Balloon-type catheter and preparation method thereof

Abstract

The invention relates to the field of medical instruments, in particular to a balloon type catheter and a manufacturing method thereof.The balloon type catheter comprises a catheter body, a balloon arranged at the far end of the catheter body and an injection assembly arranged at the near end of the catheter body, the catheter body comprises an inner-layer tube and an outer-layer tube arranged outside the inner-layer tube in a sleeving mode, and the inner-layer tube and the outer-layer tube are assembled and formed after being machined in a split mode; a supporting component is arranged on the outer surface of the inner-layer tube, the outer side face of the supporting component is in contact with the inner wall of the outer-layer tube, so that a continuous annular medium channel is formed between the inner-layer tube and the outer-layer tube, and the annular medium channel is communicated with the inner cavity of the balloon; the inner-layer tube and the outer-layer tube are respectively machined and assembled and formed in an assembling mode, the supporting strips are arranged on the outer side face of the inner-layer tube, an annular medium channel can be formed, the circumferential space of the catheter is fully utilized, and the liquid filling and sucking efficiency of the balloon is greatly improved.

Description

TECHNICAL FIELD

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

[0002] The balloon dilatation catheter is an interventional surgical instrument through the human body cavity, which has the advantages of small trauma and fast recovery, and is widely used in the fields of vascular surgery, neurology, cardiology, cardiothoracic surgery, respiratory medicine, and gastroenterology, especially including aortic endovascular therapy, peripheral artery and vein interventional therapy, coronary artery interventional therapy, valve interventional therapy, and other structural heart disease therapy, etc., and has the functions of dilating stenosis blood vessels, expanding the caliber of blood vessels and valves, and compressing hemangioma. In terms of structure, the balloon dilatation catheter is mainly composed of a balloon, a catheter, a catheter seat, etc., wherein the balloon is the inflated part at the distal end of the catheter, which expands the stent or valve by filling fluid, and the catheter is a tubular instrument for guiding the balloon to the treatment site. The balloon dilatation catheter is classified into balloon dilatation catheters (including directional catheters, balloon catheters, vascular stent catheters, and atrial resection catheters) and hook-end interventional catheters.

[0003] The catheter with balloon type catheter often adopts fixed integrated structure design, which is formed by integrated die of single material, and the multiple lumen tube is formed by one cavity throughout the catheter with balloon type, to form a guide cavity for the guide wire or other medical devices, and the other cavity is formed by one or more side holes in the proximal end region and the distal end region of the catheter from the side wall, to form a balloon filling medium channel. The design has disadvantages, including: 1) low efficiency of balloon filling and discharging: due to the existing design and manufacturing process level, the medium channel can only use the cavity (defined as: balloon medium cavity) in the multiple lumen tube except the guide cavity, and cannot fully utilize the transverse space between the inner surface of the guide cavity and the entire outer surface of the catheter. The more the number of cavities set for the catheter lumen, the more difficult the manufacturing process and the higher the cost, and the larger the cavity space required for the balloon medium cavity, the greater the probability of breaking the wall between the balloon medium cavity and the outer surface of the catheter, and the lower the production yield. This is a difficult contradiction for the efficiency of balloon filling and discharging (including: liquid filling / discharging process), experimental data shows that the existing technology catheter balloon medium cavity area ratio is less than 40% of the total transverse space area, resulting in low efficiency of balloon filling and discharging (physiological saline inflation time ≥8 seconds), which is difficult to meet the clinical demand of rapid inflation of the balloon during the operation; 2) high cost of medium channel forming and manufacturing, and unstable quality: the existing technology is usually formed by integrated continuous extrusion of extrusion molding equipment, and the continuous and uninterrupted pipe drawing during the extrusion process is prone to twisting of the cavities around the central axis of the catheter, resulting in poor coaxiality of the medium channel and unstable quality. The single catheter after cutting the length is artificially opened from the side wall of the proximal end region and the distal end region, and the hole opening process involves direct alignment of the balloon medium cavity on the outer surface under naked eye, which requires strict alignment process, and the hole opening process requires high opening size and range, but the existing technology adopts artificial processing, which is difficult to control due to many human factors or variables, resulting in high manufacturing cost and unstable quality; 3) it is difficult or impossible to comply with the design concept and development trend of thin-walled catheter: for the manufacturing of multiple lumen tube, the design and size control of integrated die is crucial, and efficient balloon filling and discharging speed means that the integrated die design is shackled, and the size control requirement is more stringent, which is particularly prominent in the development trend of thin-walled catheter, such as catheter wall thickness controlled within 0.3mm, and the existing technology is difficult to meet.

[0004] For example, patent CN202010485164.3 discloses a balloon dilatation catheter, which comprises a balloon, the balloon has one perfusion cavity and at least one fluid channel, the fluid channel extends through the balloon in the axial direction, and the fluid channel is not in communication with the perfusion cavity. In this patent scheme, the perfusion cavity only occupies part of the area of the catheter, and the circumferential area cannot be fully utilized, and due to the process of one-piece extrusion molding, it is difficult to ensure the consistency of the catheter in the axial direction after the length of the catheter is lengthened, and the catheter is prone to twist at a certain angle, causing the perfusion cavity to be twisted circumferentially, further reducing the liquid absorption efficiency.

[0005] Therefore, it is necessary to design a new type of balloon catheter, which can fully utilize the circumferential space in the catheter, improve the balloon inflation and deflation efficiency, meet the clinical needs, and at the same time, comply with the development trend of thin-walled catheters, so that it is possible to expand the application of sheath tubes with functions of balloon inflation and deflation and passage establishment. SUMMARY

[0006] In view of the above and other more ideas, the present application is proposed.

[0007] One of the purposes of the present application is to overcome the shortcomings of the prior art, especially the problem that the balloon catheter in the prior art cannot fully utilize the circumferential space inside the catheter, resulting in low balloon inflation and deflation efficiency, and to provide a balloon catheter.

[0008] The technical solution adopted to solve the technical problems of the present application is to provide a balloon catheter, which comprises a catheter, a balloon arranged at the distal end of the catheter, and an injection assembly arranged at the proximal end of the catheter, the catheter comprises an inner tube and an outer tube sleeved outside the inner tube, the outer surface of the inner tube is provided with a support member, the outer side surface of the support member is in contact with the inner wall of the outer tube, so that an annular medium channel is formed between the inner tube and the outer tube, and the annular medium channel is in communication with the inner cavity of the balloon.

[0009] In a preferred embodiment, the support member is a plurality of support protrusions regularly distributed on the inner tube, and the support protrusions are fixedly connected with the inner tube.

[0010] In a more preferred embodiment, all the support protrusions are distributed in a dot matrix pattern in the axial and circumferential directions of the inner tube.

[0011] In a more preferred embodiment, the dot matrix pattern is at least 2x2.

[0012] In a preferred embodiment, the support member is at least two support strips extending in the axial direction of the inner tube, and the support strips are fixedly connected with the inner tube.

[0013] In a more preferred embodiment, the support strips are provided in 3-20 strips, and at least 2 support strips can abut against the inner wall of the outer tube.

[0014] As a further improvement of the present application, the inner tube and the outer tube are separately extruded and assembled to form.

[0015] As a further improvement of the present application, since the inner tube and the outer tube are separately extruded and assembled to form, the inner tube and the outer tube can be made of different polymer materials; and the corresponding materials can be selected according to the performance requirements of the inner tube and the outer tube, for example: the inner tube is made of a material with strong shape retention, including PTFE, PA, PC, PEEK, PI, so that the accommodation space provided by the lumen is maximized in the curved state or under the radial extrusion stress of the tissue, facilitating the smoothness of the inner cavity space through the medical device such as a guide wire, and the upward compatibility of the inner cavity through the medical device size; the outer tube is made of a material with better flexibility under the premise of ensuring the sufficient inflation and deflation quality of the balloon, including Pebax, PU, silicone, PE, PA with low hardness (e.g. ≤80HD), so that: ① the outer tube and the inner tube can be fully attached, minimizing the cross-sectional area of the outer tube, facilitating the thinning of the entire tube wall; ② the tube has good compliance in the axial direction, can fully comply with the anatomical access form, and avoid the risk of folding failure of the prior art under small bending radius, so it is particularly suitable for irregular anatomical access, such as special patient groups with calcified and narrowed blood vessel lumen, tortuous or even twisted and angled access, etc.; ③ the radial direction has better compliance, facilitating the outer tube to deform to the limit under the action of the radial extrusion force of the access tissue, and the resistance feeling of the entire tube during the process of entering or withdrawing from the tissue is better, thus minimizing the damage risk and pain feeling of the skin or muscle tissue touched during the access process.

[0016] As a further improvement of the present application, the distal end of the inner tube extends beyond the distal end of the outer tube, so that the distal end portion of the catheter has a stepped diameter-reducing structure, wherein the proximal end of the balloon is sealingly connected to the distal end of the outer tube, and the distal end of the balloon is sealingly connected to the distal end of the inner tube.

[0017] As a further improvement of the present application, the proximal end and the distal end of the balloon are sealingly connected to the outer surface of the outer tube, and at least one medium through hole is provided at the distal end region of the outer tube at the balloon lumen, and the medium through hole is used to communicate the medium channel and the balloon lumen.

[0018] As a further improvement of the present application, the medium through hole is at least two, and the medium through hole is located in the gap region between the adjacent support strips in the circumferential direction, and the axial projection of the medium through hole completely falls into the gap region of the adjacent support strips.

[0019] As a further improvement of the present application, all the medium through holes are distributed in axial direction of the outer tube with staggered arrangement, and the axial projection of any two medium through holes has no overlap in the range of 360° in the circumferential direction.

[0020] As a further improvement of the present application, the distal end of the inner tube is flush with the distal end of the outer tube in the radial direction.

[0021] As a further improvement of the present application, the proximal end of the outer tube is sealingly connected with the distal end of the injection assembly, and the proximal end of the inner tube extends to the proximal end of the injection assembly, and the injection channel on the injection assembly is in communication with the medium channel.

[0022] As a further improvement of the present application, the recess on the support strip forms a continuous annular medium channel in the circumferential direction, and the recess on the support strip does not block the flow of the medium in the channel.

[0023] As a further improvement of the present application, the recess on the support strip is arranged in the proximal end region of the inner tube, and the recess is located in the balloon lumen space.

[0024] As a further improvement of the present application, the recess on the support strip is arranged at a position corresponding to the injection channel, or the recess on the support strip is arranged at a position near the injection channel; when the medium enters the medium channel through the injection channel, the medium can fill the entire annular medium channel through the recess.

[0025] As a further improvement of the present application, the balloon is a compliant balloon; or the balloon is a semi-compliant balloon.

[0026] As a further improvement of the present application, a new preparation method of a balloon catheter mainly includes the following steps: S1. The inner tube and the outer tube are respectively processed by extrusion or other methods, and the length is cut according to clinical requirements, and the distal end of the outer tube is perforated; S2. The outer tube is sleeved outside the inner tube, so that the support member is in contact with the inner wall of the outer tube; (the distal end of the outer tube is perforated to communicate with the annular medium channel, and the precise positioning of the perforation can also be performed in this step); S3. The distal end of the inner tube and the distal end region of the outer tube are sealingly and fixedly connected; S4. The two ends of the balloon are sealingly connected with the distal end of the outer tube, and the perforation position is located in the balloon, so that the balloon lumen is in communication with the annular medium channel; S5. The proximal end of the outer tube is sealingly and fixedly connected with the distal end of the injection assembly, and the proximal end of the inner tube is sealingly and fixedly connected with the proximal end of the injection assembly, so that the injection channel on the injection assembly is in fluid communication through the medium channel, the perforation, and the balloon cavity in sequence.

[0027] In the prior art, due to the fact that the balloon expansion catheter is formed by an integrated extrusion process, the medium channel can only be in a local area of the circumference of the catheter, and the circumferential space of the catheter cannot be fully utilized, resulting in low balloon inflation and deflation efficiency. When the length of the catheter is increased, due to the disadvantages of the integrated extrusion process, the catheter will be twisted in the circumferential direction, affecting the coaxiality of the catheter, and further reducing the balloon inflation and deflation efficiency. According to one concept of the present application, the inner tube and the outer tube are processed separately, and a support member is provided on the outer side of the inner tube, such as at least two support strips, which contact the inner wall of the outer tube to form an annular medium channel. Since the inner tube and the outer tube can be processed separately and assembled by assembly process, the coaxiality of the catheter is ensured, and the coaxiality of the medium channel is also ensured to the greatest extent. The injection channel of the injection assembly can be directly connected to the medium channel, so that the space between the outer tube and the inner tube is fully utilized, the inflation and deflation efficiency is greatly improved, and the medium such as gas or liquid can quickly flow in the medium channel and reach or leave the inner cavity of the balloon at a very fast speed, improving the inflation or retraction efficiency of the balloon.

[0028] In the prior art, before the balloon is connected to the catheter, the distal end of the catheter is located in the inner cavity of the balloon, and the catheter needs to be perforated to connect the medium channel. However, the medium channel in the prior art is located in a certain area of the circumferential position of the catheter, so it is necessary to find the position of the perforation when perforating, which undoubtedly increases the process difficulty, resulting in high cost of medium channel forming and processing, and unstable quality. According to one concept of the present application, since the inner tube and the outer tube can be processed separately and formed by assembly, the distal ends of the inner tube and the outer tube have a stepped reduced diameter structure, so one end of the balloon can be connected to the outer tube and the other end can be connected to the inner tube, eliminating the perforation process step, simplifying the preparation process of the balloon catheter, and improving the quality stability of the balloon inflation and deflation.

[0029] In the prior art, due to the one-piece extrusion process, the proximal end of the catheter needs to be drilled to communicate with the injection port after connecting the injection assembly, and the existing medium channel is located in a local area of the catheter in the circumferential direction. Therefore, when assembling the injection assembly, the injection port needs to be aligned with the medium channel. Due to the small caliber of the injection port, the worker has great difficulty in assembling and the assembly efficiency is low. According to one concept of the present application, since the inner tube and the outer tube are separately processed and assembled in a sleeved manner, for example, the distal end of the injection assembly is connected with the proximal end of the outer tube, and the inner tube extends to the proximal end inside the injection assembly. In this way, the injection channel can directly communicate with the medium channel, and the worker does not need to consider the position of the medium channel during assembly. This not only simplifies the preparation process, but also improves the efficiency of liquid filling.

[0030] In the prior art, due to the one-piece extrusion process, the catheter can only be made of a single material, and the performance of the catheter is limited by the single material. According to one concept of the present application, since the inner tube and the outer tube are separately processed and assembled in a sleeved manner, the corresponding material and process design can be carried out according to the various clinical needs of the catheter during use, especially according to the performance requirements of the inner tube and the outer tube. For example: the inner tube is made of a special material with strong shape retention, so that the inner tube provides the maximum accommodation space in the lumen under the conditions of bending or being subjected to radial extrusion stress, thereby ensuring the smoothness of the inner cavity space through medical devices such as guide wires and catheters; and the outer tube can be made of a material with better flexibility, so as to reduce the resistance when the catheter enters the blood vessel and reduce the damage to the blood vessel tissue and the pain. At the same time, the combination design of the inner tube and the outer tube makes the wall thickness of the entire balloon catheter thin, and the overall wall thickness can be reduced from 0.3-0.8mm in the prior art to 0.1-0.3mm. Therefore, the present application conforms to the development trend of thin-walled catheters, and makes it possible to expand the application of sheath tubes with functions such as balloon inflation and passage establishment.

[0031] The embodiments of the present application can achieve other advantageous technical effects not listed one by one, which are described in the following and can be expected and understood by those skilled in the art after reading the present application. BRIEF DESCRIPTION OF DRAWINGS

[0032] The above-mentioned features and advantages of the embodiments, as well as other features and advantages of the embodiments and the ways to achieve them will be more apparent and can be better understood by referring to the following description in conjunction with the accompanying drawings, in which: Figure 1 The catheter structure of the novel balloon dilatation catheter of the present application is shown in the figure.

[0033] Figure 2Fig. 1 is a schematic diagram of the overall structure of a novel balloon catheter according to the present application.

[0034] Figure 3 、 Figure 4 and Figure 5 Fig. 2 is a schematic diagram of the inner tube structure of a novel balloon catheter according to the present application.

[0035] Figure 6 Fig. 3 is a schematic diagram of the catheter cross-sectional structure of a novel balloon catheter according to the present application.

[0036] The features referred to by the numerals in the drawings are as follows: 1 - catheter, 11 - inner tube, 12 - outer tube, 13 - support member, 131 - groove, 132 - support bar, 133 - support bump, 14 - annular medium passage, 15 - medium through hole, 2 - injection assembly, 21 - injection passage, 3 - balloon. DETAILED DESCRIPTION

[0037] The details of one or more embodiments of the application are set forth in the description below. Other features, objects, and advantages of the application will be apparent from the description and drawings, and from the claims.

[0038] It should be understood that the illustrated and described embodiments are not limited in application to the details of construction and arrangement of parts illustrated in the following description or illustrated in the drawings. The illustrated embodiments can be one of many embodiments and can be practiced or carried out in various ways. Examples are provided by way of explanation of the disclosed embodiments but are not intended to be limiting. Indeed, it will be apparent to those skilled in the art that various modifications and variations can be made in the embodiments described and suggested herein without departing from the scope or spirit of the application. For instance, features illustrated or described as part of one embodiment, can be used with another embodiment to yield still a further embodiment. Thus, it is intended that the present application cover modifications and variations of this application provided they come within the scope of the appended claims and their equivalents.

[0039] Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of "including," "comprising" or "having" and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items.

[0040] The application will be described in greater detail with reference to the various embodiments and examples of several aspects of the application.

[0041] One of the aims of the embodiments described below is to solve the above-mentioned drawbacks, and other problems.

[0042] Embodiment I: A balloon catheter, such asFigure 1 and Figure 2 As shown in FIG. 1, the injection assembly 2 is arranged at the proximal end of the catheter 1, and the balloon 3 is arranged at the distal end of the catheter 1. The catheter 1 comprises an inner tube 11 and an outer tube 12 sleeved on the outer tube 11. The outer surface of the inner tube 11 is provided with a support member 13. The outer side surface of the support member 13 is in contact with the inner wall of the outer tube 12, so that an annular medium channel 15 is formed between the inner tube 11 and the outer tube 12, and the annular medium channel 15 is in communication with the inner cavity of the balloon 3.

[0043] In this embodiment, as shown in FIG. 1, the support member 13 is at least two support strips 1322 extending axially along the inner tube 11. The support strips 1322 are fixedly connected with the inner tube 11. Figure 3 and Figure 4 In this embodiment, the support strips 1322 are provided with 3-20 support strips, and at least two support strips 1322 can abut against the inner wall of the outer tube 12.

[0044] In this embodiment, the inner tube 11 and the outer tube 12 are independently processed and assembled to form the outer tube 12 sleeved on the inner tube 11.

[0045] In this embodiment, since the inner tube 11 and the outer tube 12 are respectively processed and assembled, the inner tube 11 and the outer tube 12 can be made of different polymer materials. According to the performance requirements of the inner tube 11 and the outer tube 12, the corresponding materials can be selected, for example, the inner tube 11 is made of PTFE with strong shape retention, and the outer tube 12 is made of Pebax with better flexibility under the premise of ensuring sufficient inflation of the balloon.

[0046] In this embodiment, the material of the balloon can be PU.

[0047] In this embodiment, the proximal end and the distal end of the balloon are respectively sealed and connected to the outer surface of the outer tube 12. At least two medium through holes 15 are arranged at the distal end of the outer tube 12 in the inner cavity of the balloon. The medium through holes 15 are used for communication between the medium channel and the inner cavity of the balloon.

[0048] In this embodiment, as shown in FIG. 1, the medium through holes 15 are located in the gap region between the adjacent support strips 132 in the circumferential direction, and the axial projection of the medium through holes 15 completely falls into the gap region of the adjacent support strips 132.

[0049] In this embodiment, as shown in FIG. 1, the medium through holes 15 are located in the gap region between the adjacent support strips 132 in the circumferential direction, and the axial projection of the medium through holes 15 completely falls into the gap region of the adjacent support strips 132. Figure 5

[0050] ​In the embodiment, all the medium through holes 15 are distributed in axial direction of the outer tube 12 with a staggered arrangement, and the axial projection of any two medium through holes 15 does not overlap in the circumferential direction of 360°.

[0051] In the embodiment, the distal end of the inner tube 11 is flush with the distal end of the outer tube 12 in the radial direction.

[0052] In the embodiment, the injection assembly 2 is provided with an injection channel 21, the proximal end of the outer tube 12 is sealingly connected to the distal end of the injection assembly 2, the proximal end of the inner tube 11 extends to the proximal end of the injection assembly 2, and the injection channel 21 communicates with the medium channel.

[0053] In the embodiment, the support strip 132 is provided with a groove 131, which forms a continuous annular medium channel 14 in the circumferential direction, and the groove 131 allows the support strip 132 to not block the flow of the medium in the channel.

[0054] In the embodiment, the balloon 3 is a compliant balloon.

[0055] In the embodiment, the preparation method of the balloon catheter mainly includes the following steps: S1. The inner tube 11 and the outer tube 12 are respectively processed by extrusion and the like, and the length is cut according to clinical requirements, and the distal end of the outer tube 12 is perforated; S2. The outer tube 12 is sleeved outside the inner tube 11, so that the support member 13 is in contact with the inner wall of the outer tube 12; (the distal end of the outer tube 12 is perforated to communicate with the annular medium channel 15, and the perforation can also be accurately positioned at this step); S3. The distal end of the inner tube 11 and the distal end of the outer tube 12 are sealingly and fixedly connected; S4. The two ends of the balloon 3 are sealingly connected to the distal end of the outer tube 12, and the perforation position is located in the balloon 3, so that the inner cavity of the balloon 3 communicates with the annular medium channel 15; S5. The proximal end of the outer tube 12 is sealingly and fixedly connected to the distal end of the injection assembly 2, and the proximal end of the inner tube 11 is sealingly and fixedly connected to the proximal end of the injection assembly 2, so that the injection channel 21 provided on the injection assembly 2 is in fluid communication with the medium channel 15, the perforation, and the cavity of the balloon 3 in sequence. Embodiment

[0056] Embodiment two is basically the same as embodiment one, except that the connection mode of the balloon and the catheter in this embodiment.

[0057] A new type of balloon dilatation catheter, comprising a catheter 1, a balloon 3 arranged at the distal end of the catheter 1, and an injection assembly 2 arranged at the proximal end of the catheter 1, wherein the catheter comprises an inner tube 11 and an outer tube 12 sleeved outside the inner tube 11, the outer surface of the inner tube 11 is provided with at least two support strips 132 extending in the axial direction, the outer side surface of the support strip 132 is in contact with the inner wall of the outer tube 12, so that an annular medium passage 14 is formed between the inner tube 11 and the outer tube 12, and the annular medium passage 14 is in communication with the balloon lumen.

[0058] In the embodiment, the distal end of the inner tube 11 extends out of the distal end of the outer tube 12, so that the distal end portion of the catheter is in a stepped diameter-reduced structure, wherein the proximal end of the balloon is sealingly connected with the distal end of the outer tube 12, and the distal end of the balloon is sealingly connected with the distal end of the inner tube 11.

[0059] In the embodiment, the injection assembly 2 is provided with an injection channel 21, the proximal end of the outer tube 12 is sealingly connected with the distal end portion of the injection assembly 2, the proximal end of the inner tube 11 extends to the proximal end portion of the injection assembly 2, and the injection channel 21 is in communication with the medium passage.

[0060] In the embodiment, one end of the balloon is connected with the outer tube 12, the other end of the balloon is connected with the inner tube 11, and the connection between the proximal end of the catheter and the injection assembly 2 also does not need to be perforated, so that the preparation process of the balloon dilatation catheter can be completed only by simple assembly and bonding, which greatly simplifies the process steps, reduces the process difficulty, and also improves the liquid absorption efficiency of the balloon and eliminates the coaxial problem of the catheter.

[0061] In this regard, the relevant structure and concept of the second embodiment are similar to those of the first embodiment, and thus will not be described here again. Embodiment

[0062] The third embodiment is basically the same as the first embodiment, except that the support member in the third embodiment is designed in a support protrusion type structure instead of a strip structure.

[0063] A new type of balloon dilatation catheter, comprising a catheter 1, a balloon 3 arranged at the distal end of the catheter 1, and an injection assembly 2 arranged at the proximal end of the catheter 1, wherein the catheter comprises an inner tube 11 and an outer tube 12 sleeved outside the inner tube 11, the outer surface of the inner tube 11 is provided with at least two support strips 132 extending in the axial direction, the outer side surface of the support strip 132 is in contact with the inner wall of the outer tube 12, so that an annular medium passage 14 is formed between the inner tube 11 and the outer tube 12, and the annular medium passage 14 is in communication with the balloon lumen.

[0064] In the embodiment, the distal end of the inner tube 11 extends out of the distal end of the outer tube 12, so that the distal end portion of the catheter is in a stepped diameter-reduced structure, wherein the proximal end of the balloon is sealingly connected with the distal end of the outer tube 12, and the distal end of the balloon is sealingly connected with the distal end of the inner tube 11. Figure 4As shown, the support member 13 is a plurality of support protrusions 133 regularly distributed on the inner layer tube 11, and the support protrusions 133 are fixedly connected with the inner layer tube 11.

[0065] In this embodiment, all the support protrusions 133 are distributed in a dot matrix pattern in the axial and circumferential directions of the inner layer tube 11.

[0066] In this embodiment, the dot matrix distribution of the support protrusions 133 is at least 2x2, and in consideration of the stability of the support member 13 in actual use, three columns of support protrusions 133 are usually provided, and one protrusion is provided at intervals of 5 cm in each column of support protrusions 133, as shown. Figure 5

[0067] In this regard, the relevant structure and concept of Embodiment Three are similar to those of Embodiment One, and thus will not be described again here.

[0068] The foregoing description of above-described embodiments of the present application is presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the application to the precise configurations, structures, and / or steps described, as obvious modifications and variations are possible in light of the above teachings. The scope of the application is defined by the claims appended hereto.​

Claims

1. A balloon catheter comprising a catheter, a balloon disposed at a distal end of the catheter, and an injection assembly disposed at a proximal end of the catheter, characterized by: The catheter comprises an inner tube and an outer tube sleeved outside the inner tube, the inner tube and the outer tube are separately processed and then assembled to form a shape, wherein an outer surface of the inner tube is provided with a support member, an outer side surface of the support member is in contact with an inner wall of the outer tube, a continuous annular medium channel is formed between the inner tube and the outer tube, and the annular medium channel is in communication with an inner cavity of a balloon.

2. The balloon catheter of claim 1, wherein: The support member is a plurality of regularly distributed support protrusions on the inner tube, the support protrusions are fixedly connected with the inner tube, and all the support protrusions are distributed in a dot matrix mode in the axial and circumferential directions of the inner tube.

3. The balloon catheter of claim 1, wherein: The support member is at least two support strips extending in the axial direction of the inner tube, and the support strips are fixedly connected with the inner tube.

4. A novel balloon dilatation catheter as claimed in claim 3, wherein: The support strips are provided with grooves, and the grooves make the annular medium channel form a continuous annular medium channel in the circumferential direction.

5. The balloon catheter of claim 1, wherein: A distal end of the inner tube extends out of a distal end of the outer tube, so that a distal end part of the catheter has a stepped diameter-reducing structure, wherein a proximal end of the balloon is sealingly connected with the distal end of the outer tube, and a distal end of the balloon is sealingly connected with the distal end of the inner tube.

6. The balloon catheter of claim 1, wherein: The proximal end and the distal end of the balloon are sealingly connected to an outer surface of the outer tube, at least two medium through holes are arranged at the distal end of the outer tube at the inner cavity of the balloon, the medium through holes are used for communicating the medium channel with the inner cavity of the balloon, an injection channel is arranged on the injection assembly, a proximal end of the outer tube is sealingly connected with a distal end part of the injection assembly, a proximal end of the inner tube extends to a proximal end part of the injection assembly, and the injection channel is in communication with the medium channel.

7. A balloon catheter according to claims 3 and 6, characterized in that: The medium through holes are located in the gap regions between adjacent support strips in the circumferential direction, and the axial projection of the medium through hole completely falls into the gap region of the adjacent support strip.

8. The balloon catheter of claims 2, 3 and 6, wherein: All the medium through holes are distributed in a staggered manner in the axial direction of the outer tube, and the axial projections of any two medium through holes do not overlap in the circumferential direction of 360°.

9. The balloon catheter of claim 1, wherein: The inner tube and the outer tube are made of different polymer materials, and the balloon is a compliant or semi-compliant balloon.

10. A novel method of preparing a balloon-tipped catheter according to any one of claims 1-9, characterized by: The method comprises the following steps: S1. separately processing the inner tube and the outer tube by extrusion or the like, cutting to length according to clinical requirements, and opening a hole at a distal end part of the outer tube; S2. sleeving the outer tube outside the inner tube, so that the support member is in contact with the inner wall of the outer tube; S3. sealingly and fixedly connecting the distal end of the inner tube and the distal end region of the outer tube; S4. sealingly connecting the two ends of the balloon with the distal end part of the outer tube, and arranging the opening position in the balloon, so that the inner cavity of the balloon is in communication with the annular medium channel; S5. sealingly and fixedly connecting the proximal end of the outer tube with the distal end part of the injection assembly, and sealingly and fixedly connecting the proximal end of the inner tube with the proximal end part of the injection assembly, so that an injection channel arranged on the injection assembly is in fluid communication with the medium channel, the opening, and the balloon cavity in sequence.

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