A guidewire catheter exchange vascular interventional device

Abstract

The present invention discloses a guidewire-catheter exchange vascular interventional device, comprising a guide sheath assembly, a puncture needle, a guidewire and a catheter, and belongs to the field of medical devices. The guide sheath assembly is composed of an outer sheath tube and an expansion tube, and the outer sheath tube and the distal end of the expansion tube have a gradient transition structure, which can reduce the puncture resistance; the proximal end of the outer sheath tube is provided with an exchange joint, and the interior has an asymmetric structure, which increases the blood flow resistance. When it is working, through the cooperation of various components, the catheter is delivered during the withdrawal of the expansion tube, and the tearable sheath is blocked in advance to reduce intraoperative bleeding. The present invention also provides a preparation method for a tearable sheath tube, which can adjust the axial compressive strength, tearability and surface smoothness of the tearable sheath tube by controlling the raw material ratio, molecular weight and processing technology, providing thrust for clinical puncture and reducing puncture resistance; the tearable sheath tube can reduce catheter displacement after the catheter is placed; the expansion tube, guidewire and catheter are provided with marking points to facilitate medical operation.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and in particular to a guidewire catheter exchange vascular interventional device. Background Art

[0002] In intravenous infusion therapy, it is common to insert an intravascular interventional device through a catheter sheath. Traditional catheter sheaths usually have only one entrance, and the operation process is as follows: after the puncture needle punctures the blood vessel, a guide wire is introduced, and the dilator tube and catheter sheath are sent along the guide wire. The dilator tube and guide wire are then completely pulled out, and then the target device is inserted through the entrance of the catheter sheath. There are obvious defects in this process: when the dilator tube and guide wire are pulled out of the catheter sheath, the pressure in the blood vessel will cause a large amount of venous blood to flow out along the entrance of the catheter sheath, which will not only cause blood loss to the patient and increase the difficulty of operation for medical staff, but may also cause infection risks. Therefore, it is necessary to design a catheter sheath that prevents backflow of blood.

[0003] In the prior art, patent CN118987455B proposes an anti-reflux catheter sheath, which is provided with a sealing rubber gasket and an end cap. The sealing rubber gasket can automatically close the guidewire through-hole to keep the cavity sealed when the instrument passes through; the end cap further strengthens the seal, effectively preventing blood from flowing out of the handle end, and reducing the risk of intraoperative bleeding. Patent CN117257424B proposes a tearable catheter sheath, which forms a seal by a sealing rubber gasket in the sheath seat to prevent blood backflow. Although the above patents can reduce intraoperative bleeding by adding an elastic sealing valve, the installation combination structure of the sealing gasket and the catheter sheath is complex, the anti-backflow effect of the sealing component is seriously affected by the aging of the component, and the resistance problem caused by the sealing component to the subsequent catheterization process cannot be avoided. Therefore, it is necessary to design a simple, anti-backflow catheter sheath.

[0004] This invention provides a guidewire-catheter exchange vascular interventional device. Through a simple exchange connector structure, the catheter and dilator function as occluders, thereby reducing bleeding during interventional procedures. The exchange mechanism also incorporates an asymmetric internal structure, increasing blood flow resistance and saving time. Furthermore, the invention reduces puncture resistance through the gradient transition between the tearable sheath and dilator. Furthermore, through adjustments to the PTFE tubing formulation and process, a smooth, tearable PTFE tubing is achieved that is easy to tear and resistant to bending. Summary of the Invention

[0005] In view of the deficiencies in the prior art, the present invention provides a guidewire catheter exchange vascular interventional device, which has the functions of smooth puncture, preventing intraoperative bleeding, and reducing puncture resistance.

[0006] To achieve the above-mentioned purpose, the technical solution adopted by the present invention to solve the technical problem is:

[0007] A guidewire catheter exchange vascular interventional device, characterized in that: it includes a catheter sheath assembly, a puncture needle, a guidewire and a catheter; the catheter sheath assembly includes an outer sheath tube and an expansion tube; the outer sheath tube and the expansion tube are interference fit; the outer sheath tube is composed of an exchange joint and a tearable sheath tube, one end of the tearable sheath tube is connected to the exchange joint, and the other end has a gradient transition structure; the interior of the exchange joint has an asymmetric structure; the expansion tube is composed of a seat, a first position identification point of the expansion tube, a second position identification point of the expansion tube and a support rod; one end of the support rod is connected to the seat, and the other end has a gradient transition structure ; The gradient transition structure is one of a primary transition structure and a multi-stage transition structure, the primary transition structure is one of an elliptical arc body of revolution, a parabolic body of revolution, a right-angled trapezoidal body of revolution, a pointed cone and a hemisphere; the multi-stage transition structure is any two or more combinations of an elliptical arc body of revolution, a parabolic body of revolution, a right-angled trapezoidal body of revolution, a pointed cone and a hemisphere; the tearable sheath is a low-friction polytetrafluoroethylene tube that is axially tearable and has high compressive strength, the axial compressive strength of the tearable sheath is 25~30MPa, the axial tear strength is 2~10 N / mm, and the dynamic friction coefficient is ≤0.08;

[0008] Furthermore, the guidewire is provided with at least one guidewire position identification point; the catheter surface has a plurality of common distance identification points and one special distance identification point, and the special distance identification point is marked with a pattern different from the common distance identification points;

[0009] Furthermore, one end of the guidewire is a soft end and the other end is a hard end, and the distance between the guidewire position identification point and the hard end is the same as the total length of the expansion tube; the first position identification point of the expansion tube and the second position identification point of the expansion tube are located on the surface of the support rod and are distinguished by different patterns; the first position identification point of the expansion tube is at a distance L1 from the proximal end of the gradient transition structure of the expansion tube, and the second position identification point of the expansion tube is at a distance L2 from the distal end of the gradient transition structure of the expansion tube. The surface of the catheter has multiple ordinary distance identification points and one special distance identification point, and the special distance identification point is marked with a pattern different from the ordinary distance identification point, and the distance between the special distance identification point and the distal end of the catheter is L 3；

[0010] Preferably, the first position marking point of the expansion tube, the second position marking point of the expansion tube and the guide wire position marking point are closed figures in the radial direction, so that medical staff can observe them at any angle;

[0011] Furthermore, the exchange connector has three ports, which are connected to each other by a Y-shaped channel. The intersection point of the three port axes is O; port 1 is connected to the tearable sheath, and there is an angle α between port 2 and port 3, with a value range of 10-45°. The distance between the proximal end of port 2 and point O is L1, and the distance between the proximal end of port 3 and point O is L 3；

[0012] Furthermore, the intersection point of port 2 and port 3 is point P, and the distance between point P and the proximal end of port 2 is L. 2；

[0013] Furthermore, the port 3 is provided with a handle on a side away from the port 2, and the outer surfaces of the handle and the port 2 are provided with anti-slip grooves;

[0014] Furthermore, the tearable sheath formula is composed of the following percentages of raw materials: high molecular weight polytetrafluoroethylene resin: low molecular weight polytetrafluoroethylene powder: chopped fiber: flaky mica powder: molybdenum disulfide: methyl silicone oil: barium sulfate = (65%~75%): (10%~15%): (5%~8%): (3%~5%): (5%~8%): (0.5%~1%): (0.5%~1%); the molecular weight of the high molecular weight polytetrafluoroethylene resin is 5×10 6 ~1×10 7 The molecular weight of the low molecular weight polytetrafluoroethylene powder is 1×10 5 ~1×10 6 The chopped fibers have a length of 0.5 to 1 mm and a diameter of 5 to 10 μm, the particle size of the flaky mica powder is 5 to 10 μm, the average particle size of the molybdenum disulfide is 1 to 5 μm, and the particle size of the barium sulfate is 50 to 100 nm;

[0015] Furthermore, the production process of the tearable sheath is as follows:

[0016] (1) The chopped fibers and mica sheets were calcined at 510 °C for 2 h to remove organic matter adsorbed on the surface;

[0017] Then, the chopped fibers and mica sheets were immersed in an ethanol-water solution of a silane coupling agent for 20 minutes, and then dried at 120°C for 2 hours. The silane coupling agent was KH-550, and the mass ratio of KH-550: ethanol: water was 3:30:67.

[0018] (2) Add high molecular weight polytetrafluoroethylene resin, low molecular weight polytetrafluoroethylene powder, chopped fibers, flaky mica powder, molybdenum disulfide, methyl silicone oil, and barium sulfate into a high-speed mixer and mix at 100°C for 60 minutes;

[0019] (3) Add the mixed material into the segmented mold, apply 15-20 MPa pressure in the axial direction and 8-10 MPa pressure in the radial direction, and maintain the pressure for 10-15 minutes;

[0020] (4) Heat the preform to 340-390°C and keep it warm for 2-3 hours; adopt a gradient cooling method combining natural cooling and water cooling: first cool it naturally for 10-20 minutes, then immerse it in 4°C water and cool it to room temperature;

[0021] (6) The pipe is axially stretched to a strain of 5% to 8%, and then subjected to stress release treatment at 150 to 200 °C for 1 to 2 hours;

[0022] Furthermore, the temperature of the segmented mold is 180~220℃;

[0023] Furthermore, the outer surfaces of the port 1 and the port 3 have deconstruction grooves, which are two axisymmetric non-penetrating continuous grooves;

[0024] Furthermore, the asymmetric structure is formed by linearly arranging asymmetric units, wherein the asymmetric units are a planar structure or a three-dimensional structure, and the spacing between the asymmetric units is D1, which ranges from 300 to 3000 μm;

[0025] Furthermore, the planar structure is one of a scale structure, a swastika-like structure, and a right-angled trapezoid; the three-dimensional structure is one of a triangular prism and a quadrangular prism;

[0026] Furthermore, the planar structure has a width of D, a length of L, and a line width of D2; the three-dimensional structure has a width of D, a length of L, and a height of H; the value range of D is 40-2000 μm, the value range of L is 300-3000 μm, the value range of D2 is 4-20 μm, and the value range of H is 20-200 μm;

[0027] Furthermore, the asymmetric structure is formed by one of integral molding and secondary processing, the integral molding is one of injection molding or compression molding, and the secondary processing can be one of machining and laser engraving;

[0028] Furthermore, the catheter may be any other interventional instrument.

[0029] How it works

[0030] 1. Insertion of the catheter sheath by puncture: The soft end of the guidewire is introduced into the blood vessel through the puncture needle, and the catheter sheath (the expansion tube is assembled with the outer sheath through port 2) is delivered into the blood vessel along the guidewire. The gradient transition structure design and the interference fit between the expansion tube and the outer sheath ensure the sealing and smoothness of the insertion process;

[0031] 2. Withdraw the dilator and guidewire: Withdraw the guidewire and dilator until the first position mark of the dilator and the guidewire position mark can just be seen. At this time, the dilator and guidewire still have a blocking effect on the tearable sheath to prevent blood from flowing out.

[0032] 3. Catheter pre-blocking: The catheter is inserted into the outer sheath from port 3 until it contacts the dilator tube. At this point, the catheter completes the blocking of port 3.

[0033] 4. Withdraw the dilator and guidewire 2: Withdraw the guidewire and dilator until the second position mark of the dilator is just visible. At this time, some blood will enter the exchange connector, but the asymmetric structure of the conversion connector will hinder it and the speed will be slow.

[0034] Then continue to push the catheter through port 3 to the special distance mark point of the catheter and enter port 3, so that the catheter completes the occlusion of the tearable sheath, and then quickly remove the dilator and guide wire;

[0035] 5. Catheter placement: Continue to advance the catheter to the desired location;

[0036] 6. Sheath removal: Hold the handle and port 2, tear the exchange connector into two halves along the deconstruction groove, and then tear the tearable sheath to remove the outer sheath and keep the catheter in the blood vessel.

[0037] The present invention has the following beneficial effects.

[0038] 1. Reduce blood reflux: The shape design of the exchange connector allows the catheter and the dilator to be placed in the outer sheath at the same time, allowing the catheter to be inserted during the process of withdrawing the dilator, thereby preventing blood from flowing out of the body with the dilator. In addition, the asymmetric structure inside the exchange connector increases the resistance to blood reflux that needs to flow along the gap between the asymmetric units, providing convenience for the exchange operation.

[0039] 2. Reduced puncture resistance: The gradient transition design between the dilator and the outer sheath increases the puncture capability of the catheter sheath and reduces resistance during the puncture process. The interference fit design reduces resistance during the transition between the dilator and the outer sheath, making the puncture process smoother.

[0040] 3. Increased operational convenience: The present invention provides marking points on the dilation tube, guidewire, and catheter. During use, medical staff can simply observe whether the catheter is pulled out or inserted into the puncture point to determine whether the procedure is performed properly, reducing the risks that may be caused by experience-based judgment.

[0041] 4. Tearability: The macromolecules of polytetrafluoroethylene have self-lubricating and highly crystalline properties, making the surface of the pipe smooth and having a certain compressive capacity. Under the environment of heating and pressurization, the polytetrafluoroethylene molecular chains and short-cut fibers are distributed along the pressure direction, further ensuring the axial compressive resistance of the pipe; low-molecular-weight polytetrafluoroethylene micropowder and flaky mica powder are filled in the gaps between the macromolecular chains, reducing the intermolecular force and introducing weak axial interfaces, making the material have axial tearability; the layered crystal structure of molybdenum disulfide slips on the friction surface, forming an interface with low shear strength; methyl silicone oil volatilizes during high-temperature sintering to generate micropores, reducing the entanglement between molecular chains and increasing the smoothness during tearing. In addition, deconstruction grooves are provided on the outer surfaces of the exchange joint ports 3 and port 1, and the deconstruction grooves extend all the way to the junction with the tearable pipe. This can completely split the outer sheath tube, facilitating the rapid removal of the outer sheath tube after the operation, reducing blood vessel irritation, and reducing the risk of catheter displacement. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 is a schematic structural diagram of a catheter sheath assembly;

[0043] Figure 2 is a sectional view of the process of exchanging a guide wire and a catheter;

[0044] Figure 3 is a schematic diagram of retracting the dilator and the guide wire to the first position marking point of the dilator and the position marking point of the guide wire and pre-blocking the catheter;

[0045] Figure 4 Retract the dilator and the guide wire to the second position marking point of the dilator, and the schematic diagram of the catheter blocking the tearable sheath tube;

[0046] Figure 5 Schematic diagram of the asymmetric unit on the inner surface of the exchange joint, where Figure 5 (a) is a schematic diagram of a scale structure; Figure 5 (b) is a schematic diagram of a structure similar to "卍"; Figure 5 (c) is a schematic diagram of a right trapezoid, Figure 5 (a), Figure 5 (b) and Figure 5 (c) are all planar structures; [[ID=3​​​​​​​​​​(d) is a pointed cone first-level transition structure; Figure 7 (e) is a hemispherical first-level transition structure;

[0049] Figure 8 Schematic diagram of the multi-stage transition structure of the outer sheath and dilation tube, Figure 8 (a) is a multi-stage transition structure of pointed cone and elliptical arc rotation body; Figure 8 (b) is a multi-stage transition structure of pointed cone, right-angled trapezoid and elliptical arc rotation; Figure 8 (c) A multi-stage transition structure of pointed cone, right-angled trapezoid and parabola of revolution; Figure 8 (d) is a multi-stage transition structure of an elliptical arc parabola rotation body;

[0050] Figures 1-4 Middle: 1 Outer sheath; 1.1 Tearable tubing; 1.2 Interchange connector; 1.2.1 First port; 1.2.2 Second port; 1.2.3 Third port; 1.2.4 Handle; 1.2.5 Deconstruction slot; 2 Dilation tube; 2.1 Support rod; 2.2 Seat; 2.3 Dilation tube second position mark; 2.4 Dilation tube first position mark; 3 Guidewire; 4 Catheter; 4.1 Special distance mark; 5 Guidewire; 5.1 Guidewire position mark. DETAILED DESCRIPTION

[0051] In order to more clearly describe the purpose, technical methods and advantages of the present invention, the following Figure 1-8 The present invention is described in detail with reference to the accompanying drawings and embodiments. It should be noted that the drawings are all in a very simplified form and are not in precise proportions, and are only used to conveniently and clearly assist in illustrating the embodiments of the present invention. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. Based on the embodiments of the present invention, all other implementation methods obtained by those of ordinary skill in the art without making creative work are within the scope of protection of the present invention. Unless otherwise specified, the reagents used in the embodiments of the present invention are all common commercially available products, and the "distal end" and "proximal end" are expressed relative to the operator.

[0052] A guidewire catheter exchange vascular interventional device, characterized in that: it includes a catheter sheath assembly, a puncture needle, a guidewire and a catheter; the catheter sheath assembly includes an outer sheath tube and an expansion tube; the outer sheath tube and the expansion tube are interference fit; the outer sheath tube is composed of an exchange joint and a tearable sheath tube, one end of the tearable sheath tube is connected to the exchange joint, and the other end has a gradient transition structure; the interior of the exchange joint has an asymmetric structure; the expansion tube is composed of a seat, a first position identification point of the expansion tube, a second position identification point of the expansion tube and a support rod; one end of the support rod is connected to the seat, and the other end has a gradient transition structure ; The gradient transition structure is one of a primary transition structure and a multi-stage transition structure, and the primary transition structure is one of an elliptical arc rotation body, a parabolic rotation body, a right-angled trapezoidal rotation body, a pointed cone and a hemisphere; the multi-stage transition structure is any two or more combinations of an elliptical arc rotation body, a parabolic rotation body, a right-angled trapezoidal rotation body, a pointed cone and a hemisphere; the tearable sheath is a low-friction polytetrafluoroethylene tube that is axially tearable and has high compressive strength. The axial compressive strength of the tearable sheath is 25~30MPa, the axial tear strength is 2~10 N / mm, and the dynamic friction coefficient is ≤0.08.

[0053] Furthermore, the guidewire is provided with at least one guidewire position identification point; the catheter surface has a plurality of common distance identification points and one special distance identification point, and the special distance identification point is identified by a pattern different from the common distance identification points.

[0054] Furthermore, the guidewire has a soft tip at one end and a hard tip at the other, and the distance between the guidewire position marking point and the hard tip is the same as the total length of the expansion tube; the first and second position marking points of the expansion tube are located on the surface of the support rod and are distinguished by different patterns; the first position marking point of the expansion tube is at a distance L1 from the proximal end of the gradient transition structure of the expansion tube, and the second position marking point of the expansion tube is at a distance L2 from the distal end of the gradient transition structure of the expansion tube. The surface of the catheter has multiple ordinary distance marking points and one special distance marking point, the special distance marking point is marked with a pattern different from the ordinary distance marking points, and the special distance marking point is at a distance L3 from the distal end of the catheter.

[0055] Preferably, the first position marking point of the expansion tube, the second position marking point of the expansion tube and the guide wire position marking point are closed figures in the radial direction, so that medical staff can observe them at any angle.

[0056] Furthermore, the exchange connector has three ports, which are connected internally by a Y-shaped channel, and the intersection point of the axes of the three ports is O; port 1 is connected to the tearable sheath, and there is an angle α between port 2 and port 3, with a value range of 10-45°, the distance between the proximal end of port 2 and point O is L1, and the distance between the proximal end of port 3 and point O is L3.

[0057] Furthermore, the internal intersection point of port 2 and port 3 is point P, and the distance between point P and the proximal end of port 2 is L2.

[0058] Furthermore, the port 3 is provided with a handle on a side away from the port 2 , and the outer surfaces of the handle and the port 2 are provided with anti-slip grooves.

[0059] Furthermore, the outer surfaces of the port 1 and the port 3 have deconstruction grooves, and the deconstruction grooves are two axially symmetrical non-penetrating continuous grooves.

[0060] Furthermore, the asymmetric structure is formed by linearly arranging asymmetric units, and the asymmetric units are a planar structure or a three-dimensional structure, and the spacing between the asymmetric units is D1, which ranges from 300 to 3000 μm.

[0061] Furthermore, the planar structure is one of a scale structure, a swastika-like structure and a right-angled trapezoid; the three-dimensional structure is one of a triangular prism and a quadrangular prism.

[0062] Furthermore, the planar structure has a width of D, a length of L, and a line width of D2; the three-dimensional structure has a width of D, a length of L, and a height of H; the value range of D is 40-2000μm, the value range of L is 300-3000μm, the value range of D2 is 4-20μm, and the value range of H is 20-200μm.

[0063] Furthermore, the outer sheath is prepared by the following process:

[0064] (1) Prepare the raw materials in the following ratios: high molecular weight polytetrafluoroethylene resin: low molecular weight polytetrafluoroethylene powder: chopped fiber: flaky mica powder: molybdenum disulfide: methyl silicone oil: barium sulfate = (65%~75%): (10%~15%): (5%~8%): (3%~5%): (5%~8%): (0.5%~1%): (0.5%~1%); the molecular weight of the high molecular weight polytetrafluoroethylene resin is 5×10 6 ~1×10 7 The molecular weight of the low molecular weight polytetrafluoroethylene powder is 1×10 5 ~1×10 6 The chopped fibers have a length of 0.5 to 1 mm and a diameter of 5 to 10 μm, the particle size of the flaky mica powder is 5 to 10 μm, the average particle size of the molybdenum disulfide is 1 to 5 μm, and the particle size of the barium sulfate is 50 to 100 nm;

[0065] (2) The chopped fibers and mica sheets were calcined at 510 °C for 2 h to remove organic matter adsorbed on the surface;

[0066] Then, the chopped fibers and mica sheets were immersed in an ethanol-water solution of a silane coupling agent for 20 minutes, and then dried at 120°C for 2 hours. The silane coupling agent was KH-550, and the mass ratio of KH-550: ethanol: water was 3:30:67.

[0067] (3) Add high molecular weight polytetrafluoroethylene resin, low molecular weight polytetrafluoroethylene powder, chopped fibers, flaky mica powder, molybdenum disulfide, methyl silicone oil, and barium sulfate into a high-speed mixer and mix at 100°C for 60 minutes;

[0068] (4) Add the mixed material into the segmented mold at a temperature of 180-220°C, apply a pressure of 15-20 MPa in the axial direction and 8-10 MPa in the radial direction, and maintain the pressure for 10-15 minutes;

[0069] (5) Heat the preform to 340-390°C and keep it warm for 2-3 hours;

[0070] (6) Allow to cool naturally for 10 to 20 minutes, then immerse in 4°C water to cool to room temperature;

[0071] (7) The pipe is axially stretched to a strain of 5% to 8%, and then subjected to stress release treatment at 150 to 200 °C for 1 to 2 hours to obtain a pipe of the required size;

[0072] (8) The interchange joint is connected to the tearable sheath by injection molding, molding or bonding, and the asymmetric structure inside the interchange joint is formed by one of one-piece molding and secondary processing, wherein the one-piece molding is one of injection molding or molding, and the secondary processing can be one of machining and laser engraving.

[0073] Here is an explanation of how to use the device:

[0074] 1. Insertion of the catheter sheath by puncture: The soft end of the guidewire is introduced into the blood vessel through the puncture needle, and the catheter sheath (the expansion tube is assembled with the outer sheath through port 2) is delivered into the blood vessel along the guidewire. The gradient transition structure design and the interference fit between the expansion tube and the outer sheath ensure the sealing and smoothness of the insertion process;

[0075] 2. Withdraw the dilator and guidewire: Withdraw the guidewire and dilator until the first position mark of the dilator and the guidewire position mark can just be seen. At this time, the dilator and guidewire still have a blocking effect on the tearable sheath to prevent blood from flowing out.

[0076] 3. Catheter pre-blocking: The catheter is inserted into the outer sheath from port 3 until it contacts the dilator tube. At this point, the catheter completes the blocking of port 3.

[0077] 4. Withdraw the dilator and guidewire 2: Withdraw the guidewire and dilator until the second position mark on the dilator is just visible. At this time, some blood will enter the exchange connector, but the asymmetric structure of the conversion connector will hinder the speed. Then continue to advance the catheter through port 3 to the special distance mark on the catheter and enter port 3, so that the catheter completes the occlusion of the tearable sheath, and then quickly remove the dilator and guidewire;

[0078] 5. Catheter placement: Continue to advance the catheter to the desired location;

[0079] 6. Sheath removal: Hold the handle and port 2, tear the exchange connector into two halves along the deconstruction groove, and then tear the tearable sheath to remove the outer sheath and keep the catheter in the blood vessel.

[0080] Example 1

[0081] This embodiment provides a guidewire-catheter exchange vascular interventional device, comprising a catheter sheath assembly, a puncture needle, a guidewire, and a catheter.

[0082] The catheter sheath assembly is composed of an outer sheath tube and a dilator tube. The outer sheath tube is composed of an exchange connector and a tearable sheath tube;

[0083] The exchange connector has three ports, which are connected internally by a Y-shaped channel, and the intersection point of the axes of the three ports is O; port 1 is connected to the tearable sheath by injection molding, the angle α between port 2 and port 3 is 15°, the distance between the proximal end of port 2 and point O is L1=30mm, and the distance between port 3 and point O is L3=25mm. The internal intersection point of port 2 and port 3 is point P, and the distance between point P and the proximal end of port 2 is L2. Port 3 is provided with a handle on the side away from port 2, and the outer surface of the handle and port 2 are provided with anti-slip grooves. The outer surface of port 1 and port 3 has a deconstruction groove, which is two axially symmetrical non-penetrating continuous grooves, and its radial cross-section is conical. The interior of the exchange connector obtains a linearly arranged scale structure by injection molding, such as Figure 5 As shown in (a), the upper end of the image is close to the near end of port 2 and port 3, and the lower end of the image is close to port 1. The spacing D1 is 1500μm, the plane structure width D is 1000μm, the length L is 1500μm, and the line width D2 is 10μm;

[0084] One end of the tearable sheath is connected to the exchange connector port 1, and the other end has a gradient transition structure. The gradient transition structure is a first-level transition structure, specifically an elliptical arc rotation body, such as Figure 7 (a)

[0085] The expansion tube is composed of a seat, a first position mark point of the expansion tube, a second position mark point of the expansion tube and a support rod. One end of the support rod is connected to the seat, and the other end has a multi-stage transition structure of a pointed cone, a right-angled trapezoid and an elliptical arc rotation body adapted to the tearable sheath of the outer sheath, such as Figure 8 As shown in (b), the outer sheath and the expansion tube are interference fit. The first and second position marking points of the expansion tube are located on the surface of the support rod. The first position marking point is a thick circular ring, and the second position marking point is two adjacent thin circular rings. The distance from the first position marking point of the expansion tube to the proximal end of the gradient transition structure of the expansion tube is L1 = 30mm, and the distance from the second position marking point of the expansion tube to the distal end of the gradient transition structure of the expansion tube is L2 = 25mm.

[0086] The guide wire has a soft tip at one end and a hard tip at the other end, and a guide wire position mark is set on the surface. The distance between the guide wire position mark and the hard tip of the guide wire is the same as the total length of the dilation tube, which is 100 mm.

[0087] The surface of the catheter has multiple distance marking points, and also has a special distance marking point. The distance from the special distance marking point to the distal end of the catheter is L3 = 25 mm.

[0088] The preparation method of the tearable sheath is as follows:

[0089] (1) Prepare raw materials in the following ratio: high molecular weight polytetrafluoroethylene resin: low molecular weight polytetrafluoroethylene powder: chopped glass fiber: flaky mica powder: molybdenum disulfide: methyl silicone oil: barium sulfate = 75%: 11%: 5%: 3%: 5%: 0.5%: 0.5%; the molecular weight of the high molecular weight polytetrafluoroethylene resin is 5×10 6 The molecular weight of the low molecular weight polytetrafluoroethylene powder is 1×10 5 The chopped glass fiber has a length of 0.5 mm and a diameter of 5 μm, the particle size of the flaky mica powder is 5 μm, the average particle size of the molybdenum disulfide is 1 μm, and the particle size of the barium sulfate is 50 nm;

[0090] (2) The chopped fibers and mica sheets were calcined at 510 °C for 2 h to remove organic matter adsorbed on the surface;

[0091] Then, the chopped glass fibers and mica sheets were immersed in an ethanol-water solution of a silane coupling agent for 20 minutes, and then dried at 120° C. for 2 hours. The silane coupling agent was KH-550, and the mass ratio of KH-550: ethanol: water was 3:30:67.

[0092] (3) Add high molecular weight polytetrafluoroethylene resin, low molecular weight polytetrafluoroethylene powder, chopped glass fiber, flaky mica powder, molybdenum disulfide, methyl silicone oil and barium sulfate into a high-speed mixer and mix at 100°C for 60 minutes;

[0093] (4) Add the mixed material into the segmented mold at a temperature of 220°C, apply a pressure of 20 MPa in the axial direction and 8 MPa in the radial direction, and maintain the pressure for 15 minutes;

[0094] (5) Heat the preform to 360°C and keep it warm for 2 hours;

[0095] (6) First cool naturally for 15 minutes, then immerse in 4°C water to cool to room temperature to obtain a tube with a smooth surface;

[0096] (7) The tube was axially stretched with a tensile strain of 5%, and then subjected to stress release treatment at 150 °C for 2 h to allow the PTFE macromolecular chains and short glass fibers to be arranged axially again.

[0097] When simulating use in vitro, the following 6 steps are followed:

[0098] Preparation: Skin, muscle and blood vessel simulations, with blood vessels filled with red fluid;

[0099] 1. Insertion of the catheter sheath by puncture: The soft end of the guidewire is introduced into the blood vessel through the puncture needle, and the catheter sheath (the expansion tube is assembled with the outer sheath through port 2) is delivered into the blood vessel along the guidewire. The gradient transition structure design and the interference fit between the expansion tube and the outer sheath ensure the sealing and smoothness of the insertion process;

[0100] 2. Withdraw the dilator and guidewire: Withdraw the guidewire and dilator until the first position mark of the dilator and the guidewire position mark can just be seen. At this time, the dilator and guidewire still have a blocking effect on the tearable sheath to prevent blood from flowing out.

[0101] 3. Catheter pre-blocking: The catheter is inserted into the outer sheath from port 3 until it contacts the dilator tube. At this point, the catheter completes the blocking of port 3.

[0102] 4. Withdraw the dilator and guidewire 2: Withdraw the guidewire and dilator until the second position mark on the dilator is just visible. At this time, some blood will enter the exchange connector, but the asymmetric structure of the conversion connector will hinder the speed. Then continue to advance the catheter through port 3 to the special distance mark on the catheter and enter port 3, so that the catheter completes the occlusion of the tearable sheath, and then quickly remove the dilator and guidewire;

[0103] 5. Catheter placement: Continue to advance the catheter to the desired location;

[0104] 6. Sheath removal: Hold the handle and port 2, tear the exchange connector into two halves along the deconstruction groove, and then tear the tearable sheath to remove the outer sheath, leaving the catheter in the blood vessel;

[0105] Simulation of usage results: The catheter sheath was smoothly inserted, and no liquid flowed out during the exchange with the catheter. The catheter was inserted into port 3 without obvious resistance. When the outer sheath was removed, the outer sheath could be torn, and the tearing process was smooth without burrs or powder, reducing the irritation to blood vessels. At the same time, the dilator with a multi-stage transition structure can better adapt to different blood vessel conditions.

[0106] Example 2

[0107] The wire-catheter exchange vascular interventional device delivery device of this example is basically the same as that of Example 1, except that:

[0108] (1) The gradient transition structure of the tearable sheath is a single-stage transition structure, specifically a hemispherical shape, as shown in Figure 7 (e);

[0109] (2) The gradient transition structure of the dilator is a multi-stage transition structure, specifically an elliptical arc parabolic revoloid, as shown in Figure 8 (d);

[0110] (3) The asymmetric unit of the asymmetric structure inside the exchange joint adopts a planar structure similar to the "卍" structure, with a spacing D1 of 2000μm, a width D of 2000μm, a length L of 2000μm, and a height D2 of 4μm. The asymmetric unit is integrally formed by die pressing;

[0111] (4) The included angle α between port 2 and port 3 is 30°;

[0112] (5) The preparation method of the tearable sheath is as follows:

[0113] a) Prepare raw materials according to the ratio of high molecular weight polytetrafluoroethylene resin: low molecular weight polytetrafluoroethylene fine powder: short carbon fiber: flaky mica powder: molybdenum disulfide: methyl silicone oil: barium sulfate = 70%: 10%: 8%: 3%: 8%: 0.5%: 0.5%. The molecular weight of the high molecular weight polytetrafluoroethylene resin is 1×10 7 , and the molecular weight of the low molecular weight polytetrafluoroethylene fine powder is 1×10 6 . The length of the short carbon fiber is 1mm, the diameter is 10μm, the particle size of the flaky mica powder is 10μm, the average particle size of the molybdenum disulfide is 5μm, and the particle size of the barium sulfate is 100nm;

[0114] b) Add the mixed materials to a segmented mold, with a temperature of 220°C, apply an axial pressure of 20MPa and a radial pressure of 10MPa, and hold the pressure for 15 minutes;

[0115] c) Heat the preformed blank to 370°C and keep it warm for 3 hours;

[0116] d) The tube was axially stretched to a strain of 6%, and then stress-released at 150°C for 2 h to allow the PTFE macromolecular chains and chopped carbon fibers to align axially again.

[0117] Simulated use results showed that the catheter sheath insertion process was smooth, with no fluid leakage during catheter exchange. There was some resistance when the catheter was inserted through port 3. The outer sheath could be torn off smoothly during removal, without burrs or powder, minimizing vascular irritation. Furthermore, the dilator tube with a multi-stage transition structure better accommodates diverse vascular conditions.

[0118] Example 3

[0119] The guidewire catheter exchange vascular interventional device delivery device of this embodiment is basically the same in structure as that of embodiment 1, except that:

[0120] (1) The gradient transition structure of the outer sheath is a multi-level transition structure consisting of a right-angled trapezoidal rotation body and an elliptical arc rotation body;

[0121] (2) The angle α between port 2 and port 3 of the interchange connector is 45°. The distance L1 between the proximal end of port 2 and point O is 50 mm, and the distance L3 between the proximal end of port 3 and point O is 30 mm. The distance L2 between point P and the proximal end of port 2 is 40 mm.

[0122] (3) The asymmetric unit inside the exchange joint is a right-angle trapezoid with a spacing D1 of 300 μm, a plane structure width D of 40 μm, a length L of 300 μm, and a line width D2 of 4 μm. The asymmetric structure is made in one piece by injection molding;

[0123] (4) The gradient transition structure of the expansion tube is adapted to the outer sheath tube and is a parabolic rotation body, such as Figure 7 (b) The distance L1 from the first position mark of the expansion tube to the proximal end of the expansion tube's trapezoidal transition structure is 50 mm. The distance from the guidewire position mark to the hard tip is the same as the total length of the expansion tube, 140 mm. The distance L3 from the special distance mark on the catheter surface to the distal end of the catheter is 30 mm.

[0124] (5) The preparation method of the tearable sheath is as follows:

[0125] a) Prepare raw materials in the following ratio: high molecular weight polytetrafluoroethylene resin: low molecular weight polytetrafluoroethylene powder: chopped fiber: flaky mica powder: molybdenum disulfide: methyl silicone oil: barium sulfate = 65%: 15%: 5%: 5%: 8%: 1%: 1%; the molecular weight of the high molecular weight polytetrafluoroethylene resin is 5×10 6 The molecular weight of the low molecular weight polytetrafluoroethylene powder is 5×105 The chopped glass fiber has a length of 0.8 mm and a diameter of 8 μm, the particle size of the flaky mica powder is 8 μm, the average particle size of the molybdenum disulfide is 3 μm, and the particle size of the barium sulfate is 80 nm;

[0126] b) Add the mixed material into the segmented mold, set the temperature to 180°C, apply 15 MPa pressure in the axial direction and 8 MPa in the radial direction, and maintain the pressure for 10 minutes;

[0127] c) heating the preform to 340°C and keeping the temperature for 2 hours;

[0128] d) The tube was axially stretched to a strain of 8%, and then stress-released at 180°C for 1.5 h to allow the PTFE macromolecular chains and chopped glass fibers to align axially again.

[0129] Results of simulated use: The catheter sheath insertion process was smooth, no liquid flowed out during the exchange with the catheter, there was resistance when the catheter was inserted from port 3, but the catheter could still be pushed; when withdrawing the outer sheath, the outer sheath could be torn off, and the tearing process was smooth, without burrs or powder, reducing irritation to the blood vessels.

[0130] Example 4

[0131] The guidewire catheter exchange vascular interventional device delivery device of this embodiment has a substantially similar structure to that of embodiment 1, except that:

[0132] (1) The gradient transition structure of the tearable sheath is a first-level transition structure of a right-angled trapezoidal rotation body, such as Figure 7 (c);

[0133] (2) The gradient transition structure of the expansion tube is a multi-stage transition structure composed of a pointed cone, a right-angled trapezoid and a parabolic rotation body, such as Figure 8 (c);

[0134] (3) The asymmetric unit of the asymmetric structure inside the exchange joint adopts a three-dimensional triangular prism with a spacing D1 of 3000 μm, a three-dimensional structure width D of 2000 μm, a length L of 3000 μm, and a height H of 80 μm. The asymmetric unit is made by secondary processing of laser engraving;

[0135] (4) The angle α between port 2 and port 3 of the interchange connector is 10°.

[0136] Simulated use results showed that the catheter sheath was smoothly inserted, with no fluid leakage during catheter exchange, and the catheter was advanced through port 3 without noticeable resistance. The outer sheath could be torn off smoothly during removal, without burrs or powder, minimizing vascular irritation. Furthermore, the dilator tube with a multi-stage transition structure better accommodates diverse vascular conditions.

[0137] Example 5

[0138] The guidewire catheter exchange vascular interventional device delivery device of this embodiment has a substantially similar structure to that of embodiment 1, except that:

[0139] (1) The gradient transition structure of the outer sheath is a first-level transition structure with a pointed cone.

[0140] (2) The asymmetric unit of the asymmetric structure inside the exchange joint is a three-dimensional quadrangular prism with a spacing D1 of 3000 μm, a three-dimensional structure width D of 2000 μm, a length L of 3000 μm, and a height H of 200 μm. The asymmetric structure is secondary molded by mechanical processing.

[0141] (3) The trapezoidal transition structure of the expansion tube is a multi-stage transition structure of a pointed cone and an elliptical arc rotation body.

[0142] Results of simulated use: The catheter sheath insertion process was smooth, no liquid flowed out during the exchange with the catheter, and there was no obvious resistance when the catheter exited the port; when withdrawing the outer sheath, the outer sheath could be torn open, and the tearing process was smooth, without burrs or powder, reducing irritation to the blood vessels.

[0143] Example 6

[0144] The guidewire catheter exchange vascular interventional device delivery device of this embodiment has a similar structure to that of embodiment 5, except that:

[0145] (1) The asymmetric unit of the asymmetric structure inside the exchange joint is a three-dimensional quadrangular prism with a spacing D1 of 300 μm, a three-dimensional structure width D of 40 μm, a length L of 300 μm, and a height H of 20 μm. The asymmetric structure is secondary molded by laser engraving.

[0146] Results of simulated use: The catheter sheath insertion process was smooth, no liquid flowed out during the exchange with the catheter, and there was no obvious resistance when the catheter exited the port; when withdrawing the outer sheath, the outer sheath could be torn open, and the tearing process was smooth, without burrs or powder, reducing irritation to the blood vessels.

[0147] Comparative Example 1

[0148] It is basically the same as Example 1, except that:

[0149] (1) The angle α between port 2 and port 3 of the interchange connector is 50°;

[0150] (2) The preparation methods of tearable sheaths are different. The differences are:

[0151] a) Prepare the raw materials in the ratio of high molecular weight polytetrafluoroethylene resin: chopped glass fiber: molybdenum disulfide = 80%: 15%: 5%;

[0152] b) the chopped fibers are mixed without being calcined or treated with a silane coupling agent;

[0153] During the simulated operation, short-cut fibers can be observed on the surface of the tearable sheath tube, which is unevenly distributed. During the catheter placement process, the catheter is difficult to advance due to its large bends. The outer sheath tube conversion joint can be torn apart, but the tearable sheath tube cannot be torn apart.

[0154] Comparative Example 2

[0155] It is basically the same as Example 1, except that:

[0156] (1) The outer sheath is composed of a common connector and a tearable tube;

[0157] (2) The preparation methods of tearable sheaths are different. The differences are:

[0158] a) Add the mixed material into the segmented mold, apply 10 MPa pressure in the axial direction and 10 MPa in the radial direction, and maintain the pressure for 15 minutes;

[0159] b) In step (6), the product is directly immersed in 4°C water and cooled to room temperature without natural cooling;

[0160] c) do not proceed to step (7);

[0161] During the simulated operation, the surface of the outer sheath was smooth and the puncture was smooth, but during the catheterization process, the dilator and guide wire had to be completely withdrawn first, and then the catheter was inserted. During this period, blood would flow out along the outer sheath. When the outer sheath was withdrawn, it could be torn open, but the tearing line was serrated and the axial orientation of the tube was insufficient.

[0162] Comparative Example 3

[0163] It is basically the same as Example 1, except that:

[0164] (1) The interior of the exchange joint is a smooth surface;

[0165] (2) The preparation methods of tearable sheaths are different. The differences are:

[0166] The raw material ratio is: high molecular weight polytetrafluoroethylene resin: low molecular weight polytetrafluoroethylene powder: flaky mica powder: molybdenum disulfide: methyl silicone oil: barium sulfate = 65%: 16%: 5%: 8%: 5%: 1%; the molecular weight of the high molecular weight polytetrafluoroethylene resin is 5×10 5 The molecular weight of the low molecular weight polytetrafluoroethylene powder is 1×10 4 The length of the chopped fibers is 2 mm and the diameter is 50 μm. The particle size of the flaky mica powder is 50 μm. The average particle size of the molybdenum disulfide is 30 μm. The particle size of the barium sulfate is 500 nm.

[0167] During the in vitro simulation, the outer sheath can be torn and bent during puncture, and multiple punctures are required before entry. During the process of pulling out the dilator tube and guide wire, a small amount of liquid will flow out from port 2.

[0168] Test method:

[0169] Sample information: outer diameter 2.5mm, inner diameter 1.9mm;

[0170] Equipment information: Universal material testing machine and ring-block friction testing machine;

[0171] (1) Axial compressive strength: Samples of Examples 1-3 and Comparative Examples 1-3 were taken with 50 mm in length and both ends were polished flat with sandpaper to ensure that the end faces were perpendicular to the axis. The samples were conditioned at room temperature for 48 h and placed on the plane compression fixture of a universal material testing machine. The loading speed was set to 2 mm / min and the samples were compressed until the materials bent. The maximum compressive strength was recorded.

[0172] (2) Axial tear strength: Samples of Examples 1-3 and Comparative Examples 1-3 were taken in lengths of 100 mm and conditioned at room temperature for 48 h. The tubes were cut axially and processed into trouser-shaped specimens using the "trouser tearing method" with a cut length of 40 mm. Upper and lower clamps were used to clamp both sides of the cut, with a clamp spacing of 50 mm. The tensile rate was 50 mm / min, and the universal material testing machine was started until the samples were completely separated. The axial tear strength was recorded.

[0173] (3) Dynamic friction coefficient: The samples of Examples 1-3 and Comparative Examples 1-3 were cut into 100 mm lengths and conditioned at room temperature for 48 h. The pipes were fixed on a testing machine so that the grinding block was in contact with the outer surface of the pipes. The ring-block friction tester was turned on, the normal load N was set to 0.5 MPa, the sliding speed was set to 0.1 m / s, and the test time was 5 to 10 min. The motor was started to make the pipe and the grinding block move relative to each other. The dynamic friction force F was recorded and the dynamic friction coefficient was calculated: μ = F / N.

[0174] The test results are shown in Table 1:

[0175]

[0176] From the results in Table 1, it can be seen that the formula and process of the tearable sheath have a great influence on the performance of the product. Comparative Examples 1-3, Comparative Example 1 and Comparative Example 3 show that high molecular weight polytetrafluoroethylene resin and chopped fibers can provide strength for the pipe; Comparative Examples 1-3 and Comparative Example 1 show that low molecular weight polytetrafluoroethylene powder, flaky mica powder and methyl silicone oil affect the tearability of the product. This is because polytetrafluoroethylene powder and flaky mica powder will be dispersed between the molecular chains of high molecular weight polytetrafluoroethylene, forming an interface to reduce the intermolecular force; methyl silicone oil will form micropores during the sintering process, reducing molecular entanglement. Comparative Example 1 and Comparative Example 2 show that during pre-pressing during processing, non-uniform pressing and the final drawing process can increase the axial compressive strength. This is because non-uniform pressing and drawing can make high molecular weight polytetrafluoroethylene and chopped fibers distributed along the axial direction, increasing the axial compressive strength; Comparative Example 1 and Example 2 show that molybdenum sulfide can improve the surface sliding properties of the material.

[0177] Combining the mechanical property results and simulated usage results of Examples 1-6 and Comparative Examples 1-3, it can be seen that the parameter tearable sheath provided by the present invention has appropriate compressive strength and tearability, and a smooth surface. The gradient transition structure at the distal end of the tearable sheath and the gradient transition structure at the distal end of the expansion tube make puncture smooth, and the design of the exchange joint and the internal asymmetric structure can prevent intraoperative bleeding.

Claims

1. A guidewire-catheter exchange vascular interventional device, characterized by: It includes a catheter sheath assembly, a puncture needle, a guide wire and a catheter; the catheter sheath assembly includes an outer sheath tube and a dilator tube; The outer sheath tube consists of an exchange adapter and a tearable sheath tube. One end of the tearable sheath tube is connected to the exchange adapter, and the other end has a gradient transition structure; the exchange adapter has an asymmetric structure inside; the asymmetric structure is formed by linearly arranging asymmetric units, and the asymmetric unit is one of a planar structure or a three-dimensional structure; the planar structure is one of a scale structure, a structure similar to "卍", and a right trapezoid; the three-dimensional structure is one of a triangular prism and a quadrangular prism; the tearable sheath tube is a low-friction polytetrafluoroethylene tube that can be axially torn and has high compressive strength. The formula of the tearable sheath tube consists of the following raw materials in percentages: high molecular weight polytetrafluoroethylene resin: low molecular weight polytetrafluoroethylene micropowder: short cut fibers: flaky mica powder: molybdenum disulfide: methyl silicone oil: barium sulfate = (65% - 75%): (10% - 15%): (5% - 8%): (3% - 5%): (5% - 8%): (0.5% - 1%): (0.5% - 1%); the axial compressive strength of the tearable sheath tube is 25 - 30 MPa, the axial tearing strength is 2 - 10 N / mm, and the dynamic friction coefficient ≤ 0.08; The dilator tube consists of a seat, a first dilator position marking point, a second dilator position marking point and a support rod; one end of the support rod is connected to the seat, and the other end has a gradient transition structure; The gradient transition structure is one of a first-level transition structure and a multi-level transition structure. The first-level transition structure is one of an elliptical arc of revolution, a parabola of revolution, a right trapezoid of revolution, a pointed cone and a hemisphere; the multi-level transition structure is any combination of two or more of an elliptical arc of revolution, a parabola of revolution, a right trapezoid of revolution, a pointed cone and a hemisphere.

2. The guidewire catheter exchange vascular interventional device according to claim 1, characterized in that: The guide wire has at least 1 guide wire position marking point; the catheter surface has multiple ordinary distance marking points and a special distance marking point, and the special distance marking point is marked with a pattern different from that of the ordinary distance marking points; the first dilator position marking point and the second dilator position marking point are located on the surface of the support rod and are distinguished by different patterns; the distance from the first dilator position marking point to the proximal end of the gradient transition structure of the dilator tube is L₁, and the distance from the second dilator position marking point to the distal end of the gradient transition structure of the dilator tube is L₂.

3. The guidewire catheter exchange vascular interventional device according to claim 1, characterized in that: The exchange adapter has three ports, and the inside is connected by a Y-shaped channel. The intersection point of the axes of the three ports is O; among them, port 1 is connected to the tearable sheath tube, there is an included angle α between port 2 and port 3, and the value range is 15 - 45°. The distance from the proximal end of port 2 to point O is L₁, and the distance from port 3 to point O is L₃.

4. The guidewire catheter exchange vascular interventional device according to claim 1, characterized in that: The molecular weight of the high molecular weight polytetrafluoroethylene resin is 5×10 6 ~1×10 7 The molecular weight of the low molecular weight polytetrafluoroethylene powder is 1×10 5 ~1×10 6 The length of the chopped fibers is 0.5 to 1 mm, the diameter is 5 to 10 μm, the particle size of the flaky mica powder is 5 to 10 μm, the average particle size of the molybdenum disulfide is 1 to 5 μm, and the particle size of the barium sulfate is 50 to 100 nm.

5. The guidewire catheter exchange vascular interventional device according to claim 1, characterized in that: The production process of the tearable sheath tube is as follows: (1) First, calcine the short cut fibers and mica flakes at 510 °C for 2 h to remove the adsorbed organic substances on the surface; Then, soak the short cut fibers and mica flakes in an ethanol aqueous solution of a silane coupling agent for 20 min, and then dry at 120 °C for 2 h; the silane coupling agent is KH-550, and the mass ratio of KH-550: ethanol: water is: 3: 30: 67; (2) adding high molecular weight polytetrafluoroethylene resin, low molecular weight polytetrafluoroethylene powder, chopped fibers, flaky mica powder, molybdenum disulfide, methyl silicone oil, and barium sulfate into a high-speed mixer and mixing at 100° C. for 60 min; (3) Add the mixed material into the segmented mold, apply 15-20 MPa pressure in the axial direction and 8-10 MPa pressure in the radial direction, and maintain the pressure for 10-15 minutes; (4) heating the preform to 340-390°C and keeping the temperature for 2-3 hours; (5) Use a gradient cooling method that combines natural cooling and water cooling: first cool naturally for 10 to 20 minutes, then immerse in 4°C water to cool to room temperature; (6) The pipe is axially stretched to a strain of 5% to 8%, and then subjected to stress release treatment at 150 to 200°C for 1 to 2 hours.

6. The guidewire catheter exchange vascular interventional device according to claim 1, characterized in that: The asymmetric unit is a planar structure or a three-dimensional structure, and the spacing between the asymmetric units is D1, which ranges from 300 to 3000 μm.

7. The guidewire catheter exchange vascular interventional device according to claim 6, characterized in that: The planar structure has a width of D, a length of L, and a line width of D2; the three-dimensional structure has a width of D, a length of L, and a height of H; the range of D is 40-2000 μm, the range of L is 300-3000 μm, the range of D2 is 4-20 μm, and the range of H is 20-200 μm.

8. The guidewire catheter exchange vascular interventional device according to claim 1, characterized in that: The asymmetric structure is formed by integral molding or secondary processing, the integral molding is one of injection molding or compression molding, and the secondary processing is one of machining and laser engraving.

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