Cutter for intravascular cutting, balloon catheter and intravascular cutting device

Abstract

The utility model belongs to the technical field of medical instruments, and particularly relates to a cutter for intravascular cutting, a balloon catheter and an intravascular cutting device. The cutter is divided into a mounting part at the bottom and a cutting part at the top; the cutter is provided with a radial section in the height direction of the cutter, and in the radial section, the mounting part is arranged in a trapezoid shape, and the cutting part is arranged in a triangular shape. Compared with the prior art, the cutter has the advantages that connection stability is guaranteed, good cutting performance can be achieved, and meanwhile the cutter is compact in structure, small in occupied space, convenient to operate in specific environments (such as narrow spaces of blood vessels and the like) and the like.

Description

Technical Field

[0001] The utility model belongs to the technical field of medical devices, and particularly relates to a cutting tool for intravascular use, a balloon catheter and an intravascular cutting device. Background Art

[0002] Vascular intervention therapy is an important treatment method for revascularization of vascular stenosis lesions. In vascular intervention therapy, a balloon catheter is usually used as the main vascular intervention treatment instrument. For some intravascular stenosis lesions, such as fibrosis, mild to moderate calcification lesions and other stenosis lesions, an ordinary balloon catheter cannot effectively dilate the stenosis lesion site.

[0003] Cutting balloon angioplasty is an interventional treatment method developed on the basis of traditional balloon intracavitary angioplasty. It is a method similar to but not exactly the same as rotational ablation. It mainly uses a balloon with micro blades to expand and cut atherosclerotic plaques on the inner wall of blood vessels. Conventional balloons cannot expand hard lesions such as calcification, while cutting balloons often achieve good clinical effects. The cutting balloon is installed with several rows of blades in the axial direction on the outer circumferential surface of the balloon. When the balloon expands, the blades contact the lesion, thereby cutting the lesion and reducing the elastic recoil after the lesion is expanded. However, due to the presence of blades and blade bases in the existing cutting balloons, the diameter of the balloon is relatively large after folding. When dealing with stenosis lesions, its passing ability is poor, and generally, it needs to be pretreated with other instruments. At the same time, the blade material is made of stainless steel, with a relatively high hardness and fixed on the balloon. Because of the sharp and inflexible characteristics of the blade edge, it cannot pass through tortuous blood vessel parts during the transportation process and is not suitable for dealing with tortuous lesions.

[0004] Regarding another vascular disease, intimal hyperplasia is closely related to vascular remodeling diseases. Vascular remodeling diseases refer to cardiovascular diseases caused by arteriovenous fistulas, implantation of artificial blood vessels, or endothelial injury, vascular wall thickening and lumen stenosis caused by balloon dilation or stent implantation.

[0005] For ordinary vascular stenosis lesions, a balloon catheter is usually used to dilate the lesion tissue to restore blood flow in the blood vessels. Since most of the components in ordinary plaques are lipid substances, balloon treatment can often flatten the plaques. However, the tissue of intimal hyperplasia is more of newly generated smooth muscle cells and the extracellular matrix secreted by them. Balloon dilation treatment often results in immediate elastic recoil. Therefore, this treatment often cooperates with the use of vascular stents. The stent can stretch smooth muscle cells in the blood vessels under pressure to better improve vascular function. For lesions with severe vascular stenosis, the hyperplastic intima needs to be resected to restore lumen blood flow. This process usually involves cutting the blood vessels at the stenosis lesion site and scraping the hyperplastic part with a scalpel to restore lumen blood flow. However, this process has a large surgical trauma and is likely to increase the pain burden on patients.

[0006] Based on this, in the present utility model, a novel tool for intravascular cutting, a balloon catheter, and an intravascular cutting device are provided to overcome the above defects. Content of the Utility Model

[0007] The first object of the present utility model is to provide a tool for intravascular cutting, which enables good tortuous blood vessels, stenosis lesions, and passing ability in the human body, and has a good cutting effect on angulated calcified lesions.

[0008] The present utility model adopts the following technical solutions: A tool for intravascular cutting, the tool is divided into a bottom mounting part and a top cutting part;

[0009] Along the height direction of the tool, the tool has a radial cross-section. In the radial cross-section, the mounting part is trapezoidally arranged, and the cutting part is triangularly arranged.

[0010] Further, both bottom corners of the mounting part are rounded.

[0011] Further, the tip of the cutting part is edge-ground, either single-sided or double-sided.

[0012] Further, the side of the triangle of the cutting part is a ground surface, and the edge-ground part at the tip is a polished surface, and the precision of the polished surface is higher than that of the ground surface.

[0013] Further, from the radial cross-section of the tool, the outer angle θ formed by the trapezoidal side of the mounting part and the triangular side of the cutting part 2 has an angular value of 160° - 200°;

[0014] and / or from the radial cross-section of the tool, the included angle θ formed by the tip of the cutting part 1 has an angular value of 10° - 80°.

[0015] Further, from the radial cross-section of the tool, the tool is a left-right symmetric structure.

[0016] Further, a concave arc surface is provided on the end face of the mounting part of the tool away from the cutting part.

[0017] Further, the height H of the tool is 0.05 mm - 0.8 mm;

[0018] The bottom width L of the tool is 0.1 mm - 2 mm;

[0019] The triangular height h of the cutting part of the tool is 0.025 mm - 0.5 mm.

[0020] Compared with the prior art, the beneficial effects of the present utility model are as follows:

[0021] In the present utility model, the tool for intravascular cutting, viewed from the radial cross-section, is divided into a trapezoidal mounting portion and a triangular cutting portion. The mounting portion is used to connect with the balloon body, and is trapezoidally arranged, which helps to provide a more stable mounting foundation, is more firmly connected with the balloon body, and is not easily loosened and displaced during the operation; at the same time, it can better disperse the stress at the connection part, making the connection more reliable.

[0022] The cutting portion is used for cutting lesions, is triangularly arranged, has a relatively sharp vertex, can perform cutting operations more effectively, improves the treatment efficiency of the lesion site; and also helps to provide a certain guiding property during cutting, making the cutting more precisely along the expected direction, realizing precise guidance; at the same time, the triangular structure has a simple shape, is beneficial to manufacturing and processing, and can achieve a good cutting effect during use.

[0023] It can be seen that the tool in the present utility model not only ensures the stability of the connection, but also can achieve good cutting performance. At the same time, it also has the advantages of a compact structure, small occupied space, and being convenient to operate in a specific environment (such as a narrow space like a blood vessel).

[0024] The second object of the present utility model is to provide a balloon catheter. The present utility model adopts the following technical solutions:

[0025] It includes a balloon body, a catheter connected to the balloon body, and a plurality of tools installed at intervals along the circumferential direction of the balloon body. The tools extend along the length direction of the balloon body, and the tools are the above-mentioned tools for intravascular cutting.

[0026] The third object of the present utility model is to provide an intravascular cutting device, which is a device that can enter small and tortuous areas of blood vessels and can remove tissue and / or other obstructive materials from the blood vessels in a controlled manner; the following technical solutions are adopted in the present utility model:

[0027] It includes an elongated member, an operating portion connected to the elongated member, and a plurality of tools installed at the distal end of the elongated member. The tools are the above-mentioned tools for intravascular cutting. Description of the Drawings

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present utility model or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present utility model. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0029] Figure 1 The first structural schematic diagram of the tool for intravascular cutting in the specific embodiment of the present utility model;

[0030] Figure 2 The second structural schematic diagram of the tool for intravascular cutting in the specific embodiment of the present utility model;

[0031] Figure 3 The third structural schematic diagram of the tool for intravascular cutting in the specific embodiment of the present utility model;

[0032] Figure 4 The fourth structural schematic diagram of the tool for intravascular cutting in the specific embodiment of the present utility model;

[0033] Figure 5 The enlarged partial structure schematic diagram of the tool for intravascular cutting with single-sided edge opening in the specific embodiment of the present utility model;

[0034] Figure 6 The enlarged partial structure schematic diagram of the tool for intravascular cutting with double-sided edge opening in the specific embodiment of the present utility model;

[0035] Figure 7 The structural schematic diagram of the tool for intravascular cutting with a concave arc surface at the bottom in the specific embodiment of the present utility model;

[0036] Figure 8 The structural schematic diagram of a balloon catheter of the present utility model;

[0037] Figure 9 is Figure 8 the cross-sectional view at the balloon body in

[0038] Figure 10 The structural schematic diagram of an intravascular cutting device of the present utility model;

[0039] Wherein: tool 1, mounting part 10, concave arc surface 101, cutting part 11, tip 111; balloon body 2; slender member 3; operation part 4; protective sleeve 5. Detailed implementation manners

[0040] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described in conjunction with the accompanying drawings in the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all of the embodiments. Based on the embodiments in the present utility model, all other embodiments obtained by those of ordinary skill in the art without making creative efforts belong to the protection scope of the present utility model.

[0041] Next, in conjunction with the attached Figure 1 to the attached Figure 10 and specific embodiments, the present utility model will be described in detail:

[0042] As shown Figures 1-7 in the figure, the present utility model provides a tool for intravascular cutting, which can be used to cut fibrotic lesions, calcified plaques in blood vessels, cut the intima of blood vessels, and can also be used alone or loaded on the surface of a balloon as a cutting balloon.

[0043] The tool 1 is divided into a mounting part 10 provided at the bottom and a cutting part 11 provided at the top. The mounting part 10 is used for fixedly connecting with the balloon body 2, and the cutting part 11 is used for cutting lesions. And the mounting part 10 and the cutting part 11 are fixedly connected together. In the present utility model, the specific connection manner between the mounting part 10 and the cutting part 11 is not limited, and it can be integrally formed, welded, bonded, etc., all of which belong to the protection scope of the present utility model;

[0044] Along the height direction of the tool 1, the tool 1 has a radial cross-section. In the radial cross-section, the tool 1 can be in the shape of a wedge, a triangle, a triangular-shaped deformable body, etc. Specifically, the mounting part 10 is trapezoidally arranged, and the cutting part 11 is triangularly arranged.

[0045] For the tool for intravascular cutting in the present utility model, from the perspective of the radial cross-section, the tool 1 is divided into a trapezoidal mounting part 10 and a triangular cutting part 11. The mounting part 10 is used for connecting with the balloon body 2 and is trapezoidally arranged, which helps to provide a more stable mounting foundation, is more firmly connected with the balloon body 2, and is not easy to loosen and shift during the operation; at the same time, it can better disperse the stress at the connection part and make the connection more reliable.

[0046] The cutting part 11 is used for cutting lesions and is triangularly arranged, with a relatively sharp vertex, which can perform cutting operations more effectively, improve the treatment efficiency of the lesion site; it also helps to provide a certain guiding property during cutting, so that the cutting is more accurately along the expected direction to achieve precise guidance; at the same time, the triangular structure has a simple shape, which is beneficial to manufacturing and processing, and can achieve a good cutting effect during use.

[0047] It can be seen that for the tool in the present utility model, it not only ensures the stability of the connection, but also can achieve good cutting performance. At the same time, it also has the advantages of a compact structure, small occupied space, and being convenient to operate in a specific environment (such as a narrow space like a blood vessel).

[0048] Furthermore, since when the cutting balloon expands the angulated lesion, the stress points at both ends of the cutting parts such as the tool in contact with the blood vessel are the largest, and it is extremely easy to cause adverse events such as over-cutting resulting in blood vessel injury and perforation at this place. Therefore, in some specific embodiments, both bottom corners of the mounting part 10 are designed as rounded corners, such as Figure 1 、 2, as shown in Figures 3, it improves the reliability, safety and service life of the tool. Designing the two bottom corners of the installation part 10 as a rounded corner structure has the following advantages:

[0049] a. Reducing stress concentration: At the connection part between the installation part 10 and the balloon body 2, the rounded corners can relieve stress concentration and reduce the risk of rupture or damage caused by stress concentration during use.

[0050] b. Increasing connection strength: The design of the rounded corners can increase the contact area of the connection part and improve the connection strength between the installation part 10 and the balloon body 2.

[0051] c. Avoiding scratches: Sharp corners may cause scratches to other components or tissues during installation or use, while rounded corners can reduce this risk.

[0052] d. Improving appearance: The rounded corners can make the overall tool look more rounded and smooth, improving the appearance quality.

[0053] e. Facilitating manufacturing: Manufacturing the installation part 10 with rounded corners is relatively easier.

[0054] Furthermore, in some specific embodiments, the tip 111 of the cutting part 11 is ground, either unilaterally or bilaterally. Unilateral grinding means grinding only on one side of the blade to form a single-sided sharp blade, as Figure 5 shown, where the dashed line represents the tip before grinding and the solid line represents the tip after unilateral grinding; bilateral grinding is grinding on both sides of the blade to form a double-sided sharp blade, as Figure 6 shown, where the dashed line represents the tip before grinding and the solid line represents the tip after bilateral grinding. Unilateral grinding: The blade is relatively thin and has strong cutting ability, and can cut objects more easily, but the unilaterally ground blade is also relatively fragile and prone to wear and damage. Bilateral grinding: The blade is more durable and not easily worn and damaged. At the same time, the bilaterally ground blade is also more balanced and more stable to use. However, the bilaterally ground blade is relatively thicker and its cutting ability may be inferior to that of the unilaterally ground blade. Therefore, users can choose unilateral grinding or bilateral grinding according to actual needs in actual applications.

[0055] The grinding process mainly sharpens the blade edge by grinding. The purpose of grinding the blade edge is to form a fine V-shaped or U-shaped cutting edge on the blade so that the blade can cut objects more easily. Generally speaking, the smaller the angle of the blade, the sharper the cutting edge, but it is also more prone to wear. In this embodiment, the grinding angle θ 3 of the tip 111 of the cutting part 11 is 0 to 10°, which has strong practicability.

[0056] The edge-opening steps can be processed by conventional methods, specifically including: 1) Rough-grinding the blade with a coarse grinding stone or grinding tool, maintaining a certain angle and pressure, and grinding the blade until a preliminary cutting edge is formed; 2) Fine-grinding the blade with a fine grinding stone or sandpaper to further improve the sharpness and smoothness of the cutting edge; 3) Finally, polishing the blade with a fine grinding stone or sandpaper to ensure the smoothness and sharpness of the cutting edge.

[0057] Specifically, the side edges of the triangular cutting part 11 are grinding surfaces, and the edge-opening part of the tip 111 is a polishing surface, and the precision of the polishing surface is higher than that of the grinding surface. The grinding surface can reduce the roughness of the cutting opening caused by the cutting part 11, improve the sharpness, improve the cutting efficiency, and reduce the damage to blood vessels by the cutting surface.

[0058] Furthermore, in some specific embodiments, when viewed from the radial cross-section of the tool 1, the tool 1 has a left-right symmetric structure. The tool 1 having a left-right symmetric structure makes the forces on the left and right sides more uniform during operation, enables the tool to run more smoothly, and reduces unstable conditions such as deflection and jitter caused by uneven forces; it also helps to improve the accuracy and repeatability of tool operation, making the tool perform more consistently in various actions and usage scenarios. In addition, the symmetric structure usually has good mechanical properties, can enhance the overall strength and rigidity of the tool, and enable it to better withstand various stresses during work.

[0059] Furthermore, in some specific embodiments, when viewed from the radial cross-section of the tool 1, the outer angle θ formed by the trapezoidal side of the mounting part 10 and the triangular side of the cutting part 11 2 has an angular value of 160° - 200°. Correspondingly, limiting the angular value of the outer angle θ 2 has the following advantages:

[0060] a. Optimize mechanical distribution: Such an angular range helps to reasonably distribute the stresses received by the tool during use, makes the structure of the tool more stable during work, and reduces the risk of deformation or damage;

[0061] b. Adapt to operation requirements: Ensure that the tool can play a role in a more appropriate posture and angle when cooperating with the balloon body or performing operations, and adapt to specific application scenarios and operation requirements.

[0062] And / or when viewed from the radial cross-section of the tool 1, the tip 111 of the cutting part 11 forms an included angle θ 1 with an angular value of 10° - 80°. In this embodiment, θ 1 is about 30°. Correspondingly, limiting the angular value of the outer angle θ 1 has the following advantages:

[0063] a. Cutting performance balance: A smaller angle (e.g., close to 10°) may be suitable for finer and shallower cuts, while a larger angle (close to 80°) may be more advantageous when greater cutting force or a wider cutting range is required, providing a certain degree of flexibility in cutting performance under different circumstances.

[0064] b. Controlling cutting effect: Different included angles can achieve different degrees of sharpness and cutting depth control, facilitating adjustment according to specific operating purposes.

[0065] c. Reducing resistance: A suitable included angle helps reduce resistance during cutting, improving operating efficiency and smoothness.

[0066] Furthermore, in order to improve the stability of the tool 1 on the surface of the balloon body 2 and effectively reduce the risk of damage to the balloon body 2 by the tool 1, in some specific embodiments, a concave arc surface 101 is provided on the end face of the mounting portion 10 of the tool 1 away from the cutting portion 11. By providing the concave arc surface 101 on the side of the tool 1 close to the balloon body 2, it has the following advantages:

[0067] 1) Enhanced stability: The concave arc surface 101 can better fit the surface of the balloon body 2, increasing the contact area, thereby improving the stability of the installation of the tool 1 on the balloon body 2 and reducing the possibility of the tool shaking or shifting during operation.

[0068] 2) Pressure dispersion: The concave arc surface 101 can make the force exerted by the tool 1 more evenly distributed on the surface of the balloon body 2, reducing local pressure concentration, and thus reducing the risk of damage to the balloon body 2.

[0069] 3) Improving contact form: It helps to optimize the contact mode between the tool 1 and the balloon body 2, making the interaction smoother and more natural, and reducing the possibility of damage caused by sharp contact or inappropriate contact.

[0070] Specifically, in this embodiment, the fillet value R of the concave arc surface 101 at the bottom of the mounting portion 10 1 > 0.03 mm.

[0071] Furthermore, the tool 1 is made of a superelastic alloy or elastic material, the Young's modulus of the tool 1 is designed to be greater than or equal to 15 GPa, and the breaking tensile force of the tool 1 is greater than or equal to 4.5 N. Among them, the Young's modulus is a physical quantity of the mechanical properties of materials, used to measure the deformation per unit area of a substance under axial force. The Young's modulus, also known as the elastic modulus or elastic coefficient, refers to the degree of elastic deformation of a material under axial force, that is, the ratio of the amount of deformation to the force causing the deformation. The breaking strength is the ratio of the tensile force at which a material breaks to the cross-sectional area at the break, that is, the stress.

[0072] In a specific embodiment, the cutting tool 1 is made of NiTi alloy material. In order to improve the properties such as elasticity of the cutting tool 1, other elements can be added to the NiTi alloy.

[0073] The advantages of adopting such a design of Young's modulus and fracture tensile force are as follows:

[0074] a. Improve the cutting efficiency: The Young's modulus of the cutting tool 1 is greater than or equal to 15 GPa, which can improve the cutting efficiency of the flexible cutting balloon, make the cutting tool 1 harder and more durable, and be able to better cut hard masses and plaques in blood vessels.

[0075] b. Improve the safety: The fracture tensile force of the cutting tool 1 is greater than or equal to 4.5 N, which can make the flexible cutting balloon cut the plaque at a higher pressure, reduce the risk of fracture and damage of the cutting components of the flexible cutting balloon, and improve the safety.

[0076] More preferably, within the bending range of 180° to 20° of the cutting tool 1, the stress-strain curves during loading and unloading forces thereof basically coincide. When the curvature K is less than or equal to 0.083 during bending, the stress-strain curve begins to change from linear to non-linear.

[0077] The suitable superelastic performance of the cutting tool 1 enables the cutting unit to be deformed more easily, and the deformation energy can increase slowly and tend to be gentle as the deformation increases rapidly. That is, compared with the traditional cutting balloon, the elastic modulus of the cutting tool 1 of this balloon is lower, and after the stress and strain reach a certain degree of bending, a non-linear relationship is presented. When the strain continuously increases, the stress fluctuation is very small. That is, when the cutting tool 1 is applied to the balloon catheter, when the balloon catheter undergoes bending deformation of various arcs due to conforming to the vascular anatomical structure during the pushing and expanding processes, the force acting on the blood vessel wall changes very little, and it can smoothly pass through various curved and tortuous blood vessels.

[0078] Furthermore, based on the structure of the cutting tool 1 above, the applicant found that whether the cutting tool 1 is rigid or elastic, due to the tip 111 being relatively sharp, when expanding blood vessels of different sizes, it is still inevitable to cut the tunica media and adventitia of the blood vessel. Therefore, in this embodiment, the structure of the cutting tool 1 is further improved.

[0079] The applicant conducted a large number of creative experiments and found that during the process of balloon cutting of blood vessels, the height H of the cutting tool 1 is a very crucial factor. If the height H of the cutting tool 1 is relatively low and has a sharp shape, then even when the balloon has expanded to a certain extent, it is very difficult to cut the tunica media and adventitia of the blood vessel. This is because the tunica media and adventitia tissues of the blood vessel are relatively tough and can be pushed outward under the pressure of the balloon, thus avoiding being damaged by the cutting tool 1.

[0080] However, if the height H of the cutting tool 1 is relatively high, then it is necessary to appropriately reduce the sharpness to avoid too deep incisions after dilation and damage to the tunica media and adventitia tissues. This is because when the height of the cutting tool is relatively high, its sharp shape may form overly sharp edges, which will increase the risk of damage to the blood vessel during the cutting process by the balloon. Therefore, to avoid this situation, the sharpness of the cutting component can be appropriately reduced to reduce the risk of damage to the blood vessel. In summary, it can be seen that there is a certain negative correlation between the height H of the cutting tool 1 and the included angle θ of the tip 111 of the cutting tool 1 1 shows a certain negative correlation.

[0081] Meanwhile, the height H of the cutting tool 1 is determined according to the expected blood vessel diameter and lesion conditions, adapting to different lesion depths and ranges to ensure the treatment effect; enabling this cutting tool 1 to be applicable to dilation cutting treatments of various sizes and blood vessel diameters, ensuring a good cutting effect on plaques while avoiding additional cutting or tearing effects on the normal tunica media and adventitia tissues of the blood vessel, causing excessive damage to the blood vessel and leading to the occurrence of thrombosis and restenosis.

[0082] In a specific embodiment, the size range of the cutting tool 1 is given:

[0083] The height H of the cutting tool 1 is 0.05 mm to 0.8 mm;

[0084] The bottom width L of the cutting tool 1 is 0.1 mm to 2 mm, and the optimal value is 0.22 mm;

[0085] The triangular height h of the cutting part 11 of the cutting tool 1 is 0.025 mm to 0.5 mm, and the best value is 0.12 mm to 0.15 mm. The triangle is the main cutting part 11. During cutting, the triangular part enters the lesion, and the deepest part of the triangle reaches the tunica media of the blood vessel.

[0086] The cutting tool 1 manufactured according to this size, compared with the cutting edge of the traditional cutting balloon, shows a negative correlation between the set height and the tip edge opening angle of the cutting tool 1. In different types of blood vessels, a reasonable cutting tool can be selected according to the actual situation to avoid damaging normal blood vessel tissues such as the tunica media and adventitia, while retaining a good cutting effect on hard plaques.

[0087] Based on the above-mentioned cutting tool for blood vessel internal cutting, the present utility model further provides a balloon catheter, as Figure 8 、 9 shown. This balloon catheter includes a balloon body 2, a catheter connected to the balloon body 2, and a plurality of cutting tools 1 installed at intervals along the circumferential direction of the balloon body 2. The cutting tools 1 extend along the length direction of the balloon body 2. The cutting tools are the above-mentioned cutting tools for blood vessel internal cutting and have all the advantages of the above-mentioned cutting tools for blood vessel internal cutting, which will not be elaborated here.

[0088] In this embodiment, the cutting tool 1 is made of a superelastic alloy material. The height H of the cutting tool 1 is 0.2 mm, the width L of the cutting tool 1 is 0.2 mm, and the included angle θ of the tip 111 of the cutting part 11 1 is 30°. The length is adapted to the length of the balloon body 2, which is 15 mm. A total of three cutting tools 1 are installed and evenly distributed on the surface of the balloon body 2 at 120 degrees.

[0089] During use, physiological saline is filled into the inner tube, and the pressure on the balloon body 2 is increased to 4 atmospheres, causing the balloon body 2 to expand, thereby pushing the cutting tool 1 to cut the vascular calcified plaque. At the same time, the balloon body 2 dilates the blood vessel. When the pressure is increased to 12 atmospheres, the calcified lesion is completely opened, thereby expanding the passage diameter of the blood vessel. Then, the pressure on the balloon body 2 is gradually removed, and the cutting tool 1 returns to its original shape, and there is no visible damage at the fixed point.

[0090] Based on the above-mentioned cutting tool for intravascular cutting, the present utility model further provides an intravascular cutting device, as Figure 10 shown. The intravascular cutting device can enter small and tortuous areas of blood vessels and can remove tissue and / or other obstructive materials from blood vessels in a controlled manner. The intravascular cutting device includes an elongated member 3, an operating part 4 connected to the elongated member 3, and a plurality of cutting tools installed at the distal end of the elongated member 3. The cutting tools are the above-mentioned cutting tools for intravascular cutting.

[0091] Specifically, the cutting tool 1 is installed on a catheter or other elongated member 3. During use, a protective sleeve is put on the outside of the device, and the whole is introduced into the vascular target area from outside the body, and then the protective sleeve 5 is retracted to expose the cutting tool 1. Rotate the elongated member to drive the cutting tool 1 to rotate to cut the hyperplastic intima of the blood vessel. Or push and pull the elongated member to cut the hyperplastic intima of the blood vessel.

[0092] Although the above discussion is directed to an intravascular cutting device for cutting hyperplastic intima of blood vessels, it should be understood that the teachings of the present disclosure are equally applicable to cutting devices for removing tissue from blood vessels and penetrating occlusions in blood vessels, such as atherosclerotic or thrombotic occlusions, stenotic materials in arteries, or other occlusions in veins.

[0093] The above further describes the present utility model with the aid of specific embodiments. However, it should be understood that the specific description herein should not be construed as limiting the essence and scope of the present utility model. Various modifications made by those of ordinary skill in the art to the above embodiments after reading this specification all fall within the scope protected by the present utility model.

Claims

1. A knife for intravascular cutting, characterized in that: The cutter is divided into a mounting portion at the bottom and a cutting portion at the top; Along the height direction of the tool, the tool has a radial cross section, in which the mounting portion is arranged in a trapezoidal shape and the cutting portion is arranged in a triangular shape; The tip of the cutting part is sharpened, either single-sided or double-sided; the side of the triangle of the cutting part is a grinding surface, and the sharpening part of the tip is a polishing surface, and the precision of the polishing surface is higher than that of the grinding surface; A concave arc surface is arranged on the end surface of the tool mounting portion away from the cutting portion.

2. The intravascular cutting tool according to claim 1, characterized in that: Both bottom corners of the mounting portion are rounded.

3. The intravascular cutting tool according to claim 1, characterized in that: From the radial cross section of the tool, the angle value of the external angle θ2 formed by the trapezoidal side of the mounting portion and the triangular side of the cutting portion is 160° to 200°; And / or viewed from the radial cross section of the tool, the angle θ1 formed by the tip of the cutting portion has an angle value of 10° to 80°.

4. The intravascular cutting tool according to claim 1, characterized in that: From the radial cross section of the tool, the tool is a bilaterally symmetrical structure.

5. The intravascular cutting tool according to claim 1, characterized in that: The height H of the tool is 0.05 mm to 0.8 mm; The bottom width L of the tool is 0.1 mm to 2 mm; The triangle height h of the tool cutting portion is 0.025 mm to 0.5 mm.

6. A balloon catheter, characterized in that: It includes a balloon body, a catheter connected to the balloon body, and a plurality of cutters installed at intervals along the circumference of the balloon body. The cutters extend along the length direction of the balloon body, and the cutters are the intravascular cutting cutters as described in any one of claims 1 to 5.

7. An intravascular cutting device, characterized in that: It comprises a slender member, an operating part connected to the slender member, and a plurality of knives installed at the distal end of the slender member, wherein the knives are the intravascular cutting knives as claimed in any one of claims 1 to 5.

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