WO2022033193A1

WO2022033193A1 - Balloon dilatation catheter

Info

Publication number: WO2022033193A1
Application number: PCT/CN2021/102216
Authority: WO
Inventors: 周宇; 段志邦; 史增佐; 杨爱丽
Original assignee: 上海鸿脉医疗科技有限公司
Priority date: 2020-08-12
Filing date: 2021-06-24
Publication date: 2022-02-17
Also published as: CN114073809A; AR123213A1

Abstract

A balloon dilatation catheter, comprising a push tube (100), an inner tube (200), and a balloon (300); the inner tube (200) is provided at a distal end of the push tube (100), the balloon (300) is sleeved on an outer surface of the inner tube (200), and the push tube (100) is formed by blending and extruding polylaurolactam and polyether block polyamide. The push tube (100) of the balloon dilatation catheter has both reliable support and good flexibility, and can pass through tortuous blood vessels, calcification and long-segment occluded blood vessels, improving usage performance.

Description

A balloon dilatation catheter

technical field

The invention relates to the technical field of medical devices, in particular to a balloon dilatation catheter.

Background technique

Since the first successful percutaneous transluminal coronary angioplasty (PTCA) in 1977 became the beginning of interventional therapy, interventional therapy has developed rapidly in the past four decades, especially in the last decade. The application of interventional therapy has developed from the initial coronary artery to almost all blood vessels in the body. Interventional therapy has the advantages of less bleeding, less trauma, less complications, quick postoperative recovery, safety and reliability, and greatly reduces the pain suffered by patients. Balloon dilation is a common interventional procedure used to dilate narrowed blood vessels.

In recent years, with the intensification of the aging population in my country, the incidence of lower extremity ischemia caused by arteriosclerosis and occlusion of the lower extremity in elderly patients is increasing. The lesions of lower extremity ischemia are characterized by calcification and lengthening of the lesions. When using balloon dilatation for treatment, due to the poor pushing performance and low compressive strength of the existing balloon dilatation catheter, it is difficult for the balloon dilatation catheter to pass through calcified lesions and long occluded blood vessels, and the related operation cannot be completed. treat.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a balloon dilatation catheter, which has good pushability and can smoothly pass through calcified lesions and long occluded blood vessels.

In order to achieve the above purpose, the present invention provides a balloon dilatation catheter, comprising a push tube, an inner tube and a balloon, the inner tube is arranged at the distal end of the push tube, and the balloon is sleeved inside the inner tube. The outer surface of the pipe; wherein, the push pipe is formed by blending and extruding polylauractam and polyether block polyamide.

Optionally, the mass ratio of the polylaurolactam to the polyether block polyamide is (1.5-9):1.

Optionally, the balloon is a high pressure balloon.

Optionally, the balloon dilatation catheter further comprises a hydrophilic coating, the hydrophilic coating covers the outer surface of the balloon and the outer surface of the distal end of the push tube; and/or, the balloon The balloon dilation catheter further includes a tapered tip, which is disposed at the distal end of the inner tube and protrudes from the distal end of the balloon; the hydrophilic coating covers the outer surface of the tapered tip surface, the outer surface of the balloon, and the distal outer surface of the pusher tube.

Optionally, in the axial direction of the balloon dilatation catheter, the length of the hydrophilic coating is 300mm-500mm.

Optionally, the push tube includes a filling cavity and a guide wire cavity that are arranged in parallel along its axial direction and are isolated from each other; the cross section of the filling cavity is crescent-shaped, and the distal end of the filling cavity is connected to the balloon. communication; the cross section of the guide wire lumen is circular, and the distal end of the guide wire lumen communicates with the inner tube.

Optionally, the distal lumen wall of the guide wire lumen and the proximal pipe wall of the inner tube are integrally formed by hot pressing.

Optionally, the balloon dilation catheter further includes a connecting piece, the connecting piece is disposed at the proximal end of the pushing tube and includes a first joint and a second joint; the first joint is communicated with the filling cavity, The second connector communicates with the guide wire lumen.

Optionally, the distance from the proximal end of the filling cavity to the proximal end of the balloon is less than the distance from the proximal end of the guide wire cavity to the proximal end of the balloon; A perfusion hole is provided on the proximal cavity wall, the perfusion hole communicates with the first joint, and the proximal end of the filling cavity is a closed end.

Optionally, the proximal end of the push tube extends into the interior of the connector; the balloon dilatation catheter further includes a first connection tube, and the first connection tube is arranged on the push tube by hot pressing. The proximal end of the connecting piece is used to close the proximal end of the filling cavity; the inner wall of the connecting piece is sealedly connected with the first connecting tube.

Optionally, the balloon dilatation catheter further comprises a second connecting pipe, the second connecting pipe is sleeved on the pushing pipe by means of hot pressing; at least part of the second connecting pipe is disposed on the connecting pipe inside of the connecting piece and sealingly connected with the inner wall of the connecting piece.

Optionally, the balloon dilation catheter further includes a stress diffusion tube sleeved on the outer surface of the proximal end of the push tube and disposed adjacent to the distal end of the connecting piece.

Optionally, the inner tube is further provided with developing elements, and the number of the developing elements is two, which are respectively arranged corresponding to the proximal end and the distal end of the balloon.

Compared with the prior art, the balloon dilatation catheter of the present invention has the following advantages:

First, the balloon dilatation catheter comprises a push tube, an inner tube and a balloon, the inner tube is arranged at the distal end of the push tube, and the balloon is sleeved on the outer surface of the inner tube; wherein , the push tube is formed by blending and extruding polylaurolactam and polyether block polyamide. The push tube made of the mixture of polylaurolactam and block polyetheramide has both good flexibility and supporting force, so that it can smoothly pass through calcified lesions and long occluded blood vessels.

Second, the balloon is a high-pressure balloon, which improves the pressure resistance of the entire balloon dilatation catheter and improves the dilation effect.

Third, the balloon dilatation catheter further includes a hydrophilic coating, and the hydrophilic coating covers at least the outer surface of the balloon and the outer surface of the distal end of the pushing tube. This allows the balloon dilation catheter to have less friction when it travels in the blood vessel, which is convenient for pushing, and the hydrophilic coating is not provided on the outer surface of the middle part and the proximal end of the pushing tube, so that the pushing The tube has good handling.

Description of drawings

The accompanying drawings are used for better understanding of the present invention and do not constitute any limitation to the present invention. in:

1 is a schematic structural diagram of a balloon dilatation catheter provided by the present invention according to an embodiment;

Fig. 2 is the A-A sectional view of the balloon dilatation catheter shown in Fig. 1;

Fig. 3 is the B-B sectional view of the balloon dilatation catheter shown in Fig. 1;

4 is a schematic diagram of the distal end of the original tubing of the pusher tube being cut when the inner tube of the balloon dilatation catheter is connected to the pusher tube according to an embodiment of the present invention;

5 is a schematic diagram of the inner tube of the balloon dilation catheter provided according to an embodiment of the present invention is connected to the push tube;

6 is a schematic diagram of the proximal end of the original pipe material of the pusher tube after being cut when the pusher tube of the balloon dilation catheter provided by the present invention is connected to the connector according to an embodiment of the present invention;

FIG. 7 is a schematic diagram of a push tube of a balloon dilation catheter provided according to an embodiment of the present invention when a first connecting tube and a second connecting tube are provided.

[reference number]:

100 - push tube, 100' - original tube;

110-filling cavity, 120-guide wire cavity; 130-hydrophilic coating;

200-inner tube;

300-balloon;

400 - tapered tip;

500-connector;

510-first joint, 520-second joint;

600 - Stress Diffusion Tube;

710 - the first connecting pipe, 720 - the second connecting pipe;

800 - developing element;

900 - heat shrink tubing.

detailed description

The embodiments of the present invention are described below through specific specific examples, and those skilled in the art can easily understand the advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the drawings provided in this embodiment are only used to illustrate the basic concept of the present invention in a schematic way, so the drawings only show the components related to the present invention rather than the number, shape and number of components in actual implementation. For dimension drawing, the type, quantity and proportion of each component can be changed at will in actual implementation, and the component layout may also be more complicated.

In addition, each embodiment of the following description has one or more technical features, but this does not mean that the person using the present invention must implement all the technical features in any embodiment at the same time, or can only implement different embodiments separately. One or all of the technical features of the . In other words, under the premise of possible implementation, those skilled in the art can selectively implement some or all of the technical features in any embodiment according to the disclosure of the present invention and according to design specifications or actual needs, or select The combination of some or all of the technical features in the multiple embodiments can be implemented flexibly, thereby increasing the flexibility of the implementation of the present invention.

As used in this specification, the singular forms "a," "an," and "the" include plural referents unless the content clearly dictates otherwise. As used in this specification, the term "or" is generally employed in its sense including "and/or" unless the content clearly dictates otherwise. As used in this specification, the terms "installed", "connected" and "connected" should be understood in a broad sense, for example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection, It can also be an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be an internal connection between two elements or an interaction relationship between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

In order to make the objects, advantages and features of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings. It should be noted that, the accompanying drawings are all in a very simplified form and in inaccurate scales, and are only used to facilitate and clearly assist the purpose of explaining the embodiments of the present invention. The same or similar reference numbers in the drawings represent the same or similar parts.

As used herein, the terms "proximal", "distal" are the relative orientation, relative position, orientation of elements or actions relative to each other from the perspective of the physician using the medical device, although "proximal", "distal" " is not limiting, but "proximal" generally refers to the end of the medical device that is closest to the physician during normal operation, and "distal" generally refers to the end that first enters the patient.

FIG. 1 shows a schematic structural diagram of a balloon dilatation catheter provided by an embodiment of the present invention, and FIG. 2 shows a cross-sectional view taken along line A-A of FIG. 1 . Please refer to FIG. 1 and FIG. 2 , the balloon dilation catheter includes a push tube 100 , an inner tube 200 and a balloon 300 , the inner tube 200 is disposed at the distal end of the push tube 100 , and the balloon 300 is sleeved on the outer surface of the inner tube 200 . Wherein, the push tube 100 is formed by blend extrusion of polylaurolactam (PA12) and polyether block polyamide (Pebax). The specific extrusion molding process is set according to the actual situation, as long as the polylaurolactam and the polyether block polyamide can be melted, mixed uniformly, and extruded to obtain the original pipe with a predetermined shape of the push pipe. The push tube 100 of the balloon dilatation catheter provided in this embodiment has both flexibility and support, so that the balloon dilatation catheter not only has good bending ability, but also has excellent pushing performance, ensuring that it can pass through Tortuous blood vessels, calcified lesions and long occluded blood vessels can improve performance.

Preferably, the mass ratio of polylaurolactam and polyether block polyamide is (1.5-9):1, for example (2-8):1, (2-7):1, (3-8) : 1, (2-6): 1. In a specific embodiment, the mass ratio of the polylaurolactam to the polyether block polyamide is 8:2. According to GB/T232-2010, a conventional three-point bending test device is used to test the toughness of the push pipe 100 made of the mixed material with this ratio. When the sample is pressed down by 4 mm, the force applied by the indenter to the sample is 1.5N-3.5N, indicating that the push tube 100 has good flexibility. In this embodiment, the trade mark of polylaurolactam is PA12: Grilamid L25, and the trade mark of polyether block polyamide is Pebax7233SA01MED.

The total length of the balloon dilatation catheter is 40cm-150cm. When the balloon dilation catheter is used to perform balloon dilation, the push tube 100 is used to transmit the push force applied by the operator, so that the balloon 300 can reach a predetermined position. During the advancement of the balloon 300, the distal end of the inner tube 200 is also provided with a tapered tip 400 for the convenience of guidance. The tapered tip 400 protrudes from the distal end of the balloon 300 . The tapered tip 400 is fabricated from a mixture of polyether block polyamide and titanium dioxide (TiO ₂ ). Further, the balloon dilatation catheter also includes a hydrophilic coating (not shown in the figure). The hydrophilic coating covers the outer surface of the tapered tip 400 , the outer surface of the balloon 300 and the outer surface of the distal end of the push tube 100 . The use of the hydrophilic coating can reduce the friction between the distal end of the balloon dilatation catheter and the blood vessel during the pushing process, which is easy to transport and reduces damage to the blood vessel wall. In an alternative embodiment, the hydrophilic coating may only cover the outer surface of the balloon 300 and the distal outer surface of the pusher tube 100 , but not the outer surface of the tapered tip 400 . The hydrophilic coating is not provided on the middle and the proximal end of the push tube 100, which can ensure that the push tube 100 has good maneuverability. In this embodiment, according to the length of the balloon 300, the length of the hydrophilic coating in the axial direction of the balloon dilation catheter is 300mm-500mm, for example, 350mm-500mm, 300mm-450mm, 350mm- 450mm. The main component of the hydrophilic coating may be polyvinylpyrrolidone, or may be formed by curing any existing hydrophilic coating composition, which will not be repeated in this embodiment.

Preferably, the balloon 300 is a high-pressure balloon, which can effectively expand in calcified blood vessels, fully open the diseased blood vessels, and improve the treatment effect. In this embodiment, the inner layer of the balloon 300 (ie, the part where the inner layer of the balloon is connected to the inner tube 200 ) is a low-compliance high-pressure balloon made of polylaurolactam. The high-pressure balloon has a diameter of 3.0mm-14.0mm, a length of 20mm-220mm, and can withstand a pressure of 16atm-3atm. Specifically, the balloon 300 includes an inner layer and an outer layer, the inner layer of the balloon is connected to the inner tube at the welding points at both ends of the balloon, and the inner layer and the outer layer are jointly enclosed to form a space for accommodating Filler lumen. The inner layer is extruded with polylaurolactam, and the outer layer is extruded with polyether block polyamide.

The use of the balloon dilation catheter is as follows: firstly, a guide wire is implanted in the patient; then, the balloon dilation catheter is threaded on the guide wire; then, the operator pushes the push tube The proximal end of 100 applies a pushing force to push the distal end of the balloon dilation catheter into the blood vessel along the guide wire and reach the lesion site; then, through the pushing tube 100, the balloon 300 is filled with filling agent , so as to expand the balloon 300 to open the narrowed blood vessel.

In order to achieve the above purpose, as shown in FIG. 3 , the pushing tube 100 includes a filling cavity 110 and a guide wire cavity 120 which are arranged in parallel along the axial direction and are isolated from each other. The distal end of the filling cavity 110 communicates with the balloon 300 , and the distal end of the guide wire cavity 120 communicates with the inner tube 200 . The cross section of the filling cavity 110 is crescent-shaped, and the cross section of the guide wire cavity 120 is circular. The push tube 100 with this structure utilizes its cross section to the maximum extent to construct the filling cavity 110, thereby shortening the filling and withdrawal time of the filling agent.

Further, the balloon dilation catheter further includes a connector 500 . The connector 500 is disposed at the proximal end of the push tube 100 and includes a first joint 510 and a second joint 520 . Wherein, the first connector 510 communicates with the filling cavity 110 , and the second connector 520 communicates with the guide wire cavity 120 . In this way, in actual use, the guide wire penetrates the tapered tip 400 , the guide wire lumen 120 and the second joint 520 . The first connector 510 is connected to a filling agent injector, and the filling agent injector fills the balloon 300 with a filling agent via the first connector 510 and the filling cavity 110 , and the filling agent may be a contrast agent or the like .

Optionally, the proximal end of the push tube 100 extends into the interior of the connecting member 500 to be connected with the connecting member 500 . The distance from the proximal end of the inflation lumen 110 to the proximal end of the balloon 300 is smaller than the distance from the proximal end of the guide wire lumen 120 to the proximal end of the balloon 300 . The proximal end of the filling cavity 110 is a closed end, and a perfusion hole (not shown in the figure) is provided on the proximal cavity wall of the filling cavity 110 . The first joint 510 communicates with the filling cavity 110 through the filling hole.

During the process of pushing the balloon dilation catheter, the operator applies a pushing force to the connecting piece 500 , and the pushing force is transmitted to the pushing tube 100 via the connecting piece 500 . In order to prevent the proximal end of the push tube 100 (specifically, the position of the push tube 100 corresponding to the position near the distal end of the connector 500) from being deformed by stress, the balloon dilation catheter preferably includes a stress diffusion tube 600 ( As shown in Figure 1). The stress spreading tube 600 is sleeved on the outer surface of the proximal end of the pushing tube 100 and is disposed adjacent to the distal end of the connecting member 500 . The stress diffusing tube 600 is made of a flexible material such as silica gel, and plays the role of diffusing stress.

Further, the balloon dilation catheter further includes a first connecting tube 710 (as shown in FIG. 7 ). The first connecting tube 710 is fixedly sleeved on the proximal end of the pushing tube 100 . The first connecting tube 710 and the pushing tube 100 are connected by thermocompression, and in the process of connecting the two, the first connecting tube 710 also closes the proximal end of the filling cavity 110 (specific method). will be described below). The inner wall of the connecting member 500 is sealedly connected to the first connecting pipe 710 through a glue dispensing or injection molding process. The balloon dilation catheter further includes a second connecting tube 720 . The second connecting pipe 720 is fixedly sleeved on the position corresponding to (ie, combined with) the distal end of the pushing pipe 100 and the connecting piece 500 by hot pressing, so that at least part of the second connecting pipe 720 The connecting pipe 720 is disposed inside the connecting piece 500 and is sealedly connected to the inner wall of the connecting piece 500 through a glue dispensing or injection molding process. The first connecting pipe 710 and the second connecting pipe 720 are used to realize the connection between the pushing pipe 100 and the connecting member 500, so as to improve the sealing performance and avoid leakage.

In this embodiment, the inner tube 200 is made of polylaurolactam. The distance from the distal end of the guide wire lumen 120 to the connector 500 is smaller than the distance from the distal end of the filling lumen 110 to the connector 500 . The cavity wall of the guide wire cavity 120 and the proximal tube wall of the inner tube 200 are formed integrally by hot pressing, so as to improve the connection strength of the push tube 100 and the inner tube 200 . The specific connection method of the two will be introduced in detail below.

Further, at least one imaging element 800 is provided on the distal end of the balloon dilatation catheter to display the position of the balloon 300 during the pushing process. The developing element 800 can be made of a developing metal such as platinum-iridium alloy, and is preferably disposed on the inner tube 200, which is safe and reliable. In this embodiment, the number of the developing elements 800 is two, and the two developing elements 800 are respectively disposed corresponding to the proximal end and the distal end of the balloon 300 .

Next, the assembly method of the inner tube 200 of the balloon dilatation catheter and the push tube 100, and the assembly method of the push tube 100 and the connector (not shown in FIG. 4 to FIG. 7 ) will be described herein with reference to FIG. 4 and FIG. 6 . .

The process of assembling the push tube 100 and the inner tube 200 is as follows:

1) Provide the original tubing 100' of the pusher tube 100 (the original tubing 100' has the filling lumen 110 and the guide wire lumen 120) and the inner tube 200, on the proximal and distal ends of the original tubing of the pusher tube, so The filling cavity 110 and the guide wire cavity 120 are both flush.

2) Cutting the lumen wall of the guide wire lumen 120 at the distal end of the original tubing 100', so that the distance from the distal end of the guide wire lumen 120 to the distal end of the filling lumen 110 is 4 mm-6 mm. Care should be taken not to damage the cavity wall of the filling cavity 110 during cutting. The distal end of the cut raw tubing 100' is shown in FIG. 4 . Then, insert a liner (not shown in the figure) into the inner tube 200 and the filling cavity 110 to support the tube wall of the inner tube 200 and the filling cavity 110 respectively, so as to avoid subsequent processing. During the process, the inner tube 200 and the filling cavity 110 are deformed.

3) Insert the proximal end of the inner tube 200 into the distal end of the guide wire lumen 120 (the outer diameter of the inner tube 200 is slightly smaller than the inner diameter of the guide wire lumen 120 to facilitate insertion and docking), and the The inner liner in the inner tube 200 is also inserted into the guide wire lumen 120 .

4) Put a heat shrinkable tube 900 on the connection between the inner tube 200 and the push tube 100 (as shown in FIG. 5 ).

5) Rotate the heat shrinkable tube 900, the heating temperature is 420°F-450°F, and the heating time is about 55s-65s.

6) After the heat shrinkable tube 900 is cooled, the heat shrinkable tube 900 is peeled off.

Samples were made by the above method, ten samples were heated at 420°F, 430°F, 440°F and 450°F, and the heating time of each sample was 60s. Observing the appearance of the connection between the inner pipe and the push pipe, it is found that when the heating temperature is 420°F, the appearance of the connection point meets the requirements, but when the heating temperature is 450°F, the material is severely deformed and the appearance of the connection point is defective. The tensile test is performed on the sample. Specifically, the two ends of the sample are clamped on a tensile instrument, and the sample is stretched at a certain tensile rate until the sample breaks, and the tensile strength is recorded and the result is displayed. in Table 1. It can be seen from Table 1 that when the heating temperature is 420°F, the tensile strength of the connection point is low and cannot meet the requirements for use. To sum up, when connecting the inner pipe and the push pipe, the heating temperature is preferably 430°F-440°F.

Table 1 Tensile strength of the connection point between the push tube and the inner tube

The process of assembling the push tube 100 and the connector is as follows:

1) Insert a liner into the filling cavity 110 and the guide wire cavity 120 of the original tube 100' of the push tube 100.

2) Cut the cavity wall of the filling cavity 110 at the proximal end of the original tube 100 ′ of the pushing tube 100 , so that the proximal end point of the filling cavity 110 and the proximal end end point of the guide wire cavity 120 are between The distance is 4mm-6mm, and care should be taken not to damage the lumen wall of the guide wire lumen 120 when cutting. The shape of the proximal end of the original pipe material 100' of the push pipe 100 after cutting is shown in FIG. 6 .

3) A perfusion hole is opened on the cavity wall of the filling cavity 110 on the side away from the guide wire cavity 120 . In the axial direction of the pushing tube 100 , the distance from the perfusion hole to the proximal end point of the guide wire lumen 120 is 24mm-28mm.

4) Determine the connection area on the push tube 100 . In the axial direction of the pushing tube 100 , the distance from the connecting region to the proximal end point of the guide wire lumen 120 is 48mm-52mm. A second connecting pipe 720 is sleeved on the second connecting region of the pushing pipe 100, the second connecting pipe 720 is made of polyether block polyamide, and the axial length is about 28 mm.

5) Put a heat shrinkable tube 900 on the push tube 100 and cover the second connecting tube 720 (as shown in FIG. 7 ).

6) Heating the heat shrinkable tube 900 so that the second connecting tube 720 is fixedly connected with the pushing tube 100 .

7) Take out the lining of the filling cavity 110 of the push tube 100, and fit a first connecting tube 710 to the proximal end of the push tube 100 without covering the perfusion hole (ie, The socket location is on the side of the perfusion hole near the proximal end of the push tube). The material of the first connecting pipe 710 is polyether block polyamide, and the length is about 15 mm.

8) Put another heat shrinkable tube 900 on the proximal end of the push tube 100 and cover the first connecting tube 710 (as shown in FIG. 7 ).

9) Heating the heat shrinkable tube 900 at a heating temperature of 190° C. and a heating time of 50 s, so that the first connecting tube 710 and the pushing tube 100 are fixedly connected. Since there is no lining in the filling cavity 110 , when the heat shrinkable tube 900 is thermally shrunk, the proximal end of the filling cavity 110 is melted to seal the proximal end of the filling cavity 110 .

10) After cooling, two of the heat shrinkable tubes 900 are peeled off.

11) Finally, insert the proximal end of the push tube 100 into the connecting piece, so that the first joint 510 is communicated with the perfusion hole, and the second connecting tube 720 is arranged at the far end of the connecting piece. end, and at least part of the second connecting tube 720 is located within the connector. The first connecting pipe 710 is sealedly connected to the inner wall of the connecting piece, and the second connecting pipe 720 is sealedly connected to the inner wall of the connecting piece through a process of dispensing or injection molding.

Those skilled in the art can understand that in the above process, the position of the connecting region, the position of the perfusion hole, the length of the first connecting pipe and the length of the second connecting pipe are all based on the balloon dilation catheter. size is properly set.

In the technical solution provided by the embodiment of the present invention, because the push tube is formed by blending polylaurolactam and polyether block polyamide, it has both reliable support and good flexibility, and can pass through tortuous When the blood vessel reaches the designated lesion site, it can fully dilate calcified or long occluded blood vessels. Those skilled in the art can understand that the balloon dilatation catheter provided by the embodiments of the present invention can also be applied to the expansion of arteriovenous fistulas and the post-expansion of stents.

Although the present invention is disclosed above, it is not limited thereto. Various modifications and variations can be made in the present invention by those skilled in the art without departing from the spirit and scope of the invention. Thus, provided that these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

A balloon dilatation catheter, characterized in that it comprises a push tube, an inner tube and a balloon, the inner tube is arranged at the distal end of the push tube, and the balloon is sleeved on the outer surface of the inner tube ; Wherein, the push pipe is formed by blending and extruding polylauractam and polyether block polyamide.
The balloon dilatation catheter according to claim 1, wherein the mass ratio of the polylaurolactam to the polyether block polyamide is (1.5-9):1.
The balloon dilatation catheter according to claim 1, wherein the balloon is a high pressure balloon.
The balloon dilatation catheter according to any one of claims 1-3, further comprising a hydrophilic coating covering the outer surface of the balloon and the outer surface of the pushing tube a distal outer surface; and/or, the balloon dilation catheter further comprises a tapered tip, the tapered tip is disposed at the distal end of the inner tube and protrudes from the distal end of the balloon; the A hydrophilic coating covers the outer surface of the tapered tip, the outer surface of the balloon, and the outer distal surface of the pusher tube.
The balloon dilation catheter according to claim 4, wherein in the axial direction of the balloon dilation catheter, the length of the hydrophilic coating is 300mm-500mm.
The balloon dilatation catheter according to claim 1, wherein the push tube comprises a filling lumen and a guide wire lumen which are arranged in parallel along the axial direction and are isolated from each other; the cross section of the filling lumen is crescent-shaped, and The distal end of the filling cavity communicates with the balloon; the cross section of the guide wire cavity is circular, and the distal end of the guide wire cavity communicates with the inner tube.
The balloon dilatation catheter according to claim 6, wherein the distal end wall of the guide wire cavity and the proximal end tube wall of the inner tube are formed integrally by means of heat pressing.
The balloon dilation catheter according to claim 6, further comprising a connecting piece, the connecting piece is disposed at the proximal end of the pushing tube and comprises a first joint and a second joint; the first joint is connected to The filling cavity is in communication, and the second joint is in communication with the guide wire cavity.
The balloon dilation catheter according to claim 8, wherein the distance from the proximal end point of the filling lumen to the proximal end point of the balloon is smaller than the distance from the proximal end point of the guide wire lumen to the balloon The proximal end point of the filling cavity is provided with a perfusion hole, the perfusion hole communicates with the first joint, and the proximal end of the filling cavity is a closed end.
The balloon dilation catheter according to claim 9, wherein the proximal end of the pushing tube extends into the interior of the connecting piece; the balloon dilation catheter further comprises a first connecting tube, the first connecting The tube is arranged at the proximal end of the push tube by hot pressing, and is used to close the proximal end of the filling cavity; the inner wall of the connecting piece is sealedly connected with the first connecting tube.
The balloon dilatation catheter according to claim 9, further comprising a second connection tube, the second connection tube is sleeved on the push tube by means of hot pressing; at least part of the second connection tube The pipe is arranged inside the connecting piece and is sealingly connected with the inner wall of the connecting piece.
The balloon dilatation catheter according to claim 8, further comprising a stress diffusion tube sleeved on the outer surface of the proximal end of the push tube and disposed adjacent to the distal end of the connecting piece.
The balloon dilatation catheter according to claim 1, wherein the inner tube is further provided with imaging elements, and the imaging elements are two in number, corresponding to the proximal end and the distal end of the balloon respectively. end settings.