Extended catheter

Abstract

The invention relates to an elongated catheter. The extension catheter comprises a catheter body, the catheter body is connected with a catheter base through a push rod, the far end of the catheter body comprises an inner tube and a shell arranged on the inner tube in a sleeving mode, and a metal net is arranged on the inner tube; at least two hole digging areas are formed in the metal net at the far end of the catheter body, and through holes enabling fluid to flow between the area outside the catheter body and the interior of the inner tube are formed in the hole digging areas. According to the scheme provided by the invention, metal burrs and burrs at the punching positions can be reduced, damage to blood vessels can be reduced, the overall flexibility and breaking strength of the catheter can be improved, and the fluid exchange speed of the internal area and the external area of the catheter main body can be increased.

Description

Technical Field

[0001] The present application relates to the technical field of medical devices, and in particular to an extension catheter. Background Art

[0002] Coronary arteries may sometimes be blocked or narrowed by atherosclerotic plaques or other lesions. These diseases are generally referred to as coronary heart disease or stenosis, and lead to insufficient blood flow to distal arteries and tissues, which can cause ischemic heart diseases such as angina pectoris and myocardial infarction. For these diseases, percutaneous coronary angioplasty (PCI) is generally required to dilate the narrowed part of the coronary artery of the heart using intravascular treatment devices such as stents and balloons to increase blood flow.

[0003] During PCI surgery, the tip of the guide catheter is usually inserted into the entrance of the coronary artery and left there, and the intravascular treatment device is delivered through the guide catheter. However, when the supporting force is small and the retention is unstable, the tip of the guide catheter sometimes falls off from the entrance of the coronary artery. Therefore, an extension catheter with a small diameter is inserted into the guide catheter to increase the supporting force of the guide catheter.

[0004] When the extension catheter goes deep into tortuous, calcified and other diseased blood vessels, the distal end of the diseased blood vessels will lose blood supply. Generally, a side hole is opened at one end of the extension catheter to solve the blood supply problem. However, the side holes of the extension catheters currently on the market have problems such as burrs and rough edges, which will cause serious damage to the blood vessels and make it difficult to solve the blood supply problem within the blood vessels. Summary of the invention

[0005] In order to solve or partially solve the problems existing in the related art, the present application provides an extension catheter, which can reduce the burrs and burrs at the punching position, reduce damage to blood vessels, and improve the overall flexibility and flexural strength of the extension catheter, thereby increasing the fluid exchange rate between the internal and external areas of the catheter body.

[0006] The first aspect of the present application provides an extension catheter, comprising:

[0007] Catheter seat and push rod;

[0008] A catheter body, wherein the catheter body is connected to the catheter seat through the push rod, and the distal end of the catheter body comprises an inner tube, and an intermediate layer is arranged on the inner tube;

[0009] At least two hole-digging areas are provided on the middle layer at the distal end of the catheter body, and through holes are provided in the hole-digging areas to enable fluid to flow between the area outside the catheter body and the inside of the inner tube.

[0010] In one embodiment, at least two support bars are fixedly arranged on the surface of the intermediate layer at uniformly spaced intervals in the circumferential direction, and the support bars are arranged along the length direction of the inner tube.

[0011] In one embodiment, the at least one through hole is circular.

[0012] In one embodiment, the at least one through hole is oval.

[0013] In one embodiment, the length and / or width of the through hole is 0.2 mm - 0.6 mm.

[0014] In one embodiment, the through holes on the distal end of the catheter body are distributed in a spiral pattern.

[0015] In one embodiment, a balloon is sleeved on the distal end of the catheter body, and the balloon is arranged on one side of the through hole.

[0016] The second aspect of the present application provides a method for manufacturing an extension catheter, including:

[0017] (1) Weaving metal wires on an inner tube covered with a lining film on its surface so that an intermediate layer is laid on the inner tube;

[0018] (2) Processing the intermediate layer by laser to form a plurality of dug-out areas and removing the lining film on the inner tube corresponding to the dug-out areas;

[0019] (3) Sleeving an outer tube on the inner tube and making the inner tube, the metal mesh and the outer shell form an integral body by means of fusion welding and heat sealing;

[0020] (4) Drilling holes on the corresponding plurality of dug-out areas of the outer tube so that a through hole is formed on each dug-out area.

[0021] In one embodiment, the dug-out area is diamond-shaped.

[0022] In one embodiment, step (2) further includes: installing support bars on the surface of the metal mesh by welding or pasting.

[0023] The technical solution provided by the present application may include the following beneficial effects:

[0024] The extension catheter of the present application includes a catheter hub; a catheter hub and a push rod;

[0025] The catheter body is connected to the catheter base through a push rod. The distal end of the catheter body includes an inner tube, and a metal mesh is provided on the inner tube. At least two perforated areas are formed on the metal mesh at the distal end of the catheter body, and through holes are provided in the perforated areas to enable fluid communication between the area outside the catheter body and the inside of the inner tube. This can reduce the metal burrs and flash at the punching positions, reduce the damage to blood vessels, and can improve the overall flexibility and anti-folding strength of the extension catheter, and increase the fluid exchange speed between the internal area and the external area of the catheter body.

[0026] It should be understood that the above general description and the following detailed description are only exemplary and explanatory, and do not limit this application. Brief Description of the Drawings

[0027] By describing the exemplary embodiments of the present application in more detail in conjunction with the drawings, the above and other objects, features, and advantages of the present application will become more apparent. Among them, in the exemplary embodiments of the present application, the same reference numerals generally represent the same components.

[0028] Figure 1 is a schematic structural diagram of the extension catheter shown in the embodiment of the present application;

[0029] Figure 2 is another schematic structural diagram of the extension catheter shown in the embodiment of the present application;

[0030] Figure 3 is a partially enlarged schematic structural diagram of the extension catheter shown in the embodiment of the present application;

[0031] Figure 4 is another partially enlarged schematic structural diagram of the extension catheter shown in the embodiment of the present application;

[0032] Figure 5 is a sectional view of the catheter body of the extension catheter shown in the embodiment of the present application;

[0033] Figure 6 is another sectional view of the catheter body of the extension catheter shown in the embodiment of the present application;

[0034] Figure 7 is a schematic structural diagram of the catheter body with a balloon of the extension catheter shown in the embodiment of the present application;

[0035] Figure 8 is another partially enlarged schematic structural diagram of the extension catheter shown in the embodiment of the present application.

[0036] The markings are as follows: 1. Catheter base; 2. Push rod; 3. Catheter body; 4. Inner tube; 5. Intermediate layer; 6. Outer tube; 7. Perforated area; 8. Through hole; 9. Support strip; 10. Balloon. Detailed Description of the Embodiments

[0037] Embodiments of the present application will be described in more detail below with reference to the accompanying drawings. Although the embodiments of the present application are shown in the drawings, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to make the present application more thorough and complete, and to fully convey the scope of the present application to those skilled in the art.

[0038] The terms used in the present application are for the purpose of describing specific embodiments only and are not intended to limit the present application. The singular forms "a", "the" and "said" used in the present application and the appended claims are also intended to include the plural forms unless the context clearly dictates otherwise. It should also be understood that the term "and / or" as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items. In the description of the present application, it should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present application.

[0039] Unless otherwise clearly defined and limited, the terms "mounted", "connected", "coupled", "fixed", etc. shall be construed broadly. For example, it may be a fixed connection, a detachable connection or an integral one; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the internal communication of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0040] It should be understood that although the terms "first", "second", "third", etc. may be used in the present application to describe various information, such information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of the present application, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present application, the meaning of "a plurality" is two or more unless otherwise specifically defined.

[0041] For ischemic heart diseases such as angina pectoris and myocardial infarction, percutaneous coronary intervention (PCI) is generally required, which involves using intravascular treatment devices such as stents and balloons to dilate the stenotic part of the coronary artery of the heart to increase blood flow. At this time, usually after inserting the end of a tubular guiding catheter into the entrance of the coronary artery and leaving it in place, the intravascular treatment device is delivered through the guiding catheter, thereby improving the insertability of the intravascular treatment device towards the distal side of the coronary artery. However, in the case of low supporting force and unstable retention as described above, the end of the guiding catheter sometimes detaches from the entrance of the coronary artery. In this case, by inserting an extension catheter with a smaller diameter into the guiding catheter and making the extension catheter protrude from the distal opening of the guiding catheter, the supporting force of the guiding catheter is improved; but at the same time, when the extension catheter penetrates into tortuous, calcified and other diseased blood vessels, the distal part of the diseased blood vessel often loses blood supply. Therefore, several side holes are generally opened on the extension catheter to solve the blood supply problem. Currently, the side hole design of the extension catheter on the market is unreasonable, resulting in insufficient blood flow capacity through the side holes, or the side holes are too large, which reduces the supporting property and anti-folding strength of the guiding extension catheter. Secondly, there will be burrs and flash around the position of the side holes, which will damage the blood vessels.

[0042] In one of the ways of drilling holes in the extension catheter, a metal ring can be embedded at the position where drilling is required to replace the metal mesh on the inner tube of the extension catheter. The drilling position is on the metal ring, and drilling can be carried out avoiding the metal mesh. The edge of the side hole formed by this drilling method is complete, and there are basically no defects such as burrs and flash on the inner and outer surfaces of the side hole, which can reduce the damage to the blood vessels. However, due to embedding a metal ring, the overall flexibility and passability of the guiding catheter will be greatly affected.

[0043] In one of the ways of drilling holes in the extension catheter, drilling can be directly carried out on the metal mesh, but defects such as metal burrs and flash will appear at the drilling position, which will cause serious damage to the blood vessels and the instruments passing through the inner tube of the guiding catheter. Secondly, due to the unreasonable size, shape, quantity, position, and arrangement of the holes, the blood reflux effect during the use of the guiding catheter is not good.

[0044] In view of the above problems, the embodiment of the present application provides an extension catheter, which can reduce the metal burrs and flash at the drilling position, reduce the damage to the blood vessels, and can improve the overall flexibility and anti-folding strength of the extension catheter, and improve the fluid exchange speed in the internal and external regions of the catheter body.

[0045] The technical solutions of the embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0046] Figure 1 is a schematic structural diagram of the extension catheter shown in the embodiment of the present application.

[0047] See Figure 1, An extended catheter, comprising: a catheter hub 1, a pusher rod 2 and a catheter body 3. The catheter body 3 is connected to the catheter hub 1 through the pusher rod 2. The pusher rod 2 can be a wire, a hypotube, a shaft, a partial shaft or any other device obvious to those skilled in the art. The catheter hub 1 is connected to the pusher rod 2 and is placed outside the patient's body. The catheter hub 1 places the catheter body 3 at the target position through the pusher rod 2. Other instruments can enter the inside of the catheter body 3 through the catheter hub 1. Product information is set on the catheter hub 1, which is beneficial for the operator to withdraw the catheter body 3 from the patient's blood vessel. The catheter hub 1 and the pusher rod 2 can be formed of materials such as but not limited to stainless steel, nitinol, titanium alloy or other materials suitable for the purposes disclosed herein; the distal end of the catheter body 3 includes an inner tube 4, an intermediate layer 5 and an outer tube 6 sleeved on the intermediate layer 5. The intermediate layer 5 can be formed of a metal material. The inner tube 4 can be formed of materials such as but not limited to polytetrafluoroethylene (PTFE), perfluoroalkoxy alkane (PFA), high-density polyethylene (HDPA) or other materials suitable for the purposes described herein. The intermediate layer 5 is provided on the inner tube 4; at least two through holes 8 are provided on the distal end of the catheter body 3 to enable fluid circulation between the area outside the catheter body 3 and the inside of the inner tube 4. A radiopaque tip is also provided at the front end of the catheter body 3 away from the catheter hub 1. The radiopaque tip can be made of tungsten powder, heavy metal or a polymer of heavy metal salt.

[0048] In one embodiment, the outer tube 6 sleeved on the inner tube 4 has a tubular shape substantially the same as that of the inner tube 4. The outer tube 6 can provide a certain protection ability and flexibility ability. The outer tube 6 can be formed of materials such as but not limited to thermoplastic elastomer, nylon or other materials suitable for the purposes described herein. The thermoplastic elastomer is, for example but not limited to, polyether block amide (such as Pebax, PE, etc.).

[0049] In one embodiment, at least two support bars 9 are fixedly arranged on the surface of the intermediate layer 5 at circumferentially evenly spaced intervals by means of glue bonding or welding. The support bars 9 can be formed of materials such as metal or resin. Grooves corresponding to the support bars 9 are provided inside the outer tube 6. When installing, the support bars 9 and the grooves can be fitted for installation. In a specific embodiment, the support bars 9 can be arranged outside the intermediate layer 5, and the intermediate layer 5, the support bars 9 and the outer tube 6 are combined into one body by means of hot melting.

[0050] In one embodiment, two support bars 9 are fixedly and symmetrically arranged on the surface of the intermediate layer 5. Two grooves corresponding to the support bars 9 are provided inside the outer tube 6. In one embodiment, three support bars 9 are arranged on the surface of the intermediate layer 5, and the three support bars 9 are arranged in a 120° rotationally symmetric arrangement on the intermediate layer 5. By arranging the support bars 9 on the intermediate layer 5, the supportability and anti-folding strength of the catheter body 3 can be improved.

[0051] In one embodiment, the through-hole 8 can be circular or oval, and the length and / or width of the through-hole 8 is 0.2 mm - 0.6 mm. By adjusting the shape and size of the through-hole 8, it can have a good blood reflux effect during use, and at the same time, the bending resistance strength and stability of the extension catheter can be improved.

[0052] In one embodiment, the through-holes 8 on the distal end of the catheter body 3 away from the catheter seat 1 are distributed in a spiral distribution form, and the shortest distance between two adjacent through-holes is the sum of the radii or widths of the two through-holes, avoiding overlap between two adjacent through-holes, which can improve the support and bending resistance strength of the extension catheter.

[0053] In one embodiment, a balloon 10 is sleeved on the distal end of the catheter body 3 away from the catheter seat 1, and the balloon 10 is located on the front side of the through-hole 8. The balloon 10 can better fix the extension catheter, which is beneficial to improving the stability of the extension catheter.

[0054] Corresponding to the foregoing embodiment of the extension catheter, the present application also provides a manufacturing method of an extension catheter, which includes: (1) weaving an intermediate layer 5 with a weaving structure on an inner tube 4 covered with an inner lining film on its surface; (2) welding the intermediate layer 5 by laser to form a plurality of dug-out areas 7 and removing the inner lining film on the inner tube corresponding to the dug-out areas 7; (3) sleeving an outer tube 6 on the inner tube 4 and making the inner tube 4, the intermediate layer 5 and the outer tube 6 form an integral body by means of fusion heat sealing; (4) punching holes on the corresponding plurality of dug-out areas 7 of the outer tube 6 so that a through-hole is formed on each dug-out area 7.

[0055] In one embodiment, step (2) further includes: installing support bars 9 on the surface of the intermediate layer 5 by means of welding or pasting. The support bars 9 can be 2 or 3. Using the structure of the support bars 9 in the catheter body 3 can not only strengthen the bending resistance performance of the catheter body 3, but also improve the support strength of the catheter body 3 to a certain extent, and strengthen the operator's confidence in operating the instrument.

[0056] In one embodiment, the dug-out area 7 is diamond-shaped. Setting the dug-out area 7 as diamond-shaped can make the dug-out area 7 of the intermediate layer 5 more regular, thereby avoiding metal burrs and flash.

[0057] In one embodiment, punching can be performed on the distal end of the catheter body 3 at 3 - 24 cm using a punching device. For example, 24 through-holes can be punched, one through-hole is punched every 3 mm, and the through-holes are distributed in a 90° spiral distribution form. Through this arrangement of the through-holes, the blood reflux effect can be better improved.

[0058] In one embodiment, metal wires can be woven on a metal inner tube with an inner lining film on its surface so that the metal wires have a woven structure to form an intermediate layer. Laser spot welding is performed on the intermediate layer to obtain multiple punched areas. After removing part of the metal mesh (punched areas) using the laser spot welding process, the metal mesh can still maintain its woven structure, and the edges of the punched areas of the metal mesh are flat and firm. At the same time, the inner lining film on the inner tube corresponding to the punched areas is removed by laser. The support strips are fixed to the metal mesh by gluing or welding. The grooves on the outer tube are aligned with the support strips, and the outer tube is installed on the inner tube by heat sealing and welding. Finally, holes are drilled on the outer tube corresponding to the multiple punched areas using a drilling device so that a through hole is formed on each punched area to obtain multiple through holes. By means of heat sealing and welding, the inner tube, the metal mesh, and the outer tube can be integrated into one body, making the surface of the extension catheter smooth and flat, reducing the metal burrs and flash near the through holes, ensuring the original performance while not damaging the instrument passing ability of the extension catheter, and reducing the risk of ischemia caused by the long-term use of the extension catheter in blood vessels.

[0059] The extension catheter of the present application includes a catheter hub; a catheter body, the catheter body is connected to the catheter hub through a pusher rod, the distal end of the catheter body includes an inner tube and an outer tube sleeved on the inner tube, and metal wires with a woven structure are arranged on the inner tube; at least two through holes are arranged on the distal end of the catheter body to enable fluid communication between the area outside the catheter body and the inner tube, the through holes penetrate through the outer tube and communicate with the inside of the inner tube, which can reduce the metal burrs and flash at the punching positions, reduce the damage to blood vessels, and can improve the overall flexibility and bending strength of the extension catheter, and improve the fluid exchange speed between the inner area and the outer area of the catheter body.

[0060] Regarding the device in the above embodiments, the specific manners in which each module performs operations have been described in detail in the embodiments related to the method, and will not be elaborated here in detail.

[0061] The embodiments of the present application have been described above. The above description is exemplary and not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes are obvious to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The selection of the terms used herein is intended to best explain the principles of the embodiments, practical applications, or improvements to the technologies in the market, or to enable other ordinary skilled persons in the art to understand the embodiments disclosed herein.

Claims

1. An extended catheter, characterized in that, include: Catheter seat and push rod; A catheter body, wherein the catheter body is connected to the catheter seat through the push rod, and the distal end of the catheter body comprises an inner tube, and an intermediate layer is arranged on the inner tube; At least two hole-digging areas are provided on the middle layer at the distal end of the catheter body, and through holes are provided in the hole-digging areas to enable fluid to flow between the area outside the catheter body and the inside of the inner tube.

2. The extended catheter according to claim 1, wherein, At least two support bars evenly spaced along the circumferential direction are fixedly arranged on the surface of the intermediate layer, and the support bars are arranged along the length direction of the inner tube.

3. The extended catheter according to claim 1, characterized in that, The at least one through hole is circular.

4. The extended catheter according to claim 1, characterized in that, The at least one through hole is oval in shape.

5. The extended catheter according to claim 1, characterized in that, The length and / or width of the through hole is 0.2 mm-0.6 mm.

6. The extended catheter according to claim 1, wherein The through holes on the distal end of the catheter body are distributed in a spiral distribution.

7. The extended catheter according to claim 1, characterized in that, A balloon is sleeved on the distal end of the catheter body, and the balloon is arranged on one side of the through hole.

8. A manufacturing method of an extension catheter according to any one of claims 1-7, characterized in that, include: (1) Weaving metal wires on an inner tube covered with an inner lining film so that an intermediate layer is laid on the inner tube; (2) processing the middle layer by laser to form a plurality of hole-digging areas and removing the inner lining film on the inner tube corresponding to the hole-digging areas; (3) The outer shell is placed on the inner tube and the inner tube, the middle layer and the outer tube are integrated by welding and heat sealing; (4) Punching holes on the corresponding multiple hole-digging areas of the outer tube so that a through hole is formed on each hole-digging area.

9. The manufacturing method according to claim 8, characterized in that, The hole-digging area is in a rhombus shape.

10. The manufacturing method according to claim 8, characterized in that, Step (2) also includes: installing the support bar on the surface of the intermediate layer by welding or gluing.

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