Coronary cutting balloon catheter with drug loading function

Abstract

The application discloses a coronary cutting balloon catheter with a drug loading function, and relates to the technical field of cutting balloon catheters, which comprises an outer tube, a balloon capable of being radially expanded is arranged at the distal end of the outer tube, an inner tube is coaxially arranged in the inner part of the outer tube, the distal end of the inner tube is fixedly connected with the distal end of the outer tube, a fluid channel is formed between the inner tube and the inner cavity of the balloon, an annular cavity between the inner tube and the outer tube forms an extension section of the fluid channel, a plurality of cutting knife assemblies are attached to the outer surface of the balloon, the distal end of the outer tube is further connected with a first knife guard ring and a second knife guard ring located at the two ends of the balloon, a plurality of knife guard pull belts corresponding to the cutting knife assemblies are connected between the first knife guard ring and the second knife guard ring, when the balloon is in a collapsed state, the knife guard pull belts correspondingly cover the cutting knife assemblies, when the balloon is radially expanded, the knife guard pull belts deviate from the cutting knife assemblies under the drive of the first knife guard ring and the second knife guard ring, and the safety is higher.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of cutting balloon catheters, and particularly relates to a coronary cutting balloon catheter with a drug loading function. BACKGROUND

[0002] Coronary artery disease is one of the most common diseases of the cardiovascular system, and its treatment technology has undergone evolution from simple balloon dilation, bare metal stent to drug-eluting stent. However, the treatment of complex lesions (such as calcified and fibrotic plaques) still faces challenges: traditional balloon dilation may cause elastic recoil, dissection or poor stent apposition, while stent implantation may cause intimal hyperplasia and late thrombosis risk. Therefore, cutting balloon catheters have emerged, which cut the plaque through micro-knives on the surface of the balloon during expansion to reduce the expansion pressure and improve the vessel compliance.

[0003] At present, coronary cutting balloon catheters mainly focus on the mechanical cutting performance of micro-knives. Although the single-knife design can reduce vascular trauma, the drug loading groove is usually designed in a simple linear arrangement due to the spatial layout of the single-knife structure, which leads to insufficient drug storage capacity and poor uniformity of drug distribution, making it difficult to form a stable drug concentration coverage in the lesion area. In addition, to ensure the deliverability of the coronary cutting balloon catheter in the blood vessel, the micro-knives need to maintain a very low profile when not expanded, but the interaction between the knife tip and the balloon material in this state may cause potential damage risk. Although the knives treated by passivation can reduce accidental scratches on the blood vessel wall during delivery, they will significantly weaken the cutting efficiency.

[0004] Therefore, it is necessary to provide a coronary cutting balloon catheter with a drug loading function to solve the above problems. SUMMARY

[0005] To solve the above problems, the present application provides the following technical scheme: a coronary cutting balloon catheter with a drug loading function, comprising:

[0006] an outer tube, a distal end of the outer tube being sealingly provided with a balloon that can be radially expanded;

[0007] an inner tube, the inner tube being coaxially sleeved inside the outer tube, a distal end of the inner tube being fixedly connected to the distal end of the outer tube, the inner tube and an inner cavity of the balloon forming a fluid passage, and an annular cavity between the inner tube and the outer tube constituting an extension section of the fluid passage;

[0008] a plurality of cutting knife assemblies, the cutting knife assemblies being attached to an outer surface of the balloon;

[0009] the distal end of the outer tube is further connected with a first knife guard ring and a second knife guard ring located at two ends of the balloon, a plurality of knife guard pull belts corresponding to the cutting knife assemblies are connected between the first knife guard ring and the second knife guard ring.

[0010] The guard pull belt corresponds to cover the cutting knife assembly when the balloon is in collapsed state, and the guard pull belt deviates from the cutting knife assembly under the drive of the first guard ring and the second guard ring when the balloon is radially expanded.

[0011] Further, as preferred, the cutting knife assembly comprises:

[0012] A knife seat attached to the outer surface of the balloon;

[0013] Two knife bodies arranged along the width direction of the knife seat, and the knife bodies are connected to the knife seat by support pads.

[0014] Further, as preferred, the side part of the knife body has a plurality of drug loading grooves arranged along the length direction of the knife body, and the corresponding drug loading grooves between the two knife bodies are used to carry drugs.

[0015] Further, as preferred, both the knife bodies can move along the length direction of the knife seat relative to the knife seat;

[0016] One end of one of the knife bodies is connected with an axial push balloon, the axial push balloon passes through the knife seat and communicates with the balloon, and when the axial push balloon is axially expanded, the knife body can be slightly moved along its length direction.

[0017] Further, as preferred, a transition part is formed between the end of the balloon and the inner tube, and the first guard ring and the second guard ring both partially cover the transition part;

[0018] A plurality of reset pads are connected between the first guard ring or the second guard ring and the outer tube, and the reset pads are arranged along the circumference of the first guard ring or the second guard ring.

[0019] Further, as preferred, a circumferential push balloon is connected between the first guard ring or the second guard ring and the balloon, the circumferential push balloon communicates with the balloon, and when the circumferential push balloon is circumferentially expanded, the first guard ring or the second guard ring can be circumferentially deflected.

[0020] Further, as preferred, the inner tube located inside the balloon is provided with a developing ring.

[0021] Further, as preferred, the outer surface of the balloon is provided with at least three groups of cutting knife assemblies arranged along the circumference of the outer tube, and each group has at least two cutting knife assemblies arranged along the length direction of the outer tube.

[0022] Further, as preferred, the guard pull belt is made of slow-rebound material.

[0023] Further, as preferred, the distance between the two cutter bodies on the cutter seat is 0.5-3mm.

[0024] Compared with the prior art, the coronary cutting balloon catheter with drug loading function has the following beneficial effects:

[0025] In the present application, during the delivery of the coronary cutting balloon catheter, the protective cutter pull belt covers the cutting knife assembly, effectively preventing accidental damage to the blood vessel wall by the cutting knife assembly before reaching the target position, and ensuring the safety of the operation.

[0026] In the present application, when the balloon is expanded, the protective cutter pull belt can smoothly deviate from the cutting knife assembly, ensuring that the cutting knife assembly can be fully exposed and accurately cut the diseased tissue on the blood vessel wall, improving the accuracy and efficiency of the operation.

[0027] In the present application, the double-cutter body design significantly improves the drug loading capacity compared to the single-cutter body design, allowing more drugs to be released to the treatment area while cutting the diseased tissue, thereby improving the treatment effect. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 is a front view structural schematic diagram of a coronary cutting balloon catheter with drug loading function;

[0029] Figure 2 is a front view structural schematic diagram of a cutting knife assembly in a coronary cutting balloon catheter with drug loading function;

[0030] Figure 3 is a mounting structure schematic diagram of a second protective cutter ring in a coronary cutting balloon catheter with drug loading function Figure 1 ;

[0031] Figure 4 is a mounting structure schematic diagram of a second protective cutter ring in a coronary cutting balloon catheter with drug loading function Figure 2 ;

[0032] In the figure: 1, outer tube; 2, inner tube; 3, developing ring; 4, balloon; 5, cutting knife assembly; 6, transition part; 7, first protective cutter ring; 8, second protective cutter ring; 9, protective cutter pull belt; 10, circumferential push balloon; 11, reset pad; 51, cutter seat; 52, support pad; 53, cutter body; 54, drug loading groove; 55, axial push balloon. DETAILED DESCRIPTION

[0033] The terms "first", "second", and the like, as used in the description and the claims of the present application and the above Summary are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the terms so used are interchangeable under appropriate circumstances such that the embodiments of the present application described herein are, for example, capable of use in either order. It is therefore intended that the application be interpreted in the broadest possible way consistent with the nature of the claims and the appended drawings.

[0034] Embodiment: Please refer to Figures 1-4 In the embodiments of the present application, a coronary cutting balloon catheter with drug loading function is provided, comprising:

[0035] an outer tube 1, a radially expandable balloon 4 is arranged at the distal end of the outer tube 1;

[0036] an inner tube 2, which is coaxially sleeved inside the outer tube 1, and the distal end of the inner tube 2 is fixedly connected with the distal end of the outer tube 1, the inner tube 2 and the inner cavity of the balloon 4 form a fluid channel, and the annular cavity between the inner tube 2 and the outer tube 1 constitutes an extension section of the fluid channel;

[0037] a plurality of cutting knife assemblies 5 attached to the outer surface of the balloon 4;

[0038] The distal end of the outer tube 1 is also connected with a first knife guard ring 7 and a second knife guard ring 8 located at both ends of the balloon 4, and a plurality of knife guard pull belts 9 corresponding to the cutting knife assemblies 5 are connected between the first knife guard ring 7 and the second knife guard ring 8;

[0039] When the balloon 4 is in a collapsed state, the knife guard pull belts 9 correspondingly cover the cutting knife assemblies 5, and when the balloon 4 is radially expanded, the knife guard pull belts 9 deviate from the cutting knife assemblies 5 under the drive of the first knife guard ring 7 and the second knife guard ring 8.

[0040] Therefore, in the implementation, the following steps are included:

[0041] Step one: In the unexpanded state, the coronary cutting balloon catheter is sent into the patient's vascular system by interventional surgery, such as percutaneous coronary intervention (PCI). At this time, the balloon 4 is in a collapsed state.

[0042] Step two: The cutting knife assemblies 5 are attached to the outer surface of the balloon 4, and the knife guard pull belts 9 cover the cutting knife assemblies 5 under the action of the first knife guard ring 7 and the second knife guard ring 8, forming a protective layer. It is ensured that the cutting knife assemblies 5 will not cause accidental damage to the healthy blood vessel wall along the way before the coronary cutting balloon catheter reaches the target lesion position.

[0043] Step three: Once the target position is reached, the balloon 4 is inflated by injecting fluid through the extension section of the fluid channel and into the balloon 4, causing the balloon 4 to expand radially. This not only expands the stenotic vessel region, but also prepares for the subsequent cutting operation.

[0044] Step four: With the expansion of the balloon 4, the first and second guard rings 7 and 8 drive the guard pull 9 to deviate from the cutting blade assembly 5. At this time, the cutting blade assembly 5 is exposed and can directly contact and cut the diseased tissue on the vessel wall.

[0045] Step five: After the cutting is completed, the injection of fluid into the balloon 4 is stopped, and the balloon 4 gradually collapses back to the initial state. At the same time, the first and second guard rings 7 and 8 and the guard pull 9 are reset to ensure that the blood vessel is not damaged again during the withdrawal of the coronary cutting balloon catheter.

[0046] That is, in this embodiment, the design of the guard pull 9 effectively prevents the accidental exposure of the cutting blade assembly 5 before reaching the target position, greatly reducing the risk of damage to the healthy vessel wall during the operation. Moreover, by precisely controlling the expansion and collapse of the balloon 4, the exposure and hiding of the cutting blade assembly 5 can be precisely controlled, thereby achieving precise cutting of the diseased tissue. The coronary cutting balloon catheter is suitable for the treatment of various coronary artery diseases, especially complex lesions that require precise cutting operations, such as calcified lesions.

[0047] In this embodiment, the cutting blade assembly 5 includes:

[0048] a blade seat 51 attached to the outer surface of the balloon 4;

[0049] two blade bodies 53 spaced apart along the width direction of the blade seat 51, the blade bodies 53 being connected to the blade seat 51 by support pads 52.

[0050] The side of the blade body 53 has a plurality of drug carrying grooves 54 spaced apart along the length direction of the blade body 53, and the corresponding drug carrying grooves 54 between the two blade bodies 53 are used to carry the drug.

[0051] In this embodiment, the two blade bodies 53 are spaced apart along the width direction of the blade seat 51, which not only ensures the stability and accuracy of the cutting operation, but also provides the possibility of increasing the drug load.

[0052] Specifically, the side of each blade body 53 is designed with a plurality of drug carrying grooves 54 spaced apart along its length direction. These drug carrying grooves 54 not only serve to accommodate the drug, but also allow additional drug to be carried between the corresponding drug carrying grooves 54 of the two blade bodies through their special design.

[0053] Therefore, during the balloon expansion process, as the cutter bodies 53 expand outward and contact the lesion, the drug bodies are released from the drug-loading grooves 54 along with the cutting of the cutter bodies 53, and act on the cutting surface. Due to the additional drug-loading space between the two cutter bodies 53, the amount of drug body release is increased, thereby improving the treatment effect.

[0054] Further, the distance between the two cutter bodies 53 on the cutter seat 51 is 0.5-3mm, which ensures that the cutter bodies 53 can remain stable during expansion, avoid mutual interference, and at the same time ensures the flatness and accuracy of the cutting surface. This distance also optimizes the space utilization between the drug-loading grooves 54, so that the additional carrying space between the two cutter bodies 53 is maximized. This not only increases the carrying capacity of the drug bodies, but also improves the release efficiency and uniformity of the drug bodies during cutting.

[0055] Further, both of the cutter bodies 53 can move relative to the cutter seat 51 along the length direction of the cutter seat 51;

[0056] One end of one of the cutter bodies 53 is connected with an axial push capsule 55, the axial push capsule 55 passes through the cutter seat 51 and communicates with the balloon 4, and when the axial push capsule 55 expands axially, it can push the cutter body 53 to move slightly along its length direction.

[0057] That is, in the present embodiment, both of the cutter bodies 53 can move relative to the cutter seat 51 along the length direction of the cutter seat 51, and an axial push capsule 55 is introduced and connected to one end of one of the cutter bodies 53. This design not only enhances the flexibility of the cutting knife assembly 5, but also realizes the dislocation of the drug-loading grooves 54 through the expansion of the axial push capsule 55, further improving the drug release efficiency.

[0058] In the present embodiment, a transition portion 6 is formed between the end of the balloon 4 and the inner tube 2, and the first cutter guard ring 7 and the second cutter guard ring 8 both partially cover the transition portion 6.

[0059] The first cutter guard ring 7 and the second cutter guard ring 8 are both connected with a plurality of reset pads 11 distributed along the circumference of the first cutter guard ring 7 or the second cutter guard ring 8 between the first cutter guard ring 7 and the second cutter guard ring 8 and the outer tube 1.

[0060] The first cutter guard ring 7 and the second cutter guard ring 8 are both connected with a circumferential push capsule 10 between the first cutter guard ring 7 and the second cutter guard ring 8 and the balloon 4, the circumferential push capsule 10 communicates with the balloon 4, and when the circumferential push capsule 10 expands circumferentially, it can push the first cutter guard ring 7 or the second cutter guard ring 8 to deflect circumferentially.

[0061] That is, once reaching the target position, the balloon 4 is radially expanded by injecting fluid into the balloon 4. With the expansion of the balloon 4, the circumferential push balloon 10 is also expanded, pushing the first and second cutter guard rings 7 and 8 to deflect circumferentially. This deflection helps the cutter guard pull tape 9 to more smoothly deviate from the cutting knife assembly 5, ensuring that the cutting knife assembly 5 can be fully exposed and contact the diseased tissue on the vessel wall. At the same time, due to the deflection of the cutter guard rings (the first and second cutter guard rings 7 and 8), the reset pad 11 is stretched, reserving potential energy for subsequent reset operation. After cutting is completed, the injection of fluid into the balloon 4 is stopped, and the balloon 4 and the circumferential push balloon 10 gradually collapse back to the initial state. With the collapse of the balloon 4 and the circumferential push balloon 10, the reset pad 11 releases the reserved potential energy, pushing the cutter guard rings to reset, and the cutter guard pull tape 9 re-covers the cutting knife assembly 5.

[0062] Further, the cutter guard pull tape 9 is made of slow-rebound material.

[0063] When fluid is injected into the balloon 4, the balloon 4 is radially expanded. With the expansion of the balloon 4, the circumferential push balloon 10 is also expanded, pushing the cutter guard rings to deflect circumferentially. This deflection causes the cutter guard pull tape 9 to gradually separate from the cutting knife assembly 5 under the drive of the cutter guard rings.

[0064] At the same time, since the cutter guard pull tape 9 is made of slow-rebound material, during the process of resetting the cutter guard rings, the cutter guard pull tape 9 can gradually recover its original shape and position to re-cover the cutting knife assembly 5. This recovery ensures that the cutter guard pull tape 9 will not cause secondary damage to the healthy vessel wall during the withdrawal of the catheter.

[0065] Further, before the coronary cutting balloon catheter is lowered, a lubricant is applied to the side surface of the cutting knife assembly 5 close to the cutter guard pull tape 9, thereby reducing the probability of the cutter guard pull tape 9 being stuck on the cutting knife assembly 5 and ensuring that it can be separated from the cutting knife assembly 5 under the drive of the cutter guard rings. In addition, it should be noted that the cutter guard pull tape 9 has a stretching limit. Generally, when the balloon 4 is radially expanded to the limit, the cutter guard pull tape 9 reaches the stretching limit.

[0066] In this embodiment, the inner tube 2 inside the balloon 4 is provided with a developing ring 3.

[0067] In this embodiment, the outer surface of the balloon 4 is provided with at least three groups of cutting knife assemblies 5 distributed circumferentially along the outer tube 1, each group being at least two cutting knife assemblies 5 distributed along the length direction of the outer tube 1, ensuring the comprehensiveness and uniformity of the cutting operation. This layout helps to achieve more thorough and uniform cutting of the diseased tissue.

[0068] The above merely describes preferred specific embodiments of the present application, but the protection scope of the present application is not limited thereto, and any person skilled in the art, according to the technical solution and inventive concept of the present application, makes equivalent replacement or change within the technical range disclosed by the present application, which should be covered within the protection scope of the present application.

Claims

1. A coronary cutting balloon catheter having a drug loading function, characterized in that, The application relates to a cutting balloon catheter. The application comprises: an outer tube (1) with a radially expandable balloon (4) at the distal end; an inner tube (2) coaxially sleeved in the outer tube (1), with the distal end fixedly connected to the distal end of the outer tube (1), the inner tube (2) and the inner cavity of the balloon (4) forming a fluid channel, and the annular cavity between the inner tube (2) and the outer tube (1) constituting an extension section of the fluid channel; a plurality of cutting blade assemblies (5) attached to the outer surface of the balloon (4); the distal end of the outer tube (1) is further connected with a first blade guard ring (7) and a second blade guard ring (8) at the two ends of the balloon (4), a plurality of blade guard pull belts (9) corresponding to the cutting blade assemblies (5) are connected between the first blade guard ring (7) and the second blade guard ring (8); when the balloon (4) is in a collapsed state, the blade guard pull belts (9) correspondingly cover the cutting blade assemblies (5), and when the balloon (4) is radially expanded, the blade guard pull belts (9) are driven by the first blade guard ring (7) and the second blade guard ring (8) to deviate from the cutting blade assemblies (5); a transition section (6) is formed between the end of the balloon (4) and the inner tube (2), and the first blade guard ring (7) and the second blade guard ring (8) both partially cover the transition section (6); a plurality of reset pads (11) are connected between the first blade guard ring (7) and the second blade guard ring (8) and the outer tube (1) and are distributed along the circumference of the first blade guard ring (7) or the second blade guard ring (8); 2. The coronary cutting balloon catheter with drug loading function according to claim 1, characterized in that, a circumferential balloon pushing belt (10) is connected between the first blade guard ring (7) and the second blade guard ring (8) and the balloon (4), the circumferential balloon pushing belt (10) communicates with the balloon (4) and can push the first blade guard ring (7) or the second blade guard ring (8) to deflect circumferentially when the circumferential balloon pushing belt (10) is expanded circumferentially. The cutting blade assembly (5) comprises: a blade seat (51) attached to the outer surface of the balloon (4); 3. The cutting balloon catheter according to claim 2, wherein the drug is a drug for treating atherosclerosis. two blade bodies (53) spaced along the width direction of the blade seat (51) and connected to the blade seat (51) by support pads (52).

4. The cutting balloon catheter according to claim 3, wherein the drug is a drug for treating atherosclerosis. The side of the blade body (53) is provided with a plurality of drug loading grooves (54) spaced along the length direction of the blade body (53), and the corresponding drug loading grooves (54) between the two blade bodies (53) are used for carrying drug bodies. Both the blade bodies (53) can move along the length direction of the blade seat (51) relative to the blade seat (51).

5. The cutting balloon catheter according to claim 1, wherein the balloon is coated with a drug. One end of one of the blade bodies (53) is connected with an axial balloon pushing belt (55), the axial balloon pushing belt (55) penetrates through the blade seat (51) and communicates with the balloon (4), and the blade body (53) can be slightly moved along the length direction when the axial balloon pushing belt (55) is axially expanded.

6. The cutting balloon catheter according to claim 1, wherein the balloon is made of a material having a drug loading function. The inner tube (2) in the balloon (4) is provided with a developing ring (3).

7. The cutting balloon catheter according to claim 1, wherein the balloon is coated with a drug. The outer surface of the balloon (4) is provided with at least three groups of cutting blade assemblies (5) spaced along the circumference of the outer tube (1), and each group is at least two cutting blade assemblies (5) spaced along the length direction of the outer tube (1). The blade guard pull belts (9) are made of slow-rebound material.

8. The cutting balloon catheter according to claim 2, wherein the balloon is coated with a drug. The distance between the two cutter bodies (53) on the cutter seat (51) is 0.5-3mm.

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