Spring stent, stent catheter system and stent implantation method

Abstract

The application relates to the technical field of medical devices, in particular to a spring stent, a stent catheter system and a stent implantation method. The spring stent provided by the application comprises a clockwork spring, the clockwork spring comprises a hollow cylinder which is spirally wound by a memory alloy wire mesh ring, the memory alloy wire mesh is kept flush at both ends of the hollow cylinder, and the side wall of the clockwork spring is a hollow structure. The spring stent can realize self-expansion and expansion in a blood vessel, effectively adhere to the inner wall of the blood vessel, and can elastically deform according to the memory elasticity to follow the contraction and expansion of the blood vessel, so that a good adhesion effect is achieved. In combination with a pushing assembly included in a stent delivery system and a cutting assembly connected to the distal end of the pushing assembly, the diseased part in the blood vessel can be cut during the implantation of the stent, so that the reliability of the stent adhesion is enhanced, and the risk of new thrombosis and neointimal hyperplasia is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of medical devices, in particular to a spring stent, a stent catheter system and a stent implantation method. BACKGROUND

[0002] Vascular stents can be divided into self-expanding and balloon-expandable types according to the way of deployment in the blood vessel. The former can expand in the blood vessel by itself, and the latter has no elasticity and is attached to the blood vessel by balloon expansion to a certain diameter.

[0003] Most of the vascular stents on the market are of the latter type. Currently, most balloon-expandable metal stents only have conventional sizes to choose from, and doctors can only try to predict which size of the stent is suitable for maintaining the patency of the blood vessel. However, everyone's blood vessels are different, and the final result depends entirely on the experience of each doctor.

[0004] Secondly, due to the elasticity of the blood vessel, the inner diameter of the blood vessel wall changes accordingly when the blood vessel contracts and dilates, while the size of the balloon-expandable metal stent is fixed after being supported in the blood vessel. This may cause poor stent apposition, which affects blood flow patterns and arterial healing, leading to an increased risk of new thrombosis and neointimal hyperplasia.

[0005] In addition, when implanting a self-expanding stent, due to the presence of a lesion site on the inner wall of the blood vessel, the outer surface of the self-expanding stent is difficult to completely adhere to the inner wall of the blood vessel, making it difficult to ensure the stability of the implantation of the self-expanding stent in the blood vessel. SUMMARY

[0006] The purpose of the present application is to provide a spring stent, a stent catheter system and a stent implantation method. By using a self-expanding spring stent, the stent is given the function of free zooming, so that the blood vessel can drive the spring stent to zoom freely when it dilates and contracts, maintaining good apposition between the stent and the blood vessel.

[0007] To achieve the above-mentioned purpose, in a first aspect, the present application provides a spring stent, comprising a clockwork spring, the clockwork spring comprising a cylindrical structure, the cylindrical structure comprising a hollow cylinder wound by a memory alloy wire mesh ring, the memory alloy wire mesh being flush at both ends of the hollow cylinder, and the side wall of the clockwork spring being a hollow structure.

[0008] In an optional embodiment, the memory alloy comprises nickel-titanium alloy, and the clockwork spring is made of a rectangular nickel-titanium alloy wire mesh and can zoom in the radial direction of the hollow cylinder.

[0009] In an optional embodiment, the spring comprises a compressed state and an extended state, the hollow cylinder has a diameter of 0.4-5mm in the compressed state, and the hollow cylinder has a diameter of 0.8-10mm in the extended state.

[0010] In a second aspect, the present application provides a stent catheter system, comprising the spring stent according to any one of the preceding embodiments and a stent delivery device, the stent delivery device comprising a catheter and a push assembly telescopically movable relative to the catheter, the push assembly being configured to push the spring stent out of the catheter and implant the spring stent into a blood vessel, and a cutting assembly connected to a distal end of the push assembly, the cutting assembly being configured to cut a lesion site in the blood vessel before the spring stent is implanted.

[0011] In an optional embodiment, the catheter is internally provided with a push-pull tube, the push assembly comprises two limiting discs connected to the push-pull tube, and the spring stent in the compressed state is arranged in the catheter and located between the two limiting discs.

[0012] In an optional embodiment, the push-pull tube is internally provided with a movable rod, the limiting discs comprise a proximal limiting disc and a distal limiting disc, and the cutting assembly comprises a blade connected between the movable rod and the distal limiting disc, the blade being made of nickel-titanium alloy.

[0013] In an optional embodiment, the blade comprises a plurality of prismatic blades, the plurality of prismatic blades are uniformly distributed on a circumferential direction of the distal limiting disc, one end of each prismatic blade is connected to an outer edge of the distal limiting disc, and the other end of each prismatic blade is concentrated and crossed at a distal end of the movable rod.

[0014] In an optional embodiment, the movable rod is movably inserted into the push-pull tube and telescopically movable relative to a distal end opening of the push-pull tube, a sealing ring is arranged between the movable rod and the push-pull tube, and the movable rod comprises a solid nickel-titanium alloy rod.

[0015] In an optional embodiment, a limiting stopper is arranged on an outer wall of the movable rod, the limiting stopper is capable of being clamped with a proximal end opening of the push-pull tube, and a developing ring is arranged on a telescopic part of the movable rod relative to the push-pull tube.

[0016] The push-pull tube comprises a main cavity for the movable rod to move in and a guide wire cavity for a guide wire to pass through, the main cavity penetrates through the entire push-pull tube, and a distal end opening of the guide wire cavity is arranged at a distal end of the push-pull tube.

[0017] In a third aspect, the present application further provides a stent implantation method using the stent catheter system according to the preceding embodiments, comprising the following steps:

[0018] The catheter, the stent delivery device and the spring stent compressed in the catheter are sent to the lesion site along the guide wire;

[0019] The lesion site is cut by the cutting assembly at the distal end of the pushing assembly;

[0020] The spring stent in the compressed state is pushed out of the catheter to radially expand and expand;

[0021] The spring stent expands and adheres to the inner wall of the blood vessel, and self-scales with the contraction and expansion of the blood vessel;

[0022] The catheter and the stent delivery device are withdrawn, and the implantation of the stent is completed.

[0023] Through the spring stent in the form of a clockwork spring in the application, self-expansion and expansion can be achieved in the blood vessel, effective adhesion to the inner wall of the blood vessel can be achieved, and elastic deformation can be achieved according to the memory elasticity to follow the contraction and expansion of the blood vessel, so that good adhesion of the stent to the blood vessel is achieved.

[0024] In combination with the pushing assembly included in the stent delivery system and the cutting assembly connected at the distal end of the pushing assembly, the lesion site in the blood vessel can be cut during the implantation of the stent, so as to enhance the reliability of the adhesion of the stent, and reduce the risk of new thrombosis and neointimal hyperplasia.

[0025] The stent implantation method in the application can reliably push the spring stent out of the catheter by the pushing assembly, so that the spring stent is self-expanded from the compressed state in the catheter to the expanded state in the blood vessel, and the lesion tissue of the lesion site is effectively cut, so as to ensure the reliable implantation of the spring stent in the blood vessel and the stable cooperation with the blood vessel in subsequent application, and greatly improve the medical effect that can be achieved by the existing stent.

[0026] Other features and advantages of the application will be described in detail in the following specific embodiments. BRIEF DESCRIPTION OF DRAWINGS

[0027] In order to more clearly illustrate the technical solutions of the embodiments of the application, the following will briefly introduce the drawings needed to be used in the embodiments. It should be understood that the following drawings only show some embodiments of the application, and therefore should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can also be obtained without creative labor on the basis of these drawings.

[0028] Figure 1 It is a structural schematic diagram of the spring stent in the application in the contracted state;

[0029] Figure 2 It is a structural schematic diagram of the spring stent in the application in the expanded state;

[0030] Figure 3 Fig. 6 is a schematic diagram of a stent catheter system in the present application;

[0031] Figure 4 Fig. 7 is a schematic diagram of a stent catheter system in the present application when cutting a lesion site;

[0032] Figure 5 Fig. 8 is a schematic diagram of a stent catheter system in the present application when pushing a stent;

[0033] Figure 6 Fig. 9 is a schematic diagram of a stent catheter system in the present application when withdrawing;

[0034] Figure 7 Fig. 10 is a schematic diagram of the cooperation between a movable rod and a guide wire and a push-pull tube in the present application.

[0035] Fig. 11 is a schematic diagram of a stent catheter system in the present application.

[0036] 1-spring stent; 11-spring;

[0037] 2-catheter; 21-push-pull tube; 22-movable rod; 23-developing ring; 24-main body cavity; 25-guide wire cavity; 26-sealing ring;

[0038] 3-pushing assembly; 31-near-end limiting disc; 32-far-end limiting disc;

[0039] 4-cutting assembly; 41-blade;

[0040] 5-limiting block;

[0041] 6-blood vessel;

[0042] 7-guide wire. DETAILED DESCRIPTION

[0043] In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are some embodiments of the present application, but not all the embodiments. The components of the embodiments of the present application described and shown in the drawings herein can be arranged and designed in various different configurations.

[0044] In the description of the present application, it should be pointed out that the terms "in", "out" and the like indicate the position or positional relationship based on the position or positional relationship shown in the drawings, or the position or positional relationship commonly placed when the product of the application is used, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the indicated device or element must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first", "second" and the like are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0045] In the description of the present application, it should be pointed out that unless otherwise explicitly specified and limited, the terms "set", "connected" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected, it can be directly connected, or indirectly connected through an intermediate medium, it can be connected inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0046] The spring stent 1 and the stent catheter system in the present application are mainly used for implanting the self-expanding stent in the blood vessel 6, and realizing effective adhesion with the inner wall of the blood vessel 6 through self-memory elasticity, and making the spring stent 1 deform along with the contraction and dilation of the blood vessel 6, so as to enhance the adhesion effect of the stent and the blood vessel 6.

[0047] At the same time, through the memory elasticity of the spring stent 1, it can be more suitable for the blood vessels 6 of different patients, enhance the matching degree of the spring stent 1 and the blood vessel 6, and abandon the uncertainty that the size of the conventional stent is suitable for keeping the blood vessel 6 open, and avoid the subjective factors of the doctor's experience judgment.

[0048] Referring to Figures 1-2 The spring stent 1 in the present application includes a clock spring 11, specifically, the clock spring 11 includes a certain length, and forms a cylindrical structure after bending heat treatment shaping, wherein the cylindrical structure includes a hollow cylinder coiled by a memory alloy wire mesh ring, the spring stent 1 made of the memory alloy wire mesh with memory elasticity has good elasticity and can stretch and contract by itself in the change of the bound space.

[0049] By keeping the memory alloy wire mesh flush at both ends of the hollow cylinder, a stable cylindrical structure of the spring stent 1 can be formed, reliable deformation in radial stretching and contraction is maintained, the elastic memory deformation of the stent and the radial elastic force of the blood vessel 6 are kept consistent, and the spring stent 1 can be deformed synchronously with the blood vessel 6 when the blood vessel 6 dilates and contracts, thereby maintaining good adhesion effect.

[0050] The side wall of the clock spring 11 is a hollow structure, and the surface can be hollowed into various geometric patterns to enhance the plastic deformation effect of the spring stent 1.

[0051] In one specific embodiment, the memory alloy is preferably a nickel-titanium alloy, and the clock spring 11 is made of a rectangular nickel-titanium alloy wire mesh and can be self-retracted along the radial direction of the hollow cylinder. Through this processing form, the spring support 1 can cooperate with the blood vessel 6, and can elastically deform in real time to follow the dilation and contraction of the blood vessel 6, so that the spring support 1 and the blood vessel 6 form a reliable apposition effect.

[0052] In the manufacturing process of the clock spring 11 in this embodiment, the width direction of the rectangular nickel-titanium alloy wire mesh is used as the winding direction, and the length direction constitutes the axial direction of the spring support 1, which can facilitate the deformation of the spring support 1 in the radial direction, and in combination with the manufacturing material of the nickel-titanium alloy, it can ensure the stability and reliability of the memory elasticity of the spring support 1 in the radial direction.

[0053] The clock spring 11 specifically includes a contracted state and an expanded state, and can deform in real time in the catheter 2 during transportation and in the blood vessel 6 after implantation. Preferably, the diameter of the hollow cylinder in the contracted state is 0.4-5mm, and the diameter of the hollow cylinder in the expanded state is 0.8-10mm. It can be well implanted in the arterial blood vessel 6, and can freely follow the change of the dilation and contraction state of the blood vessel 6 to well adhere to the inner wall of the blood vessel 6.

[0054] In combination with Figure 3 Based on the structure of the spring support 1 described above, the present application also provides a stent catheter system for transporting and implanting the spring support 1, which comprises the spring support 1 and a stent delivery device.

[0055] Specifically, the stent delivery device comprises a catheter 2 and a push assembly 3 that can be extended and retracted relative to the distal end of the catheter 2. The spring support 1 can be accommodated in the catheter 2 and implanted in the lesion site of the blood vessel 6 before reaching the lesion site at the distal end of the catheter 2. Further, the spring support 1 can be reliably pushed out of the catheter 2 and implanted in the blood vessel 6 by the push assembly 3, thereby maintaining the effectiveness of the transportation and implantation of the spring support 1.

[0056] From the perspective of enhancing the good apposition of the spring support 1 and the blood vessel 6, the site where the spring support 1 is implanted in the blood vessel 6 needs to maintain a relatively regular inner lumen space of the blood vessel 6. By connecting the cutting assembly 4 to the distal end of the push assembly 3, the lesion site of the blood vessel 6 can be cut before the spring support 1 is implanted, so that the inner wall of the blood vessel 6 remains relatively regular and smooth during implantation, thereby maintaining the effective adhesion of the outer wall of the spring support 1 to the inner wall of the blood vessel 6 and enhancing the matching performance of the blood vessel 6 and the spring support 1.

[0057] Specifically, the pushing assembly 3 is pushed and pulled by a push-pull tube 21 arranged inside the catheter 2, the push-pull tube 21 can be telescoped forward and backward relative to the catheter 2, thereby completing the pushing of the spring stent 1 out of the catheter 2 and the withdrawal of the pushing assembly 3 after the spring stent 1 is implanted.

[0058] The pushing assembly 3 includes two limiting discs connected to the push-pull tube 21, both of which are fixedly connected to the outer wall of the push-pull tube 21, and the distance between the two limiting discs is greater than the length of the spring stent 1. The spring stent 1 is in a compressed state during the pushing and implanting process due to the constraint of the catheter 2, and the spring stent 1 in the compressed state is arranged in the catheter 2, the side wall thereof in the radial direction keeps a close relationship with the inner wall of the catheter 2, and is located between the two limiting discs.

[0059] During normal delivery of the spring stent 1, the pushing assembly 3 and the cutting assembly 4 are arranged inside the distal opening of the catheter 2, and the push-pull tube 21 does not move relative to the catheter 2, that is, the pushing assembly 3 does not change the position of the spring stent 1 and the cutting assembly 4 in the catheter 2.

[0060] The catheter 2 reaches the lesion site of the blood vessel 6 under the guidance of the guide wire 7, and the catheter 2, the spring stent 1, the pushing assembly 3 and the cutting assembly 4 reach the lesion site of the blood vessel 6, before the catheter 2 reaches the lesion site of the blood vessel 6, the cutting assembly 4 is connected to the distal end of the pushing assembly 3 and arranged in the distal opening of the catheter 2.

[0061] Before the distal opening of the catheter 2 reaches the lesion site of the blood vessel 6, and before the spring stent 1 is implanted into the blood vessel 6, the lesion site of the blood vessel 6 needs to be cut first, specifically by the cutting assembly 4.

[0062] In another specific embodiment, a movable rod 22 is threaded inside the push-pull tube 21, and the movable rod 22 can be telescoped forward and backward relative to the distal opening of the push-pull tube 21, and the limiting discs include a proximal limiting disc 31 and a distal limiting disc 32 connected to the push-pull tube 21 respectively, during the delivery of the stent, the spring stent 1 is tightly attached to the inner wall of the catheter 2 due to the constraint of the catheter 2, and the proximal limiting disc 31 and the distal limiting disc 32 mainly limit the spring stent 1 in the catheter 2 to prevent the spring stent 1 from separating from the catheter 2.

[0063] Meanwhile, the limiting discs can be telescoped forward and backward relative to the axial direction of the catheter 2 under the pushing and pulling of the push-pull tube 21, so as to push and implant the spring stent 1 and withdraw the spring stent 1 after implantation.

[0064] In order to prevent blood from flowing back in the catheter 2 in the gap between the push-pull tube 21 and the movable rod 22, a sealing ring 26 is arranged between the movable rod 22 and the push-pull tube 21, which is a flexible rubber ring made of silicone rubber, and can avoid affecting the pushing and pulling of the movable rod 22 in the push-pull tube 21 while meeting the sealing requirements.

[0065] The cutting assembly 4 includes a blade 41 connected between the distal end of the movable rod 22 and the distal end side of the distal end limiting disc 32. During the delivery process of the spring support 1, the catheter 2, the push-pull tube 21 and the movable rod 22 are synchronously extended to the distal end of the blood vessel 6, and are kept in a relatively static relationship in the axial direction. The distal end opening of the movable rod 22 protrudes from the distal end opening of the push-pull tube 21, so that the blade 41 connected between the distal end of the movable rod 22 and the distal end limiting disc 32 is kept in an inclined state, forming a conical cutter arranged in the catheter 2, which can cut the lesion tissue entering the catheter 2 during the delivery process, and enhance the smoothness of the pushing process.

[0066] Referring to Figure 4 When it is necessary to cut the lesion part of the blood vessel 6, before reaching the lesion part, the extension of the catheter 2 to the distal end is stopped, the push-pull tube 21 is pushed to the distal end to extend the cutting assembly 4 from the catheter 2, and at the same time, the spring support 1 is moved forward under the pushing of the proximal end limiting disc 31. When the distal end limiting disc 32 reaches the distal end opening part of the catheter 2, the blade 41 of the cutting assembly 4 is completed to extend out of the catheter 2, the pushing of the push-pull tube 21 is stopped and the movable rod 22 is pulled back.

[0067] Preferably, the pulling back of the movable rod 22 makes the distal end of the movable rod 22 flush with the distal end opening of the push-pull tube 21, and the blade 41 connected between the distal end of the movable rod 22 and the distal end limiting disc 32 is bent and deformed to form a petal-shaped cutting knife, which cuts the lesion part in the blood vessel 6 by changing the shape of the cutting blade 41. Preferably, the outer diameter of the petal-shaped cutting knife is greater than the outer diameter of the catheter 2 and smaller than the inner diameter of the blood vessel 6, which can completely cut the lesion part on the inner wall of the blood vessel 6, and facilitate the full abutment of the spring support 1 and the inner wall of the blood vessel 6.

[0068] When the movable rod 22 is pulled back to the position and the blade 41 is bent and deformed, the petal-shaped cutting knife is moved to the distal end outside the catheter 2 to cut the lesion part, and at the same time, the spring support 1 is implanted from the catheter 2 into the blood vessel 6 by pushing the push-pull tube 21 and the movable rod 22 to the distal end at the same time.

[0069] In combination Figure 5 and referring to Figure 6, the spring stent 1 is in a relatively restrained compressed state and moves to the distal end of the catheter 2 under the pushing action of the proximal end limiting disc 31 during the implantation of the spring stent 1 into the blood vessel 6 by the catheter 2. When the proximal end limiting disc 31 extends out of the distal end opening of the catheter 2, the spring stent 1 is completely inserted into the blood vessel 6, and at the same time, the spring stent 1 is in close contact with the inner wall of the blood vessel 6 after cutting the lesion site, and the spring stent 1 changes from the relatively compressed state in the catheter 2 to the relatively stretched state in the blood vessel 6, and the implantation of the spring stent 1 at the lesion site is completed.

[0070] Based on the fact that the outer diameter of the petal-shaped cutting knife has been described above is greater than the outer diameter of the catheter 2, in order to enable the cutting assembly 4 to follow the push assembly 3 to retract into the catheter 2, after the implantation of the spring stent 1 is completed, the blade 41 of the cutting assembly 4 is restored to the initial conical cutter state by fixing the push-pull tube 21 and extending the movable rod 22 to the distal end, so that the peripheral size of the cutting assembly 4 is smaller than the inner diameter of the catheter 2, and the cutting assembly 4 and the push assembly 3 can be retracted into the catheter 2 through the synchronous pulling of the push-pull tube 21 and the movable rod 22, and then removed from the body through the catheter 2.

[0071] The movable rod 22 in the embodiment includes a solid structure of a nickel-titanium alloy rod, preferably a cylindrical rod, which can ensure the structural strength of the movable rod 22 and enhance the reliability of the deformation of the blade 41 during the pushing and pulling process of the movable rod 22.

[0072] The blade 41 in the embodiment includes a plurality of prismatic blades 41, specifically triangular prismatic blades 41, which are evenly distributed on the circumference of the distal end limiting disc 32 and are fixed between the distal end limiting disc and the movable rod by means of glue bonding or inlaying. One end of each triangular prismatic blade 41 is connected to the outer edge of the distal end of the distal end limiting disc 32, and the other end is concentrated and crossed at the distal end of the movable rod 22, which can facilitate the deformation of the blade 41.

[0073] The movable rod 22 is movably inserted into the push-pull tube 21 and can be extended and retracted relative to the distal end opening of the push-pull tube 21. By this arrangement, on the one hand, the cutting assembly 4 and the push assembly 3 can be effectively pushed, and on the other hand, the blade 41 can be reliably converted between the delivery state and the cutting state.

[0074] A limiting block 5 is arranged on the outer wall of the movable rod 22, and the limiting block 5 includes two fins located at the proximal end of the movable rod 22, which can be matched with the proximal end opening of the push-pull tube 21 and clamped on the proximal end opening of the push-pull tube 21. Through this arrangement, the cutting state of the petal-shaped cutting knife can be maintained when the two fins are clamped on the proximal end opening of the push-pull tube 21 after the movable rod 22 is pulled back. When the cutting is completed and the initial state of the cutting assembly 4 needs to be restored, the clamping relationship between the fins and the proximal end opening of the push-pull tube 21 is released.

[0075] The material of the blade 41 is nickel-titanium alloy material, which has good memory elasticity. When the clamping relationship between the fins and the proximal end opening of the push-pull tube is released during the transition of the cutting assembly 4 from the cutting state to the conical knife state, the distal cutting blade 41 will automatically stretch out distally based on the memory elasticity, driving the distal end of the movable rod 22 to stretch out forward and restore to the original conical knife state, effectively ensuring the reliability of the switching between different states.

[0076] The nickel-titanium alloy spring support 1 can be displayed in an external imaging device. In order to obtain the positional relationship between the movable rod 22 and the spring support 1 through the imaging device, an imaging ring 23 is arranged on the movable rod 22, which is preferably arranged at the position of the movable rod 22 relative to the extension and retraction of the push-pull tube 21, and is preferably made of platinum-iridium alloy material. The state of the blade 41 can be obtained by tracking the position of the movable rod 22.

[0077] Referring to Figure 7 In the embodiment, the push-pull tube 21 includes a main cavity 24 for the movable rod 22 to move through and a guide wire cavity 25 for the guide wire 7 to pass through. The main cavity 24 extends through the entire push-pull tube 21, i.e. in the overall length direction of the push-pull tube 21. Both ends of the main cavity 24 are open structures, ensuring the overall penetration of the movable rod 22 in the push-pull tube 21.

[0078] The guide wire cavity 25 is mainly used for guiding the guide wire 7, so that the tail end of the guide wire 7 enters from the distal end opening of the guide wire cavity 25 and exits from the proximal end opening of the guide wire cavity 25. By arranging the independent guide wire cavity 25 and the main cavity 24, the mutual influence of the push-pull assembly and the guide wire 7 in function can be avoided, and the stent graft system can be accurately delivered to the lesion site of the blood vessel 6 under the guidance of the guide wire 7.

[0079] Specifically, the distal end opening of the guide wire cavity 25 is arranged at the distal end of the push-pull tube 21, so that the movable rod 22 and the guide wire 7 can respectively extend out of the distal end opening of the push-pull tube 21, further reducing the mutual interference between them.

[0080] Through the stent catheter system in the application, the lesion part of the blood vessel 6 can be effectively cut, and the cutting of the lesion part is organically connected with the implantation of the spring stent 1 at the lesion cutting part, which greatly improves the implantation state of the spring stent 1, enables the outer wall of the spring stent 1 to be effectively attached to the inner wall of the blood vessel 6, and in combination with the memory elastic deformation of the spring stent 1, enables the spring stent 1 to follow the diastole and systole of the blood vessel 6 and deform freely, greatly avoids the risk of new thrombosis and neointimal hyperplasia under the premise of ensuring the stability of the stent implantation.

[0081] The application also provides a stent implantation method for the spring stent 1 according to the above stent catheter system, which comprises the following steps:

[0082] The proximal end of the guide wire 7 is inserted into the movable rod 22, and under the guidance of the guide wire 7, the catheter 2, the stent delivery device and the spring stent 1 compressed in the catheter 2 are sent to the lesion part along the guide wire 7;

[0083] Before the distal end of the catheter 2 reaches the lesion part, the extension of the catheter 2 is stopped, the deformation of the cutting assembly 4 at the distal end of the pushing assembly 3 is caused through the cooperation between the movable rod 22 and the push-pull tube 21, and the lesion part in the blood vessel 6 is cut after the deformation of the cutting assembly 4;

[0084] While cutting the lesion part, the spring stent 1 in the compressed state is pushed out of the catheter 2 to make it radially expand and expand, and the radially expanded spring stent 1 is attached to the inner wall of the blood vessel 6 after cutting the lesion part;

[0085] The cooperation relationship between the spring stent 1 after expansion and the inner wall of the blood vessel 6 is maintained, and the spring stent 1 follows the blood vessel 6 and self-scales in combination with the memory elasticity;

[0086] The initial state of the cutting assembly 4 is restored, the catheter 2 and the stent delivery device are withdrawn, and the implantation of the stent is completed.

[0087] The implantation method of the spring stent 1 in the application combines the cutting of the lesion part of the blood vessel 6 and the implantation of the spring stent 1, and makes them connect and fit, which can ensure the adhesion effect and implantation stability of the spring stent 1 and the blood vessel 6 to the greatest extent, and avoids the subjective factors of the doctor in selecting the stent specification by experience.

[0088] It should be pointed out that the diameter range of the spring stent in the application in the expanded state is actually selected according to the size of the inner diameter of the lesion part of the blood vessel, the wall thickness of the spring stent is 0.05-1mm, and the alloy sheet completed by hollowing in the manufacturing process is put into a shaping mold and is heat set under the heating condition of 100-800 DEG C in a drying oven.

[0089] It should be noted that the features of the embodiments in the present application can be combined with each other in the case of no conflict.

[0090] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. The present application can have various modifications and changes for those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A stent catheter system, characterized in that: The invention comprises a spring stent and a stent delivery device, wherein the stent catheter system is used for delivering and implanting the spring stent; The stent delivery device includes a catheter and a pushing assembly that can be extended and retracted relative to the catheter. The pushing assembly is used to push the spring stent out of the catheter and implant it into the blood vessel. The distal end of the pushing assembly is connected to a cutting assembly for cutting the diseased area in the blood vessel before implanting the spring stent. The spring support includes a spring, and the spring includes a cylindrical structure; A push-pull tube is provided inside the catheter, and the push-pull tube can be extended and retracted relative to the catheter. The pushing assembly includes two limit plates connected to the push-pull tube, and the spring bracket in a compressed state is provided in the catheter and located between the limit plates. A movable rod is connected to the push-pull tube, the limit plate includes a proximal limit plate and a distal limit plate, and the cutting assembly includes a blade connected between the movable rod and the distal limit plate; The blade comprises a plurality of prismatic blades, one end of each prismatic blade is connected to the outer edge of the distal limit plate, and the other end thereof is centrally crossed at the distal end of the movable rod; The process of delivering and implanting the spring stent by the stent catheter system includes the following steps: Delivering the catheter, the stent delivery device, and the spring stent compressed in the catheter to the lesion site along the guide wire; Cutting the lesion site by pushing the cutting component at the distal end of the component; Pushing the compressed spring support out of the catheter to make it stretch and expand radially; The spring stent expands to fit the inner wall of the blood vessel and scales itself up and down as the blood vessel contracts and relaxes; The catheter and stent delivery device are withdrawn to complete the stent implantation.

2. The stent catheter system according to claim 1, wherein: The cylindrical structure comprises a hollow cylinder with a memory alloy wire mesh spirally wound around it. The memory alloy wire mesh is kept flush at both ends of the hollow cylinder. The side wall of the clockwork spring is a hollow structure.

3. The stent catheter system according to claim 2, characterized in that: The memory alloy includes nickel-titanium alloy, and the clockwork spring is made of a rectangular nickel-titanium alloy wire mesh and can be expanded and contracted along the radial direction of the hollow cylinder.

4. The stent catheter system according to claim 3, characterized in that: The clockwork spring includes a contracted state and an extended state. The diameter of the hollow tube in the contracted state is 0.4-5 mm, and the diameter of the hollow tube in the extended state is 0.8-10 mm.

5. The stent catheter system according to claim 1, wherein: The material of the blade includes nickel-titanium alloy.

6. The stent catheter system according to claim 5, characterized in that: The plurality of prismatic blades are evenly distributed in the circumferential direction of the distal limiting disk.

7. The stent catheter system according to claim 5, characterized in that: A sealing ring is provided between the movable rod and the push-pull tube, and the movable rod comprises a nickel-titanium alloy rod with a solid structure.

8. The stent catheter system according to claim 7, characterized in that: A limit stopper is provided on the outer wall of the movable rod, and the limit stopper can be engaged with the proximal end of the push-pull tube. A developing ring is provided on the portion of the movable rod that is telescopic relative to the push-pull tube. The push-pull tube includes a main body cavity for the movable rod to movably penetrate and a guide wire cavity for the guide wire to penetrate. The main body cavity runs through the entire push-pull tube, and the distal opening of the guide wire cavity is arranged at the distal end of the push-pull tube.

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