A sheath assembly for endovascular intervention and an endovascular intervention device

Abstract

This invention provides a sheath assembly and device for endovascular interventional therapy. The sheath assembly includes a dilator, a sheath, and multiple drug-releasing components. The dilator has an expandable portion that can expand or contract radially. The sheath is fitted onto the dilator and has an openable portion with closed and open states. The openable portion includes multiple circumferentially arranged flaps. When closed, the flaps form a tubular structure; when open, they form a radial structure. Multiple drug-releasing components can be separately embedded between adjacent flaps. The sheath assembly is configured such that when the expandable portion changes from a radially contracted state to a radially expanded state, the openable portion changes from a closed state to an open state, and the drug-releasing components gradually detach from the flaps and move away from the axis of the sheath. This invention can reduce drug loss during delivery and improve the accuracy and safety of treatment.

Description

Technical Field

[0001] This invention belongs to the field of medical device technology, specifically relating to a sheath assembly and an endovascular interventional therapy device for endovascular interventional therapy. Background Technology

[0002] Sheath assemblies used in endovascular interventional therapy are a general term for medical devices that enter the body through a vascular access to perform minimally invasive treatments on blood vessels. The core function of these devices is to replace traditional surgery. By establishing a pathway through percutaneous puncture, the therapeutic device is delivered to the lesion site, enabling precise treatment of vascular stenosis, occlusion, and other lesions. They have advantages such as minimal trauma, rapid recovery, and fewer complications.

[0003] Currently, the sheath components widely used in clinical practice for endovascular interventional therapy mainly include balloon catheters (such as ordinary balloons, drug-coated balloons, and cutting balloons) and stent systems (such as bare metal stents, drug-eluting stents, and biodegradable stents). Their core function is to inhibit intimal hyperplasia and restenosis by mechanically dilating narrowed blood vessels and releasing drugs locally.

[0004] However, existing sheath assemblies for endovascular interventional therapy still have significant limitations in terms of drug delivery efficiency and device reliability. During delivery and expansion, the drug-coated balloon's surface load is susceptible to blood flow erosion and vessel wall friction, causing a large amount of drug to prematurely detach before reaching the target lesion site. Studies show that the amount of drug ultimately retained at the lesion site is often only 1% to 10% of the total coating, significantly reducing the local effective drug concentration and affecting treatment efficacy, and also posing potential safety risks due to systemic exposure. In terms of mechanical performance, the expansion of ordinary balloons can easily cause uneven stress on the vessel wall, leading to unexpected tears in the intima or plaque. If blood enters the subintimal layer through the tear, it can cause separation of the intima and media, forming an arterial dissection (false lumen), often requiring subsequent stent implantation for rescue. Furthermore, the stent system is subjected to pulsatile stress in the vessel for a long period after implantation, which may lead to adverse events such as stent fracture, displacement, and restenosis.

[0005] In summary, existing sheath assemblies for endovascular interventional therapy suffer from two major drawbacks: low drug delivery efficiency and insufficient device reliability, both of which necessitate improvements in efficacy and safety. Therefore, there is an urgent need in this field to develop a novel sheath assembly for endovascular interventional therapy that can significantly reduce drug loss during delivery and improve the precision and safety of treatment, thereby achieving efficient and reliable targeted therapy. Summary of the Invention

[0006] The purpose of this invention is to provide a novel sheath assembly and endovascular interventional device for endovascular interventional therapy, which can reduce drug loss during delivery and improve the accuracy and safety of treatment.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0008] The first aspect of the present invention provides a sheath assembly for endovascular interventional therapy, comprising:

[0009] A dilator includes a catheter body and an expandable portion disposed at the distal end of the catheter body, the expandable portion having a radially expanded state and a radially contracted state.

[0010] A sheath, fitted onto the expander, the sheath comprising a sheath body and an openable portion disposed at the distal end of the sheath body, the openable portion comprising a plurality of lobes arranged circumferentially along the sheath body, the openable portion having a closed state and an open state; when in the closed state, the plurality of lobes approach each other to form a tubular structure; when in the open state, the plurality of lobes move away from each other to form a radial structure; and...

[0011] Multiple drug-releasing components are separately embedded between two adjacent flaps along the circumferential and axial directions of the sheath, and each drug-releasing component includes a biodegradable body and a drug coating. The biodegradable body includes a base and a puncture portion.

[0012] The sheath assembly for endovascular interventional therapy is configured such that when the expandable portion transitions from the radially contracted state to the radially expanded state, the openable portion transitions from the closed state to the open state, and the drug-releasing assembly gradually detaches from the valve and moves away from the axis of the sheath.

[0013] This invention places the drug onto multiple drug-release components, which are then detachably mounted on the openable portion of a sheath. The drug-release components are delivered to the lesion site through the sheath with its openable portion closed. During this process, the amount of drug lost from the drug-release components is significantly reduced due to the protection of the sheath, and the safety of the delivery process is significantly improved. Upon reaching the lesion site, the distal end of the dilator expands, gradually opening the openable portion of the distal end of the sheath. The drug-release components are gradually exposed and separate from the sheath, simultaneously adhering to and penetrating the blood vessel wall as the distal end of the dilator expands. This achieves precise multi-site insertion into the blood vessel wall, effectively avoiding unexpected tearing of the vascular intima or plaque, and ensuring its safety after implantation.

[0014] In some embodiments, the base abuts against the outer surface of the expandable portion, which can improve the structural stability of the distal end of the sheath assembly, prevent radial displacement of the drug release assembly during delivery, and improve the efficiency of precise insertion of the drug release assembly during use.

[0015] In some embodiments, the flaps abut against the outer surface of the expandable portion, which can further restrict the drug release assembly and further improve the structural stability of the distal end of the sheath assembly.

[0016] In some embodiments, the drug-releasing component closest to the sheath body is spaced apart from the distal end of the sheath body to prevent the proximal end of the flap from being restricted by the drug-releasing component and thus affecting the opening of the opening portion.

[0017] In some embodiments, two adjacent lobes are bonded together. In this invention, the bonded connection is designed to break without the lobes breaking when subjected to a force exceeding 2N. More specifically, the bonded connection is formed by heat fusion at a temperature of 120°C to 200°C, and the fused sides separate without breaking or detaching when subjected to a force exceeding 2N.

[0018] In some embodiments, the opposite sides of the flaps are recessed to form grooves extending in the proximal direction. When two adjacent flaps come close together, the corresponding grooves enclose a receiving cavity for accommodating the drug sustained-release component.

[0019] Furthermore, multiple drug sustained-release components are sequentially and spaced apart in the receiving cavity along the proximal direction.

[0020] Specifically, the number of flaps can be set according to actual needs, the number of drug release components in the circumferential direction of the sheath can be selected, and the number of drug release components in the receiving cavity can be selected.

[0021] In this invention, the drug sustained-release component is configured such that when the drug sustained-release component is inserted into the blood vessel wall, the base is in contact with the inner wall of the blood vessel, and the puncture portion is located in the blood vessel wall.

[0022] In some embodiments, the projection of the base onto the proximal surface of the sheath body is arc-shaped, and the puncture portion includes a support arm extending radially outward from the middle of the base and a barb located at the end of the support arm.

[0023] In some specific embodiments, the petal is provided with a mating portion capable of engaging with the barb. In this invention, the engagement between the barb and the mating portion is designed such that when the force exceeds 2N, the engagement connection between the barb and the mating portion breaks, and neither the barb nor the mating portion breaks.

[0024] The drug sustained-release component is configured such that when the drug sustained-release component is inserted into the blood vessel wall, the base is in contact with the inner wall of the blood vessel, and the puncture part can penetrate the blood vessel wall beyond the intima and not beyond the media, or beyond the intima and media and not beyond the adventitia, or beyond the intima, media and adventitia.

[0025] Preferably, the drug-release component is configured such that when it is inserted into the vessel wall, the base abuts against the inner wall of the vessel, and the barb is located in the adventitia of the vessel wall. The puncture portion of the drug-release component penetrates the vessel wall beyond the media but not beyond the adventitia, and the base adheres to the inner wall of the vessel, compressing and fixing the intima and media of the vessel wall together to prevent delamination. Preoperatively, the thickness of the intima, media, and adventitia at the lesion site can be assessed by ultrasound. Based on the assessment results, a drug-release component of appropriate size is selected. For example, when the vessel wall is the femoral artery or coronary artery, preferably the shortest distance A from the barb to the base is greater than 0.3 mm and less than 0.7 mm, and the radial height B of the drug-release component in the sheath is greater than 0.7 mm and less than 0.9 mm.

[0026] In some other embodiments, the projection of the base onto the proximal surface of the sheath body is arc-shaped, and the puncture portion includes a puncture portion body whose projection onto the proximal surface of the sheath body is triangular and a gel layer disposed on the puncture portion body.

[0027] More specifically, the drug-release component is configured such that when it is inserted into the blood vessel wall, its base contacts the inner wall of the blood vessel, and the gel layer is located in the intima and media of the blood vessel wall. The gel layer can adhere the intima and media, eliminating dissection. Preoperatively, the thickness of the intima, media, and adventitia at the lesion site can be assessed by ultrasound. Based on the assessment results, a suitable size of drug-release component is selected. For example, when the blood vessel wall is a femoral artery or a coronary artery, the height C of the drug-release component in the radial direction of the sheath is preferably greater than 0.32 mm and less than 0.9 mm.

[0028] In some embodiments, the drug coating is formed from a mixture of a drug and a polymer, the polymer including one or more of PDLLA, PLGA, PLA, and PVDF-HFP, and the drug including one or more of paclitaxel, rapamycin, or derivatives of rapamycin.

[0029] In some embodiments, the biodegradable body is made of one or more of PLGA, PLA, magnesium-based alloys, octyl alloys, and iron-based alloys.

[0030] In some specific implementations, the drug-releasing component is designed to slowly release the drug over a period of one month to one year and to completely degrade over a period of one to one and a half years.

[0031] In some embodiments, the flap includes a first portion and a second portion extending in a proximal direction and arranged axially symmetrically to each other. When the openable portion is in the closed state, the first portion and the second portion abut against each other or are engaged. When the openable portion is in the open state, the first portion and the second portion are moved away from each other. This design can disperse the stress of the flap, making it easier to open. In this invention, the engagement between the first portion and the second portion is achieved by a snap-fit ​​mechanism designed to disconnect without breaking when subjected to a force exceeding 2N.

[0032] In some embodiments, the expander has a guidewire cavity extending in a direction parallel to its axis for the guidewire to pass through.

[0033] In this invention, various dilators conventionally used in the art can be selected. Preferably, a dilator that does not cause circumferential displacement of the drug-release component during radial expansion, or causes minimal displacement, is preferred. This ensures that the drug-release component moves radially away from the sheath's axis, penetrating the vessel wall as perpendicularly as possible. In some embodiments, the dilator is a balloon catheter.

[0034] In some embodiments, the sheath body and the openable portion are coaxial and integrally formed. Specifically, the sheath is made of a polymer material or a metal material, preferably a polymer material.

[0035] A second aspect of the present invention provides an endovascular interventional treatment device, which includes the sheath assembly described above and an operating handle disposed at the proximal end of the sheath assembly.

[0036] Furthermore, the operating handle includes a stress dispersion tube disposed at the proximal end of the sheath, a sheath seat disposed at the proximal end of the stress dispersion tube, a three-way valve connected to the sheath seat assembly, and an expander handle connected to the proximal end of the expander.

[0037] Furthermore, the endovascular interventional treatment device also includes a guidewire.

[0038] Due to the application of the above technical solution, the present invention has the following advantages compared with the prior art:

[0039] The sheath assembly for endovascular interventional therapy of the present invention detachably embeds multiple drug-release components into the openable portion of the sheath. During the delivery of the sheath to the lesion site, the drug-release components are protected by the sheath, effectively reducing drug loss. As the openable portion of the sheath opens with the radial expansion of the dilator, the drug-release components gradually separate from the sheath, becoming increasingly exposed and moving radially towards the vessel wall until their base adheres to the vessel wall, and the puncture site penetrates the vessel wall. This sheath assembly not only avoids drug loss and ensures safety during delivery but also allows multiple drug-release components to precisely penetrate the vessel wall at multiple sites, effectively preventing unintended tearing of the vascular intima or plaque and displacement of the drug-release components after implantation, thus ensuring therapeutic efficacy and the safety of the drug-release components after implantation. Attached Figure Description

[0040] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0041] Figure 1 This is a schematic diagram of an endovascular interventional therapy device;

[0042] Figure 2 This is a schematic diagram of the sheath assembly in the endovascular interventional treatment device of Example 1, with the dilator and a flap removed.

[0043] Figure 3 This is a schematic cross-sectional view of the distal end of the sheath assembly in the endovascular interventional therapy device of Example 1.

[0044] Figure 4 This is a three-dimensional structural diagram of the first drug sustained-release component;

[0045] Figure 5 This is a schematic cross-sectional view of the first drug sustained-release component;

[0046] Figure 6 This is a schematic cross-sectional view of the second type of drug sustained-release component;

[0047] Figure 7 This is a schematic diagram of the cross-sectional structure of the third type of drug sustained-release component;

[0048] Figure 8 This is a schematic diagram showing the state of the first drug-release component after it has been inserted into the blood vessel wall.

[0049] Figure 9This is a schematic diagram showing the state of the second drug-release component after it has been inserted into the blood vessel wall.

[0050] Figure 10 This is a schematic diagram showing the state of the third type of drug sustained-release component after it has been inserted into the blood vessel wall.

[0051] Figure 11 This is a schematic cross-sectional view of the distal end of the sheath assembly in its initial state.

[0052] Figure 12 This is a schematic cross-sectional view of the distal end of the sheath assembly during the expansion process.

[0053] Figure 13 This is a schematic cross-sectional view of the distal end of the sheath assembly in both the expanded and retracted states.

[0054] Figure 14 This is a schematic diagram of the sheath assembly in the endovascular interventional treatment device of Example 2, with the dilator and a flap removed.

[0055] Figure 15 This is a schematic cross-sectional view of the distal end of the sheath assembly in the endovascular interventional therapy device of Example 2.

[0056] Figure 16 This is a schematic diagram of the structure of the first part of a valve in the sheath assembly of the endovascular interventional therapy device in Example 2.

[0057] In the above attached figures,

[0058] 1. Sheath assembly; 11. Dilator; 111. Balloon; 12. Sheath; 121. Sheath body; 122. Openable part; 1221. Flange; 12211. First part; 12212. Second part; 12213. Snap; 1222. Groove; 1223. Fitting part; 13. Drug release assembly; 1311. Base; 1312. Puncture point; 13121. Support arm; 13122. Barb; 13123. Puncture point body; 13124. Gel layer; 2. Operating handle; 21. Stress dispersion tube; 22. Sheath seat; 23. Three-way valve; 24. Dilator handle; 3. Guidewire; 41. Inner membrane; 42. Middle membrane; 43. Outer membrane. Detailed Implementation

[0059] In the following description, only certain exemplary embodiments are briefly described. As those skilled in the art will recognize, the described embodiments can be modified in various ways without departing from the spirit or scope of the embodiments of the invention. Therefore, the drawings and description are considered to be exemplary in nature and not restrictive.

[0060] In the description of this invention, it should be understood that the terms "far" and "near," etc., indicate the orientation or positional relationship as defined by the orientation of the endovascular interventional therapy device during use, wherein the side closer to the operator is the proximal end, and the side farther from the operator is the distal end. "Axial" refers to the direction parallel to the line connecting the center of the distal and proximal ends of the instrument or component, and "radial" refers to the direction perpendicular to the axial direction; "inner" and "outer" are positions defined by distance relative to the center of the instrument or component, wherein "inner" is the position closer to the center of the instrument or component, and "outer" is the position farther from the center of the instrument or component. These terms are used only for the convenience of describing embodiments of the invention and for simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the embodiments of the invention.

[0061] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "fixed," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this invention according to the specific circumstances.

[0062] In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0063] The following disclosure provides many different implementations or examples for carrying out different structures of the embodiments of the present invention. To simplify the disclosure of the embodiments of the present invention, specific examples of components and arrangements are described below. Of course, these are merely examples and are not intended to limit the embodiments of the present invention. Furthermore, reference numerals and / or reference letters may be repeated in different examples of the embodiments of the present invention; such repetition is for simplification and clarity and does not in itself indicate a relationship between the various implementations and / or arrangements discussed.

[0064] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0065] Example 1:

[0066] This embodiment provides an endovascular interventional therapy device, such as... Figure 1 As shown, it includes a sheath assembly 1 and an operating handle 2 disposed at the proximal end of the sheath assembly 1.

[0067] Specifically, such as Figures 1 to 3 As shown, the sheath assembly 1 for endovascular interventional therapy includes a dilator 11, a sheath 12, and multiple drug release components 13.

[0068] The dilator 11 includes a catheter body and an expandable portion disposed at the distal end of the catheter body. The expandable portion has a radially expanded state and a radially contracted state. In this embodiment, the dilator 11 is a balloon catheter, which has a guidewire channel extending parallel to its axis for the guidewire 3 to pass through. In this embodiment, the inner diameter of the balloon 111 at the distal end of the balloon catheter gradually increases from the proximal end to the distal end, then remains constant, and then gradually decreases. This balloon catheter is a conventionally used balloon catheter for local radial dilation in the art, and will not be described in detail here.

[0069] The sheath 12 is fitted onto the expander 11. The sheath 12 includes a sheath body 121 and an openable portion 122 disposed at the distal end of the sheath body 121. The openable portion 122 includes a plurality of flaps 1221 arranged circumferentially along the sheath body 121. The openable portion 122 has a closed state and an open state. When it is in the closed state, the plurality of flaps 1221 approach each other to form a tubular structure. When it is in the open state, the plurality of flaps 1221 move away from each other to form a radial structure. In this embodiment, the flaps 1221 abut against the outer surface of the expandable portion. The opposite two sides of the flaps 1221 are recessed to form grooves 1222 extending in the proximal direction. When two adjacent flaps 1221 approach each other, the corresponding grooves 1222 surround each other to form a receiving cavity for accommodating the drug sustained-release component 13. In this embodiment, the sheath body 121 and the openable portion 122 are coaxial and integrally formed. Specifically, the sheath 12 is made of a polymer material. In this embodiment, two adjacent lobes 1221 are bonded together by hot-melt bonding at a temperature of 120°C to 200°C. When the force exceeds 2N, the hot-melt side tears without breaking or falling off.

[0070] Multiple drug-release components 13 are separately embedded between two adjacent flaps 1221 along the circumferential and axial directions of the sheath 12. Each drug-release component 13 includes a biodegradable body and a drug coating. The biodegradable body includes a base 1311 and a puncture portion 1312, wherein the base 1311 abuts against the outer surface of the expandable portion. Along the circumferential direction of the sheath 12, one drug-release component 13 is provided in each of two adjacent flaps 1221. Along the proximal-distal direction, multiple drug-release components 13 are sequentially spaced within the receiving cavity, and the drug-release component 13 closest to the sheath body 121 is at a distance from the distal end of the sheath body 121 to prevent the proximal end of the flap 1221 from being restricted by the drug-release component and affecting the opening of the opening portion. In this embodiment, the drug-release component 13 is configured such that when the drug-release component 13 punctures the blood vessel wall, the base 1311 abuts against the inner wall of the blood vessel, and the puncture portion 1312 is located within the blood vessel wall.

[0071] In this embodiment, the sheath assembly 1 for endovascular interventional therapy is configured such that when the expandable portion changes from a radially contracted state to a radially expanded state, the openable portion 122 changes from a closed state to an open state, and the drug release assembly 13 gradually detaches from the valve 1221 and moves away from the axis of the sheath 12.

[0072] Specifically, the drug sustained-release component 13 can be designed in various structures, such as Figure 4 and Figure 5 or Figure 6 As shown, the projection of the base 1311 onto the proximal surface of the sheath body 121 is arc-shaped. The puncture portion 1312 includes a support arm 13121 extending radially outward from the middle of the base 1311 and a barb 13122 located at the end of the support arm 13121. Correspondingly, the flap 1221 is provided with a mating portion 1223 capable of engaging with the barb 13122. In this invention, the engagement between the barb 13122 and the mating portion 1223 is designed such that when the force exceeds 2N, the engagement connection between the barb 13122 and the mating portion 1223 breaks, and neither the barb 13122 nor the mating portion 1223 breaks. In this embodiment, the barb 13122 is provided with a drug coating. Figure 8 or Figure 9 As shown, when the drug-releasing component 13 pierces the blood vessel wall, the base 1311 abuts against the inner wall of the blood vessel, and the barb 13122 is located in the adventitia 43 of the blood vessel wall. The puncture portion 1312 of the drug-releasing component 13 pierces the blood vessel wall beyond the media 42 but not beyond the adventitia 43, and the base 1311 adheres to the inner wall of the blood vessel, squeezing and fixing the intima 41 and media 42 of the blood vessel wall together to prevent the intima 41 and media 42 from forming a dissection. Taking the superficial femoral artery as an example, the shortest distance A from the barb 13122 to the base 1311 is greater than 0.3 mm and less than 0.7 mm, and in this embodiment it is 0.5 mm; the height B of the drug-releasing component 13 in the radial direction of the sheath 12 is greater than 0.7 mm and less than 0.9 mm, and in this embodiment it is 0.8 mm. For example... Figure 7 As shown, the projection of the base 1311 onto the proximal surface of the sheath body 121 is arc-shaped, and the puncture portion 1312 includes a puncture portion body 13123 whose projection onto the proximal surface of the sheath body 121 is triangular, and a gel layer 13124 disposed outside the puncture portion body 13123. Figure 10 As shown, when the drug-releasing component 13 is inserted into the blood vessel wall, the gel layer 13124 is located in the intima 41 and media 42 of the blood vessel wall. The gel layer 13124 can bond the intima 41 and media 42 together, eliminating dissection. Taking the superficial femoral artery as an example, the height C of the drug-releasing component 13 in the radial direction of the sheath 12 is greater than 0.32 mm and less than 0.7 mm, and in this embodiment it is 0.5 mm.

[0073] Specifically, the drug coating is formed from a mixture of a drug and a polymer, including one or more of PDLLA, PLGA, PLA, and PVDF-HFP. In this embodiment, the drug is selected as rapamycin or a rapamycin derivative. An undercoat may also be selectively designed under the drug coating, preferably a polybutyl methacrylate (PBuMA) coating, and the drug concentration is preferably 0.05 μg / mm. 2 -3.0 μg / mm 2 The preferred drug release profile is 60% release within 7 days, 80% release within 30 days, 95% release within 90 days, and complete release within 1 year. The biodegradable body is made of one or more of PLGA, PLA, magnesium-based alloys, octyl alloys, and iron-based alloys. This drug sustained-release component 13 is designed to slowly release the drug within one month to one year and to completely degrade within one to one and a half years.

[0074] In this embodiment, the operating handle 2 includes a stress dispersion tube 21 disposed at the proximal end of the sheath 12, a sheath seat 22 disposed at the proximal end of the stress dispersion tube 21, a three-way valve 23 connected to the sheath seat 22 assembly, and an expander handle 24 connected to the proximal end of the expander 11. In this embodiment, the endovascular interventional treatment device also includes a guidewire 3.

[0075] Example 2:

[0076] This embodiment provides another endovascular interventional treatment device, which is basically the same as that in Embodiment 1, except that the structure of the flap 1221 is slightly different. In this embodiment, the flap 1221 includes a first part 12211 and a second part 12212 that extend along the proximal and distal directions and are axially symmetrically arranged. When the openable portion 122 is in the closed state, the first part 12211 and the second part 12212 abut against each other or are engaged with each other. When the openable portion 122 is in the open state, the first part 12211 and the second part 12212 are far apart. This design can disperse the stress on the flap 1221, making it easier to open. More specifically, as shown... Figures 14 to 16 As shown, the snap-fit ​​between the first part 12211 and the second part 12212 is achieved by a snap-fit ​​12213, which is designed to disconnect the connection without breaking when the force exceeds 2N.

[0077] The methods of using the endovascular interventional therapy devices of Embodiments 1 and 2 described above are as follows:

[0078] In its initial state, the expandable portion of the dilator 11 (i.e., the distal balloon 111) is in a radially contracted state, and the openable portion 122 at the distal end of the sheath body 121 is in a closed state. Multiple drug-releasing components 13 are located within the openable portion 122, which is fitted onto the outer surface of the expandable portion. During use, the endovascular interventional device in its initial state is guided by the guidewire 3 to deliver the distal end of the sheath components to the lesion site. The dilator is manipulated to change the expandable portion from a radially contracted state to a radially expanded state. The openable portion 122 at the distal end of the sheath 12 gradually opens, and the drug-releasing components 13 gradually emerge and separate from the sheath 12. Simultaneously, as the distal end of the dilator expands, the components adhere to and penetrate the vessel wall. The sheath 12 is then withdrawn, and the dilator is manipulated to restore the expandable portion to a radially contracted state, withdrawing it from the body along with the sheath 12, thus completing the implantation of the drug-releasing components 13.

[0079] The above embodiments are only for illustrating the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They should not be construed as limiting the scope of protection of the present invention. All equivalent changes or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A sheath assembly for use in an endovascular intervention, characterized by: It includes: Dilator (11), comprising a catheter body and an expandable portion disposed at the distal end of the catheter body, the expandable portion having a radially expanded state and a radially contracted state. A sheath (12), fitted onto the expander (11), the sheath (12) comprising a sheath body (121) and an openable portion (122) disposed at the distal end of the sheath body (121), the openable portion (122) comprising a plurality of lobes (1221) arranged circumferentially along the sheath body (121), the openable portion (122) having a closed state and an open state; when in the closed state, the plurality of lobes (1221) abut together to form a tubular structure; when in the open state, the plurality of lobes (1221) abut together to form a radial structure; and, Multiple drug-releasing components (13) are separately embedded between two adjacent flaps (1221) along the circumferential and axial directions of the sheath (12). Each drug-releasing component (13) includes a biodegradable body and a drug coating. The biodegradable body includes a base (1311) and a puncture portion (1312). The projection of the base (1311) onto the proximal surface of the sheath body (121) is arc-shaped. The puncture portion (1312) includes a support arm (1) extending radially outward from the middle of the base (1311). 3121) and a barb (13122) located at the end of the support arm (13121), the flap (1221) is provided with a mating part that can engage with the barb (13122); or, the projection of the base (1311) on the proximal surface of the sheath body (121) is arc-shaped, the puncture part (1312) includes a puncture part body (13123) whose projection on the proximal surface of the sheath body (121) is triangular and a gel layer (13124) disposed on the puncture part body (13123). The sheath assembly for endovascular interventional therapy is configured such that when the expandable portion transitions from the radially contracted state to the radially expanded state, the openable portion (122) transitions from the closed state to the open state, and the drug release assembly (13) gradually detaches from the valve (1221) and moves away from the axis of the sheath (12).

2. The sheath set for use in interventional treatment of blood vessels according to claim 1, characterized in that: The base (1311) abuts against the outer surface of the expandable portion; And / or, the flap (1221) abuts against the outer surface of the expandable portion; And / or, there is a distance between the drug release component (13) closest to the sheath body (121) and the distal end of the sheath body (121); And / or, two adjacent lobes (1221) are bonded together.

3. The sheath set for use in interventional treatment of blood vessels according to claim 1, characterized in that: The opposite sides of the flap (1221) are recessed to form grooves (1222) extending in the proximal direction. When two adjacent flaps (1221) come close to each other, the corresponding grooves (1222) surround each other to form a receiving cavity for accommodating the drug sustained-release component (13).

4. The sheath set for use in interventional treatment of blood vessels according to claim 3, characterized in that: Multiple drug release components (13) are arranged sequentially at intervals in the receiving cavity along the proximal direction.

5. The sheath set for use in interventional therapy of blood vessels according to claim 1, characterized in that: The drug-releasing assembly (13) is configured such that when the drug-releasing assembly (13) penetrates the blood vessel wall, the base (1311) abuts against the inner wall of the blood vessel, and the barbs are located in the outer membrane (43) of the blood vessel wall. Alternatively, the drug release assembly (13) is configured such that when the drug release assembly (13) is inserted into the blood vessel wall, the base (1311) abuts against the inner wall of the blood vessel, and the gel layer (13124) is located in the intima (41) and media (42) of the blood vessel wall.

6. The sheath assembly for endovascular interventional therapy according to claim 1, characterized in that: The drug coating is formed from a mixture of a drug and a polymer, wherein the polymer includes one or more of PDLLA, PLGA, PLA, and PVDF-HFP, and / or the drug includes one or more of paclitaxel, rapamycin, or rapamycin derivatives. And / or, the material of the biodegradable body includes one or more of PLGA, PLA, magnesium-based alloys, octyl alloys, and iron-based alloys.

7. The sheath assembly for endovascular interventional therapy according to claim 1, characterized in that: The petal (1221) includes a first part (12211) and a second part (12212) that extend along the proximal and distal directions and are symmetrically arranged with respect to each other. When the openable part (122) is in the closed state, the first part (12211) and the second part (12212) abut against each other or are locked together. When the openable part (122) is in the open state, the first part (12211) and the second part (12212) are far apart.

8. The sheath assembly for endovascular interventional therapy according to claim 1, characterized in that: The expander (11) has a guide wire cavity extending in a direction parallel to its axis for the guide wire to pass through. And / or, the dilator (11) is a balloon catheter; And / or, the sheath body (121) and the openable portion (122) are coaxial and integrally formed.

9. An endovascular interventional therapy device, characterized in that, It includes a sheath assembly according to any one of claims 1 to 8 and an operating handle (2) disposed at the proximal end of the sheath assembly (1).

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