A delivery conduit mechanism and a support delivery device

Abstract

This invention belongs to the field of medical device technology, and specifically relates to a delivery catheter mechanism and a stent delivery device. The delivery catheter mechanism includes a sheath core and a tapered guide tube. The tapered guide tube is fitted onto the distal end of the sheath core and extends beyond it. The outer diameter of the tapered guide tube gradually decreases in the direction away from the distal end of the sheath core. A flow-guiding groove is formed on the outer wall of the tapered guide tube, located proximal to the distal end of the tapered guide tube relative to the distal end of the sheath core and spaced apart from it. This invention, through the above structure, avoids the sheath core being exposed, ensuring the safety and structural strength of the delivery catheter mechanism during intravascular delivery.

Description

Technical Field

[0001] This invention belongs to the field of medical device technology, and in particular relates to a catheter delivery mechanism and a stent delivery device. Background Technology

[0002] Inserting a stent into the lesion site in a patient's body via a body cavity is a common interventional procedure. For example, stents are implanted in coronary arteries, peripheral arteries, iliac veins, etc., to treat vascular stenosis. Or, a endovascular stent graft is implanted in the aorta to treat arterial dissection. Depending on the actual needs, the stent can also be loaded with drugs to achieve better treatment results.

[0003] The stent needs to be implanted into the patient's body using a delivery catheter. The delivery catheter usually includes a sheath core and a guide tube. The guide tube is assembled at the distal end of the sheath core and has great flexibility. During the process of pushing the guide tube into the human blood vessel, the guide tube can pass through tortuous blood vessel parts, ensuring the smooth deployment of the guide tube to the target blood vessel site.

[0004] However, some products have drainage grooves on the guide tube, such as... Figure 1 As shown, the drainage groove 41 covers the entire distal area of ​​the sheath core tube 6. The structure of the guide tube 4 at the location of the drainage groove 41 is relatively weak. When passing through the tortuous blood vessel, the distal end of the sheath core tube 6 is prone to penetrate the drainage groove 41 and puncture the guide tube 4, which affects the safety of delivery and also weakens the overall structure of the delivery catheter, which is not conducive to subsequent delivery.

[0005] Moreover, existing products typically use adhesive bonding to assemble the guide tube onto the sheath core tube. Chinese patent publication number CN215083921U provides an implementation method that increases the connection strength between the two by assembling an auxiliary tube between the guide tube and the sheath core tube to enhance the connection strength between them.

[0006] Continue to refer to Figure 1 However, the addition of the auxiliary tube 5 occupies part of the position that should have been the guide tube 4, and the drainage groove 41 also covers the entire auxiliary tube 5, making the structure of the guide tube 4 at the drainage groove 41 position weaker. It is more likely to be punctured by the offset of the sheath core tube 6 or the auxiliary tube 5. For example, during the production and processing of the catheter, the auxiliary tube 5 is prone to being eccentric relative to the sheath core tube 6 before the adhesive solidifies. When assembling the guide tube 4, it is easy to puncture the guide tube 4 at the structurally weak drainage groove 41 position, causing the auxiliary tube 5 to be exposed at that point. Moreover, the auxiliary tube 5 is a metal tube, and the exposed part is in direct contact with blood, which can easily lead to infection. Furthermore, the rupture of the guide tube will also affect the structural strength of the delivery catheter.

[0007] The inventors discovered that increasing the outer diameter of the guide tube to increase the wall thickness to solve the problem of preventing the auxiliary tube from being exposed would lead to the consequence of increasing the overall size of the guide tube, which would be detrimental to guiding and conveying. Therefore, there is an urgent need to provide a new design to solve the above problems. Summary of the Invention

[0008] This invention addresses the technical problem in the prior art where the sheath core tube and auxiliary tube easily penetrate the guide tube and are exposed to the outside, by providing a delivery catheter mechanism and a support delivery device.

[0009] In view of the above technical problems, embodiments of the present invention provide a delivery catheter mechanism, including a sheath core tube and a tapered guide tube, wherein the tapered guide tube is sleeved on the distal end of the sheath core tube and extends beyond the distal end of the sheath core tube, and the outer diameter of the tapered guide tube gradually decreases in the direction away from the distal end of the sheath core tube;

[0010] The outer wall of the tapered guide tube is provided with a flow guiding groove, which is located on the proximal side of the tapered guide tube relative to the distal end of the sheath core tube and is spaced apart from the distal end of the sheath core tube.

[0011] Optionally, it also includes an auxiliary tube, which is sleeved on the distal end of the sheath core tube and sleeved by the tapered guide tube. The auxiliary tube is located on the distal side of the flow guiding groove. The auxiliary tube includes a proximal section and a distal section arranged coaxially. At least a portion of the flow guiding groove is disposed on the outer wall of the tapered guide tube sleeved on the proximal section.

[0012] Optionally, the tapered guide tube includes a first tapered tube section and a straight tube section arranged coaxially. From one end closer to the straight tube section toward the end farther from the straight tube section, the outer diameter of the first tapered tube section gradually decreases. The straight tube section is sleeved on the sheath core tube, and the first tapered tube section is sleeved on the auxiliary tube.

[0013] The flow guiding groove includes a first groove, which is disposed on the outer wall of the first tapered tube section.

[0014] Optionally, the flow guiding groove further includes a second groove communicating with the first groove, the second groove being disposed on the outer wall of the straight pipe section sleeved on the sheath core tube.

[0015] Optionally, the bottom wall of the first groove is an inclined wall, and the distance between the inclined wall and the axis of the tapered guide tube gradually increases from the end closer to the second groove toward the end farther away from the second groove.

[0016] Optionally, the outer diameter of the proximal segment gradually decreases from the end closest to the distal segment toward the end furthest from the distal segment.

[0017] Optionally, the outer wall of the distal segment is provided with a plurality of helical teeth spaced apart, and the distance between the helical teeth and the axis of the auxiliary tube gradually decreases from the end closer to the proximal segment toward the end farther from the proximal segment.

[0018] Optionally, the tapered guide tube has an inner hole, the inner hole including a tapered section and a straight section that are coaxially connected, the proximal section is installed in the tapered section, and the outer wall of the proximal section abuts against the inner wall of the tapered section; the distal section is installed in the straight section, and the outer wall of the distal section abuts against the inner wall of the straight section.

[0019] Optionally, the length of the first groove is less than two-thirds of the length of the proximal segment.

[0020] Optionally, the width of the flow guide groove gradually increases from one end near the axis of the tapered guide tube toward the end away from the axis of the tapered guide tube.

[0021] Another embodiment of the present invention provides a stent delivery device, including an outer sheath and the aforementioned delivery conduit mechanism; the outer sheath is sleeved on the sheath core tube and the tapered guide tube.

[0022] In this invention, the flow-guiding groove on the tapered guide tube is positioned proximal to the distal end of the tapered guide tube relative to the sheath core tube, and spaced apart from the distal end of the sheath core tube. By shortening the flow-guiding groove on the tapered guide tube, positioning it proximal to the tapered guide tube and offset from the distal end of the sheath core tube, the distal end of the tapered guide tube, which has a smaller outer diameter, is prevented from being punctured by the sheath core tube through the flow-guiding groove. This prevents the sheath core tube from being exposed, ensuring the safety of the delivery catheter mechanism during intravascular delivery. Furthermore, the sufficient wall thickness on the distal end of the tapered guide tube ensures the overall strength of the delivery catheter mechanism. Attached Figure Description

[0023] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0024] Figure 1 The accompanying drawings are related to the catheter technology mentioned in the background section of this invention;

[0025] Figure 2 This is a schematic diagram of the delivery conduit mechanism provided in an embodiment of the present invention;

[0026] Figure 3 This is a front view of a delivery conduit mechanism provided in an embodiment of the present invention;

[0027] Figure 4 This is an axial sectional view of a delivery conduit mechanism provided in an embodiment of the present invention.

[0028] The reference numerals in the accompanying drawings are as follows:

[0029] 1. Sheath core tube; 2. Tapered guide tube; 21. Flow guide groove; 211. First groove; 212. Second groove; 22. First tapered tube section; 23. Straight tube section; 24. Second tapered tube section; 25. Tapered hole section; 26. Straight hole section; 3. Auxiliary tube; 31. Proximal section; 32. Distal section; 321. Helical teeth. Detailed Implementation

[0030] To make the technical problems solved, the technical solutions, and the beneficial effects of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only for explaining the invention and are not intended to limit the invention.

[0031] It should be understood that the terms "upper", "lower", "left", "right", "front", "rear", "middle", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the present invention 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. Therefore, they should not be construed as limitations of the present invention.

[0032] like Figures 1 to 3 As shown, an embodiment of the present invention provides a catheter delivery mechanism, including a sheath core tube 1 and a tapered guide tube 2. The tapered guide tube 2 is sleeved on the distal end of the sheath core tube 1 and extends beyond the distal end of the sheath core tube 1. The outer diameter of the tapered guide tube 2 gradually decreases in the direction away from the distal end of the sheath core tube 1, thus guiding the advancement of the sheath core tube 1 within the blood vessel. The inner lumen of the sheath core tube 1 communicates with the distal opening of the tapered guide tube 2, so that the guidewire can pass through the inner lumen of the sheath core tube 1 and pass through the distal end of the tapered guide tube 2.

[0033] The tapered guide tube 2 has a drainage groove 21 on its outer wall for draining saline solution used to clean the sheath core tube 1. The drainage groove 21 is located proximal to the distal end of the tapered guide tube 2 relative to the distal end of the sheath core tube 1, and is spaced apart from the distal end of the sheath core tube 1. By shortening the drainage groove 21 on the tapered guide tube 2, positioning it proximal to the tapered guide tube 2 and offset from the distal end of the sheath core tube 1, the distal end of the tapered guide tube 2, which has a smaller outer diameter, is prevented from being punctured by the sheath core tube 1, thus preventing the sheath core tube 1 from being exposed and ensuring the safety of the delivery catheter mechanism during intravascular delivery. Furthermore, the sufficient wall thickness of the distal end of the tapered guide tube 2 ensures the overall strength of the delivery catheter mechanism.

[0034] In one embodiment, the delivery catheter mechanism further includes an auxiliary tube 3, which is sleeved on the distal end of the sheath core tube 1 and connected to a tapered guide tube 2. The sheath core tube 1 and the tapered guide tube 2 are made of polymer material, while the auxiliary tube 3 can be made of metal. The two opposite sides of the auxiliary tube 3 are connected to the sheath core tube 1 and the tapered guide tube 2, respectively, so that the tapered guide tube 2 and the sheath core tube 1 do not slide axially or radially and form an integrated structure. Moreover, the auxiliary tube 3 serves as a transition connection, significantly enhancing the connection strength and reliability between the two plastic components. This results in a stable fixed connection between the sheath core tube 1 and the tapered guide tube 2, which helps to transmit force and also reduces the risk of the tapered guide tube 2 falling off.

[0035] In one embodiment, while ensuring the wall thickness of the auxiliary tube 3, the inner diameter of the auxiliary tube 3 can be increased, so that there is more space for glue to fill between the inner wall of the auxiliary tube 3 and the outer wall of the sheath core tube 1, thereby increasing the bonding strength of the auxiliary tube 3.

[0036] Specifically, in this embodiment, the auxiliary tube 3 is located on the far side of the flow-guiding groove 21. The auxiliary tube 3 includes a proximal section 31 and a distal section 32 arranged coaxially. At least a portion of the flow-guiding groove 21 is disposed on the outer wall of the tapered guide tube 2 sleeved on the proximal section 31. It can be understood that, if projected onto the sheath core tube 1, at least a portion of the flow-guiding groove 21 overlaps with the projection of the proximal section 21. That is, the flow-guiding groove 21 does not completely cover the entire auxiliary tube 3, but is staggered from the auxiliary tube 3 to a certain extent, ensuring the structural strength of the tapered guide tube 2 at the distal end and preventing it from being easily punctured by the distal end of the auxiliary tube 3.

[0037] In one embodiment, such as Figures 1 to 3 As shown, the tapered guide tube 2 includes a first tapered tube section 22 and a straight tube section 23 arranged coaxially. The outer diameter of the first tapered tube section 22 gradually decreases from the end closest to the straight tube section 23 towards the end furthest from it. Understandably, the connection surface between the first tapered tube section 22 and the straight tube section 23 is a stepped surface. The first tapered tube section 22 has a larger outer diameter than the straight tube section 23 at the step, and the first tapered tube section 22 and the straight tube section 23 are connected by this step. The step facilitates the subsequent installation of the outer sheath tube, and the step abuts against the outer sheath tube, thus limiting its movement.

[0038] The straight pipe section 23 is sleeved on the sheath core tube 1, and the first tapered pipe section 22 is sleeved on the auxiliary pipe 3; furthermore, the first tapered pipe section 22 is sleeved on the distal section 32 and the proximal section 31.

[0039] The flow guide groove 21 includes a first groove 211, which is disposed on the outer wall of the first tapered tube section 22 sleeved on the proximal section 31.

[0040] The flow guide groove 21 also includes a second groove 212 that connects to the first groove 211. The second groove 212 is disposed on the outer wall of the straight pipe section 23 and is offset from the near-end region of the auxiliary pipe 3. In this embodiment, the outer periphery of the sheath core tube 1 is directly the straight pipe section 23 without the auxiliary pipe 3. Therefore, the straight pipe section 23 has sufficient wall thickness and is less likely to be punctured compared to the position where the auxiliary pipe 3 is provided.

[0041] In one embodiment, such as Figure 1 and Figure 2 As shown, the second groove 212 is straight along the axial direction on the outer wall of the straight pipe section 23, and the bottom wall of the first groove 211 is an inclined wall. From the end near the second groove 212 to the end away from the second groove 212, the distance between the inclined wall and the axis of the tapered guide pipe 2 gradually increases, so as to form a scheme in which the guide groove 21 extends outward from the position of the auxiliary pipe 3, making the tapered guide pipe 2 thicker and stronger at the position of the auxiliary pipe 3.

[0042] In one embodiment, the first groove 211 is deeper at the end near the second groove 212 and shallower at the end away from the second groove 212. The second groove 212 is straight along the axial direction on the outer wall of the straight tube section 23, and the first groove 211 is inclined and expanded outward, so that physiological saline can flush the sheath core tube and flow smoothly out toward the distal first groove 211.

[0043] Specifically, the first groove 211 has a first end communicating with the second groove 212 and a second end relatively far away from the second groove 212. The flow guide groove 21 gradually slopes outward from the first end of the first groove 211 to the second end, forming an outwardly expanding groove. The tapered guide tube 2 has guide grooves 21 on opposite sides. It can be understood that the distance between the second ends of the first grooves 211 on opposite sides is greater than the distance between the first ends.

[0044] In one embodiment, such as Figures 1 to 3 As shown, the tapered guide tube 2 is fitted onto the proximal section 31 and the distal section 32; the outer diameter of the proximal section 31 gradually decreases from the end closer to the distal section 32 toward the end farther from the distal section 32. It can be understood that the proximal section 31 is a tapered tubular structure, and the distal section 32 is a straight tubular structure.

[0045] Because of the design of the flow guide groove 21, the wall thickness of the tapered guide tube 2 at this position is very limited and the structural strength is relatively weak. Therefore, in order to prevent the tapered guide tube 2 from breaking, the auxiliary tube 3 located at the tapered guide tube 2 with a thinner wall is designed to be tapered, and the thickness of the auxiliary tube 3 is reduced to increase the wall thickness of the tapered guide tube 2 at this position.

[0046] In this invention, the design of the tapered guide tube 2 not only guides the sheath core tube 1 during its delivery within the blood vessel, but also, by reducing the outer diameter of the auxiliary tube 3, increases the wall thickness of the tapered guide tube 2 surrounding the auxiliary tube 3 without increasing its overall size. This makes it less likely for the flow-guiding groove 21 to penetrate the tapered guide tube 2, thus preventing the sheath core tube 1 and auxiliary tube 3 from being exposed and ensuring the safety of the delivery catheter mechanism during intravascular delivery. Furthermore, the sufficient wall thickness of the tapered guide tube 2 surrounding the auxiliary tube 3 ensures the strength of the tapered guide tube 2.

[0047] In other embodiments, a straight cylindrical auxiliary tube can also be used, and the conical guide tube 2 with only the outwardly expanding flow guide groove 21 can also achieve the effect of increasing the material thickness between the conical guide tube 2 and the auxiliary tube 3.

[0048] Furthermore, in one embodiment, a structure is included that simultaneously comprises an outwardly expanding flow guide groove and a tapered auxiliary tube. The flow guide groove 21 is configured as an outwardly expanding groove. While the auxiliary tube 3 is tapered, providing sufficient wall thickness for the tapered guide tube, the outwardly expanding groove further increases the wall thickness space of the tapered guide tube 2 at the groove. In this embodiment, since the tapered guide tube 2 surrounding the proximal segment 31 has sufficient wall thickness, the first groove 211 is positioned on the outer wall of the tapered guide tube 2 surrounding the proximal segment 31, further ensuring that the first groove 211 does not easily penetrate the tapered guide tube 2, making the auxiliary tube 3 less likely to be exposed, thereby further ensuring the safety of the delivery catheter mechanism in intravascular delivery.

[0049] The first groove 211 is positioned relative to the proximal segment 31 and extends outward. Understandably, the wall thickness of the proximal segment 31 of the auxiliary tube 3 gradually decreases from the end closer to the distal segment 32 towards the end farther from the distal segment 32. Compared to the prior art where straight-tube auxiliary tubes easily penetrate tapered guide tubes, the tapered auxiliary tube 3 of this application reserves sufficient injection volume for the tapered guide tube 2 in the tapered region. This means the bottom of the flow-guiding groove 21 is further away from the auxiliary tube 3, and there is a certain wall thickness of the tapered guide tube 2 between them. This effectively prevents the auxiliary tube 3 from piercing the tapered guide tube 2 at the flow-guiding groove 21, thereby avoiding the risk of the auxiliary tube 3 being exposed and coming into contact with blood.

[0050] Because the straight tube section 23 surrounding the proximal segment 31 has sufficient wall thickness, the second groove 212 is positioned on the outer wall of the first tapered tube section 22 surrounding the proximal segment 31, further ensuring that the first groove 211 is not easily penetrated by the tapered guide tube 2. Furthermore, the design of the straight tube section 23 ensures the stability of the tapered guide tube 2 fitted onto the sheath core tube 1. In addition, after the catheter assembly is assembled, an outer sheath tube is fitted over the sheath core tube 1. Before implantation, physiological saline needs to be infused to disinfect the inside of the catheter assembly. The design of the first groove 211 and the second groove 212 allows the physiological saline at the outer end of the delivery catheter mechanism to easily flow out through the second groove 212 and the first groove 211, thereby improving the ease of cleaning the delivery guide mechanism.

[0051] In one embodiment, such as Figure 1 and Figure 3 As shown, the outer wall of the distal segment 32 is provided with a plurality of spaced oblique teeth 321; from the end closer to the proximal segment 31 toward the end farther from the proximal segment 31, the distance between the oblique teeth 321 and the axis of the auxiliary tube 3 gradually decreases, that is, the inclination direction of the oblique teeth 321 is compliant from the distal end to the proximal end. Understandably, there is an oblique groove between two adjacent oblique teeth 321, in which more tapered guide tube 2 material can be injected, ensuring the stability of the tapered guide tube 2 fitted onto the auxiliary tube 3. Furthermore, the oblique teeth 321 are inclined toward the proximal end of the auxiliary tube 3, making it difficult for the tapered guide tube 2 to be pulled out of the auxiliary tube 3, further ensuring the stability of the tapered guide tube 2 fitted onto the auxiliary tube 3.

[0052] Furthermore, the segmented design of the tapered proximal section 31 and the straight distal section 32 of the auxiliary tube 3 helps to distinguish the assembly direction of the auxiliary tube 3 during the assembly of the catheter mechanism. The proximal section 31 is assembled on the inner side of the sheath core tube 1, so that the tip of the helical tooth 321 can face the proximal side of the tapered guide tube 2, effectively strengthening the connection strength between the tapered guide tube 2 and the auxiliary tube 3, and preventing the tapered guide tube 2 from coming off from the distal end.

[0053] In one embodiment, such as Figures 1 to 3 As shown, the length of the first groove 211 is less than two-thirds of the length of the proximal segment 31. In this embodiment, the length of the first groove 211 is small, only half the length of the proximal segment 31, which makes the proximal segment 31 where the first groove 211 is located have a thicker wall, further ensuring that the first groove 211 is not easy to penetrate the tapered guide tube 2.

[0054] The auxiliary tube 3 is positioned between the step of the tapered guide tube and the distal end of the sheath core tube 1. Specifically, the proximal section 31 of the auxiliary tube 3 has a starting end and a stopping end. The starting end is the proximal end of the auxiliary tube 3, and the stopping end is the end connected to the distal section 32. The first groove 211 has a first end and a second end. In this embodiment, the tapered guide tube 2 is sleeved on the auxiliary tube 3, and the step of the tapered guide tube 2 is correspondingly positioned on the periphery of the starting end. That is, the installation position of the auxiliary tube 3 is set at the maximum cross-section of the tapered guide tube 2, ensuring the structural reliability of this part of the tapered guide tube 2 with the maximum wall thickness. The second groove 212 extends to the periphery of the proximal section 31. The first groove 211 connects to the second groove 212, which extends outward at an angle corresponding to the periphery of the proximal section 31. The second end stops at half the length of the proximal section 31, preserving as much wall thickness of the tapered guide tube 2 as possible at the auxiliary tube 3.

[0055] The first groove 211 can be tilted outward by 20° to 60° relative to the sheath core tube 1. For smoother discharge of physiological saline, a tilt angle of 30° to 45° is preferred.

[0056] The wall thickness of the tapered guide tube at the first end of the flow guide groove is about 0.3mm±0.1mm, the wall thickness at the second end is 0.5mm±0.1mm, and the thickest wall thickness in the middle can reach 0.6mm±0.1mm. This wall thickness is equivalent to the distance between the bottom of the flow guide groove and the near end section.

[0057] In one embodiment, such as Figures 1 to 3 As shown, the tapered guide tube 2 also includes a second tapered tube section 24 connected to the straight tube section 23 away from the first tapered tube section 22; the outer diameter of the second tapered tube section 24 gradually decreases from the end closer to the straight tube section 23 toward the end away from the straight tube section 23. In this embodiment, the design of the second tapered tube section 24 can serve as a guide when the delivery catheter mechanism is withdrawn from the blood vessel.

[0058] In one embodiment, such as Figure 1 and Figure 3 As shown, the tapered guide tube 2 has an inner hole, which includes a coaxially connected tapered section 25 and a straight section 26. A proximal section 31 is installed in the tapered section 25, and the outer wall of the proximal section 31 abuts against the inner wall of the tapered section 25. A distal section 32 is installed in the straight section 26, and the outer wall of the distal section 32 abuts against the inner wall of the straight section 26. During the manufacturing process of the sheath tube, the auxiliary tube 3 is first bonded to the head of the sheath core tube 1. Then, the bonded auxiliary tube 3 and sheath core tube 1 are placed in an injection mold, and the injection molding material fills the mold, forming the structure of the tapered guide tube 2 of this application. Therefore, the tapered guide tube 2 can be more tightly connected to the sheath core tube 1 and the auxiliary tube 3.

[0059] Understandably, the first tapered tube segment 22 is fitted onto the proximal segment 31 through the tapered hole segment 25, and onto the distal segment 32 through the straight hole segment 26. In this embodiment, the second groove 212 is disposed on the outer wall of the first tapered tube segment 22 corresponding to the tapered hole segment 25. Thus, the design of the tapered hole segment 25 further ensures that the first tapered tube segment 22 where the second groove 212 is located has sufficient wall thickness, making it difficult for the second groove 212 to penetrate the tapered guide tube 2.

[0060] In one embodiment, such as Figure 1 and Figure 2 As shown, the width of the guide groove 21 gradually increases from the end closest to the axis of the tapered guide tube 2 toward the end furthest from the axis of the tapered guide tube 2. Understandably, the cross-section of the guide groove 21 has an outward V-shape, that is, the width of the bottom of the guide groove 21 is smaller than the width of the top opening, so that the saline solution inside the catheter assembly can be discharged more easily and quickly through the guide groove 21.

[0061] Another embodiment of the present invention provides a stent delivery device, including an outer sheath (not shown) and the above-described delivery conduit mechanism; the outer sheath is sleeved on the sheath core tube 1 and the tapered guide tube 2.

[0062] Understandably, the maximum cross-section (step) of the tapered guide tube 2 abuts against the inner wall of the outer sheath, limiting the outer sheath. During the cleaning process of the delivery guide mechanism inside the outer sheath, the saline solution at the outer end of the delivery guide mechanism can flow to the distal end and be discharged through the guide groove 21. Moreover, the oblique design of the first groove 211 allows the saline solution to flow obliquely outward along the axial direction of the sheath core tube, which accelerates the saline solution discharge speed to a certain extent. The delivery catheter mechanism of this embodiment can be used alone in interventional procedures. For example, it can be deployed in complex and tortuous vascular segments that are difficult to pass through with general catheters or guidewires to establish an interventional channel. It can also be used in conjunction with other catheter components, such as combined with the outer sheath to form a stent delivery catheter assembly for stent delivery and release.

[0063] In summary, the delivery catheter mechanism of the present invention shortens the flow-guiding groove 21 on the tapered guide tube 2, positioning it proximal to the tapered guide tube 2 and offset from the distal end of the sheath core tube 1. This prevents the distal end of the tapered guide tube 2, which has a smaller outer diameter, from being punctured by the sheath core tube 1 through the flow-guiding groove 21. Furthermore, by reducing the outer diameter of the auxiliary tube 3, the wall thickness of the tapered guide tube 2 surrounding the auxiliary tube 3 is increased without increasing the size of the tapered guide tube 2. This makes it less likely for the flow-guiding groove 21 to penetrate the tapered guide tube 2 when it is opened, thus preventing the sheath core tube 1 from being exposed and ensuring the safety of the delivery catheter mechanism during intravascular delivery. In addition, the tapered guide tube 2 surrounding the auxiliary tube 3 has sufficient wall thickness, ensuring the strength of the tapered guide tube 2.

[0064] The above are merely embodiments of the delivery conduit mechanism and support delivery device of the present invention, and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A delivery conduit mechanism, characterized in that, It includes a sheath core tube and a tapered guide tube, wherein the tapered guide tube is sleeved on the distal end of the sheath core tube and extends beyond the distal end of the sheath core tube, and the outer diameter of the tapered guide tube gradually decreases in the direction away from the distal end of the sheath core tube; The outer wall of the tapered guide tube is provided with a flow guiding groove, which is located on the proximal side of the tapered guide tube relative to the distal end of the sheath core tube and is spaced apart from the distal end of the sheath core tube.

2. The delivery conduit mechanism according to claim 1, characterized in that, It also includes an auxiliary tube, which is sleeved on the distal end of the sheath core tube and is sleeved by the tapered guide tube. The auxiliary tube is located on the distal side of the flow guiding groove. The auxiliary tube includes a proximal section and a distal section arranged coaxially. At least part of the flow guiding groove is disposed on the outer wall of the tapered guide tube sleeved on the proximal section.

3. The delivery conduit mechanism according to claim 2, characterized in that, The tapered guide tube includes a first tapered tube section and a straight tube section arranged coaxially. From one end closer to the straight tube section toward the end farther away from the straight tube section, the outer diameter of the first tapered tube section gradually decreases. The straight tube section is sleeved on the sheath core tube, and the first tapered tube section is sleeved on the auxiliary tube. The flow guiding groove includes a first groove, which is disposed on the outer wall of the first tapered tube section.

4. The delivery conduit mechanism according to claim 3, characterized in that, The flow guiding groove also includes a second groove communicating with the first groove, and the second groove is disposed on the outer wall of the straight pipe section sleeved on the sheath core tube.

5. The delivery conduit mechanism according to claim 4, characterized in that, The bottom wall of the first groove is an inclined wall, and the distance between the inclined wall and the axis of the tapered guide tube gradually increases from the end closer to the second groove to the end farther away from the second groove.

6. The delivery conduit mechanism according to claim 2, characterized in that, The outer diameter of the proximal segment gradually decreases from the end closest to the distal segment toward the end furthest from the distal segment.

7. The delivery conduit mechanism according to claim 2, characterized in that, The outer wall of the distal section is provided with a plurality of helical teeth spaced apart, and the distance between the helical teeth and the axis of the auxiliary tube gradually decreases from the end closer to the proximal section toward the end farther away from the proximal section.

8. The delivery conduit mechanism according to claim 2, characterized in that, The tapered guide tube has an inner hole, which includes a tapered section and a straight section that are coaxially connected. The proximal section is installed in the tapered section, and the outer wall of the proximal section abuts against the inner wall of the tapered section. The distal section is installed in the straight section, and the outer wall of the distal section abuts against the inner wall of the straight section.

9. The delivery conduit mechanism according to claim 3, characterized in that, The length of the first groove is less than two-thirds of the length of the proximal segment.

10. A support conveying device, characterized in that, It includes an outer sheath and a delivery catheter mechanism as described in any one of claims 1 to 9, wherein the outer sheath is sleeved on the sheath core tube and the tapered guide tube.

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