WO2017033535A1

WO2017033535A1 - Catheter

Info

Publication number: WO2017033535A1
Application number: PCT/JP2016/067676
Authority: WO
Inventors: 筒井　宣政; 筒井　康弘; 宏成加藤
Original assignee: 株式会社東海メディカルプロダクツ
Priority date: 2015-08-24
Filing date: 2016-06-14
Publication date: 2017-03-02
Also published as: JP6559502B2; JP2017042222A

Abstract

The present invention addresses the problem of providing a catheter configured so as to ensure the flexibility of a front end section and also to ensure the tensile strength between the front end section and the catheter body. This catheter 100 is characterized by comprising: a catheter body 10 having an inner resin layer 11, a reinforcing metallic wire 12 which is disposed on the outer periphery of the inner resin layer, and an outer resin layer 13 which covers the outer periphery of the reinforcing metallic wire; and a front end section 50 formed at the distal end of the catheter body, a cylindrically formed resin mesh 30 being disposed straddling the catheter body and the front end section.

Description

catheter

The present invention relates to a catheter.

A taper-shaped resin tip is provided at the distal end of the catheter body made of a coiled body, so that high flexibility and excellent torque transmission are sufficiently exhibited, and the distal end of the catheter body and the tip are close to each other. An improved catheter has been proposed so that the occurrence of stress concentration at the boundary between the distal end and the distal end can be advantageously prevented, and torque transmission at the boundary can be advantageously increased.

Such a catheter has a distal end portion of a catheter body having a hollow coil body in which an outer peripheral surface and an inner peripheral surface are respectively covered with an outer resin layer and an inner resin layer, and at least a distal end side portion is a tapered portion. In addition, a braided body extending in the axial direction across the catheter body and the tip is embedded in each of the catheter body and the tip (Patent Document 1). .

Such a catheter does advantageously prevent stress concentration from occurring at the boundary between the distal end of the catheter body and the proximal end of the tip, and torque transmission at such a boundary is advantageous. This is an effective invention in that it can be improved.

However, there are many types of catheters in which a distal end portion made of a different material is attached to the distal end of a catheter body having a reinforcing metal net assembly in order to ensure flexibility. In such a catheter, there is a possibility that the stress concentrates at the boundary with the strengthened mesh assembly and breaks or breaks. Also, a metal marker or the like is often attached to the tip of the net assembly, but with such a catheter, the possibility of the marker falling off if the tip breaks cannot be wiped off. Therefore, it is necessary to take measures to prevent such danger in advance.

JP 2010-88833 A

Therefore, the present invention has been made in view of the above problems, and even if stress is concentrated on the boundary between the distal end portion and the catheter main body, the tensile strength between the distal end portion and the catheter main body can be ensured, and the fracture occurs. It is an object of the present invention to provide a catheter that can be prevented from being broken or torn, and at the same time, can prevent a marker or the like from dropping off.

The present invention employs the following means in order to achieve the above-described object.

The catheter of the present invention has an inner resin layer, a reinforcing metal wire disposed on the outer periphery of the inner resin layer, and an outer resin layer disposed on the outer periphery of the reinforcing metal wire,
The distal end side of the catheter body, the inner resin layer, the reinforcing metal wire disposed on the outer periphery of the inner resin layer, and the resin disposed on at least a part of the outer periphery of the reinforcing metal wire A middle portion having a net made and a tip outer resin layer disposed on the outer periphery of the resin net,
Distal side of the intermediate portion, the inner resin layer, the resin net disposed on the outer periphery of the inner resin layer, and the tip outer resin layer disposed on the outer periphery of the resin net And a tip having
It is characterized by having.

According to the catheter of the present invention, since the resin net is arranged across the portion having the reinforcing metal wire and the portion not having the reinforcing metal wire, stress is concentrated on these boundaries when the catheter is used. However, since the tensile strength is secured by the resin net, it is possible to prevent breakage at the boundary between the portion having the reinforcing metal wire and the portion not having the reinforcing metal wire. Further, when the resin net is provided only on a part of the outer periphery, the force required to bend the side where the resin net is present and the side where the resin net is not present can be different. Thereby, it can produce so that bending rigidity may change with the directions which a front-end | tip part bends.

In the catheter according to the present invention, the resin net may be formed in a cylindrical shape. By adopting a cylindrical resin net, if the length is changed by pulling both ends of the resin net, the diameter of the cylinder can be easily changed. Therefore, even if the portion having the reinforcing metal wire and the portion not having the reinforcing metal wire have different diameters, they can be fitted and attached so as to correspond to the respective diameters.

In the catheter according to the present invention, each metal wire of the reinforcing metal wire and each resin thread of the resin net are 45 ° to 89 ° with respect to the axial direction of the catheter body, The difference may be within 10 °. By making the knitting angle between each metal wire of the reinforcing metal wire and each resin yarn of the resin net (the angle formed by each metal wire and each resin yarn with respect to the axial direction) closer, the resin net is made of metal. It becomes easy to get caught in the wire, and the main body and the resin net can be firmly fixed. Moreover, since the overlapping part with a metal wire decreases, it can prevent that the middle part and the front-end | tip part of a catheter become thick as a whole.

Furthermore, the catheter according to the present invention may be characterized in that the reinforcing metal wire is further provided on the outer periphery of the resin net. By adopting such a configuration, the resin net is sandwiched between metal wire layers, so the resin net and the reinforcing metal wire can be more firmly fixed, and the portion having the reinforcing metal wire and the reinforcement It is possible to further prevent the possibility of breaking with a portion not having the metal wire.

Furthermore, in the catheter according to the present invention, the resin net may be characterized in that a resin thread constituting the net portion is coated with an adhesive. By adopting such a configuration, the inner peripheral resin layer and the outer resin layer can be strongly fixed by adhesion. In particular, the length of the resin net can be temporarily fixed by using an adhesive having adhesiveness before processing, so that the resin net can be easily attached to the catheter body at the time of production. it can.

Furthermore, in the catheter according to the present invention, the distal end portion may be provided with an X-ray marker on the inner peripheral side of the resin net. By adopting such a configuration, since the marker is surrounded by the resin net, it is possible to prevent the marker from dropping even if the tip portion is broken.

Furthermore, the catheter according to the present invention may be characterized in that the distal end portion includes a second reinforcing metal wire. By adopting such a configuration, the strength of the tip can be further improved.

Furthermore, in the catheter according to the present invention, the second reinforcing metal wire may be a coil marker. As a result, the position of the tip can be easily confirmed with X-rays.

According to the catheter of the present invention, even if stress is concentrated on the boundary between the distal end portion and the catheter main body, the tensile strength between the distal end portion and the catheter main body can be ensured, and it is prevented from being broken or torn. A catheter can be provided.

FIG. 1 is a schematic side view of a catheter device 110 having a catheter 100 and a hand operation unit 200 according to the first embodiment. FIG. 2 is an enlarged schematic side view showing the AA portion of FIG. 3A and 3B are views showing a part of a catheter manufacturing process according to the first embodiment. 4A and 4B are diagrams illustrating a part of a manufacturing process of the catheter according to the first embodiment. FIG. 5 is a diagram illustrating a part of a catheter manufacturing process according to the first embodiment. FIG. 6 is a view showing a catheter according to the second embodiment. FIG. 7A is a view showing a catheter according to the third embodiment, and FIG. 7B is a schematic view showing a resin net 30 used in the third embodiment. 8A and 8B are diagrams illustrating a part of a manufacturing process of a catheter according to the third embodiment. FIG. 9 is a view showing a catheter according to the fourth embodiment. 10A and 10B are views showing another embodiment of the catheter according to the embodiment. 11A and 11B are diagrams showing another embodiment of the catheter according to the embodiment. FIG. 12 is a graph showing the results of a tensile test.

Hereinafter, the catheter 100 according to the present invention will be described in detail with reference to the drawings.

(First embodiment)
FIG. 1 is a schematic side view of the catheter device 110 according to the first embodiment, and FIG. 2 is an enlarged schematic side view of the AA portion of FIG.

As shown in FIG. 1, the catheter device 110 according to the embodiment includes a catheter 100 and a hand operation unit 200, and the catheter 100 is provided on the catheter body 10 and on the distal end side of the catheter body 10. A middle portion 40 and a tip portion 50 are provided.

The catheter body 10 has a hollow inner resin layer 11 and a reinforcing metal wire disposed on the outer periphery of the inner resin layer 11 as shown in FIG. 2 except for the middle portion 40 and the tip portion 50 on the distal end side. 12 and an outer resin layer 13 disposed on the outer peripheral side of the reinforcing metal wire 12.

The inner resin layer 11 is a tubular member that is disposed on the innermost side and has a core lumen 19 in the center, as shown in FIG. The core lumen 19 is used for passing a guide wire (not shown) or injecting a drug solution according to the use application of the catheter 100. The material of the inner resin layer 11 is not particularly limited. For example, if it is used for passing a guide wire, polytetrafluoroethylene having high slidability with the guide wire may be used. Further, the inner resin layer 11 is not necessarily a single resin layer. For example, a material that is resistant to liquids such as chemicals and blood is used on the inner peripheral side, and the inner resin layer 11 is disposed on the outer peripheral side. It may be formed in a two-layer structure, such as using a material having high adhesion and compatibility with the reinforcing metal wire 12. In addition, this inner side resin layer 11 is continuously arrange | positioned also in both the intermediate | middle part 40 and the front-end | tip part 50 so that it may mention later.

The reinforcing metal wire 12 is disposed on the outer peripheral side of the inner resin layer 11 and is provided for imparting strength to the catheter 100 or improving torque transmission. As a structure of the reinforcing metal wire 12, there are a form in which the metal wire is spirally wound around the outer periphery of the inner resin layer 11, a form knitted in a mesh form, a form woven in a mesh form, and the like. The thickness of the reinforcing metal wire 12 is not particularly limited, but preferably about 10 μm to 100 μm. Further, the reinforcing metal wire 12 is not limited to a circular cross section, and a flat wire may be used.

The type of metal material constituting the reinforcing metal wire 12 is not particularly limited. Preferably, for example, tungsten, platinum, titanium, stainless steel or the like is used. Tungsten can be used more suitably because it is highly visible by X-ray and inexpensive.

The outer resin layer 13 constitutes the outermost layer of the catheter body 10. The inside of the catheter body 10 is protected, and the reinforcing metal wire 12 is prevented from being exposed to the outside, and has a function of being melted at the time of molding and integrated with the reinforcing metal wire 12 to fix these positions. The resin material of the outer resin layer 13 is not particularly limited. Any resin having moderate flexibility and capable of protecting the outside can be used. Preferably, polyamide or the like can be used.

The middle portion 40 is provided on the distal side of the catheter body 10, and includes a hollow inner resin layer 11, a reinforcing metal wire 12 disposed on the outer periphery of the inner resin layer 11, and the reinforcing metal wire 12. The resin net 30 disposed on the outer periphery side of the resin net 30 and the tip end outer resin layer 51 disposed on the outer periphery of the resin net 30 are provided.

Since the inner resin layer 11 is the same as the inner resin layer 11 of the catheter body 10, description thereof is omitted. Further, since the reinforcing metal wire 12 is the same as the reinforcing metal wire 12 of the catheter body 10, the description thereof is omitted.

The resin net 30 is formed in a net shape by a net assembly of thread-like resin of about 1 μm to 100 μm. As a material for the resin net 30, it is desirable to use a resin having a melting point higher than that of the material of the tip end outer resin layer 51. This is because when the outer resin layer 13 is molded at a high temperature, the resin net 30 will not function as a net if it is dissolved. For example, a polyester resin or a PET resin can be preferably used.

The distal end outer resin layer 51 is a resin layer constituting the outermost layer on the distal end side of the catheter 100 and melts at the time of molding to be integrated with the reinforcing metal wire 12 and the resin net 30 to fix these positions. And a function of protecting the outer periphery of the middle portion 40. Further, by using a material that is more flexible than the outer resin layer 13 of the catheter body 10 for the distal end outer resin layer 51 or using a hard resin on the contrary, an intermediate layer having a different flexibility from the catheter body 10 is used. It can be set as the part 40 and the front-end | tip part 50. FIG.

The front end portion 50 includes an inner resin layer 11, a resin net 30 disposed on the outer peripheral side of the inner resin layer 11, and a front end outer resin layer 51 disposed on the outer periphery of the resin net 30. .

The inner resin layer 11 is the same as the inner resin layer 11 of the catheter body 10 and is a continuous integral molding. Further, the resin net 30 and the distal end portion outer resin layer 51 are the same as the resin net 30 and the distal end portion outer resin layer 51 of the middle portion 40 and are a continuous and integrally formed product. The resin net 30 may be provided on the entire tip portion 50 or a portion that is not provided on the distal end. That is, it is only necessary to be provided at the boundary between the middle portion 40 and the tip portion 50.

The distal end outer resin layer 51 has a function of preventing the reinforcing metal wire 12 and a resin net 30 to be described later from being exposed to the outside, and melting and integrating them with each other to fix these positions during molding. .

In the catheter 100 according to the present invention, the resin net 30 is disposed so as to straddle the middle portion 40 where the reinforcing metal wire 12 is disposed and the distal end portion 50 where the reinforcing metal wire 12 is not disposed. Yes. That is, in the middle portion 40, the resin net 30 is disposed on the outer peripheral side of the reinforcing metal wire 12 and on the inner peripheral side of the distal end portion outer resin layer 51, and in the distal end portion 50, the inner resin layer 11 and The resin net 30 is disposed between the front end portion outer resin layers 51. By adopting such a structure, it is possible to increase the tensile strength and the torsional strength at the boundary between the middle portion 40 and the tip portion 50, that is, the boundary between the portion where the reinforcing metal wire 12 is present and the portion where the reinforcing metal wire 12 is not present. Further, since the resin net 30 is arranged on the outer peripheral side of the reinforcing metal wire 12, it is possible to reduce the concentration of stress between the middle portion 40 and the tip portion 50, and at the boundary portion. It is possible to prevent the outer peripheral side of the distal end outer resin layer 51 from breaking.

Next, a method for producing the catheter 100 configured as described above will be described. First, as shown in FIG. 3A, a catheter tube 130 having an inner resin layer 11, a reinforcing metal wire 12, and an outer resin layer 13 is prepared. And the outer side resin layer 13 of the part which comprises the front-end | tip part 50 and the intermediate | middle part 40 is melt | dissolved with a solvent, and the reinforcement metal wire 12 of the part which comprises the front-end | tip part 50 is then melt | dissolved and removed with a solvent ( (See FIG. 3B). The removal method is not limited to dissolution, and may be physically removed. Next, as shown in FIG. 4A, the resin net 30 is placed so as to straddle both the middle portion 40 and the tip portion 50. As shown in FIG. 4B, the end outer resin layer 51 is formed on the tip 50 as shown in FIG. 5 in a state where the ends are aligned or overlapped while winding a single resin net 30. A resin tube 51a is attached. By molding by thermal processing in this state, the tip outer resin layer 51 is melted, and the resin net 30 made of a resin having a melting point higher than that of the tip outer resin layer 51 is not melted. The resin is cured with the resin net 30 entering the outer resin layer 51, the resin net 30 is fixed in the distal end outer resin layer 51, and the catheter 100 is completed (see FIG. 2).

In the catheter 100 thus manufactured, the resin of the distal end outer side resin layer 51 enters between the resin nets 30, so that they are firmly fixed and difficult to come off. Further, since the resin net 30 is provided across the middle portion 40 and the tip portion 50, the strength of each connection portion can be improved and the tensile strength can be improved. Therefore, even if stress concentrates at the tip of the reinforcing metal wire 12, it can be prevented from breaking. In addition, since the reinforcing metal wire 12 is not provided at the distal end portion 50 and the resin net 30 is made of a synthetic resin, the flexibility of the distal end portion 50 can be ensured.

(Second Embodiment)
A catheter 100 according to the second embodiment is shown in FIG. The catheter 100 according to the second embodiment is different in that the resin net 30 has a side surface that is not provided in part so as to have a gap, not the entire circumference of the middle portion 40 and the distal end portion 50. Since the other points are the same as in the first embodiment, description thereof is omitted.

By providing the resin net 30 as in the catheter 100 according to the second embodiment, it is possible to provide a difference in bending rigidity depending on the direction of bending between the portion having the resin net 30 and the portion not having it. That is, it is possible to provide a direction in which bending is difficult (back side in FIG. 6) and a direction in which bending is easy (front side in FIG. 6).

(Third embodiment)
A catheter 100 according to a third embodiment is shown in FIG. The catheter 100 according to the third embodiment is different from the catheter 100 according to the first embodiment in that the resin net 30 is formed in a cylindrical shape from the beginning as shown in FIG. 7B. Other points are the same as in the first embodiment.

When the cylindrical resin net 30 is used, as shown in FIG. 8A, the resin net 30 is placed so as to straddle both the middle portion 40 and the tip portion 50 from the distal end side. Then, from this state, as shown in FIG. 8B, the end of the resin net 30 is pulled so that the entire length of the resin net 30 becomes long. Accordingly, the inner diameter of the resin net 30 is shortened, and the resin net 30 can be adjusted to an inner diameter having the same length as the outer diameter of the middle portion 40 and the outer diameter of the tip portion 50. The outer periphery of the middle part 40 and the front end part 50 can be covered exactly. At this time, even if the diameters of the catheter body 10 and the distal end portion 50 are different from each other, the diameter of the resin net 30 is changed depending on the part by adjusting the pulling degree of each part of the resin net 30. Since it can be done, it can cover any part exactly.

According to the catheter according to the third embodiment, by using the resin net 30 formed in a cylindrical shape, the diameter of the resin net 30 that is cylindrical when twisted or pulled is small. Therefore, the inner resin layer 11 or the reinforcing metal wire 12 is further tightened by twisting or pulling during use. For this reason, the strength of the joint can be increased by twisting or pulling during use.

Further, as in the third embodiment, by using the resin net 30 made in a cylindrical shape in advance, it can be attached regardless of the diameter, material, shape, surface state, etc. of the connection target. For example, even if the diameter of the middle portion 40 and the tip portion 50 are different or the material is a different member, it can be produced without any problem. The resin net 30 can adjust the bending rigidity of the distal end of the catheter by adjusting the tension in the longitudinal direction when the resin net 30 is fixed. That is, the cylindrical net-like resin net 30 can be formed into a tip portion 50 having a high bending rigidity, that is, difficult to bend by attaching in a more stretched state (long and short in diameter), and does not pull too much. By attaching in the state, it can be set as the front-end | tip part 50 with weak bending rigidity, ie, easy to bend.

(Fourth embodiment)
A catheter 100 according to a fourth embodiment is shown in FIG. In the catheter 100 according to the fourth embodiment, the knitted state of each metal wire of the reinforcing metal wire and each resin yarn of the resin net is formed in substantially the same manner. Other points are the same as in the first embodiment. Each metal wire of the reinforcing metal wire and each resin thread of the resin net are 45 ° to 89 ° with respect to the axial direction of the catheter body, and the respective angle differences are formed within 10 °. Is preferred. By adopting such a configuration, the resin net 30 can be easily borrowed from the metal wire, and the resin net 30 can be firmly fixed to the middle portion 40 or the tip portion 50. Moreover, since there are few overlapping parts with a metal wire, even if it is a case where the resin net 30 is coat | covered, it can reduce that the middle part 40 and the front-end | tip part 50 become thick.

It should be noted that the present invention is not limited to the above-described embodiments, and it goes without saying that the present invention can be implemented in various modes as long as it belongs to the technical scope of the present invention.

In the above-described embodiment, the distal end portion 50 of the catheter 100 has the same diameter and the same thickness as the catheter body 10, but is not limited to this, and the distal end becomes narrower as shown in FIG. 10A. It may be. At this time, if the tip outer resin layer 51 is formed so as to be thinner toward the distal end, the tip 50 can be made more flexible toward the tip.

In the above-described embodiment, the tip portion 50 has the inner resin layer 11, the resin net 30, and the tip portion outer resin layer 51. However, as shown in FIG. A visible marker 80 may be provided on the inner peripheral side of the resin net 30. By providing it on the inner periphery of the resin net 30, the marker 80 is fixed to the resin net 30 even if any of the tip portions 50 is damaged, so that the marker 80 is prevented from falling off. can do.

In the above-described embodiment, the reinforcing metal wire 12 is not disposed at the tip 50, but a second reinforcing metal wire 12a may be provided as shown in FIG. 11A. The second reinforcing metal wire 12a is preferably wound in a coil shape from the viewpoint of flexibility. At this time, the second reinforcing metal wire 12a itself may function as a coil marker. Moreover, as shown to FIG. 11B, you may arrange | position so that the resin-made net | networks 30 may be pinched | interposed into the metal wire for reinforcement. By adopting such a configuration, it is possible to fix more strongly than a state where the resin is only coated.

Further, in the above-described embodiment, the resin net 30 is formed of a thread-shaped resin of about 1 μm to 100 μm formed into a cylindrical net shape by a net assembly, but the resin net 30 is formed into a net shape. The net 30 may be used, or a net-assembled one may be coated with an adhesive or heat-welded. By using the resin net 30 coated with an adhesive, the adhesion to the distal end outer resin layer 51 is further increased, and the resin net 30 can be more firmly fixed to the catheter 100. Moreover, since the tension | tensile_strength of the longitudinal direction of the resin net 30 etc. can be adjusted beforehand by welding with a heat | fever, the softness | flexibility etc. of the front-end | tip part 50 can be adjusted now.

(Example)
As a catheter according to the present invention, a catheter (Example) having a resin net made of a synthetic resin thread of 20 μm and a catheter (Comparative Example) not having a resin net are prepared, the tip is gripped, and a test speed is 100 mm. A tensile test was performed at a distance of 10 mm / min.
The test results are shown in FIG. In FIG. 12, the vertical axis indicates the tensile strength and the horizontal axis indicates the stroke. According to this result, the tensile strength at the tip is 1.75 N and the maximum displacement length is 3.05 mm without the resin net, and the tensile strength at the tip is 2.75 N with the resin net. The maximum displacement length was 3.14 mm. In the case of the resin net, it was broken at the gripping portion, and the resin net itself was not broken.

As shown in the embodiment described above, it can be used as a catheter.

DESCRIPTION OF SYMBOLS 10 ... Catheter main body, 11 ... Inner resin layer, 12 ... Reinforcing metal wire, 12a ... Reinforcing metal wire, 13 ... Outer resin layer, 19 ... Core lumen, 30 ... Resin net, 40 ... Middle part, 50 ... Tip portion 51... Tip portion outer resin layer, 51 a... Resin tube, 80 .. marker, 100 .. catheter, 110 .. catheter device, 130 .. catheter tube, 200.

Claims

A catheter body having an inner resin layer, a reinforcing metal wire disposed on the outer periphery of the inner resin layer, and an outer resin layer disposed on the outer periphery of the reinforcing metal wire;
Disposed on the distal end side of the catheter body, at least a part of the inner resin layer, the reinforcing metal wire disposed on the outer periphery of the inner resin layer, and the outer periphery of the reinforcing metal wire A middle portion having a resin net and a tip outer resin layer disposed on the outer periphery of the resin net;
Distal side of the intermediate portion, the inner resin layer, the resin net disposed on the outer periphery of the inner resin layer, and the tip outer resin layer disposed on the outer periphery of the resin net And a tip having
A catheter characterized by comprising.
The catheter according to claim 1, wherein the resin net is formed in a cylindrical shape.
Each metal wire of the reinforcing metal wire and each resin thread of the resin net are 45 ° to 89 ° with respect to the axial direction of the catheter body, and the angle difference between them is within 10 °. The catheter according to claim 1 or 2, wherein the catheter is characterized.
The catheter according to any one of claims 1 to 3, further comprising the reinforcing metal wire on an outer periphery of the resin net.
The catheter according to any one of claims 1 to 4, wherein the distal end portion is provided with an X-ray marker on an inner peripheral side of the resin net.
The catheter according to any one of claims 1 to 5, wherein the distal end portion includes a second reinforcing metal wire on an inner peripheral side of the resin net.
The catheter according to claim 6, wherein the second reinforcing metal wire is a coil marker.