Drug balloon catheter

Abstract

The present application relates to a kind of drug balloon catheter, including inner tube, outer tube, outer balloon, multiple inner balloon, multiple connecting mechanism, Shockwave generating mechanism and conductive lining core;Wherein, the balloon wall of outer balloon includes barrier layer, the drug storage layer of containing therapeutic drug and controlled-release outer layer;Shockwave generating mechanism includes multiple units, and each unit includes connecting core and Shockwave generating device;The drug balloon catheter is configured as: when the outer balloon in the inflation working condition is locally extruded, the inner balloon of corresponding position is pressed, drives its corresponding connecting core to the movement of conductive lining core and forms electrical contact, to trigger corresponding Shockwave generating device to generate Shockwave, Shockwave acts on the controlled-release outer layer of the region that outer balloon is locally extruded, makes the pore of this region open or increase, to release drug in target, accurately release drug in lesion site, realize efficient, safe target therapy, reduce the loss of drug in delivery process.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of medical devices, and particularly relates to a drug balloon catheter. BACKGROUND

[0002] Drug-coated Balloon (DCB) as an interventional device integrating mechanical expansion and local drug therapy plays an increasingly important role in the treatment of cardiovascular stenosis and calcification diseases. By releasing anti-proliferative drugs to the lesion site during balloon expansion, it effectively inhibits the excessive proliferation of the vascular intima, thereby reducing the risk of vascular restenosis.

[0003] However, the current DCB products on the market generally face the severe challenges of low drug transfer rate and huge drug loss during delivery. Most of the drugs loaded on the surface of the balloon are prematurely shed and washed away by the blood flow during the passage through the blood vessel and the expansion process, and the actual amount of drugs reaching and retaining at the target lesion site is extremely low. Studies have shown that the initial drug transfer rate of some products is less than 10%, and the drug loss rate during delivery can be as high as 80% or more. In order to compensate for such huge drug loss and ensure sufficient effective dose at the lesion site, existing technical solutions have to rely on initially loading a large dose of high-density drugs on the balloon. This "quantity-based" strategy not only greatly increases the production cost, but more importantly, it may bring potential long-term safety risks due to increased systemic drug exposure.

[0004] In addition, the current DCB drug coating is usually uniformly covered on the entire balloon surface, and when it is used to expand non-circumferential (i.e. non-uniform) stenosis or local calcification lesions, the drugs will be released indiscriminately in all areas where the balloon contacts the blood vessel wall. This results in a large amount of drugs acting on the normal vascular intima, not only exacerbating the problem of low drug utilization, but also possibly causing unnecessary drug exposure and damage to normal vascular tissue, affecting the early healing of the blood vessel, and even possibly causing adverse biological reactions.

[0005] In summary, the existing drug-coated balloon technology is limited in further improving its efficacy and safety due to the two major defects of high drug loss rate and lack of targeting. Therefore, there is an urgent need in the field to develop a new type of drug balloon catheter to significantly reduce drug loss during delivery and precisely release drugs to the lesion site, thereby achieving efficient and safe targeted therapy. SUMMARY

[0006] The purpose of the present application is to provide a new type of drug balloon catheter to reduce drug loss during delivery and precisely release drugs to the lesion site, thereby achieving efficient and safe targeted therapy.

[0007] To achieve the above object, the technical scheme adopted by the present application is:

[0008] The present application provides a drug balloon catheter, comprising an inner tube, an outer tube sleeved outside the inner tube, and an outer balloon arranged at the distal end of the outer tube and the inner tube, a fluid channel being formed between the inner tube and the outer tube and communicating with the outer balloon; the drug balloon catheter further comprises:

[0009] A plurality of inner balloons are uniformly arranged in the outer balloon in the circumferential direction;

[0010] A plurality of connection mechanisms are arranged one by one and independently, each connection mechanism having a liquid injection channel and a conductive channel, the liquid injection channel communicating the corresponding inner balloon with the fluid channel, and the conductive channel communicating the corresponding inner balloon with the inner cavity of the inner tube;

[0011] A plurality of units of a shock wave generating mechanism correspond to the inner balloons one by one, each unit comprising a connecting core arranged in the conductive channel and a shock wave generating device arranged on the connecting core, the connecting core being in sliding sealing cooperation with the conductive channel so that the inner balloon and the inner cavity of the inner tube are always in an isolated state; and

[0012] A conductive lining core is movably arranged in the inner tube;

[0013] The balloon wall of the outer balloon comprises, from the inside out, a barrier layer, a drug storage layer containing therapeutic drugs, and a controlled release outer layer, and the controlled release outer layer is distributed with a plurality of pores;

[0014] The drug balloon catheter is configured such that when the outer balloon in the inflated working state is locally extruded, the inner balloon at the corresponding position is pressed, the connecting core thereof is driven to move towards the conductive lining core and form an electrical contact, so as to trigger the shock wave generating device to generate a shock wave, the shock wave acting on the controlled release outer layer of the region of the outer balloon subjected to local extrusion, so as to open or increase the pores of the region, thereby releasing the drugs targetedly.

[0015] In some embodiments, when the inner balloon is in the inflated working state, the outer wall is in contact with the inner wall of the outer balloon, and the side wall thereof is in contact with the adjacent inner balloon.

[0016] In some embodiments, the controlled release outer layer is configured such that when not subjected to the shock wave, the pores are in a closed or extremely small state to hinder the release of drugs.

[0017] In some specific embodiments, when not subjected to the shock wave, the size of the pores of the controlled release outer layer is smaller than the particle size of the therapeutic drugs in the drug storage layer.

[0018] In some embodiments, the outer control layer is made of polytetrafluoroethylene (PTFE), expanded polytetrafluoroethylene (ePTFE), or nylon (PA).

[0019] In some embodiments, the shockwave generating device is a shockwave electrode.

[0020] In some embodiments, the sliding direction of the connecting core is consistent with the radial direction of the inner tube.

[0021] In some embodiments, the plurality of inner balloons are arranged in multiple groups along the axial direction of the catheter; each group comprises a plurality of inner balloons arranged uniformly in the circumferential direction, and the number of inner balloons in each group is the same or different.

[0022] In some embodiments, the connecting mechanism comprises a connecting seat and a liquid injection sleeve. The connecting seat comprises a first seat body arranged on the inner wall of the inner tube, a second seat body arranged in the corresponding inner balloon, and a pipe connecting the first seat body and the second seat body, the pipe having a through inner channel, which constitutes the conductive channel. The liquid injection sleeve is arranged on the outer side of the pipe, and the corresponding inner balloon is fixedly connected to the outer surface of the liquid injection sleeve. The gap between the liquid injection sleeve and the pipe constitutes the liquid injection channel, and the pipe wall of the liquid injection sleeve is provided with a plurality of through holes, part of which are located in the corresponding inner balloon, and the other part is located on the outer side of the corresponding inner balloon.

[0023] In some embodiments, the unit further comprises an elastic element arranged in the conductive channel, which is configured to apply an elastic force to the connecting core away from the conductive lining core, so that the connecting core remains in the initial position when not under pressure. The elastic element includes but is not limited to a spring.

[0024] In some embodiments, the connecting core comprises a main body and a blocking part arranged at one end of the main body, and the elastic element is sleeved on the main body and acts on the blocking part.

[0025] In some embodiments, the conductive lining core is a hollow structure, and its distal end is connected to a lining balloon, which is in communication with the hollow cavity of the conductive lining core.

[0026] In some embodiments, the conductive lining core and the inner tube have a gap for the circulation of cooling medium.

[0027] In some embodiments, the conductive lining core comprises a cylindrical lining core main body and one or more bosses arranged on the circumferential side of the lining core main body.

[0028] In some specific embodiments, the protrusions are fan-shaped, and specifically two of them are arranged on two sides of the core body, and the outer edge contours of the two protrusions and the outer edge contour of the core body jointly define the gap.

[0029] Thanks to the above technical solution, the present application has at least the following advantages compared with the prior art:

[0030] The present application can stably "lock" the drug on the outer balloon through the special multi-layer structure design of the outer balloon, prevent the drug from falling off and flowing away too early when the balloon passes through the tortuous blood vessel path and the initial expansion stage, thereby reducing the initial total amount of drug required by the balloon, avoiding the potential systemic toxicity risk caused by large-dose drug exposure, and improving the safety of treatment.

[0031] The present application also realizes targeted drug delivery through the design of the inner balloon, the connecting mechanism and the shock wave generating mechanism, and the targeted drug delivery process is automatically triggered by the stenosis morphology of the blood vessel itself without the need for complex additional operations by the operator. Specifically, when the balloon is placed at a non-circumferential stenosis site, only the inner balloon subjected to extrusion by the stenosis blood vessel wall will trigger its corresponding shock wave generating device, and the generated shock wave will mainly act on the controlled-release outer layer of the corresponding region of the outer balloon, which can act on the plaque at the stenosis site to expand the plaque at the stenosis site through instantaneous high pressure, and can also locally open or increase the drug release channels. This mechanism ensures that the drug release is highly matched with the lesion anatomy, and can precisely enrich the drug at the target position that needs it most, realizing an automatic closed loop of "contact-trigger-release", integrating physical morphology sensing and drug release control, ensuring the accuracy and consistency of treatment, and avoiding human judgment errors. At the same time, it also avoids unnecessary release of the drug in the normal blood vessel segment, thereby greatly reducing the damage to the normal blood vessel intima and promoting the healthy healing of the blood vessel. In addition, this mechanism does not require high balloon expansion pressure, and a lower pressure value further reduces the risk of damage to the normal blood vessel. BRIEF DESCRIPTION OF DRAWINGS

[0032] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0033] Figure 1 is a perspective view of the structure of the drug balloon catheter of Example 1;

[0034] Figure 2 is another perspective view of the structure of the drug balloon catheter of Example 1;

[0035] Figure 3 Structure exploded view of the drug balloon catheter of Example 1;

[0036] Figure 4 Structure schematic view of the connecting mechanism, connecting core and elastic element of Example 1;

[0037] Figure 5 Structure schematic view of the connecting mechanism, connecting core and elastic element and inner tube of Example 1;

[0038] Figure 6 Structure schematic view of the connecting mechanism, connecting core and elastic element of Example 1 when the inner balloon is not squeezed;

[0039] Figure 7 Structure schematic view of the connecting mechanism, connecting core and elastic element of Example 1 when the inner balloon is squeezed;

[0040] Figure 8 Structure schematic view of the conductive lining core of Example 1;

[0041] Figure 9 Structure perspective view of another drug balloon catheter of Example 1;

[0042] Wherein: 1, outer balloon; 2, inner tube; 3, outer tube; 4, inner balloon; 5, connecting mechanism; 51, connecting seat; 511, first seat body; 512, second seat body; 513, pipe fitting; 514, conductive channel; 52, liquid injection sleeve; 521, through hole; 6, connecting core; 61, main body part; 62, blocking part; 7, elastic element; 8, conductive lining core; 81, lining core main body; 82, first fan-shaped boss; 83, second fan-shaped boss; 84, lining core balloon; 85, hollow cavity; 9, end cap. DETAILED DESCRIPTION

[0043] In the following, only certain exemplary embodiments are simply described. As those skilled in the art can recognize, the described embodiments can be modified in various different ways without departing from the spirit or scope of the embodiments of the present application. Therefore, the drawings and the description are considered to be exemplary in nature rather than limiting.

[0044] In the description of the embodiments of the present application, it is to be understood that the terms "far", "near" and the like indicate the position or location relationship is defined with the position of the drug balloon catheter in use, wherein the side close to the operator is the proximal end, and the side away from the operator is the distal end. It is only for the convenience of describing the embodiments of the present application and simplifying the description, and does not indicate or imply that the indicated device or element must have a particular position, be constructed and operated in a particular position, and therefore cannot be understood as a limitation on the embodiments of the present application.

[0045] Furthermore, the terms "first", "second", and the like, do not denote any quantity or order, but rather serve as names, labels or identifiers in the description of the embodiments. It is also to be understood that the terminology and phraseology employed herein are for the purpose of description and illustration only and similar terms of endearment are to be construed in an appropriate context as being variable.

[0046] In the description of the embodiments of the application, the meaning of "a plurality" is two or more, unless otherwise explicitly specified and limited.

[0047] The following disclosure provides many different embodiments, or examples, for implementing different structures of the embodiments of the application. For the purpose of simplification, the elements of the particular examples in the following description are not described in complete detail. It is to be understood that the description is related to only one example, and is merely made by way of example. As such, the application is not limited to particular examples described. Furthermore, the application can incorporate different examples in different embodiments, and such repetitions are for the purpose of simplicity and clarity and do not in themselves indicate a relationship between the various embodiments and / or arrangements discussed.

[0048] The embodiments of the application will be described in detail below with reference to the drawings.

[0049] Embodiment 1: A drug balloon catheter, such as Figures 1 to 9As shown, it comprises an inner tube 2, an outer tube 3, an outer balloon 1, a plurality of inner balloons 4, a plurality of connection mechanisms 5, a shock wave generating mechanism and a conductive lining 8. The outer tube 3 is sleeved outside the inner tube 2, preferably coaxially arranged with the inner tube 2. The outer balloon 1 is fixedly arranged at the distal end of the inner tube 2 and the outer tube 3, and its balloon wall comprises, from the inside out, a barrier layer, a drug storage layer containing therapeutic drugs, and a controlled release outer layer, and the controlled release outer layer is distributed with a plurality of pores. A fluid channel in communication with the outer balloon 1 is formed between the inner tube 2 and the outer tube 3, for passing in or out of the inflation medium, so that the outer balloon 1 is inflated or contracted. A plurality of inner balloons 4 are uniformly arranged in the outer balloon 1 in the circumferential direction. The connection mechanism 5 has a plurality of connection mechanisms 5, and the plurality of connection mechanisms 5 are arranged one by one and independently with the inner balloon 4, and each connection mechanism 5 has a liquid injection channel and a conductive channel 514. The liquid injection channel communicates the corresponding inner balloon 4 with the fluid channel, and the conductive channel 514 communicates the corresponding inner balloon 4 with the inner cavity of the inner tube 2. The shock wave generating mechanism has a plurality of units corresponding to the inner balloon 4. Take one of the units as an example, it includes a connecting core 6 arranged in the corresponding conductive channel 514 and a shock wave generating device arranged on the connecting core 6. The connecting core 6 is in sliding sealing cooperation with the corresponding conductive channel 514, so that the inner balloon 4 and the inner cavity of the inner tube 2 are always in an isolated state, avoiding the inflow of the inflation medium in the inner balloon 4 into the inner cavity of the inner tube 2. The conductive lining 8 is movably arranged in the inner tube 2.

[0050] The drug balloon catheter is configured such that when the outer balloon 1 in the inflated working state is locally extruded, the inner balloon 4 at the corresponding position is pressed, driving its corresponding connecting core 6 to move towards the conductive lining 8 and form an electrical contact, to trigger the corresponding shock wave generating device to generate a shock wave, which acts on the controlled release outer layer of the locally extruded region of the outer balloon 1, so as to open or increase the pores of the region, thereby releasing the drug.

[0051] The drug balloon catheter can significantly reduce the loss of drugs during delivery, and can accurately release the drugs to the lesion site, thereby achieving efficient and safe targeted therapy. This is mainly reflected in:

[0052] During delivery, the inner balloon 4 and the outer balloon 1 are in a contracted state. The pores of the controlled release outer layer of the outer balloon 1 are in a closed or very small state to hinder the release of the drugs (such as anti-proliferative drugs, including but not limited to paclitaxel, rapamycin and its derivative drugs) in the drug storage layer, thereby reducing or avoiding the loss of drugs during delivery.

[0053] When the drug balloon catheter reaches the target lesion blood vessel site, the inflation medium (preferably a liquid inflation medium such as saline or contrast medium mixture) is injected into the outer balloon 1 through the fluid channel formed between the inner tube 2 and the outer tube 3, causing the outer balloon 1 to expand and adhere to the lesion site on the inner wall of the blood vessel. At the same time, the inflation medium enters the inner balloon 4 through the injection channel, causing the inner balloon 4 to expand. During this process, the drug in the drug reservoir is still not released or only a small amount of drug is released due to the restriction of the controlled-release outer layer.

[0054] When the inner balloon 4 and the outer balloon 1 are in the expanded working state and the outer balloon 1 is in contact with the lesion (such as an atherosclerotic plaque), it will be subjected to local extrusion from the lesion. The local extrusion pressure is transmitted to the inner balloon 4 inside the outer balloon 1. Since the multiple circumferentially uniformly distributed inner balloons 4 are independent of each other and are constrained by the outer balloon 1, and the liquid inflation medium is incompressible. Therefore, the specific inner balloon 4 corresponding to the extrusion area is compressed. When this inner balloon 4 is compressed, the internal pressure rises, which drives the connecting core 6 in the corresponding connecting mechanism 5 to move towards the catheter axis. When the driven connecting core 6 moves to the axis and contacts the conductive lining core 8, an electrical contact is formed between the two, forming a closed circuit. The electrical signal triggers the shock wave generating device on the connecting core 6, generating a shock wave in the corresponding inner balloon 4. The shock wave energy is accurately transmitted to the corresponding local area of the outer balloon 1 wall through the fluid in the inner balloon 4 and the outer balloon 1. The shock wave acts on the controlled-release outer layer of the area, which can act on the plaque at the stenosis site, causing the plaque at the stenosis site to expand through instantaneous high pressure; it can also "open", "enlarge" or "break" the pre-existing micropore on it, so that the drug in the drug reservoir can be quickly released from the specific position, avoiding unnecessary drug release in the relatively healthy blood vessel segment or non-lesion area, improving the safety of treatment, and also optimizing the drug utilization.

[0055] As a preferred embodiment, the controlled-release outer layer is covered with pores; and when not subjected to the shock wave, the size of the pores in the controlled-release outer layer is smaller than the particle size of the drug in the drug reservoir. The material of the controlled-release outer layer can be polytetrafluoroethylene (PTFE), expanded polytetrafluoroethylene (ePTFE), or nylon. The material of the barrier layer can refer to the existing balloon materials in the art. As an example, the material of the barrier layer can be any one of nylon, block polyether amide resin (Pebax), PTFE, polyethylene terephthalate (PET), polyimide (PI), thermoplastic polyurethane elastomer (TPU), thermoplastic elastomer (Tpe), fluorinated ethylene propylene copolymer (FEP), and silicone.

[0056] The number of the plurality of inner balloons 4 can be designed according to actual needs, and is preferably 3-8. In the embodiment, the number of the inner balloons 4 is 6. In other embodiments, the plurality of inner balloons 4 are arranged in groups along the axial direction of the catheter; each group contains a plurality of inner balloons 4 arranged uniformly in the circumferential direction to achieve targeted drug delivery in a longer area. Further, the number of inner balloons 4 in each group can be the same or different according to actual needs.

[0057] As shown in Figure 3 and Figure 4 , the connecting mechanism 5 includes a connecting seat 51 and a liquid injection sleeve 52. The connecting seat 51 includes a first seat body 511, a second seat body 512, and a pipe 513, which are preferably integrally formed. The first seat body 511 is fixedly arranged on the wall of the inner tube 2, and is preferably arc-shaped to match the inner wall of the inner tube 2; the second seat body 512 is arranged inside the corresponding inner balloon 4; the pipe 513 connects the first seat body 511 and the second seat body 512, and has a conductive channel 514 passing through the inside. The liquid injection sleeve 52 is arranged outside the pipe 513, and is preferably coaxially arranged with the pipe 513. An annular gap is formed between the liquid injection sleeve 52 and the outer wall of the pipe 513, constituting a liquid injection channel. The corresponding inner balloon 4 is fixedly connected to the outer surface of the liquid injection sleeve 52. A plurality of through holes 521 are distributed on the wall of the liquid injection sleeve 52, and a part of the through holes 521 are open inside the inner balloon 4, while the other part of the through holes 521 are open outside the inner balloon 4, so that the liquid injection channel can pass through the through holes 521 on the liquid injection sleeve 52, and simultaneously communicate with the inside of the inner balloon 4 and the inside of the outer balloon 1. Therefore, when the inflation medium is injected or pumped through the fluid channel, the medium can pass through the liquid injection channel and the through holes 521 on the liquid injection sleeve 52, and simultaneously realize the linkage expansion or contraction of all the inner balloons 4 and the outer balloon 1. As a preferred solution, the wall of the liquid injection sleeve 52 can be designed to be full of through holes 521 to maximize the flow efficiency and ensure the uniformity of pressure transmission.

[0058] The unit of the shock wave generating mechanism further includes an elastic element 7 arranged in the conductive channel 514. The elastic element 7 is configured to apply an elastic force to the connecting core 6 to make it away from the conductive lining core 8, so that the connecting core 6 remains in the initial position when not under pressure. The elastic element 7 includes but is not limited to a spring.

[0059] The sliding direction of the connecting core 6 is consistent with the radial direction of the catheter, as shown in Figures 4 to 7As shown, it comprises a main body 61 and a blocking part 62 arranged at one end of the main body 61. The elastic element 7 is sleeved on the main body 61 and acts on the blocking part 62. The shock wave generating device is arranged on the main body 61, which can be a shock wave electrode, and the specific structure can refer to the prior art in the art. As an example, the shock wave electrode can be a conical electrode, which can concentrate discharge energy at the tip to form a directional shock wave beam. Experiments show that the shock wave compression amplitude generated by the conical electrode is 15%~20% higher than that of the flat electrode, and the discharge stability is better; it can also be an ellipsoidal discharge ball, which can slow down the electrode loss and stabilize the focusing point by designing the electrode as an ellipsoidal shape. The integrated structure of the discharge ball and the vibrating body can improve the shock wave energy conversion efficiency to more than 85%; it can also be a multi-prism pyramid nano array electrode (such as a pyramid or a three-prism pyramid), which improves the energy control accuracy through the following mechanisms: 1) plasma channel directional guidance: the high electric field strength of the pyramid tip can induce discharge to occur preferentially at the pyramid apex, reducing the shock wave divergence angle from 30° to 15°; 2) enhanced cavitation effect: the micro flow field formed by the pyramid gap can accelerate liquid cavitation, making the shock wave pressure rise steepness increase by 18%, which is suitable for layer-by-layer peeling of hard calcified lesions. The electrode can be specifically optimized in structure according to different degrees of calcified lesions.

[0060] The conductive liner core 8 is a hollow structure, and its distal end is connected to a liner balloon 84. The inner cavity of the liner balloon 84 is directly communicated with the hollow cavity 85 of the conductive liner core 8, thereby forming an independent fluid passage. By injecting or pumping inflation medium into the hollow cavity 85, the inflation or contraction of the liner balloon 84 can be remotely controlled. When the liner balloon 84 is filled with inflation medium, its outer diameter can be expanded to form a sealed contact with the inner wall of the inner tube 2 or the inner wall of the end cap 9 arranged at the distal end of the catheter, thereby being able to completely block the blood flow in the inner tube 2. In order to ensure electrical safety, the outer body of the conductive liner core 8 is covered with an insulating layer, and only at specific circumferential and axial positions of the conductive liner core 8, there are local metal exposed areas corresponding in shape and position to the end of the connecting core 6. When the connecting core 6 moves to the trigger position under pressure driving, its end will exactly make physical contact with the local metal exposed area on the conductive liner core 8, thereby forming a point-to-point precise electrical connection to complete power supply and triggering.

[0061] As preferred, a gap for circulating cooling medium to flow in or out is reserved between the outer wall of the conductive liner 8 and the inner wall of the inner tube 2. Specifically, the conductive liner 8 comprises a liner body 81, a first sector-shaped boss 82 and a second sector-shaped boss 83. The liner body 81 is in a cylindrical shape and has a hollow cavity 85 inside; the first sector-shaped boss 82 and the second sector-shaped boss 83 are respectively arranged on two sides of the liner body 81; the outer edge contour of the first sector-shaped boss 82 and the second sector-shaped boss 83 and the outer edge contour of the liner body 81 together define the gap. When the conductive liner 8 is placed in the inner tube 2, a non-uniform gap for the circulating cooling medium to flow through efficiently is naturally formed between the outer wall of the conductive liner 8 and the inner wall of the inner tube 2. The circulating cooling medium is preferably ultrapure water, which has very low ion content and can efficiently take away a large amount of heat generated by the shock wave generating device during operation to realize active water cooling circulation and temperature reduction of the conductive liner 8 and related components while ensuring absolute insulation and not causing electric leakage or short circuit. In addition, the local metal exposed area is arranged on the first sector-shaped boss 82 and / or the second sector-shaped boss 83, and the rotation of the conductive liner 8 can also determine the narrow position.

[0062] The above embodiments are only for illustrating the technical concept and characteristics of the present application, and the purpose is to enable those skilled in the art to understand the content of the present application and implement it, and cannot limit the protection scope of the present application. Any equivalent changes or modifications made according to the spirit and essence of the present application shall be covered within the protection scope of the present application.

Claims

1. A drug-eluting balloon catheter, comprising an inner tube (2), an outer tube (3) sleeved outside the inner tube (2), and an outer balloon (1) disposed at the distal ends of the outer tube (3) and the inner tube (2), wherein a fluid channel communicating with the outer balloon (1) is formed between the inner tube (2) and the outer tube (3); characterized in that, Also includes: Multiple inner balloons (4) are evenly arranged circumferentially inside the outer balloon (1); The connecting mechanism (5) has multiple independent connections that correspond one-to-one with the inner balloon (4). Each connecting mechanism (5) has an injection channel that connects the corresponding inner balloon (4) to the fluid channel and a conductive channel (514) that connects the corresponding inner balloon (4) to the inner cavity of the inner tube (2). The shock wave generating mechanism has multiple units corresponding one-to-one with the inner balloon (4). Each unit includes a connecting core (6) disposed in the conductive channel (514) and a shock wave generating device disposed on the connecting core (6). The connecting core (6) is slidably sealed with the conductive channel (514) so ​​that the inner balloon (4) and the inner cavity of the inner tube (2) are always isolated. A conductive liner (8) is movably disposed inside the inner tube (2); The outer balloon (1) comprises, from the inside out, a barrier layer, a drug reservoir containing therapeutic drugs, and a controlled-release outer layer, wherein the controlled-release outer layer has multiple channels distributed thereon. The drug-eluting balloon catheter is configured such that when the outer balloon (1) in the inflated working state is subjected to local compression, the inner balloon (4) at the corresponding position is compressed, driving the corresponding connecting core (6) to move toward the conductive liner (8) and form an electrical contact, thereby triggering the corresponding shock wave generator to generate a shock wave. The shock wave acts on the controlled-release outer layer of the locally compressed area on the outer balloon (1), causing the pores in that area to open or enlarge, thereby targeting and releasing the drug.

2. The drug-eluting balloon catheter according to claim 1, characterized in that, When the inner balloon (4) is in the inflated working state, its outer wall is in contact with the inner wall of the outer balloon (1), and its sidewall is in contact with the adjacent inner balloon (4).

3. The drug-eluting balloon catheter according to claim 1, characterized in that, The controlled-release outer layer is configured such that, when not subjected to the shock wave, the channels are closed or minimized to impede drug release.

4. The drug-eluting balloon catheter according to claim 1, characterized in that, The shock wave generating device is a shock wave electrode.

5. The drug-eluting balloon catheter according to claim 1, characterized in that, The sliding direction of the connecting core (6) is consistent with the radial direction of the inner tube (2).

6. The drug-eluting balloon catheter according to claim 1, characterized in that, The plurality of inner balloons (4) are arranged in multiple groups along the axial direction of the catheter; each group contains a plurality of inner balloons (4) evenly arranged in the circumferential direction, and the number of inner balloons (4) in each group may be the same or different.

7. The drug-eluting balloon catheter according to claim 1, characterized in that, The connecting mechanism (5) includes a connecting seat (51) and an injection sleeve (52); The connecting seat (51) includes a first seat (511) disposed on the inner wall of the inner tube (2), a second seat (512) disposed inside the corresponding inner balloon (4), and a tube (513) connecting the first seat (511) and the second seat (512). The tube (513) has a through inner cavity, which constitutes the conductive channel (514). The injection sleeve (52) is sleeved on the outside of the tube (513), and the corresponding inner balloon (4) is fixedly connected to the outer surface of the injection sleeve (52). The gap between the injection sleeve (52) and the tube (513) forms the injection channel. Multiple through holes (521) are distributed on the tube wall of the injection sleeve (52), some of which are located inside the corresponding inner balloon (4), and other through holes (521) are located outside the corresponding inner balloon (4).

8. The drug-eluting balloon catheter according to claim 1, characterized in that, The unit also includes an elastic element (7) disposed within the conductive channel (514), the elastic element (7) being configured to apply an elastic force to the connecting core (6) to move it away from the conductive liner (8), thereby holding the connecting core (6) in its initial position when not under pressure.

9. The drug-eluting balloon catheter according to claim 8, characterized in that, The connecting core (6) includes a main body (61) and a sealing part (62) disposed at one end of the main body (61). The elastic element (7) is sleeved on the main body (61) and acts on the sealing part (62).

10. The drug-eluting balloon catheter according to claim 1, characterized in that, The conductive core (8) is a hollow structure, and its distal end is connected to the core bladder (84). The core bladder (84) is connected to the hollow cavity (85) of the conductive core (8).

11. The drug-eluting balloon catheter according to claim 10, characterized in that, There is a gap between the conductive liner (8) and the inner tube (2) for the circulation cooling medium to enter or exit.

12. The drug-eluting balloon catheter according to claim 1, characterized in that, The conductive core (8) includes a cylindrical core body (81) and one or more bosses disposed on the periphery of the core body (81).

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