding post 206.

[0050] Specifically, the winding post 206 and the pulley 201 are both disposed within the inner cavity of the outer shell 203. The winding post 206, pulley 201, and drawing wire 202 combine to form a movable pulley structure. The sliding button 204 is connected to the pulley 201 and can slide along the axial direction of the outer shell 203 to drive the pulley 201 to slide. When the sliding button 204 drives the pulley 201 to slide axially towards the proximal end, it can drive the drawing wire 202 to move, thereby driving the outer sheath 102 to move towards the proximal end. Through the arrangement of this movable pulley 201 structure, the stroke of the drawing wire 202 is twice the stroke of the pulley 201, that is, the distance the outer sheath 102 moves towards the proximal end is twice the stroke of the sliding button 204. When the sliding button 204 slides a distance L towards the proximal end, the distance the outer sheath 102 slides towards the proximal end is 2L. This can help reduce the operating length of the handle assembly 200, thereby shortening the overall length of the handle assembly 200 and making it easier for the operator to hold and operate it.

[0051] Of course, in other embodiments, the drawing wire 202 can be directly connected to the sliding button 204 and pull the outer sheath 102 to move proximally as the sliding button 204 slides axially.

[0052] Please refer to Figure 6-7 In some embodiments, the outer casing 203 has an axially extending strip groove 207, and the slider 204 includes a slider body 2041 and a connecting rod 2042. The slider body 2041 is located outside the outer casing 203, and the connecting rod 2042 passes through the strip groove 207 and is fixedly connected to the pulley 201.

[0053] Specifically, the strip groove 207 is an elongated groove arranged along the axial direction of the outer casing 203. The sliding button 204 is provided corresponding to the strip groove 207. The sliding button body 2041 of the sliding button 204 protrudes from the outer side of the outer casing 203 and is suitable for easy pushing by the operator. The connecting rod 2042 passes through the strip groove 207, and one end is connected to the sliding button body 2041, and the other end is connected to the pulley 201. This realizes the linkage between the sliding button 204 and the pulley 201. In this way, the sliding button 204 can drive the pulley 201 to move, and the pulley 201 and the pulling wire 202 can drive the outer sheath 102.

[0054] Please refer to Figure 6-7 In some embodiments, the handle assembly 200 further includes a stress buffer tube 205, which is connected to the distal end of the outer shell 203 and sleeved on the outside of the inner sheath core 105 and the drawing wire 202.

[0055] Specifically, the stress buffer tube 205 has a diameter approximately larger than that of the outer sheath tube 102, and is inserted and fixed to the distal end of the outer casing 203. It also fits around the proximal ends of the outer sheath tube 102, the inner sheath core 105, and the drawing wire 202, allowing these components to extend distally through the stress buffer tube 205. It should be noted that the length of the stress buffer tube 205 should be such that the proximal end of the outer sheath tube 102 does not detach from the stress buffer tube 205 during the entire axial sliding process of the outer sheath tube 102 on the inner sheath core 105.

[0056] In this embodiment, by setting a stress buffer tube 205 and limiting the proximal end of the outer sheath tube 102 by the stress buffer tube 205, the smooth axial sliding of the outer sheath tube 102 can be ensured. At the same time, by using the stress buffer tube 205 to limit the outer sheath tube 102, the axial length of the outer shell 203 can be further reduced, thereby reducing the volume of the handle assembly 200.

[0057] Please refer to Figure 6-7 In some embodiments, a limiting platform 208 is provided on the two opposing inner sides of the outer shell 203 along the axial direction, and the two axial sides of the pulley 201 are adapted to abut against the limiting platform 208.

[0058] Specifically, for ease of subsequent assembly, in this embodiment, the outer shell 203 is divided into two parts, comprising a first shell and a second shell. The first shell and the second shell are fastened together to form an outer shell 203 with a receiving cavity. The overall structure of the first shell and the second shell in this embodiment is basically the same; therefore, no specific distinction is made between the first shell and the second shell, and they are collectively referred to as the outer shell 203, unless specifically described to emphasize the structural differences between the first shell and the second shell. Along the axial direction, both the first shell and the second shell have protruding limiting platforms 208. Each limiting platform 208 includes two axially extending protrusions, with a groove formed between the two protrusions. The width of this groove is smaller than the diameter of the pulley 201, and the distance between the limiting platforms 208 on the first shell and the second shell is approximately equal to the thickness of the pulley 201, thus achieving axial limiting of the pulley. Since the pulley 201 is connected to the sliding button 204, and the sliding button 204 is constrained by the strip groove 207, this achieves radial (perpendicular to the axial direction) limiting of the pulley 201 on the handle.

[0059] This embodiment improves the stability of pulley 201 through the above-described settings, thereby ensuring the reliability of the conveying.

[0060] Please refer to Figure 6 In some embodiments, the central axis of the stress buffer tube 205 is coaxial with the tangential direction of the pulley 201 in the corresponding direction. Thus, when the drawing wire is taut, it can directly enter the stress buffer tube 205 along the central axis without contacting and wearing against the tube wall at the axial end of the stress buffer tube 205. This reduces the loss of driving force and the wear on the stress buffer tube 205, thereby improving the reliability of the hybrid support delivery system 1.

[0061] The strip grooves 207 are two in number and arranged opposite to each other, located on the first housing and the second housing respectively. The strip grooves 207 are positioned in the middle of the limiting platform 208, allowing the sliding button 204 to be inserted into the limiting platform 208 through the strip grooves 207 and connected to the pulley 201. Since there are two sliding buttons 204, the operator can simultaneously apply force to the sliding buttons 204 to move the pulley 201, further balancing the forces on the pulley 201 and improving its stability.

[0062] In other embodiments, the transmission component may further include a slider and a sleeve, wherein the slider has an external thread and is fixedly connected to the proximal end of the outer sheath tube, and the slider is limited to being able to move only axially along the outer casing and cannot rotate, and the sleeve is rotatably fitted around the outer periphery of the outer casing and has an internal thread that engages with the external thread. Therefore, the slider can be driven to move relative to the outer casing by rotating the sleeve, thereby driving the outer sheath tube to move forward or backward relative to the outer casing.

[0063] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A hybrid stent delivery system for central veins, characterized in that, include: The outer sheath extends axially; The handle assembly includes a housing and a transmission component, wherein the proximal end of the outer sheath slides through the housing and is connected to the transmission component; The inner sheath core is slidably inserted into the outer sheath tube and its proximal end is fixedly connected to the outer shell. A pre-cutting tool is fixedly mounted on the inner wall of the outer sheath tube; A hybrid stent, comprising an interconnected artificial blood vessel and a vascular stent, is fitted onto the inner sheath core and, when compressed, is located between the inner sheath core and the outer sheath tube; A tearable sleeve is fixedly connected at its distal end to the inner wall of the outer sheath. It is sleeved around the periphery of the artificial blood vessel and, after heat shrinking, binds the artificial blood vessel. When the transmission component moves the outer sheath tube to the proximal end, the pre-cutting tool cuts the tearable sleeve while the outer sheath tube is pulled and torn.

2. The conveying system according to claim 1, characterized in that, The transmission component includes a pull wire and a sliding button. The sliding button is slidably disposed on the outer shell. One end of the pull wire is connected to the outer sheath tube, and the other end is connected to the sliding button.

3. The conveying system according to claim 2, characterized in that, The outer sheath is fixed with a traction ring at its proximal end. There are two traction wires, and the distal ends of the two traction wires are connected to the traction ring, with the connection positions being radially opposite to the traction ring.

4. The conveying system according to claim 2, characterized in that, The transmission component also includes a winding column and a pulley. The winding column is fixed to the far end of the outer shell, and the pulley is slidably disposed in the outer shell and fixedly connected to the sliding button. The proximal end of the drawing wire passes around the pulley and is tied to the winding column.

5. The conveying system according to claim 4, characterized in that, The outer casing has an axially extending groove. The slider includes a slider body and a connecting rod. The slider body is located outside the outer casing, and the connecting rod passes through the groove and is fixedly connected to the pulley.

6. The conveying system according to claim 4, characterized in that, Along the axial direction, the housing is provided with a limiting platform extending axially, and the side of the pulley along the axial direction is adapted to abut against the limiting platform.

7. The conveying system according to claim 1, characterized in that, The pre-cutting tool includes a plurality of pre-cutting blades arranged circumferentially along the outer sheath, and the cutting edges of the plurality of pre-cutting blades are all oriented toward the central axis of the outer sheath.

8. The conveying system according to claim 7, characterized in that, The distal end of the tearable sleeve is also provided with a plurality of connecting pieces that connect to the inner wall of the outer sheath tube, and the connecting pieces are offset from the pre-cutting blade in the circumferential direction.

9. The conveying system according to claim 8, characterized in that, The pre-cutting blade and the connecting piece are both two in number and are arranged opposite each other along the radial direction of the outer sheath. The line connecting the two connecting pieces is perpendicular to the line connecting the two pre-cutting blades.

10. The conveying system according to claim 7, characterized in that, The pre-cutting blade has a rounded corner on the side facing the tearable sleeve.

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