Cutting balloon catheter and preparation method thereof

Abstract

The present invention discloses a cutting balloon catheter and its preparation method, which relates to the field of medical device technology. The catheter comprises a balloon and a cutting assembly disposed on the outer surface of the balloon. The cutting assembly comprises a cutting blade and a rubber strip base. The cutting blade is provided with a protective layer on its surface. The cutting blade comprises a fixedly connected blade tip and a blade holder. The blade holder is fixed to the rubber strip base, and the rubber strip base is adhesively fixed to the surface of the balloon. Stress-enhanced zones are provided at both ends of the rubber strip base. The present invention avoids tissue damage by designing a cutting blade protective structure. Furthermore, the invention utilizes simple tooling to achieve efficient blade bonding, thereby improving bonding effectiveness and the fatigue resistance of the balloon.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and in particular to a cutting balloon catheter and a preparation method thereof. Background Art

[0002] Urethral stricture refers to an abnormal mechanical narrowing of the urethra lumen at any location, resulting in increased urethral resistance and impaired urination. With limited improvements in medical treatment, surgical procedures such as urethral dilation, endotomy, urethral reconstruction, and urethral stents are the primary treatments for urethral stricture. Urethral dilation, endotomy, and urethral reconstruction account for 80% of urethral stricture cases. Urethral dilation and endotomy are effective in the short term, but long-term results are not guaranteed, and urethral strictures have a high recurrence rate. Urethral reconstruction can be used to treat severe or recurrent urethral strictures. While it has a high success rate, it is more invasive and involves a larger incision, carrying the risk of postoperative infection, erectile dysfunction, urinary incontinence, or restenosis. Urethral stents are more suitable for patients who are unable or refuse surgery, but they can still pose complications such as infection, bleeding, and pain, require regular stent replacement, and have poor long-term efficacy.

[0003] The cutting balloon is an interventional treatment method developed based on traditional balloon intraluminal angioplasty. The cutting balloon mainly uses a balloon with a micro blade to expand and cut atherosclerotic plaques on the inner wall of the blood vessel. For narrow blood vessels that cannot be expanded by conventional balloons, the cutting balloon can usually achieve satisfactory results. Based on the mechanism of action of the cutting balloon, the cutting balloon can be used to treat physiological intraluminal strictures such as urethral strictures. However, due to the narrow and tortuous nature of the diseased urethra and the soft tissue surrounding the urethra, similar to the cutting balloon used to treat vascular stenosis, the cutting balloon faces challenges such as the blade easily damaging non-lesioned tissue, difficulty in passing, and the complex and poor firmness of the blade bonding process on the balloon surface. Summary of the Invention

[0004] The purpose of the present invention is to provide a cutting balloon catheter and a preparation method to solve the problems existing in the above-mentioned prior art. By designing a cutting blade protection structure, damage to tissue can be avoided, and the use of simple tooling can achieve efficient bonding of the blade, thereby improving the bonding effect and the fatigue resistance of the balloon.

[0005] To achieve the above object, the present invention provides the following solutions:

[0006] The present invention provides a cutting balloon catheter, comprising a balloon and a cutting assembly arranged on the outer surface of the balloon, the cutting assembly comprising a cutting blade and a rubber strip base, the surface of the cutting blade being provided with a protective layer, the cutting blade comprising a fixedly connected blade tip and a blade seat, the blade seat being fixed on the rubber strip base, the rubber strip base being adhesively fixed to the surface of the balloon, and stress reinforcement areas being provided at both ends of the rubber strip base.

[0007] In one embodiment, the protective layer completely covers the blade tip, and the longitudinal cross-sectional shape of the protective layer is regular or irregular or a combination of the two. The regular shape includes a circle, an arc and a teardrop shape, and the irregular shape includes a concave and convex curve shape.

[0008] In one embodiment, the rubber strip base completely covers the knife seat, and the shape of the stress enhancement area is regular or irregular or a combination of the two. The regular shape includes a circle, an arc and a teardrop shape, and the irregular shape includes a concave and convex curve shape.

[0009] In one embodiment, the cross-sectional shape of the blade tip is a regular shape, and the regular shape includes a triangle, a trapezoid, and a wedge; open grooves are provided at intervals along the length direction on the blade tip and the blade seat, and smooth transition zones are provided at the proximal and distal ends of the blade tip; the open grooves on the blade tip and the blade seat are distributed at equal intervals.

[0010] In one embodiment, the number of the balloons is set to at least one. When the number of the balloons is set to two or more, the balloons are arranged in sequence from the distal end to the proximal end. Among the two adjacent balloons, the diameter of the balloon on the distal side is less than or equal to the diameter of the balloon on the proximal side, and the length of the balloon on the distal side is less than or equal to the length of the balloon on the proximal side.

[0011] In one embodiment, the cutting blades on the surface of each balloon are arranged in the axial direction and are evenly distributed in the circumferential direction; in two adjacent balloons, the cutting blades on the balloon surface on the distal side and the cutting blades on the balloon surface on the proximal side are staggered in the circumferential direction.

[0012] In one embodiment, the surface of the balloon is sprayed with a drug coating, and the drug coating is a paclitaxel coating, a rapamycin coating, a paclitaxel derivative coating, or a rapamycin derivative coating.

[0013] In one embodiment, a balloon protective cover is provided on the outer side of the overall structure of the balloon and the cutting assembly; a protective partition is provided inside the balloon protective cover, and the protective partition is formed by protective ridges provided on the inner wall of the balloon protective cover, and a protective groove is provided on a side of the protective ridge close to the center, and the knife tip is placed in the protective groove, and the protective partition is used to protect the folded flap of the balloon.

[0014] The present invention provides a method for preparing the cutting balloon catheter described above, comprising preparing the cutting assembly and bonding the cutting assembly to the balloon;

[0015] The preparation of the cutting assembly includes:

[0016] The protective layer is formed on the surface of the cutting blade by dipping, brushing or spraying; the adhesive strip base is formed outside the blade holder by a bonding mold;

[0017] The bonding mold is provided with a forming groove, the depth of the forming groove is greater than the height of the knife seat, the width of the forming groove is greater than the thickness of the knife seat, the length of the forming groove is not less than the length of the cutting blade, stress diffusion bonding reinforcement areas are provided at both ends of the forming groove, the stress diffusion bonding reinforcement areas are arc-shaped grooves, the width of the arc-shaped groove is greater than the width of the forming groove, a knife tip placement groove is provided in the middle of the groove bottom of the forming groove, the depth of the knife tip placement groove is not less than the height of the knife tip, the width of the knife tip placement groove is equal to the thickness of the knife seat, and the length of the knife tip placement groove is not less than the length of the cutting blade;

[0018] Forming the rubber strip base includes: placing the blade tip in the blade tip placement groove, with the blade seat exposed in the forming groove; injecting glue into the forming groove, and after the glue solidifies, removing excess glue overflowing the forming groove, and removing the cutting blade from the bonding mold to obtain a fixed connection between the cutting blade and the rubber strip base;

[0019] The bonding of the cutting assembly to the balloon includes bonding the adhesive strip base to the outer surface of the balloon using glue.

[0020] The present invention provides a method for preparing the cutting balloon catheter described above, comprising:

[0021] An auxiliary tube is used to assist in bonding and fixing the cutting blade to the outer surface of the balloon. A bonding groove is provided on the surface of the auxiliary tube. The length of the bonding groove is greater than the length of the cutting blade, the width of the bonding groove is greater than the thickness of the blade holder, and the wall thickness of the auxiliary tube is greater than the height of the blade holder.

[0022] The bonding of the cutting blade includes: passing the balloon through the auxiliary tube, filling the balloon, and making the outer surface of the balloon fit the inner surface of the auxiliary tube; placing the blade holder into the bonding groove, making the blade holder perpendicular to and fit the outer surface of the balloon, and making the gaps between the two sides of the blade holder and the bonding groove equal; then filling the bonding groove with glue, and removing the auxiliary tube after the glue is cured;

[0023] The proximal end and the distal end of the bonding groove are both provided with a stress diffusion bonding reinforcement area; the stress diffusion bonding reinforcement area is an arc-shaped groove, and the width of the arc-shaped groove is greater than the width of the bonding groove.

[0024] Compared with the prior art, the present invention has achieved the following technical effects:

[0025] The cutting balloon catheter and preparation method provided by the present invention have the following characteristics: before the balloon is expanded, the protective layer isolates the cutting blade from the outside, reducing the damage of the cutting blade to the tissue; during the balloon interventional treatment of urethral stenosis, the balloon is slowly filled, and the cutting blade cuts the protective layer under the action of the balloon pressure, contacts the lesion site, and completes the stenosis cutting treatment; during the repeated filling, pressure relief and transportation of the balloon, the two ends of the cutting blade are the main stress concentration areas, and the stress comes from the resistance and friction caused by the physiological bending of the tissue along the axial direction of the balloon on the one hand, and from the interface stress between the balloon deformation and the blade base caused by the repeated filling and pressure relief of the balloon on the other hand; the present invention can obtain a rubber strip base with stress reinforcement areas at both ends through the bonding mold and the auxiliary tube, the bonding tooling of the cutting blade is simple, the bonding process is efficient, and the stress reinforcement areas at both ends of the rubber strip base are increased to diffuse stress and improve the bonding strength, thereby improving the bonding effect and the fatigue resistance of the balloon.

[0026] Furthermore, the present invention can restrain the balloon by providing a balloon protective cover, and prevent the cutting blade from damaging tissue cavities or blood vessels during transportation, thereby improving the ability of the cutting balloon to pass through narrow and tortuous lesions.

[0027] Furthermore, the blade tip and the blade holder of the present invention are both provided with open grooves at intervals along the length direction, which can improve the flexibility of the cutting blade and enhance the ability of the cutting balloon to pass through narrow and tortuous lesions. The proximal and distal ends of the blade tip are both provided with smooth transition areas, which can also enhance the ability of the cutting balloon to pass through narrow and tortuous lesions, thereby ensuring that the cutting blade can better pass through narrow and tortuous lesions.

[0028] Furthermore, for lesions with more severe stenosis, the present invention uses two or more balloons. Among the two adjacent balloons, the diameter of the balloon on the distal side is less than or equal to the diameter of the balloon on the proximal side, and the length of the balloon on the distal side is less than or equal to the length of the balloon on the proximal side. The balloon on the distal side can easily pass through the lesion first and perform the first expansion or pre-expansion, and then the balloon on the proximal side can be used to achieve further expansion, thereby realizing graded expansion, which is beneficial to improving the expansion effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0030] Figure 1 Schematic diagram of the structure of the cutting balloon catheter in Example 1 of the present invention;

[0031] Figure 2 1 is a side view of the cutting balloon catheter in Example 1 of the present invention;

[0032] Figure 3 This is a schematic structural diagram of a cutting blade in Embodiment 1 of the present invention;

[0033] Figure 4 A side view of a cutting blade in a first embodiment of the present invention;

[0034] Figure 5 This is a schematic structural diagram of a cutting assembly in Embodiment 1 of the present invention;

[0035] Figure 6 Schematic diagram of the structural relationship between the balloon and the balloon protective cover when the balloon is folded into three flaps (the cross-sectional profile of the outer protective layer of the cutting blade is circular) in Example 2 of the present invention;

[0036] Figure 7 Schematic diagram of the structural relationship between the balloon and the balloon protective cover when the balloon is folded into four wings (the cross-sectional profile of the outer protective layer of the cutting blade is circular) in Example 2 of the present invention;

[0037] Figure 8 Schematic diagram of the structural relationship between the balloon and the balloon protective cover when the balloon is folded into three flaps (the cross-sectional profile of the outer protective layer of the cutting blade is teardrop-shaped) in Example 2 of the present invention;

[0038] Figure 9 Schematic diagram of the structural relationship between the balloon and the balloon protective cover when the balloon is folded into four wings (the cross-sectional profile of the outer protective layer of the cutting blade is teardrop-shaped) in Example 2 of the present invention;

[0039] Figure 10Schematic diagram of the structural relationship between the balloon and the balloon protective cover when the balloon is folded into three wings (the blade tip is placed in the protective groove) in Example 3 of the present invention;

[0040] Figure 11 Schematic diagram of the structural relationship between the balloon and the balloon protective cover when the balloon is folded into four wings (the blade tip is placed in the protective groove) in Example 3 of the present invention;

[0041] Figure 12 This is a schematic structural diagram of a graded cutting balloon catheter in a fourth embodiment of the present invention;

[0042] Figure 13 Schematic side view of the staged cutting balloon catheter (with three cutting components) in Example 4 of the present invention;

[0043] Figure 14 Schematic side view of the staged cutting balloon catheter (with four cutting components) in Example 4 of the present invention;

[0044] Figure 15 This is a schematic diagram of the installation of the cutting blade and the bonding mold in the fifth embodiment of the present invention;

[0045] Figure 16 This is a schematic diagram of a cutting blade installed in a bonding mold in a fifth embodiment of the present invention;

[0046] Figure 17 This is a top view schematic diagram of the cutting blade installed in the bonding mold in the fifth embodiment of the present invention;

[0047] Figure 18 Schematic diagram of the structure of the auxiliary tube in Example 6 of the present invention;

[0048] Figure 19 Schematic diagram of the structure of the bonding groove and the stress diffusion bonding reinforcement area in the auxiliary tube in the sixth embodiment of the present invention;

[0049] Figure 20 This is a schematic diagram of using an auxiliary tube to assist the cutting blade in being bonded and fixed to the outer surface of the balloon in Example 6 of the present invention.

[0050] In the figure: 1-balloon, 101-wing, 2-cutting assembly, 3-cutting blade, 301-knife tip, 302-knife holder, 303-opening groove, 304-smooth transition area, 4-strip base, 5-bonding mold, 6-forming groove, 7-knife tip placement groove, 8-auxiliary tube, 9-bonding groove, 10-stress diffusion bonding reinforcement area, 11-balloon protective cover, 12-protection partition, 13-protection ridge, 131-protection groove, 14-protection layer. DETAILED DESCRIPTION

[0051] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0052] The purpose of the present invention is to provide a cutting balloon catheter and a preparation method to solve the problems existing in the prior art, improve the ability of the cutting balloon to pass through narrow and tortuous lesions, and avoid damage to tissues.

[0053] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0054] Example 1

[0055] like Figure 1-Figure 5 As shown, the present invention provides a cutting balloon catheter, including a balloon 1 and a cutting assembly 2 arranged on the outer surface of the balloon 1, the balloon 1 is a non-compliant balloon; the cutting assembly 2 includes a cutting blade 3 and a rubber strip base 4, the surface of the cutting blade 3 is provided with a protective layer 14, the cutting blade 3 includes a fixedly connected blade tip 301 and a blade seat 302, the blade seat 302 is fixed on the rubber strip base 4, and stress reinforcement areas are provided at both ends of the rubber strip base 4.

[0056] The protective layer 14 completely covers the blade tip 301 . The longitudinal cross-sectional shape of the protective layer 14 is regular or irregular or a combination of the two. The regular shape includes a circle, an arc, and a teardrop shape, and the irregular shape includes a concave-convex curve shape.

[0057] Before balloon 1 is expanded, the protective layer insulates cutting blade 3 from the outside world, minimizing tissue damage. During balloon interventional treatment of urethral strictures, balloon 1 is slowly inflated. The pressure from the balloon causes cutting blade 3 to cut through the protective layer, contact the lesion, and complete the stricture excision. After treatment, balloon 1 is slowly decompressed, and both the cutting blade 3 and the balloon are removed from the body.

[0058] The rubber strip base 4 completely covers the knife seat 302. The shape of the rubber strip base 4 is a long strip. The shapes of the stress reinforcement areas at both ends of the rubber strip base 4 are regular shapes or irregular shapes or a combination of the two. The regular shapes include circles, arcs and teardrop shapes, and the irregular shapes include concave and convex curves.

[0059] The cross-sectional shape of the blade tip 301 is a regular shape, which includes a triangle, a trapezoid and a wedge; the blade tip 301 and the blade seat 302 are both provided with open grooves 303 along the length direction, which can improve the flexibility of the cutting blade 3 and improve the ability of the cutting balloon to pass through stenotic and tortuous lesions. The proximal and distal ends of the blade tip 301 are both provided with smooth transition areas 304. The design of the smooth transition area 304 has a better streamlined structure, which can better adapt to the bending angle of the blood vessel, reduce the resistance when passing through the stenosis, reduce the risk of damage to the inner wall of the blood vessel, and improve the ability of the cutting balloon to pass through stenotic and tortuous lesions, thereby ensuring that the cutting blade 3 can better pass through the stenotic and tortuous lesions.

[0060] The blade holder 302 of the cutting blade 3 contacts the straight section of the balloon 1 surface. Three to four cutting blades 3 are evenly placed on the surface of each balloon 1 , and each cutting blade 3 is arranged vertically on the balloon 1 surface.

[0061] The protective layer 14 of the present invention is applied by dipping, brushing, or spraying. The solvent used is a material such as dimethylacetamide, dimethylformamide, toluene, dichloromethane, or tetrahydrofuran, and the solute can be a resin such as polyether block polyamide or polyurethane. During dipping, the solvent and solute are mixed as needed and dissolved at room temperature or under heating to form a dipping solution. The cutting blade 3 is dipped in the solution and then heated and dried to form a protective layer on the surface of the cutting blade 3.

[0062] The cutting blade 3 described in the present invention is made of a material with high strength and good toughness. Its length is determined according to the length of the lesion at the urethral stenosis, and ranges from about 5mm to 150mm. The angle of the blade tip 301 is 10° to 60°, the height of the blade tip 301 is 0.1-0.5mm, and the width of the blade seat 302 is 0.1-0.5mm. The blade material has high strength and good toughness, which can effectively cut the structure of the stenotic lesion while also ensuring the bending performance; the blade has a wide range of lengths, which can cover the needs of lesions of different lengths and cut the lesion as wide as possible on the urethral wall / blood vessel wall; the sharp angle design of the blade can make the blade apply more concentrated pressure when expanding, thereby achieving effective cutting of the lesion under a smaller expansion pressure; this design can ensure that the cutting blade 3 has a greater pressure in the radial direction, making it easier to cut the lesion.

[0063] In this embodiment, the opening slots 303 on the blade tip 301 are arranged alternately with the opening slots 303 on the blade holder 302. The opening slots 303 are semicircular in shape. In other embodiments, the opening slots 303 may also be semi-elliptical or other shapes.

[0064] In this embodiment, the opening slots 303 on the blade tip 301 are distributed at equal intervals, and the opening slots 303 on the blade seat 302 are distributed at equal intervals.

[0065] In the present invention, the surface of the balloon 1 can be sprayed with a drug coating, wherein the drug coating is a paclitaxel coating, a rapamycin coating, a paclitaxel derivative coating or a rapamycin derivative coating. After the cutting blade 3 cuts the lesion, the drug coating is slowly released into the lesion.

[0066] The balloon 1 of the present invention is made of materials such as Nylon, Pebax, or TPU. Its diameter ranges from 18F to 36F, and its effective length ranges from 10mm to 100mm, allowing it to cover most urethral stricture lesions. Its maximum expansion pressure is 8atm to 12atm. The balloon 1 exhibits excellent flexibility, enabling smooth delivery to the lesion site, and can achieve effective expansion at relatively low pressures.

[0067] The design of the balloon catheter includes an outer tube connected to the proximal end of the balloon 1 and an inner tube connected to the distal end of the balloon 1. The outer tube and the inner tube are made of materials such as Nylon or Pebax to meet the bending and pushing performance of the catheter.

[0068] The catheter hub of the balloon catheter is made of PC and is glued to the outer and inner tubes. The catheter hub has two Luer connectors: one for passing a guidewire and the other for connecting to the inflation device to inflate and relieve pressure on the balloon 1.

[0069] Example 2

[0070] like Figure 6-Figure 9 As shown, the present invention provides a cutting balloon catheter, which is different from the first embodiment in that a balloon protective cover 11 is provided on the outer side of the overall structure of the balloon 1 and the cutting assembly 2. The balloon protective cover 11 can restrain the balloon 1 and prevent the cutting blade 3 from damaging the tissue cavity or blood vessel during transportation. The protective layer 14 on the surface of the cutting blade 3 can be set to different shapes, such as Figure 6 and Figure 7 As shown in FIG, the cross-sectional profile of the protective layer 14 is circular, as shown in FIG. Figure 8 and Figure 9 As shown in FIG, the cross-sectional profile of the protective layer 14 is in the shape of a water drop.

[0071] Example 3

[0072] like Figure 10-11As shown, the present invention provides a cutting balloon catheter, wherein a protective partition 12 is provided in the balloon protective cover 11, and the protective partition 12 is formed by a protective rib 13 provided on the inner wall of the balloon protective cover 11. A protective groove 131 is provided on one side of the protective rib 13 close to the center, and the blade tip 301 is placed in the protective groove 131. The protective partition 12 is used to protect the wing 101 of the balloon 1 after folding. The protective groove 131 passes through the protective rib 13 in the axial direction, so that the balloon protective cover 11 can move axially relative to the balloon 1. The balloon protective cover 11 can be divided into a plurality of protective partitions 12 by the protective rib 13. As shown Figure 10 As shown in FIG, the protective rib 13 divides the balloon protective cover 11 into three protective partitions 12, and each protective partition 12 is provided with a wing 101. Figure 11 As shown in FIG, the protective ribs 13 divide the balloon protective cover 11 into four protective partitions 12 , and each protective partition 12 is correspondingly provided with a wing 101 .

[0073] Example 4

[0074] like Figure 12-14 As shown, the present invention provides a cutting balloon catheter having two balloons 1 arranged in sequence from distal to proximal. The diameter of the distal balloon 1 is smaller than the diameter of the proximal balloon 1, and the length of the distal balloon 1 is smaller than the length of the proximal balloon 1. Using a cutting balloon catheter with two balloons 1 for graded dilation can improve dilation effectiveness.

[0075] In this embodiment, the cutting blades 3 on the surface of each balloon 1 are arranged along the axial direction, and there are several cutting blades 3, such as three ( Figure 13 shown) or four ( Figure 14 in the two balloons 1, the cutting blade 3 on the surface of the balloon 1 on the distal side and the cutting blade 3 on the surface of the balloon 1 on the proximal side are staggered in the circumferential direction.

[0076] For lesion strictures that are difficult to dilate, such as vascular plaques and urethral lichenified plaque strictures, a cutting balloon catheter with two balloons 1 can be used for graded dilation, which is beneficial to improving the dilation effect.

[0077] The diameter of the distal balloon 1 is set to be smaller than that of the proximal balloon 1. The distal balloon 1 has a smaller outer diameter and is easy to pass through the stenotic plaque for primary expansion; and then further expansion is performed through the proximal balloon 1.

[0078] The length of the balloon 1 on the distal side is set to be smaller than that of the balloon 1 on the proximal side. The balloon 1 on the distal side is smaller in length, and the balloon can be more easily passed through a narrow gap by reducing its length.

[0079] The cutting blade 3 on the surface of the distal balloon 1 is staggered with the cutting blade 3 on the surface of the proximal balloon 1 in the circumferential direction, such as staggered by 30°-75° along the circumferential direction, to increase the position of the blade cutting in the circumferential direction and promote the expansion effect.

[0080] Example 5

[0081] like Figure 15-17 As shown, the present invention provides a method for preparing a cutting balloon catheter, including preparing a cutting component 2 and bonding the cutting component 2 to a balloon 1;

[0082] The preparation of the cutting assembly 2 includes:

[0083] Dip the cutting blade 3 in the dipping solution, then take it out, heat and dry it to form the protective layer on the surface; use the bonding mold 5 to form the rubber strip base 4 outside the blade holder 302;

[0084] A forming groove 6 is provided on the bonding mold 5, the depth of the forming groove 6 is greater than the height of the knife seat 302, the width of the forming groove 6 is greater than the thickness of the knife seat 302, the length of the forming groove 6 is not less than the length of the cutting blade 3, and stress diffusion bonding reinforcement areas 10 are provided at both ends of the forming groove 6. The stress diffusion bonding reinforcement areas 10 are arc-shaped grooves, the width of the arc-shaped groove is greater than the width of the forming groove 6, and a knife tip placement groove 7 is provided in the middle of the groove bottom of the forming groove 6. The depth of the knife tip placement groove 7 is not less than the height of the knife tip 301, the width of the knife tip placement groove 7 is equal to the thickness of the knife seat 302, and the length of the knife tip placement groove 7 is not less than the length of the cutting blade 3;

[0085] The molding rubber strip base 4 includes: placing the blade tip 301 in the blade tip placement groove 7, with the blade seat 302 exposed in the molding groove 6; injecting glue (intense glue, UV curing glue, or two-component glue) into the molding groove 6, and after the glue solidifies, removing the excess glue that overflows the molding groove 6, and removing the cutting blade 3 from the bonding mold 5 to obtain a fixed connection between the cutting blade 3 and the rubber strip base 4; the provision of the stress diffusion bonding enhancement area 10 creates stress enhancement areas at both ends of the rubber strip base 4, thereby increasing the bonding area of ​​the blade end;

[0086] The bonding of the cutting assembly 2 to the balloon 1 includes: bonding the adhesive strip base 4 to the outer surface of the balloon 1 using glue.

[0087] This manufacturing method ensures precise positioning of the cutting blade 3 and the adhesive strip base 4, reducing the error caused by directly bonding the cutting blade 3 to the balloon 1. Furthermore, because the thickness of the adhesive strip base 4 can be adjusted based on the size of the molding groove 6 of the bonding mold 5, the outer diameter of the folded cutting balloon can be effectively controlled.

[0088] Example 6

[0089] like Figures 18-20As shown, the present invention provides a method for preparing a cutting balloon catheter, comprising:

[0090] An auxiliary tube 8 is used to assist the cutting blade 3 in being bonded and fixed to the outer surface of the balloon 1. A bonding groove 9 is provided on the surface of the auxiliary tube 8. The length of the bonding groove 9 is greater than the length of the cutting blade 3, the width of the bonding groove 9 is greater than the thickness of the blade holder 302, and the wall thickness of the auxiliary tube 8 is greater than the height of the blade holder 302.

[0091] The bonding of the cutting blade 3 includes: folding the balloon 1 for pre-treatment, passing the folded balloon 1 through the auxiliary tube 8, and then filling the balloon 1. The balloon 1 needs to be filled to the RBP (rated bursting pressure) so that the outer surface of the balloon 1 fits with the inner surface of the auxiliary tube 8, and then the pressure is maintained; inserting the knife holder 302 into the bonding groove 9 so that the knife holder 302 is perpendicular and fits with the outer surface of the balloon 1, and the gap between the two sides of the knife holder 302 and the bonding groove 9 is equal, and then filling the bonding groove 9 with glue (instant glue or UV curing glue, etc.), and after the glue is cured, removing the auxiliary tube 8.

[0092] The auxiliary tube 8 can be made of latex or TPU, etc. The inner diameter of the auxiliary tube is approximately the outer diameter of the balloon 1 at RBP (assuming that the NP (nominal burst pressure) of the balloon is 4atm and the RBP is 6atm, the design size of the inner diameter of the auxiliary tube 8 is similar to the diameter of the balloon at RBP). The wall thickness of the auxiliary tube 8 is close to the thickness of the rubber strip, which is approximately 0.2~0.5mm. A laser is used to cut the shape of the rubber strip base 4 on the surface of the auxiliary tube 8. The shape of the rubber strip base 4 is rectangular or spiral, but not limited to the above shapes. In this embodiment, the rubber strip base 4 is a rectangular structure, and correspondingly, the bonding groove 9 is a rectangular groove.

[0093] When the auxiliary tube 8 needs to be removed, the auxiliary tube 8 can be torn open and removed; or the balloon 1 can be depressurized (without destroying the auxiliary tube 8), and the cutting blade 3 can be separated from the auxiliary tube 8. The auxiliary tube 8 can be reused, and the glue on the surface of the auxiliary tube 8 can be cleaned with alcohol after the auxiliary tube 8 is removed.

[0094] In this embodiment, stress diffusion bonding reinforcement areas 10 are provided at the proximal and distal ends of the bonding groove 9. The stress diffusion bonding reinforcement areas 10 are arc-shaped grooves. The width of the arc-shaped grooves is greater than the width of the bonding grooves 9. Stress reinforcement areas can be formed at both ends of the rubber strip base 4, thereby increasing the bonding area of ​​the blade end.

[0095] The cutting blade of this invention features a simple design and is easy to manufacture. Complex tooling and equipment are not required; bonding the cutting blade to the balloon can be accomplished using standard polymer tubing or injection molded parts. The addition of a transition zone to the cutting blade enhances the ability of the cutting balloon to pass through stenotic lesions. The use of an auxiliary tube aids in processing, with laser grooving ensuring precise positioning.

[0096] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only intended to help understand the method and core concept of the present invention. At the same time, those skilled in the art will find that the specific implementation methods and application scopes may vary based on the concept of the present invention. In summary, the contents of this specification should not be construed as limiting the present invention.

Claims

1. A cutting balloon catheter comprising a balloon and a cutting assembly disposed on the outer surface of the balloon, characterized in that: The cutting assembly includes a cutting blade and a rubber strip base. The surface of the cutting blade is provided with a protective layer. The cutting blade includes a fixedly connected blade tip and a blade seat. The blade seat is fixed to the rubber strip base. The rubber strip base is adhesively fixed to the surface of the balloon. Both ends of the rubber strip base are provided with stress reinforcement areas. A balloon protective cover is provided on the outer side of the overall structure of the balloon and the cutting assembly; a protective partition is provided inside the balloon protective cover, and the protective partition is formed by protective ridges provided on the inner wall of the balloon protective cover, and a protective groove is provided on a side of the protective ridge close to the center, and the protective groove passes through the protective ridge in the axial direction, and the knife tip is placed in the protective groove, and the protective partition is used to protect the folded flap of the balloon.

2. The cutting balloon catheter according to claim 1, characterized in that: The protective layer completely covers the blade tip, and the longitudinal cross-sectional shape of the protective layer is regular or irregular or a combination of the two. The regular shape includes a circle, an arc and a teardrop shape, and the irregular shape includes a concave-convex curve shape.

3. The cutting balloon catheter according to claim 1, characterized in that: The rubber strip base completely covers the knife seat, and the shape of the stress enhancement area is regular or irregular or a combination of the two. The regular shape includes a circle, an arc and a teardrop shape, and the irregular shape includes a concave and convex curve shape.

4. The cutting balloon catheter according to claim 1, characterized in that: The cross-sectional shape of the blade tip is a regular shape, which includes a triangle, a trapezoid and a wedge; open grooves are provided at intervals along the length direction on the blade tip and the blade seat, and smooth transition zones are provided at the proximal and distal ends of the blade tip; the open grooves on the blade tip and the blade seat are evenly spaced.

5. The cutting balloon catheter according to claim 1, characterized in that: The number of the balloons is set to at least one. When the number of the balloons is set to more than two, the balloons are arranged in sequence from the distal end to the proximal end. Among the two adjacent balloons, the diameter of the balloon on the distal side is less than or equal to the diameter of the balloon on the proximal side, and the length of the balloon on the distal side is less than or equal to the length of the balloon on the proximal side.

6. The cutting balloon catheter according to claim 5, characterized in that: The cutting blades on the surface of each balloon are arranged in the axial direction and are evenly distributed in the circumferential direction; in two adjacent balloons, the cutting blades on the balloon surface on the distal side and the cutting blades on the balloon surface on the proximal side are staggered in the circumferential direction.

7. The cutting balloon catheter according to claim 1, characterized in that: The surface of the balloon is sprayed with a drug coating, and the drug coating is a paclitaxel coating, a rapamycin coating, a paclitaxel derivative coating or a rapamycin derivative coating.

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