Stent delivery catheter

Abstract

This invention provides a stent delivery catheter, relating to the field of medical device technology, and solves the problem of easy kinking during stent delivery and release. At the distal end of the catheter body, an axially extending internal thread is provided on the lumen wall. A rotating sleeve engages with the internal thread through an external thread on its outer circumferential wall, allowing the rotating sleeve to be coaxially positioned within the lumen. The torsion of the stent transmits torque to the rotating sleeve. As the rotating sleeve rotates circumferentially relative to the catheter body, it moves distally, eliminating the torsional difference between the proximal and distal ends of the stent while simultaneously releasing the stent. This stent delivery catheter utilizes the torque generated by the stent's torsion, allowing the rotating sleeve to convert the obtained torque into the power for actively feeding and releasing the stent via the threaded engagement structure. This achieves the function of simultaneous active torque relief and assisted release, simplifying the stent delivery process and reducing operational complexity to a certain extent.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, specifically to a stent delivery catheter. Background Technology

[0002] The routine clinical delivery and deployment of endovascular stents (including intracranial, coronary, and peripheral stents) and other cavity stents all rely on catheter-based access. In related technologies, catheters used for stent delivery are mostly made of rigid or semi-rigid materials, with a single, integrated cavity design, and their tips are strictly coaxial. These catheters achieve stable support of the stent through the friction between their inner wall and the stent, preventing stent detachment during delivery and enabling axial pushing and retraction.

[0003] Because human blood vessels or other cavities have natural tortuosity, bifurcation, and rotation angles, complications such as stent kinking and poor opening can easily occur during the delivery and release of stents through catheters. Summary of the Invention

[0004] The purpose of this invention is to design a stent delivery conduit to solve the problem of easy kinking during stent delivery and release.

[0005] This invention is achieved through the following technical solution: Some embodiments of the present invention provide a stent delivery conduit, comprising a tube body and a rotating sleeve; the tube body extends axially from a proximal end to a distal end, and an axially penetrating lumen is provided on the inner side of the tube body; at the distal end of the tube body, the lumen wall is provided with an axially extending internal thread; the rotating sleeve is coaxially disposed with the tube body, and an axially penetrating delivery channel is provided on the inner side of the rotating sleeve, the inner peripheral wall of the delivery channel being used to radially contact and compress the outer peripheral surface of the stent placed therein; the outer peripheral of the rotating sleeve is provided with an external thread, and the rotating sleeve is disposed in the lumen and engages with the internal thread through the external thread, so that the rotating sleeve can rotate relative to the tube body under the circumferential driving action of the stent.

[0006] With the above-described structure, a rotating sleeve located within the tube cavity is threaded at the distal end of the tube, forming a two-layer rotatable structure. This allows the rotating sleeve to rotate circumferentially and move axially within the tube under tangential external force. The inner circumferential wall of the rotating sleeve radially contacts and compresses the outer circumferential surface of the stent. The friction between the rotating sleeve and the stent provides reliable constraint on the inserted stent, ensuring smooth transport in tortuous or narrow body cavities, avoiding the risk of stent detachment, and guaranteeing transport safety. Thus, when the distal end of the stent is pushed out by the pushing mechanism and anchored in the body cavity, a torsional difference between the proximal and distal ends of the stent occurs due to the torsion of the body cavity. The proximal end of the stent in contact with the rotating sleeve transmits torque to the rotating sleeve, causing it to overcome its rotational resistance and rotate circumferentially relative to the tube, thereby alleviating or even eliminating the torsional difference between the proximal and distal ends and effectively preventing the stent from twisting during transport and release. Simultaneously, as the rotating sleeve rotates circumferentially relative to the tube, it moves towards the distal end to release the stent while simultaneously eliminating the torsional difference between the proximal and distal ends. This allows the stent delivery conduit to utilize the torque generated by the stent's torsion, enabling the rotating sleeve to convert the obtained torque into the power for actively feeding and releasing the stent through the threaded meshing structure. This achieves the function of simultaneously unloading torque and assisting in release, which can simplify the stent delivery process and reduce operational complexity to a certain extent.

[0007] To further improve the implementation of the present invention, the following configuration is adopted: the delivery channel is coaxially arranged with the cavity.

[0008] To further improve the implementation of the present invention, the following configuration is adopted: the diameter of the conveying channel is smaller than the diameter of the cavity.

[0009] To further improve the implementation of the present invention, the following structure is specifically adopted: the rotating sleeve is self-locking through the engagement of the external thread and the internal thread.

[0010] When the above-mentioned structure is adopted, the threaded engagement between the rotating sleeve and the tube body has self-locking properties, which can effectively prevent the rotating sleeve from rotating due to the axial movement of the support relative to the rotating sleeve, thereby avoiding premature release of the support or undesirable torsion of the support, making the release process of the support more controllable.

[0011] To further improve the implementation of this invention, the following structure is specifically adopted: the axial length of the rotating sleeve is less than the axial length of the bracket.

[0012] To further improve the implementation of the present invention, the following configuration is adopted: the axial length of the internal thread is less than or equal to the axial length of the bracket.

[0013] To further improve the implementation of the present invention, the following configuration is adopted: the axial distance between the distal end of the internal thread and the distal end face of the tube body is less than or equal to 1.2 mm.

[0014] To further improve the implementation of the present invention, the following structure is specifically adopted: the inner peripheral wall of the rotating sleeve is provided with a hydrophilic or hydrophobic coating.

[0015] When the above-mentioned structure is adopted, the inner peripheral wall of the rotating sleeve can effectively avoid thrombosis by providing a hydrophilic or hydrophobic coating.

[0016] To further improve the present invention, the following structure is adopted: a developing section with developing properties is provided at the distal end of the tube body, the developing section is circumferentially closed around the tube body, the axial distance between the developing section and the distal end face of the tube body is 0.6mm-1.2mm, and the axial length of the developing section is 0.8mm-1.2mm.

[0017] To further improve the implementation of this invention, the following configuration is adopted: the internal thread is configured as a left-hand thread or a right-hand thread.

[0018] To further improve the present invention, the following structure is adopted: the tube body includes a tube wall and a threaded tube that are coaxially assembled; the tube wall circumferentially surrounds the tube cavity, the outer peripheral wall of the threaded tube is fixedly connected to the inner peripheral wall of the tube wall, and the inner peripheral wall of the threaded tube is provided with the internal thread.

[0019] When the above-mentioned structure is adopted, the internal thread is formed on the threaded tube, and by setting the threaded tube on the tube wall, the slender tube body can be manufactured more stably.

[0020] To further improve the present invention, the following structure is adopted: at the distal end of the tube, a radially recessed mounting groove is provided on the inner circumferential surface of the tube wall, and the threaded tube is nested in the mounting groove for the entire circumference.

[0021] To further improve the implementation of this invention, the following structure is specifically adopted: the wall thickness of the threaded tube is less than the groove depth of the mounting groove.

[0022] To further improve the present invention, the following structure is provided: the outer peripheral wall of the threaded tube is provided with grooves for reducing the rigidity of the threaded tube.

[0023] When the above-mentioned structure is adopted, the grooves on the outer peripheral wall of the threaded pipe will make the threaded pipe more flexible and able to bend synchronously with the pipe wall.

[0024] The present invention has the following advantages and beneficial effects: The stent delivery conduit of this invention has a threaded rotating sleeve at its distal end, located within its lumen, forming a two-layer rotatable structure. Under the action of a tangential external force, the rotating sleeve can rotate circumferentially and move axially within the conduit. The inner circumferential wall of the rotating sleeve radially contacts and compresses the outer circumferential surface of the stent, utilizing the friction between the rotating sleeve and the stent to reliably constrain the inserted stent, ensuring smooth delivery in tortuous or narrow body cavities, avoiding the risk of stent dislodgement, and guaranteeing delivery safety.

[0025] After the distal end of the stent is pushed out by the pushing mechanism and anchored in the body cavity, a torsional difference occurs between the proximal and distal ends of the stent due to the torsion of the body cavity. The proximal end of the stent, in contact with the rotating sleeve, transmits torque to the rotating sleeve, causing the rotating sleeve to overcome its rotational resistance and rotate circumferentially relative to the tube body. This alleviates or even eliminates the torsional difference between the proximal and distal ends, effectively preventing the stent from kinking during delivery and release. Simultaneously, as the rotating sleeve rotates circumferentially relative to the tube body, it moves distally to release the stent while simultaneously eliminating the torsional difference between the proximal and distal ends. This allows the stent delivery catheter to utilize the torque generated by the stent's torsion, enabling the rotating sleeve to convert the obtained torque into the power for actively feeding and releasing the stent via a threaded engagement structure. This achieves the function of simultaneous active torque relief and assisted release, simplifying the stent delivery process and reducing operational complexity to a certain extent. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 This is a three-dimensional structural schematic diagram of the stent delivery catheter in some embodiments of this application, where the blue-filled portion represents the axial segment where the imaging section is located; Figure 2 This is a schematic diagram of the distal external structure of the stent delivery catheter in some embodiments of this application, where the blue-filled portion represents the axial segment where the imaging section is located; Figure 3 This is a schematic diagram of the distal internal structure of the stent delivery catheter in some embodiments of this application; Figure 4 This is a schematic diagram of the connection between the threaded pipe and the rotating sleeve in some embodiments of this application; Figure 5 This is a schematic diagram of the use of the stent delivery conduit in some embodiments of this application, in which the distal end of the stent has been extended and deployed; Figure 6This is a schematic diagram of the internal structure of the stent delivery catheter in some embodiments of this application, with the blue-filled portion indicating the axial section where the imaging section is located.

[0028] The diagram is marked as follows: 10. Tube body; 11. Tube cavity; 12. Internal thread; 13. Tube wall; 131. Mounting groove; 14. Threaded tube; 141. Groove; 15. Developing section; 20. Rotating sleeve; 21. Conveying channel; 22. External thread; 200. Bracket. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be described in detail below. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. Based on the embodiments of this application, all other implementation methods obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0030] In the description of this application, it should be noted that, unless otherwise stated, "multiple" means two or more; the terms "upper," "lower," "left," "right," "inner," "outer," "front end," "rear end," "head," "tail," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0031] The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such terms can be used interchangeably where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and the number of objects is not limited; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0032] In the description of this application, it should also be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this application depending on the specific circumstances.

[0033] In the various embodiments of this application, "near end" and "far end" refer to the distance of each component from the user in the usage environment. The end closer to the user is designated as the "near end", and the end farther from the user is designated as the "far end".

[0034] The inventors discovered in production practice that existing catheters used for stent delivery and control all feature a single-lumen, integrated design. The distal and proximal ends of the catheter are strictly coaxial, and the catheters are mostly made of rigid or semi-rigid materials. Because the catheter is a single unit, it lacks axial rotation adjustment capabilities, only allowing axial pushing and retraction. This easily leads to stent kinking. The core mechanism is as follows: during stent delivery within the catheter lumen, sufficient friction between the stent and the catheter wall is required to prevent stent dislodgement. However, when the distal end of the stent rotates due to resistance from vascular tortuosity or bifurcation, the catheter tip cannot follow the rotation, and the proximal end, restricted by the friction of the catheter wall, cannot rotate synchronously. This results in an imbalance of forces at both ends of the stent, ultimately causing twisting and kinking of the stent mid-section, obstructing the patency of the stent lumen, and affecting the normal release and adhesion of the stent to the vessel wall. In addition, different types of stents have different kinking characteristics. Braided stents are prone to "rolling" during testing, while cut-type and self-expanding stents are more likely to rotate distally and fix proximally in tortuous vascular segments due to their structural characteristics, thus causing kinking.

[0035] This application discloses a stent delivery conduit, the distal end of which is provided with a circumferentially rotatable rotating sleeve 20, which can synchronously move axially during circumferential rotation. When the stent 200 is twisted, the rotating sleeve 20 can be driven to rotate by the torque transmitted by the stent 200, thereby untwisting the stent 200 and simultaneously releasing the stent 200 to the distal end.

[0036] The following is in conjunction with the appendix Figures 1-6 The present application provides a detailed description of a stent delivery catheter through specific embodiments and application scenarios.

[0037] Embodiments of this application disclose a stent delivery catheter, such as Figure 1As shown, the stent delivery catheter is an axially elongated tube extending from the proximal end to the distal end, specifically including a tube body 10 for insertion into a human body cavity and a rotating sleeve 20 rotatably disposed inside the tube body 10.

[0038] The tube body 10 extends axially from its proximal end to its distal end, providing external protection. An axially penetrating lumen 11 is formed on the inner side of the tube body 10. The proximal port of the lumen 11 is formed on the proximal end face of the tube body 10, for receiving the insertion of relevant pushing mechanisms and necessary operating instruments. The distal port of the lumen 11 is formed on the distal end face of the tube body 10, for the release of the support 200. The distal end of the lumen 11 is used to house the rotating sleeve 20.

[0039] like Figure 3 and Figure 6 As shown, the rotating sleeve 20 extends axially from the proximal end to the distal end. An axially penetrating conveying channel 21 is formed on the inner side of the rotating sleeve 20. The proximal end of the conveying channel 21 is formed on the proximal end face of the rotating sleeve 20, and the distal end is formed on the distal end face of the rotating sleeve 20. The conveying channel 21 has an axially closed inner peripheral wall. The conveying channel 21 is used to radially contact and press the outer peripheral surface of the inserted support 200 through its inner peripheral wall. By utilizing the friction between the inner peripheral wall of the conveying channel 21 and the support 200, a reliable constraint is formed on the inserted support 200, so that the support 200 is stably supported. This ensures smooth delivery in tortuous or narrow human body cavities, avoids the risk of support 200 dislodging, and ensures delivery safety.

[0040] like Figure 2 and Figure 3 As shown, the tube body 10 has an internal thread 12 that extends spirally along the axial direction of the tube cavity 11 on the wall of the tube cavity 11. The entire internal thread 12 is located at the far end of the tube body 10.

[0041] like Figure 3 and Figure 6 As shown, the rotating sleeve 20 is coaxially disposed in the cavity 11 inside the tube body 10. The rotating sleeve 20 has an external thread 22 extending helically along its outer circumference. Within the cavity 11, the rotating sleeve 20 engages with the internal thread 12 on the wall of the cavity 11 of the tube body 10 via its external thread 22. This allows the rotating sleeve 20 to rotate relative to the tube body 10 under the circumferential driving force of the support 200 when subjected to external forces, such as the tangential frictional force applied to the inner circumferential wall of the support 200. Because the rotating sleeve 20 is movably connected to the tube body 10 via threaded engagement, it can move axially relative to the tube body 10 during its circumferential rotation.

[0042] In this embodiment, the stent delivery conduit has a rotating sleeve 20 connected to the distal end of the tube body 10 via a threaded engagement, forming a two-layer rotatable structure with the tube body 10 on the outside and the rotating sleeve 20 on the inside. Under the action of a tangential external force, the rotating sleeve 20 can rotate circumferentially and move axially within the tube body 10.

[0043] When the rotating sleeve 20 stably constrains the stent 200 through its inner circumferential wall, after the stent 200 is pushed by the pushing mechanism so that its distal end is pushed out of the distal port of the lumen 11 and anchored to the wall of the human body cavity, if the stent 200 twists due to the tortuosity of the human body cavity, the stent 200 will transmit the torque generated thereon to the rotating sleeve 20 through its proximal end in contact with the rotating sleeve 20, so that the rotating sleeve 20 can rotate circumferentially relative to the tube body 10 while overcoming its rotational resistance. When the rotating sleeve 20 rotates circumferentially, it can conform to the torsional tendency of the stent 200, alleviate or even eliminate the torsional difference between the proximal and distal ends of the stent 200, and thus prevent the stent 200 from twisting during the delivery and release process.

[0044] It should be noted that, in this embodiment, the stent delivery catheter aims to achieve both de-twisting of the stent 200 and, when the stent 200 rotates due to its twisting, allow the rotating sleeve 20 to advance towards the distal end of the tube body 10, i.e., the distal end of the lumen 11. Therefore, the direction of the internal thread 12 on the wall of the lumen 11 of the tube body 10 should be pre-selected based on the tortuous direction of the human body cavity. Thus, the internal thread 12 on the wall of the lumen 11 of the tube body 10 can be either a left-hand thread or a right-hand thread. However, the internal thread 12 of a single stent delivery catheter can only be either a left-hand thread or a right-hand thread.

[0045] Since the rotating sleeve 20 is connected to the tube body 10 via a threaded engagement, it moves axially when rotating circumferentially relative to the tube body 10. By assessing the tortuosity and twisting direction of the body cavity (such as a blood vessel) preoperatively using DSA angiography and selecting a suitable stent delivery catheter with appropriate internal thread 12 rotation direction, the rotating sleeve 20 can move distally while rotating circumferentially; it can also release the stent by moving distally while eliminating the torsional difference between the proximal and distal ends of the stent 200. Therefore, this stent delivery catheter can utilize the torque generated by the torsion of the stent 200, allowing the rotating sleeve 20 to convert the obtained torque into the power for actively feeding and releasing the stent 200 through the threaded engagement structure. This achieves the function of simultaneous active torque relief and assisted release, simplifying the stent delivery process and reducing operational complexity to a certain extent.

[0046] In one application scenario, the direction of vascular tortuosity and twist is assessed preoperatively via DSA angiography. If the vessel is right-handed, a stent delivery catheter with a left-handed internal thread of 12 is selected; if the vessel is left-handed, a stent delivery catheter with a right-handed internal thread of 12 is selected. The stent delivery catheter is advanced along the guidewire into the tortuous lesion vessel. The distal end of the stent 200 is pushed to the target site via a delivery mechanism inserted through the lumen 11. The distal end of the stent 200... Figure 5 and Figure 6 As shown, the stent is first dislodged and inserted into the lumen 11, unfolded, and anchored to the inner wall of the blood vessel. As the stent delivery catheter continues to withdraw to release the remaining stent 200, if the distal end of the stent 200 experiences torsion due to vascular tortuosity, the torque acts directly on the rotating sleeve 20 because the proximal end of the stent 200 is constrained by the inner circumferential wall of the rotating sleeve 20. After overcoming the friction with the internal thread 12, the rotating sleeve 20 follows the proximal end of the stent 200 in a circumferential rotation, releasing the torsional stress in real time. This alleviates or even eliminates the torsional difference between the proximal and distal ends of the stent 200, preventing mid-section kinking or curling of the stent 200 throughout the process. After the stent 200 is fully released, the entire stent delivery catheter is withdrawn from the blood vessel. During the detwisting process of the stent 200, the rotating sleeve 20 is fed axially towards the distal end, gradually pushing to release the stent 200. The greater the torque applied by the stent 200 to the rotating sleeve 20, the faster the feeding and release speed of the rotating sleeve 20. If the distal end of the stent 200 does not twist but opens normally against the wall, then during the retraction of the stent delivery catheter, the rotating sleeve 20 is not driven by the stent 200 and does not rotate circumferentially, and the stent 200 is released normally.

[0047] According to some optional embodiments, in order to ensure that the pushing mechanism can smoothly push the support 200 and that the rotating sleeve 20 can smoothly help the support 200 to untwist, the rotating sleeve 20 of the support delivery conduit is strictly coaxial with the tube body 10, so that the delivery channel 21 provided at the center of the rotating sleeve 20 and the cavity 11 provided at the center of the tube body 10 are coaxially arranged.

[0048] According to some optional embodiments, such as Figure 3 and Figure 6 As shown, the diameter of the delivery channel 21 located inside the rotating sleeve 20 of the stent delivery conduit is smaller than the diameter of the lumen 11, so that the inner circumference of the delivery channel 21 is entirely located inside the lumen 11 wall located inside the tube body 10. The stent 200, constrained by the inner circumference of the rotating sleeve 20, can detach from the lumen 11 wall or reduce the radial compressive force with the lumen 11 wall, allowing the stent 200 to transfer as much torque as possible to the rotating sleeve 20, and enabling the stent 200 to eliminate its proximal-distal torsional difference as easily as possible.

[0049] According to some optional embodiments, in order to prevent the rotating sleeve 20 from being driven to rotate by the stent 200 when the stent 200 has not twisted, the rotating sleeve 20 of the stent delivery conduit has a self-locking property when its external thread 22 engages with the internal thread 12 of the tube body 10. This effectively prevents the rotating sleeve 20 from rotating due to axial movement of the stent 200 relative to the rotating sleeve 20, thereby avoiding premature release of the stent 200 or undesirable twisting of the stent 200, making the release process of the stent 200 more controllable.

[0050] According to some optional embodiments, such as Figure 6 As shown, the axial length of the rotating sleeve 20 of the stent delivery catheter is set to be less than the axial length of the stent 200 to be inserted into the human body cavity.

[0051] According to some optional embodiments, in order to ensure the manufacturing difficulty of the tube body 10, the axial length of the internal thread 12 provided in the tube body 10 is less than or equal to the axial length of the bracket 200.

[0052] According to some optional embodiments, the axial distance between the distal end of the internal thread 12 provided on the tube body 10 and the distal end face of the tube body 10 is less than or equal to 1.2 mm, such as 1.0 mm, so that the tube body 10 has a complete and smooth inner peripheral wall at the distal end of the lumen 11, which can reduce the possibility of distal thrombosis to a certain extent and better protect the walls of narrow and tortuous cavities such as blood vessels.

[0053] According to some optional embodiments, the stent delivery catheter has a hydrophilic or hydrophobic coating on the inner peripheral wall of the rotating sleeve 20. The hydrophilic or hydrophobic coating can be formed on the inner peripheral wall of the rotating sleeve 20 by means of spraying, dipping, plasma surface treatment, ionization displacement, etc., which can effectively prevent thrombosis.

[0054] According to some optional embodiments, such as Figure 1 , Figure 2 and Figure 6 As shown, the stent delivery catheter has a radiopaque section 15 at the distal end of its tube body 10. The radiopaque section 15 is circumferentially closed around the tube body 10 and has a certain axial dimension, so that the radiopaque image can be observed in real time during the operation via DSA.

[0055] The axial length of the developing section 15 is generally 0.8mm-1.2mm, preferably 1.0mm. In order for the developing section 15 to better reflect the position of the distal end of the tube body 10, the axial distance between the developing section 15 and the distal end face of the tube body 10 is set to 0.6mm-1.2mm, with 1.0mm being optimal.

[0056] The radiopaque portion 15 can be formed on the inner or outer peripheral wall of the tube body 10 by coating with a radiopaque coating. Alternatively, the radiopaque portion 15 can be formed in the tube wall of the tube body 10 by mixing a high-density radiopaque substance into the material during the manufacturing process. With the radiopaque portion 15 provided on the tube body 10, the position of the distal end of the stent delivery catheter can be observed in real time during the operation, which facilitates the surgeon to accurately control the release process of the stent 200.

[0057] According to some optional embodiments, in order to facilitate control over the production quality of the elongated tube 10, such as Figure 3 , Figure 4 and Figure 6 As shown, the tube body 10 of the stent delivery conduit is an assembly, comprising a tube wall 13 and a threaded tube 14, which are coaxially arranged and assembled. The tube wall 13 circumferentially encloses the cavity 11, and the threaded tube 14 extends axially from the proximal end to the distal end. The outer circumferential wall of the threaded tube 14 is fixedly connected to the inner circumferential wall of the tube wall 13 by adhesive bonding and / or magnetic attraction, preventing the threaded tube 14 from axially shifting or circumferentially rotating relative to the tube wall 13. The inner circumferential wall of the threaded tube 14 is provided with an internal thread 12, and a rotating sleeve 20 is disposed inside the threaded tube 14 and threadedly engaged with the internal thread 12.

[0058] In this embodiment, the support delivery conduit allows the internal thread 12 to be formed on the threaded tube 14, and by setting the threaded tube 14 on the tube wall 13, the slender tube body 10 can be manufactured more stably.

[0059] Of course, according to some alternative embodiments, the internal thread 12 of the tube body 10 of the stent delivery conduit is formed integrally on the tube body 10.

[0060] According to some optional embodiments, such as Figure 6 As shown, at the distal end of the pipe body 10, the support delivery conduit has a radially recessed mounting groove 131 on the inner circumferential surface of the pipe wall 13. The mounting groove 131 has a certain axial length and is closed circumferentially. The threaded pipe 14 is nested entirely within the mounting groove 131.

[0061] In some embodiments, the cross-section of the mounting groove 131 is U-shaped, and the threaded tube 14 is nested in the mounting groove 131 and is axially restricted by the two groove walls in the axial direction of the mounting groove 131 to prevent the threaded tube 14 from moving axially.

[0062] In some embodiments, such as Figure 6 As shown, the wall thickness of the threaded tube 14 is less than the groove depth of the mounting groove 131, so that the external thread on the outer periphery of the rotating sleeve 20 is located in the mounting groove 131 and engages with the internal thread 12. This allows the wall thickness of the rotating sleeve 20 to be thicker, preventing the rotating sleeve 20, which directly constrains the bracket 200, from undergoing undesirable bending relative to the tube wall 13, thus affecting its smooth rotation relative to the tube body 10.

[0063] To reduce the stiffness of the threaded tube 14, allowing it to bend more synchronously with the tube body 10, and to reduce the different degrees of bending between the threaded tube 14 and the tube wall 13, some alternative embodiments, such as... Figure 4 As shown, the stent delivery conduit has a groove 141 on the outer peripheral wall of the threaded tube 14 to reduce the rigidity of the threaded tube 14. This groove 141 does not penetrate the wall of the threaded tube 14, so that the internal thread 12 on the inner peripheral wall of the threaded tube 14 is continuous and complete. The groove on the outer peripheral wall of the threaded tube 14 makes the threaded tube 14 more flexible and can bend synchronously with the tube wall 13, thus allowing the tube body 10 to adapt well to the curvature of the human body cavity and have good bending performance.

[0064] Groove 141 can be like Figure 4 As shown, it can be set to a shape that is wide in the middle and narrow at both ends in the extension direction, or it can be a shape that is equal in width in the extension direction.

[0065] Existing catheters only establish access through their lumens to deliver stents to the lesion site, but they cannot address the stent kinking that occurs after passing through tortuous blood vessels, or the resulting loss of the lumen. The stent delivery catheter of this application employs a rotating sleeve 20 at its distal end, which can helically rotate relative to the tube body 10. Whether the torsion occurs during the delivery system's journey through the tortuous blood vessel or as the stent 200 gradually opens from the distal tortuous vessel, the rotating sleeve 200 can untwist the proximal end of the stent 200, ultimately preventing further torsion and maintaining the patency of the internal lumen of the stent 200. This improves surgical efficiency and the success rate of the first attempt. It reduces the need for repeated retrieval and resetting actions to deal with stent kinking, effectively reducing the risk of stent dislodgement and deformation, thereby improving the success rate of stent implantation and treatment safety. It effectively avoids post-stent remedial procedures, such as preventing balloon dilation and surgical stent removal after severe stent kinking, reducing post-operative complications caused by traditional remedial surgeries, and minimizing the risks of intimal tearing, bleeding, and stent retention.

[0066] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0067] Furthermore, it should be noted that the scope of the methods and apparatus in the embodiments of this application is not limited to performing functions in the order shown or discussed, but may also include performing functions substantially simultaneously or in the reverse order, depending on the functions involved. For example, the described methods may be performed in a different order than described, and various steps may be added, omitted, or combined. In addition, features described with reference to certain examples may be combined in other examples.

[0068] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application.

Claims

1. A stent delivery catheter, characterized in that: include: The tube body (10) extends axially from the proximal end to the distal end, and the inner side of the tube body (10) is provided with an axially penetrating cavity (11); at the distal end of the tube body (10), the cavity wall of the cavity (11) is provided with an axially extending internal thread (12). A rotating sleeve (20) is coaxially arranged with the tube body (10). An axially penetrating conveying channel (21) is provided on the inner side of the rotating sleeve (20). The inner circumferential wall of the conveying channel (21) is used to radially contact and squeeze the outer circumferential surface of the bracket (200) placed therein. An external thread (22) is provided on the outer circumference of the rotating sleeve (20). The rotating sleeve (20) is disposed in the tube cavity (11) and is threadedly engaged with the internal thread (12) through the external thread (22), so that the rotating sleeve (20) can rotate relative to the tube body (10) under the circumferential driving action of the bracket (200).

2. The stent delivery catheter according to claim 1, characterized in that: The delivery channel (21) is coaxially arranged with the cavity (11).

3. The stent delivery catheter according to claim 2, characterized in that: The diameter of the delivery channel (21) is smaller than the diameter of the cavity (11).

4. The stent delivery catheter according to claim 1, characterized in that: The rotating sleeve (20) is self-locking by the engagement of the external thread (22) with the internal thread (12).

5. A stent delivery catheter according to claim 1, characterized in that: The axial length of the rotating sleeve (20) is less than the axial length of the bracket (200); And / or, the axial length of the internal thread (12) is less than or equal to the axial length of the bracket (200); And / or, the axial distance between the distal end of the internal thread (12) and the distal end face of the tube body (10) is less than or equal to 1.2 mm.

6. The stent delivery catheter according to claim 1, characterized in that: The inner peripheral wall of the rotating sleeve (20) is provided with a hydrophilic or hydrophobic coating; And / or, the distal end of the tube body (10) is provided with a developing section (15) having developing properties, the developing section (15) is circumferentially closed around the tube body (10), the axial distance of the developing section (15) from the distal end face of the tube body (10) is 0.6mm-1.2mm, and the axial length of the developing section (15) is 0.8mm-1.2mm.

7. The stent delivery catheter according to claim 1, characterized in that: The internal thread (12) is configured as a left-hand thread or a right-hand thread.

8. A stent delivery catheter according to any one of claims 1-7, characterized in that: The tube body (10) includes a tube wall (13) and a threaded tube (14) coaxially assembled; the tube wall (13) is arranged to circumferentially surround the tube cavity (11), the outer peripheral wall of the threaded tube (14) is fixedly connected to the inner peripheral wall of the tube wall (13), and the inner peripheral wall of the threaded tube (14) is provided with the internal thread (12).

9. A stent delivery catheter according to claim 8, characterized in that: At the far end of the tube body (10), the inner circumferential surface of the tube wall (13) is provided with a radially recessed mounting groove (131), and the threaded tube (14) is nested in the mounting groove (131) for the entire circumference.

10. A stent delivery catheter according to claim 9, characterized in that: The wall thickness of the threaded pipe (14) is less than the groove depth of the mounting groove (131); And / or, the outer peripheral wall of the threaded tube (14) is provided with grooves (141) for reducing the rigidity of the threaded tube (14).

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