Balloon catheter

Abstract

The application relates to a balloon catheter, characterized in that the balloon catheter comprises a balloon, a catheter, a terminal tube, a developing ring, a catheter seat, a stress tube and a catheter sleeve, the catheter comprises an inner tube and an outer tube, the outer tube is sleeved outside the inner tube, the distal end of the inner tube is connected with the proximal end of the terminal tube, the distal end of the balloon is fixed on the outer surface of the terminal tube and / or the inner tube, the proximal end of the balloon is fixed on the outer surface of the distal end of the outer tube, the developing ring is arranged on the inner tube in the balloon, the stress tube is fixed on the distal end of the catheter seat, the proximal end of the inner tube is fixed inside the proximal end of the catheter seat through the stress tube and the catheter seat, the proximal end of the outer tube is fixed inside the distal end of the catheter seat through the stress tube and the catheter seat, and the catheter sleeve is sleeved outside the balloon. The balloon catheter can effectively treat arterial or venous stenosis and the like.

Description

Technical Field

[0001] This invention relates to the field of interventional medicine, specifically to a balloon catheter. Background Technology

[0002] Peripheral vascular disease encompasses diseases of the arterial and venous systems. Arterial disease is typically caused by deposits of fat and cholesterol (plaques) that build up on the walls of arteries, a process known as atherosclerosis. Atherosclerosis narrows the arteries, reducing blood flow. Atherosclerosis affects arteries throughout the body; if arteries supplying blood to the limbs become affected, it results in peripheral artery disease (PAD). Patients with PAD experience insufficient blood supply to the upper and lower limbs (most commonly the lower limbs), which can cause symptoms such as upper limb pain, leg muscle pain when walking, leg cramps, and difficulty walking. If PAD worsens, pain may occur even at rest or when lying down, potentially disrupting sleep. Simultaneously, plaque buildup in the arteries can also affect blood vessels in the heart and brain, potentially leading to stroke and heart attack. Venous diseases typically include venous compression syndromes, deep vein thrombosis, and more.

[0003] Therefore, there is an urgent need for medical devices applicable to the peripheral vascular system, including percutaneous endovascular angioplasty of the iliac artery and iliofemoral vein, as well as for the treatment of obstructive lesions of autologous or artificial arteriovenous dialysis fistulas. Summary of the Invention

[0004] To overcome the problems existing in the prior art, the present invention provides a balloon catheter.

[0005] In some embodiments of the present invention, the balloon catheter includes a balloon, a catheter, a distal tube, a catheter seat, and a stress tube. The catheter includes an inner tube and an outer tube. The outer tube is sleeved outside the inner tube. The distal end of the inner tube is connected to the proximal end of the distal tube. The distal end of the balloon is fixed to the outer surface of the distal tube and / or the inner tube. The proximal end of the balloon is fixed to the outer surface of the distal end of the outer tube. The stress tube is located at the distal end of the catheter seat. The proximal end of the inner tube passes through the stress tube and the catheter seat and is fixed inside the proximal end of the catheter seat. The proximal end of the outer tube passes through the stress tube and the catheter seat and is fixed inside the distal end of the catheter seat.

[0006] In some embodiments of the present invention, the outer diameter of the stress tube gradually decreases from the proximal end to the distal end, and the outer surface of the stress tube is provided with a plurality of alternating continuous recesses and discontinuous recesses. The continuous recesses include an annular recesses arranged around the circumference of the stress tube, and the discontinuous recesses include at least one circumferential recessed segment arranged along the circumference of the stress tube.

[0007] In some embodiments of the present invention, the balloon includes a first layer and a second layer, the second layer being disposed close to the inner tube, the first layer being disposed on the side of the second layer away from the inner tube, the first layer being made of nylon 12, the second layer being made of pebax, and the mass ratio of the first layer to the second layer being in the range of 6 / 4 to 8 / 2.

[0008] In some embodiments of the present invention, the balloon includes a first straight segment, a first transition segment, a second straight segment, a second transition segment, and an inflatable body portion. The first straight segment is fixed to the outer surface of the distal tube and / or the inner tube. The proximal end of the first straight segment is connected to the distal end of the first transition segment, and the proximal end of the first transition segment is connected to the distal end of the inflatable body portion. The second straight segment is fixed to the outer surface of the outer tube. The distal end of the second straight segment is connected to the proximal end of the second transition segment, and the distal end of the second transition segment is connected to the proximal end of the inflatable body portion.

[0009] In some embodiments of the present invention, the diameter of the first transition section gradually increases from the distal end to the proximal end, and the diameter of the second transition section gradually increases from the proximal end to the distal end. The balloon catheter further includes two radiopaque rings, one radiopaque ring being disposed on the inner tube at the position corresponding to the connection between the first transition section and the expansion body, and the other radiopaque ring being disposed on the inner tube at the position corresponding to the connection between the second transition section and the expansion body.

[0010] In some embodiments of the present invention, the inner surface of the outer tube and the outer surface of the inner tube together define an annular cavity, the inner cavity of the balloon is connected to the annular cavity, the proximal end of the catheter seat is provided with a guidewire port and an inflation port, the guidewire port is connected to the cavity of the inner tube, and the inflation port is connected to the annular cavity.

[0011] In some embodiments of the present invention, the ratio of the gap between the inner tube and the outer tube to the opening size of the filling port near the end of the conduit is 1:8.8-1:3.6, and the ratio of the opening size of the filling port near the end of the conduit to the opening size of the filling port away from the conduit is 1:2.5-1:1.81.

[0012] In some embodiments of the present invention, the distal end of the catheter seat protrudes distally to form a stepped structure. The catheter seat is provided with a first adhesive hole and a second adhesive hole. The first adhesive hole is disposed on the stepped structure and extends to the outer surface of the outer tube. The second adhesive hole is disposed on the catheter seat and extends to the outer surface of the inner tube. The second adhesive hole is located between the end of the filling port near the catheter and the end of the guidewire port near the catheter.

[0013] In some embodiments of the present invention, the ratio of the distance from the first adhesive hole to the distal end face of the stepped structure to the axial length of the stepped structure is 2 / 5 to 3 / 5, and the ratio of the distance from the second adhesive hole to the distal end face of the stepped structure to the axial length of the guide seat is 2 / 5 to 3 / 5.

[0014] In some embodiments of the present invention, the hardness of the end tube is less than that of the inner tube and the outer tube, and the ratio of the hardness of the end tube to the hardness of the inner tube or the outer tube is in the range of 1:1.1 to 1:1.6.

[0015] The solution to the technical problem of this invention is to provide a balloon catheter with the following advantages compared to existing technologies: The balloon catheter of this invention can effectively treat diseases of the peripheral vascular system, including percutaneous endovascular angioplasty of the iliac artery and iliofemoral vein, and obstructive lesions of autologous or artificial arteriovenous dialysis fistulas, etc. The balloon has characteristics such as high burst pressure and good retraction performance. The balloon diameter after compression is small, which can reduce damage to blood vessels and harm to the human body. The placement of the dispensing orifice also cleverly avoids blockage of the guidewire port, filling port, or annular lumen. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the three-dimensional structure of the balloon catheter provided in an embodiment of the present invention.

[0017] Figure 2 This is a schematic diagram of the balloon catheter fluoroscopic structure provided in an embodiment of the present invention.

[0018] Figure 3 This is a three-dimensional structural diagram of the stress tube of the balloon catheter provided in an embodiment of the present invention.

[0019] Figure 4 This is a schematic cross-sectional view of the balloon catheter in the circumferential direction provided in an embodiment of the present invention.

[0020] Figure 5 This is a schematic diagram of the balloon structure of the balloon catheter provided in an embodiment of the present invention.

[0021] Figure 6 This is a schematic diagram of the catheter seat structure of the balloon catheter provided in an embodiment of the present invention.

[0022] Figure 7 This is a schematic diagram of the cross-sectional structure of the balloon catheter provided in an embodiment of the present invention.

[0023] Figure Identification: 100, Balloon catheter; 1, Balloon; 2, Catheter; 3, Terminal tube; 4, Contrast ring; 5, Catheter seat; 6, Stress tube; 7, Catheter sleeve; 21, Inner tube; 22, Outer tube; 11, First layer; 12, Second layer; 13, First straight segment; 14, First transition segment; 15, Second straight segment; 16, Second transition segment; 17, Inflatable main body; 131, First mating part; 151, Second mating part; 211, Annular cavity; 18, Inner cavity; 51, Guidewire orifice; 52, Filling orifice; 53, Stepped structure; 531, Engaging part; 54, First adhesive hole; 55, Second adhesive hole; 61, Continuous recess; 62, Intermittent recess; 611, Annular recess; 621, Circumferential recess. Detailed Implementation

[0024] Exemplary embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the invention and to fully convey the scope of the invention to those skilled in the art.

[0025] It should be understood that the terminology used herein is for the purpose of describing particular exemplary embodiments only and is not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms “a,” “an,” and “described” as used herein may also include the plural forms. The terms “comprising,” “including,” “containing,” and “having” are inclusive and therefore indicate the presence of the stated features, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components, and / or combinations thereof. The method steps, processes, and operations described herein are not construed as requiring them to be performed in a particular order described or illustrated unless the order of performance is explicitly indicated. It should also be understood that additional or alternative steps may be used.

[0026] Although terms such as first, second, third, etc., may be used in this document to describe multiple elements, components, regions, layers, and / or segments, these elements, components, regions, layers, and / or segments should not be limited by these terms. These terms may be used only to distinguish one element, component, region, layer, or segment from another. Unless the context clearly indicates otherwise, terms such as "first," "second," and other numerical terms used herein do not imply order or sequence. Therefore, the first element, component, region, layer, or segment discussed below may be referred to as the second element, component, region, layer, or segment without departing from the teachings of the exemplary embodiments.

[0027] For ease of description, spatial relative terms may be used in the text to describe the relationship of one element or feature relative to another element or feature, as shown in the figure. These relative terms include, for example, "inside," "outside," "middle," "outer," "below," "below," "above," "over," etc. Such spatial relative terms are intended to include different orientations of the device in use or operation, other than those depicted in the figure. For example, if the device in the figure is flipped, an element described as "below other elements or features" or "below other elements or features" would subsequently be oriented as "above other elements or features" or "above other elements or features." Therefore, the example term "below" can include both upper and lower orientations. The device may be otherwise oriented (rotated 90 degrees or in other directions), and the spatial relative descriptors used in the text will be interpreted accordingly.

[0028] To more clearly describe the structure of this application, the terms "proximal" and "distal" are used herein as conventional terms in the field of interventional medicine. Specifically, "distal" refers to the end furthest from the operator during the surgical procedure, "proximal" refers to the end closest to the operator during the surgical procedure, "axial" refers to its length direction, and "radial" refers to the direction perpendicular to the "axial".

[0029] Please see Figure 1 and Figure 2This invention provides a balloon catheter 100, which is particularly suitable for percutaneous endovascular angioplasty of the peripheral vascular system, including the iliac artery and iliofemoral vein, and for the treatment of obstructive lesions of autologous or artificial arteriovenous dialysis fistulas. It is also suitable for post-dilation of stents and covered stents in peripheral vessels. The balloon catheter 100 includes a balloon 1, a catheter 2, a distal tube 3, a contrast ring 4, a catheter seat 5, a stress tube 6, and a catheter sheath 7. The catheter 2 includes an inner tube 21 and an outer tube 22, with the outer tube 22 sleeved over the inner tube 21, and the inner tube 21 and outer tube 22 being coaxially arranged. The distal end of the inner tube 21 is connected to the proximal end of the distal tube 3, and the distal tube 3 is coaxially arranged with the inner tube 21 and communicates with the lumen of the inner tube 21. The distal end of the balloon 1 is fixed to the outer surface of the distal tube 3 and / or the inner tube 21. In a specific embodiment of the present invention, part of the distal end of the balloon 1 is fixed to the outer surface of the distal tube 3, and part is fixed to the outer surface of the inner tube 21. The proximal end of the balloon 1 is fixed to the outer surface of the distal end of the outer tube 22. The radiopaque ring 4 is disposed on the inner tube 21 inside the balloon 1. The stress tube 6 is fixed to the distal end of the catheter seat 5. The proximal end of the inner tube 21 passes through the stress tube 6 and the catheter seat 5 and is fixed inside the proximal end of the catheter seat 5. The proximal end of the outer tube 22 passes through the stress tube 6 and the catheter seat 5 and is fixed inside the distal end of the catheter seat 5. The catheter sleeve 7 is fitted over the balloon 1.

[0030] It is understood that fixing part of the distal end of the balloon 1 to the outer surface of the distal tube 3 and part to the outer surface of the inner tube 21 makes the connection between the inner tube 21 and the distal tube 3 more secure, preventing the distal tube 3 from becoming disconnected from the inner tube 21. Furthermore, in this specific embodiment of the invention, the connection between the inner tube 21 and the distal tube 3 is achieved by hot air welding. Fixing part of the distal end of the balloon 1 to the outer surface of the distal tube 3 and part to the outer surface of the inner tube 21 also conceals the welding marks between the inner tube 21 and the distal tube 3, ensuring the overall aesthetic appearance of the balloon catheter 100. The imaging ring 4 is fixed to the inner tube 21 inside the balloon 1, thereby facilitating in vivo observation and positioning of the balloon 1. The stress tube 6 has a frustum structure, and its outer diameter gradually decreases from the proximal end to the distal end. The portion of the conduit 2 near the conduit seat 5 is prone to bending, which can lead to damage. The stress tube 6 provides some fixation to this portion, preventing large-angle bending and thus avoiding damage. Furthermore, the balloon 1 is provided with a wing (not shown in the figure), which is existing technology and will not be described further. The conduit sleeve 7 is worn on the balloon 1 when the balloon conduit 100 is not in use. When the balloon conduit 100 needs to be used, the conduit sleeve 7 needs to be removed. The conduit sleeve 7 protects the balloon 1 and, when the balloon conduit 100 is not in use, maintains the shape of the wing, preventing it from warping. A hydrophilic coating is provided on the outer surface of the terminal tube 3, the outer surface of the balloon 1, and the outer surface of the outer tube to ensure the smooth passage of the balloon catheter 100 through the body.

[0031] Furthermore, the working principle of the balloon catheter 100 is as follows: Information such as the location, diameter, and length of the stenosis is confirmed through angiography, and then a balloon catheter 100 of the appropriate specification is selected. A sheath is then inserted to establish a channel, and a guidewire is inserted to establish a track. The balloon catheter 100 then travels externally along this channel and track until its distal end passes through the stenotic segment (aligning the balloon 1 with the stenotic segment). Pressure is then applied to the balloon catheter 100 using a pressure dilator, causing the balloon 1 to inflate. The inflated balloon 1 compresses the stenotic segment, causing atherosclerotic material and arterial plaque to be deformed and adhere to the inner wall of the blood vessel. Further inflation of the balloon 1 causes appropriate tearing of the smooth muscle of the blood vessel wall, further expanding the blood vessel and its lumen. After maintaining this position for a period of time (approximately tens of seconds to several minutes), the pressure on the balloon 1 is released, and it is withdrawn along the guidewire and channel. At this point, the lumen of the stenotic segment of the blood vessel has expanded, restoring good blood supply.

[0032] Please see Figure 3The outer surface of the stress tube 6 is provided with a plurality of alternating continuous recesses 61 and discontinuous recesses 62. Each continuous recess 61 includes an annular recess 611 arranged around the circumference of the stress tube, and each discontinuous recess 62 includes at least one circumferential recess 621 arranged along the circumference of the stress tube 6. Specifically, the annular recess 611 is a closed ring-shaped recess formed by indentation into the outer surface of the stress tube 6, and the circumferential recess 621 is a small segment of recess formed by indentation into the outer surface of the stress tube 6. The alternation of continuous recesses 61 and discontinuous recesses 62 can be understood as follows: one continuous recess 61 is connected to one discontinuous recess 62, this discontinuous recess 62 is connected to another continuous recess 61, another continuous recess 61 is connected to another discontinuous recess 62, and so on, alternating between continuous recesses 61 and discontinuous recesses 62. Alternating between continuous recesses 61 and discontinuous recesses 62 provides good support and strength for the stress tube 6, resulting in more uniform stress distribution, preventing cracking, and improving fatigue performance. It also ensures good flexibility to accommodate deformation of the conduit 2. This balance between support and flexibility prevents the stress tube from becoming too stiff or too soft, maintaining its flexibility and stress relief effect without causing the tube wall to be too thin and resulting in sleeve damage. Furthermore, in a specific embodiment, each discontinuous recess 62 includes two circumferential recessed segments 621, which are symmetrically arranged, with staggered arrangements between adjacent discontinuous recesses 62.

[0033] Please continue reading. Figure 3 The width d1 of each annular recess 611 is consistent with the width d2 of each circumferential recess segment 621, making the overall size of the stress tube 6 more uniform, the stress on the stress tube 6 more even, and the bending of the stress tube 6 smoother, avoiding the concentration of stress on a certain point when bending the stress tube 6. At the same time, to further ensure the flexibility and smoothness of bending of the stress tube 6, the ratio of the axial length of the stress tube 6 to the width d1 or d2 is in the range of 24:1 to 28:1. In a specific embodiment of the present invention, the ratio of the axial length of the stress tube 6 to the width d1 or d2 is specifically 26:1.

[0034] Please see Figure 4The balloon 1 comprises a first layer 11 and a second layer 12. The second layer 12 is disposed close to the inner tube 21, and the first layer 11 is disposed on the side of the second layer 12 away from the inner tube 21. To ensure that the balloon 1 can achieve a high burst pressure, the material of the first layer 11 is nylon 12, and the material of the second layer 12 is Pebax. The mass ratio of the first layer 11 to the second layer 12 is 6 / 4 to 8 / 2. In a specific embodiment of the present invention, the mass ratio of the first layer 11 to the second layer 12 is specifically 7 / 3. The double-layer configuration of the balloon 1 and the mass ratio of the first layer 11 to the second layer 12 being set to 7 / 3 enable the balloon 1 to have a high burst pressure, thereby ensuring the safety of the balloon 1. At the same time, it ensures the retraction performance of the balloon 1, resulting in less obstruction and smoother retraction during the retraction process.

[0035] In other specific embodiments of the present invention, the balloon 1 may also be a single-layer structure, wherein the balloon 1 is extruded from a mixture of nylon 12 and pebax in a mass ratio of 7 / 3. The mass ratio of nylon 12 to pebax can be adaptively set according to the actual burst pressure requirements and the requirements for recoil performance, such as a specific mass ratio of nylon 12 to pebax of 8 / 2 or 6 / 4, etc.

[0036] Please see Figure 2 and Figure 5 When the balloon 1 is not inflated, the balloon 1 includes a first straight segment 13, a first transition segment 14, a second straight segment 15, a second transition segment 16, and an inflatable main body 17. The first straight segment 13 is fixed to the outer surface of the terminal tube 3 and / or the inner tube 21, and the first straight segment 13 acts as a connecting part, connecting to the outer surface of the terminal tube 3 and / or the inner tube 21. In a specific embodiment of the present invention, a portion of the first straight segment 13 is connected to the outer surface of the terminal tube 3, and the remaining portion of the first straight segment 13 is connected to the outer surface of the inner tube 21. The proximal end of the first straight segment 13 is connected to the distal end of the first transition segment 14, and the proximal end of the first transition segment 14 is connected to the distal end of the inflatable main body 17. The second straight segment 15 is fixed to the outer surface of the outer tube 22, and the second straight segment 15 acts as a connecting part, connecting to the outer surface of the outer tube 22. The distal end of the second straight segment 15 is connected to the proximal end of the second transition segment 16, and the distal end of the second transition segment 16 is connected to the proximal end of the inflatable main body 17. The diameter of the first transition segment 14 gradually increases from the distal end to the proximal end, and the diameter of the second transition segment 16 gradually increases from the proximal end to the distal end.

[0037] It is understood that, in specific embodiments of the present invention, the first straight segment 13, the first transition segment 14, the second straight segment 15, the second transition segment 16, and the expansion body 17 are integrally formed. The length of the expansion body 17 is the effective length of the balloon 1, that is, when the balloon 1 is inflated, the expansion body 17 is the main inflated part, and the remaining parts will not be inflated or will only be partially inflated. The length of the expansion body 17 is 20mm-120mm. The expansion body 17 refers to the part whose diameter after inflation is 5 to 7 times that of its uninflated state. For example, when the balloon catheter 100 is adapted to a 7F delivery sheath, the diameter of the uninflated balloon 1 is 2.31mm, while the diameter of the inflated balloon 1 reaches 12mm. The number of imaging rings 4 is two. One imaging ring 4 is located on the inner tube 21 at the position where the first transition section 14 connects to the expansion body 17, and the other imaging ring 4 is located on the inner tube 21 at the position where the second transition section 16 connects to the expansion body 17. The imaging rings 4 can be used to determine the position of the balloon 1 in the body, and at the same time, the imaging rings 4 can determine the position of the expansion body 17, thereby confirming the effective length of the balloon 1 in the body, so that the effective length of the balloon 1 can be more accurately applied to the lesion site. In other specific embodiments of the present invention, the first straight segment 13, the first transition section 14, the second straight segment 15, the second transition section 16, and the expansion body 17 can also be manufactured separately.

[0038] For further information, please refer to [link / reference]. Figure 2 and Figure 5In a specific embodiment of the present invention, since the dimensions of the first straight segment 13 and the second straight segment 15 are larger than those of the end tube 3, the inner tube 21, and the outer tube 22, if the first straight segment 13 is directly connected to the end tube 3 and the inner tube 21, or the second straight segment 15 is directly connected to the outer tube 22, then redundant portions of the first straight segment 13 and the second straight segment 15 cannot be directly connected to the end tube 3, the inner tube 21, and the outer tube 22. These redundant portions will accumulate on the end tube 3, the inner tube 21, and the outer tube 22 before being heat-welded, thereby increasing the outer diameter of the two ends of the balloon 1. The minimum size of the balloon 1 after folding and compression depends on the dimensions of the two ends of the balloon 1. If the dimensions of the two ends of the balloon 1 are large, then the size of the balloon 1 after folding and compression will also be large. Therefore, in order to reduce the size of the two ends of the balloon 1, so that the size of the balloon 1 after compression is smaller, thereby reducing damage to blood vessels and harm to the human body, the first straight segment 13 and the second straight segment 15 are cut and then directly connected to the terminal tube 3 and the inner tube 21. This avoids redundant parts in the first straight segment 13 and the second straight segment 15 that cannot be directly connected to the terminal tube 3, the inner tube 21 and the outer tube 22, thereby minimizing the size of the balloon 1 after compression.

[0039] Specifically, the distal end of the first straight segment 13 and the proximal end of the second straight segment 15 are uniformly cut, such that the distal end of the first straight segment 13 includes at least two spaced-apart first mating portions 131, and the proximal end of the second straight segment 15 includes at least two spaced-apart second mating portions 151. Each first mating portion 131 and each second mating portion 151 has the same size. It can be understood that, in this specific embodiment of the invention, the first straight segment 13 and the second straight segment 15 are cut in both horizontal and vertical directions, resulting in four first mating portions 131 and four second mating portions 151. By connecting the four first mating parts 131 to the end tube 3 and the inner tube 21, and the four second mating parts 151 to the outer tube 22, the contact area between the first straight segment 13 and the second straight segment 15 and the end tube 3, the inner tube 21, and the outer tube 22 is reduced. This ensures that all the first mating parts 131 can be connected to the end tube 3 and the inner tube 21, and all the second mating parts 151 can be connected to the outer tube 22, avoiding redundant parts in the first straight segment 13 and the second straight segment 15. Simultaneously, uniformly trimming the distal end of the first straight segment 13 and the proximal end of the second straight segment 15 ensures that each first mating part 131 and each second mating part 151 has the same size, thus avoiding redundant parts caused by a single large size of one first mating part 131 or one second mating part 151.

[0040] Please see Figure 2 The inner surface of the outer tube 22 and the outer surface of the inner tube 21 together define an annular cavity 211, and the inner cavity 18 of the balloon 1 communicates with the annular cavity 211. The proximal end of the catheter seat 5 is provided with a guidewire port 51 and an inflation port 52. The guidewire port 51 communicates with the cavity of the inner tube 21, and the inflation port 52 communicates with the annular cavity 211. Specifically, the guidewire port 51 is used to insert a guidewire. The guidewire enters through the guidewire port 51, then enters the cavity of the inner tube 21, passes through the inner tube 21, enters the cavity of the distal tube 3, and finally exits from the distal end of the distal tube 3. The inflation port 52 is used to allow inflation fluid to enter the annular cavity 211. After passing through the annular cavity 211, the inflation fluid enters the inner cavity 18 of the balloon 1, causing the balloon 1 to inflate.

[0041] Further, please refer to Figure 1 , Figure 2 , Figure 6 and Figure 7The distal end of the catheter seat 5 protrudes to form a stepped structure 53. A locking portion 531 protrudes from the outer surface of the stepped structure 53. The proximal end of the stress tube 6 is sleeved on the stepped structure 53 and fixed to it via the locking portion 531. The catheter seat 5 is provided with a first adhesive hole 54 and a second adhesive hole 55. The first adhesive hole 54 is located on the stepped structure 53. The ratio of the distance S1 from the first adhesive hole 54 to the distal end face of the stepped structure 53 to the axial length of the stepped structure 53 is 2 / 5 to 3 / 5, and the first adhesive hole 54 extends to the outer surface of the outer tube 22. The second adhesive hole 55 is located on the catheter seat 5. The ratio of the distance S2 from the second adhesive hole 55 to the distal end face of the stepped structure 53 to the axial length of the catheter seat is 2 / 5 to 3 / 5, and the second adhesive hole 55 extends to the outer surface of the inner tube 21.

[0042] It is understood that glue can be dripped into the first glue-applying hole 54 to fix the outer tube 22 relative to the conduit seat 5. Glue can be dripped into the second glue-applying hole 55 to fix the inner tube 21 relative to the conduit seat 5. Simultaneously, the first glue-applying hole 54 is positioned at a distance S1 from the distal end face of the stepped structure 53, ensuring a certain distance between the first glue-applying hole 54 and the distal end of the stepped structure 53, as well as a certain distance from the proximal end of the outer tube 22 and the filling port 52. This prevents glue from seeping into the annular cavity 211 and blocking it, and also prevents glue from seeping into and blocking the filling port 52, and also prevents glue from overflowing from the distal end of the conduit seat 5. The second adhesive hole 55 is positioned at a distance S2 from the distal end face of the stepped structure 53, and the second adhesive hole 55 is located between the end D1 of the filling port 52 near the conduit 2 and the end D2 of the guide wire port 51 near the conduit 2. This ensures that the second adhesive hole 55 is at a certain distance from the proximal end of the outer tube 22, and also at a certain distance from the guide wire port 51 and the filling port 52. This prevents adhesive from penetrating into the guide wire port 51, the filling port 52, and the annular cavity 211, thereby preventing adhesive from blocking the guide wire port 51, the filling port 52, or the annular cavity 211.

[0043] Please continue reading. Figure 1 , Figure 2 and Figure 7The balloon 1 provided by this invention features rapid pressure relief. Specifically, the ratio of the gap between the inner tube 21 and the outer tube 22 to the opening size L1 of the filling port 52 near the conduit 2 is 1:8.8–1:3.6, and the ratio of the opening size L1 of the filling port 52 near the conduit 2 to the opening size L2 of the filling port 52 away from the conduit is 1:2.5–1:1.81. In a specific embodiment of this invention, the gap between the inner tube 21 and the outer tube 22 is set at 0.25 mm–0.5 mm, the opening size L1 of the filling port 52 near the conduit 2 is 1.8 mm–2.2 mm, and the opening size L2 of the filling port 52 away from the conduit is 4 mm–4.5 mm. By setting these dimensions, the fluid flow rate inside the balloon 1 is faster, thereby reducing the pressure relief time of the balloon 1. For example, when the effective length of the balloon 1 is 60 mm, the inflated diameter of the balloon 1 is 18 mm, the gap between the inner tube 21 and the outer tube 22 is set at 0.42 mm, the opening size L1 of the inflation port 52 near the catheter 2 is 2.06 mm, and the opening size L2 of the inflation port 52 away from the catheter is 4.29 mm, the depressurization time of the balloon 1 is 20 seconds.

[0044] Please continue reading. Figure 2 The hardness of the distal tube 3 is less than that of the inner tube 21 and the outer tube 22. The ratio of the hardness of the distal tube to that of the inner or outer tube is between 1:1.1 and 1:1.6. Specifically, the hardness of the distal tube 3 is 50D-60D, and the hardness of the inner tube 21 and the outer tube 22 is 67D-77D. In a specific embodiment of the present invention, the hardness of the distal tube 3 is 55D, and the hardness of the inner tube 21 and the outer tube 22 is 72D. This is because reducing the hardness of the distal end of the balloon catheter 100 improves the smoothness of the balloon catheter 100 when it enters the human body, thus avoiding damage to human tissues, blood vessels, etc. when the balloon catheter 100 enters the human body. The outer tube 22 and the inner tube 21 have high hardness because when the balloon 1 is inflated, the filling liquid will exert pressure on the inner tube 21 and the outer tube 22. In order to prevent the inner tube 21 and the outer tube 22 from deforming, the inner tube 21 and the outer tube 22 have high hardness.

[0045] Compared with existing technologies, the balloon catheter of the present invention has the following advantages: The balloon catheter of the present invention can effectively treat diseases of the peripheral vascular system, including percutaneous endovascular angioplasty of the iliac artery and iliofemoral vein, and obstructive lesions of autologous or artificial arteriovenous dialysis fistulas, etc. The balloon has the characteristics of high burst pressure and good retraction performance. The balloon diameter after compression is small, which can reduce damage to blood vessels and harm to the human body. The placement of the dispensing hole can also cleverly avoid the occlusion of the guidewire port, filling port, or annular lumen.

[0046] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A balloon catheter, characterized in that: The balloon catheter includes a balloon, a catheter, a distal tube, a catheter seat, and a stress tube. The catheter includes an inner tube and an outer tube, with the outer tube sleeved over the inner tube. The distal end of the inner tube is connected to the proximal end of the distal tube. The distal end of the balloon is fixed to the outer surface of the distal tube and / or the inner tube. The proximal end of the balloon is fixed to the outer surface of the distal end of the outer tube. The stress tube is located at the distal end of the catheter seat. The proximal end of the inner tube passes through the stress tube and the catheter seat and is fixed inside the proximal end of the catheter seat. The proximal end of the outer tube passes through the stress tube and the catheter seat and is fixed... The outer tube is positioned inside the distal end of the catheter hub; the inner surface of the outer tube and the outer surface of the inner tube together define an annular cavity, the inner cavity of the balloon is connected to the annular cavity, and an inflation port is provided at the proximal end of the catheter hub, which is connected to the annular cavity; the ratio of the gap between the inner tube and the outer tube to the opening size of the inflation port near the catheter is 1:8.8-1:3.6, and the ratio of the opening size of the inflation port near the catheter to the opening size of the end of the inflation port away from the catheter is 1:2.5-1:1.

81.

2. The balloon catheter as described in claim 1, characterized in that: The outer diameter of the stress tube gradually decreases from the proximal end to the distal end. The outer surface of the stress tube is provided with a plurality of alternating continuous recesses and discontinuous recesses. The continuous recesses include an annular recesses arranged around the circumference of the stress tube, and the discontinuous recesses include at least one circumferential recessed segment arranged along the circumference of the stress tube.

3. The balloon catheter as described in claim 1, characterized in that: The balloon includes a first layer and a second layer. The second layer is disposed close to the inner tube, and the first layer is disposed on the side of the second layer away from the inner tube. The material of the first layer is nylon 12, and the material of the second layer is pebax. The mass ratio of the first layer to the second layer is in the range of 6 / 4 to 8 / 2.

4. The balloon catheter as described in claim 1, characterized in that: The balloon includes a first straight segment, a first transition segment, a second straight segment, a second transition segment, and an inflatable body. The first straight segment is fixed to the outer surface of the distal tube and / or the inner tube. The proximal end of the first straight segment is connected to the distal end of the first transition segment, and the proximal end of the first transition segment is connected to the distal end of the inflatable body. The second straight segment is fixed to the outer surface of the outer tube. The distal end of the second straight segment is connected to the proximal end of the second transition segment, and the distal end of the second transition segment is connected to the proximal end of the inflatable body.

5. The balloon catheter as described in claim 4, characterized in that: The diameter of the first transition section gradually increases from the distal end to the proximal end, and the diameter of the second transition section gradually increases from the proximal end to the distal end. The balloon catheter also includes two radiopaque rings. One radiopaque ring is disposed on the inner tube at the position corresponding to the connection between the first transition section and the expansion body, and the other radiopaque ring is disposed on the inner tube at the position corresponding to the connection between the second transition section and the expansion body.

6. The balloon catheter as described in claim 1, characterized in that: The proximal end of the catheter seat is provided with a guidewire port, which is connected to the cavity of the inner tube.

7. The balloon catheter as described in claim 6, characterized in that: The distal end of the catheter seat protrudes to form a stepped structure. The catheter seat is provided with a first adhesive hole and a second adhesive hole. The first adhesive hole is located on the stepped structure and extends to the outer surface of the outer tube. The second adhesive hole is located on the catheter seat and extends to the outer surface of the inner tube. The second adhesive hole is located between the end of the filling port near the catheter and the end of the guidewire port near the catheter.

8. The balloon catheter as described in claim 7, characterized in that: The ratio of the distance from the first adhesive hole to the distal end face of the stepped structure to the axial length of the stepped structure is 2 / 5-3 / 5, and the ratio of the distance from the second adhesive hole to the distal end face of the stepped structure to the axial length of the guide seat is 2 / 5-3 / 5.

9. The balloon catheter as described in claim 1, characterized in that: The hardness of the end tube is less than that of the inner tube and the outer tube, and the ratio of the hardness of the end tube to that of the inner tube or the outer tube is in the range of 1:1.1-1:1.6.

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