JPH09322940A - Catheter tube and balloon catheter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a catheter tube which does not flaw the vital vascular wall, easily transmits the operating force at a proximal end to a distal end and facilitates the insertion to the vital vascular cavity and provide a balloon catheter. SOLUTION: This tube is a two-layered tube having a lumen communicating from the distal end to the proximal end and consisting of an inside layer 10 and outside layer 11. The thickness of the inside layer 10 and the thickness of the outside layer 11 (the parts excluding projecting parts) are approximately constant from the distal end to the proximal end. The inside layer 10 is formed of a rigid material and the outside layer 11 of a soft material. The inside layer 10 and the outside layer 11 and laminated in tight contact with each other and are provided with plural projections of the same material as the material of the inner layer 10 outward in a radial direction. The projections are embedded into the outside layer 11 and the bending rigidity thereof is made low at the distal end and made high at the proximal end.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a catheter tube and a balloon catheter obtained by using this catheter tube. More specifically, the operating force at the proximal end portion does not damage the wall of a living body tube and the distal end has a distal end. Easy to reach
The present invention also relates to a catheter tube that can be easily inserted into a living body lumen and a balloon catheter obtained by using the catheter tube.

[0002]

2. Description of the Related Art A catheter is inserted into a living body lumen such as a blood vessel, and while controlling the direction of the distal end thereof, it reaches a target site, and through this catheter, treatment inside the living body lumen is performed. . The catheter has a certain degree of hardness, that is, a relatively small degree, in the catheter tube that is the catheter body, in order to facilitate insertion into the body lumen and transfer of the operation force at the catheter proximal end to the distal end. It is required to have flexibility. On the other hand, since the catheter tube is inserted into a blood vessel that plays an important role in the living body, the catheter tube is soft to a certain extent and relatively large in order to prevent the blood vessel and the like from being pierced by the catheter during the insertion. It is required to have flexibility. To meet these conflicting requirements, the distal end is made of a relatively large flexible material (soft material) and the proximal end is made of a relatively small flexible material (hard material). Catheter tubes have been proposed. However, since the soft material (distal end portion) and the hard material (proximal end portion) are simply joined together, the seam catches on the living body lumen and damages the living body lumen wall, or the living body lumen. It could interfere with insertion into the cavity. As another catheter tube, a two-layer tube in which an inner layer tube made of a hard material and an outer layer tube made of a soft material are laminated, and the wall thickness of the inner layer tube is thinner than that of the outer layer tube at the distal end side, A catheter tube (Japanese Patent Laid-Open No. 60-31765) is proposed in which the wall thickness of the inner layer tube is thicker than that of the outer layer tube on the proximal end side. However, in this catheter tube, the inner layer tube and the outer layer tube may be separated. A crack may occur from this peeled portion.

[0003]

DISCLOSURE OF THE INVENTION The object of the present invention is not to damage the living body canal wall, to easily transmit the operating force at the proximal end to the distal end, and to easily insert the living body lumen into the living body lumen. To provide a simple catheter tube and balloon catheter. As a result of earnest research to achieve this object, the present inventors have laminated an outer layer and an inner layer in the radial direction of a pipe wall, provided a protrusion on the inner layer or the outer layer, and embedded the protrusion in the outer layer or the inner layer. It was found that the above object can be achieved by using a tube, and the present invention has been completed based on this finding.

[0004]

Thus, according to the present invention, (1) it has a lumen communicating from one end to the other end, and the pipe wall is formed by laminating inner and outer layers in a radial direction, A catheter tube in which one of the inner layer and the outer layer is embedded in the other layer and has a plurality of convex projections, and the height of the projections is higher at the other end than at the one end. Will be provided.

The following are provided as preferred embodiments of the catheter tube of the present invention. (2) The catheter tube according to (1), wherein the inner layer is made of a hard material and the outer layer is made of a soft material. (3) The catheter tube according to (1), wherein the inner layer is made of a soft material and the outer layer is made of a hard material. (4) The catheter tube according to (1) above, wherein the projections are arranged so as to be symmetrical with respect to the major axis of the catheter tube.

Further, according to the present invention, the above (1) to (4)
There is provided a balloon catheter characterized in that a balloon formed of a thin film is provided at one end of any one of the catheter tubes.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the catheter tube and balloon catheter according to the present invention will be described below.
This will be described in detail with reference to the drawings.

FIG. 1 is an axial sectional view showing an embodiment of the catheter tube of the present invention, FIG. 2 (a) is a sectional view taken along the line AA 'of the catheter tube shown in FIG. 1, and FIG. 2 (b) is shown in FIG. FIG. 4 is a cross-sectional view of the catheter tube taken along the line BB ′ and FIG. 2C is a cross-sectional view taken along the line CC ′ of the catheter tube shown in FIG. 1, and FIG. 3A is a cross section taken along the line AA ′ of the catheter tube shown in FIG. 3, FIG. 4B is a cross section taken along the line BB ′ of the catheter tube shown in FIG. 3, and FIG. It is a figure which shows each -C 'cross section. 5 (a) is an axial cross-sectional view showing a balloon catheter obtained by using the catheter tube having the structure shown in FIG. 1, and FIG. 5 (b) is an AA of the balloon catheter shown in FIG. 5 (a). 5'is a cross section, FIG. 5 (c) is a BB 'cross section of the balloon catheter shown in FIG. 5 (a), and FIG. 5 (d) is a CC' cross section of the balloon catheter shown in FIG. 5 (a). Is.

[First Embodiment] A catheter tube 1 shown in FIG. 1 is a double-layer tube having a lumen communicating from the distal end to the proximal end and comprising an inner layer 10 and an outer layer 11. The tube usually has an outer diameter of 0.5 to 5 mm and a wall thickness of 0.05 to 1 mm. The thickness of the inner layer and the thickness of the outer layer (portions excluding the protrusions) are substantially constant from the distal end to the proximal end. The thickness ratio of the inner layer and the outer layer (inner layer thickness / outer layer thickness) is usually 5/95 to 95/5.

The catheter tube has an inner layer made of a hard material and an outer layer made of a soft material, and the inner layer and the outer layer are laminated in close contact with each other. The soft material and the hard material forming the tube are polyethylene, polypropylene, polyethylene terephthalate, polyvinyl chloride, ethylene-vinyl acetate copolymer, polyurethane, polyamide, polyimide,
It is appropriately selected from fluoropolymers, silicones and the like, polyamide elastomers such as polyamide-polyether block copolymers and the like. As a soft material,
Shore hardness of 60D or less, preferably 20D to 50D is used. As the hard material, one having a Shore hardness of 40D to 90D, preferably 50D to 80D is usually used. The difference in Shore hardness between hard and soft materials is
Shore D display, usually 10D-60D, preferably 2
It is 0D to 50D.

The catheter tube 1 is provided with a plurality of protrusions made of the same material as the inner layer toward the outer side in the radial direction, and the protrusions are embedded in the outer layer. The number of protrusions is not particularly limited. Usually, it is 2 to 30, preferably 2 to 8. The protrusions are preferably arranged symmetrically to the long axis of the catheter tube.

The height of the protrusion is higher at the proximal end (FIG. 2 (c)) than at the distal end (FIG. 2 (a)). By changing the height of the protrusion, the bending rigidity, softness, etc. of the catheter tube can be changed for each part.
In this embodiment, the bending stiffness of the catheter tube is low at the distal end and high at the proximal end. Since the distal end portion has a low bending rigidity, it is less likely to damage the living body canal wall even if it collides with the wall. Since the proximal end portion has high bending rigidity, the operating force is easily transmitted to the other end, and the proximal end portion can be inserted without buckling or bending, so that the proximal end portion can be easily inserted into the living body lumen.

In this embodiment, the height of the protrusion changes continuously with respect to the axial direction, but it may change stepwise.

[Embodiment 2] A catheter tube 101 shown in FIG. 3 has a laminated structure composed of an inner layer 110 and an outer layer 111. When the outer layer is provided with a plurality of protrusions radially inward, the protrusions are formed. It is embedded in the inner layer. Others are the same as those in the first embodiment, and thus the description thereof will be omitted.

In the first and second embodiments, the outer layer is made of a soft material and the inner layer is made of a hard material. However, the outer layer may be made of a hard material and the inner layer may be made of a soft material. Further, a coating layer for reducing friction can be provided inside or outside the inner layer and the outer layer. Examples of the coating layer for reducing friction include a layer of a wettable polymer such as polyvinylpyrrolidone, polyacrylamide, polymethacrylamide, polyacrylic acid and polymethacrylic acid, and a layer of a lubricating oil such as silicone oil.

[Embodiment 3] The lumen of the catheter tube (outer tube) having the structure shown in FIG. 1 has the structure shown in FIG. 3 and an outer diameter smaller than the inner diameter of the outer tube (hereinafter referred to as an inner tube). ) Was inserted, and a part of the outer surface of the inner tube was fixed so as to contact with a part of the inner surface of the outer tube so that the inner tube distal end extended from the outer tube distal end in the distal direction. Next, a cylindrical thin film made of polyamide or polyurethane is covered on the portion where the inner tube extends from the outer tube, one end of the thin film is at the distal end of the inner tube, and the other end of the thin film is at the distal end of the outer tube. It was fixed at the end and a balloon was formed. A Y-shaped branch pipe connector was joined to the proximal ends of the outer tube and the inner tube to obtain a balloon catheter as shown in FIG. The balloon catheter had a distal end that was soft and relatively flexible, and a proximal end that was hard and relatively flexible. When I tried to insert this balloon catheter into the aorta of a goat, it was easy to insert, and the operation force at the proximal end was sufficiently transmitted to the distal end. It was found that treatments such as PTCA) can be performed easily.

In this embodiment, the catheter tube of the present invention is used as the outer tube and the inner tube, but it is also possible to form only the outer tube or the inner tube with the catheter tube of the present invention.

Further, in the third embodiment, the balloon is attached to the end of the double pipe, but the balloon can be attached to the end of the single pipe consisting of one catheter tube of the present invention.

[0019]

Since the catheter tube of the present invention can have a large difference in flexibility between the distal end portion and the proximal end portion, both flexibility on the distal end side and rigidity on the proximal end side can be achieved. Since the catheter tube is inserted into the body lumen, the wall of the body tube is less likely to be damaged even when the catheter tube is inserted into the body lumen, and the operation force of the proximal end portion is easily transmitted to the distal end portion. Easy to insert into. Further, peeling of the laminated surface is less likely to occur, and thus cracking due to bending force is less likely to occur. Further, since the balloon catheter obtained by using the catheter tube according to the present invention also has the above-mentioned characteristics of the catheter tube, it greatly improves the operability of medical treatment.

[Brief description of drawings]

FIG. 1 is a view showing an embodiment of a catheter tube of the present invention.

2 is a cross section taken along the line AA '(a), a line BB' (b) and a line CC '(c) of the catheter tube shown in FIG.
FIG.

FIG. 3 is a view showing another embodiment of the catheter tube of the present invention.

4 is a sectional view taken along the line AA ′ (a), a sectional view taken along the line BB ′ of FIG. 3 and a sectional view taken along the line CC ′ of the catheter tube shown in FIG.
FIG.

FIG. 5 is a diagram showing an embodiment of a balloon catheter using the catheter tube according to the present invention.

[Explanation of symbols]

 1, 101 ... Catheter tube 10, 110 ... Inner layer 11, 111 ... Outer layer 4 and 104 ... Balloon catheter 5 and 105 ... Balloon 7 ... Inner tube 8 ... Outer tube

Claims (2)

[Claims] 1. A tube wall having a lumen communicating from one end to the other end, wherein the tube wall is formed by laminating an inner layer and an outer layer in a radial direction, and is embedded in either the inner layer or the outer layer in the other layer. A catheter tube in which a plurality of convex projections are formed, and the height of the projections is higher at the other end than at the other end. 2. A balloon catheter, wherein a balloon formed of a thin film is provided at one end of the catheter tube according to claim 1.