JP4744005B2 - catheter - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention, for example, expands a stenosis part to improve a blood flow at the peripheral side of the stenosis part in order to treat a diagnosis tool or a treatment tool for performing various treatments in a blood vessel, and further treats an intravascular stenosis part. The present invention relates to a dilatation catheter for illustration.
[0002]
[Prior art]
With the rise of microcatheters, it has become possible to perform treatment and diagnosis in microvessels or vessels that have been impossible with conventional catheters. Examples of the microcatheter include a percutaneous transluminal coronary angioplasty catheter (hereinafter, dilatation catheter) used for myocardial infarction or angina. During this angioplasty procedure, it is often necessary to change the catheter. For example, replacement is necessary when changing the balloon size, diagnosing the vicinity of the stenosis, changing the treatment tool, or the like. One method of exchanging is to use a long guidewire for replacement, but the operation of the long wire is time consuming and further requires two or more surgeons, which is difficult to handle. In order to cope with this, a “rapid exchange” type catheter is used, in which only the distal portion of the catheter follows the guide wire.
[0003]
[Problems to be solved by the invention]
A known rapid exchange type catheter has a base shaft including a flow path for an expansion fluid for inflating and deflating a balloon therein, and a highly flexible distal shaft including a flow path communicating with the flow path of the base shaft And an inflatable / deflatable balloon attached to the tip of the tip shaft, and a guide wire lumen for inserting the guide wire.
[0004]
The base shaft is required to be highly rigid so that the pushing force applied to the hand when the catheter is operated is more directly transmitted to the distal end portion of the catheter.
In recent years, for example, as described in JP-A-6-506124, a rapid exchange type catheter using a high-strength metal tube for the base shaft has been seen.
[0005]
However, this metal tube has the advantage of being able to secure a wide flow path through which the expansion fluid passes because it is highly rigid and can be formed thin and thin. On the other hand, it is easy to bend and bend. If you try to restore the (kinked) part, this part may break.
[0006]
Further, if a catheter is configured by connecting a highly rigid base shaft and a flexible distal shaft as they are, the rigidity of the catheter changes abruptly between these shafts. When such a sudden change in rigidity exists, the catheter bends rapidly when passing through a tortuous blood vessel in the middle of being introduced to a target site in the living body, and stress is concentrated on the suddenly changed portion of the rigidity, which is extremely high. There is a problem that bending (kink) occurs with probability.
[0007]
An object of the present invention is to provide a dilatation catheter and a catheter that are provided with a base shaft made of a metal tube and that have no fear of bending (kinks) and have excellent kink resistance. Another object of the present invention is to provide a catheter that can alleviate a sudden change in rigidity between a rigid base shaft and a flexible distal shaft, and has excellent kink resistance over its entire length.
[0008]
[Means for Solving the Problems]
The dilatation catheter of the present invention includes a base shaft made of a metal tube, a tip shaft provided on the distal end side of the base shaft and having lower rigidity than the base shaft, and a position between the base shaft and the tip shaft. And in fluid communication with the base shaft A tube-shaped intermediate portion, a hub attached near the proximal end of the base shaft and capable of attaching a pressure applying device, a balloon attached near the distal end of the distal shaft, to which pressure is applied from the hub, and A dilatation catheter having a distal opening on the distal side of the balloon and a proximal opening on the proximal side of the balloon, and a guide wire lumen through which the guide wire is inserted, Provided in the base end of the shaft, and provided with a reinforcing body attached to the base shaft or the hub The outer diameter of the reinforcing body is smaller than the inner diameter of the base shaft, and the distal end of the reinforcing body is located closer to the proximal end than the distal end of the base shaft. It is characterized by.
[0010]
According to the present invention, kink resistance is imparted to the base shaft by providing the reinforcing body in the base end portion of the base shaft made of the metal tube. As a result, the base shaft of the metal tube is hardly bent (kinked), and even if the base shaft is kinked, it does not reach breakage.
[0011]
The distal end portion of the base shaft preferably has a lower rigidity than the proximal end portion of the base shaft. Furthermore, it is more preferable that the rigidity of the base shaft intrusion portion is gradually changed by decreasing the rigidity of the distal end portion of the base shaft on the distal end side of the distal end portion and increasing the rigidity on the proximal end side of the distal end portion.
[0012]
The distal end portion of the base shaft preferably has a spiral slit. Further, it is more preferable that the pitch of the spiral slit is shortened at the distal end side of the slit and is increased at the proximal end side so that the rigidity of the base shaft intrusion portion changes gently.
[0013]
It is preferable that the distal end of the reinforcing body is positioned closer to the proximal end side than the distal end of the base shaft to ensure a wide inflation lumen. In particular, the rigidity of the distal end portion of the base shaft is made lower than the proximal end portion of the base shaft, and the distal end of the reinforcing body is positioned closer to the proximal end than the distal end of the base shaft, thereby reinforcing the flexibility of the distal end portion of the base shaft. Without being obstructed by the body, the rigidity of the shaft constituting the catheter can be gradually changed from the proximal end side to the distal end side, and the kink resistance can be improved over the entire length of the catheter.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the dilatation catheter of the present invention will be described with reference to the drawings.
[0015]
FIG. 1 is an external view of an embodiment of the dilatation catheter of the present invention. FIG. 2 is an external view showing a main component member in an enlarged view, with a part of the dilatation catheter of FIG. 1 broken and a part of the base shaft omitted. FIG. 3 is an external view showing the base shaft. FIG. 4 is a cross-sectional view showing the intermediate portion, the distal end portion of the base shaft, and the proximal end portion of the distal shaft. FIG. 5 is a cross-sectional view showing the base end of the base shaft and the hub.
[0016]
As shown in FIGS. 1 and 2, the dilatation catheter 1 is a so-called rapid exchange type catheter, and is inserted into the blood vessel along the guide wire 2. The dilatation catheter 1 includes a hub 16, a base shaft 15, an intermediate portion 14, a distal end shaft 13, a balloon 12, an inner tube shaft 11, and a reinforcing body 155 (see FIG. 5) described later.
[0017]
The hub 16 on the proximal end side is formed with a luer taper so that it can be connected to a pressure applying device such as an inflator. A rigid base shaft 15 made of a metal pipe (metal pipe) is joined to the hub 16 so as to allow fluid communication. The base shaft 15 is provided with a depth marker 151 so that it can be easily confirmed how deep the dilatation catheter 1 is inserted into a guiding catheter (not shown) during angioplasty. Further, on the outer surface of the base shaft 15 on the distal end side of the hub 16, a kink protector 161 for preventing bending (kinking) at a boundary portion between the hub 16 and the base shaft 15 is installed. As will be described in detail later, the distal end portion of the base shaft 15 is a base shaft intrusion portion 152.
[0018]
A tube-shaped intermediate portion 14 is provided on the distal end side of the base shaft 15 so as to be in fluid communication. A distal end shaft 13 made of a material such as resin is provided at the distal end side of the intermediate portion 14 so as to be in fluid communication. A proximal end portion of the balloon 12 is provided on the distal end side of the distal shaft 13 so as to be in fluid communication.
[0019]
The inner tube shaft 11 passes through the tip shaft 13 and the balloon 12, and a gap (lumen) communicating with the inside of the balloon 13 is formed between the inner surface of the tip shaft 13 and the outer surface of the inner tube shaft 11. ing. In the illustrated structure, the inner tube shaft 11 is coaxially disposed with respect to the tip shaft 13, and an annular gap is formed therebetween. However, in the present invention, the inner tube shaft 11 may be disposed at a position that is eccentric with respect to the central axis of the tip shaft 13 over substantially the entire length.
[0020]
The distal end portion of the inner tube shaft 11 is a distal tip 111, the distal tip 111 extends from the distal end of the balloon 12, and the distal tip 111 is joined to the distal end side of the balloon 12 in a liquid-tight state. Yes. On the other hand, the proximal end of the inner tube shaft 11 is extended to a guide wire opening 141 provided in a part from the intermediate portion 14 to the distal shaft 13 and is joined in a liquid-tight state. The guide wire 2 shown in FIG. 1 is inserted into the inner tube shaft 11 with the distal end opening of the distal end tip 111 as an inlet and the guide wire opening 141 as an outlet. A contrast marker 121 is provided around the inner tube shaft 11 inside the balloon 12.
[0021]
When the balloon 12 is not expanded, the balloon 12 is folded around the outer periphery of the inner tube shaft 11. When the balloon 12 is in an expanded state, the central portion is substantially cylindrical, and the narrowed portion of the blood vessel can be easily expanded. Note that the central portion of the balloon 12 does not need to be a complete cylinder, and may be a polygonal column. Further, the contrast marker 121 is provided in order to facilitate positioning of the balloon 12 to the stenosis site under fluoroscopy during angioplasty.
[0022]
In the dilatation catheter 1 having the above-described configuration, when pressure is applied by a pressure application device (not shown) attached to the hub 16, the pressure medium is transmitted from the hub 16 to the base shaft 15, the base shaft intrusion portion 152, the intermediate portion 14, The balloon 12 can be expanded by reaching the balloon 12 through the gap between the tip shaft 13 and the inner tube shaft 11. Needless to say, the base shaft 15, the intermediate portion 14, the tip shaft 13, the inner tube shaft 11, and each joint portion have pressure resistance performance higher than the pressure at which the balloon 12 bursts.
[0023]
The structure of the base shaft 15 will be described in more detail with reference to FIG. As shown in FIG. 3, the base shaft 15 includes a main shaft portion 153 and a base shaft intrusion portion 152 formed by subjecting the distal end portion of the main shaft portion 153 to spiral slit processing. Accordingly, the intrusion portion (the distal end portion of the base shaft 15) 152 has lower rigidity (bending rigidity) than the base end portion of the base shaft 15.
[0024]
In FIG. 3, the pitch of the spiral slit is short on the tip end side of the slit and is long on the base end side, and the pitch gradually decreases toward the tip in the portion between these. Thereby, the pitch of the slit becomes narrower toward the tip. The base shaft intrusion portion 152 is formed by laser processing the distal end portion of the main shaft portion 153. In addition to the above-described configuration, the pitch of the slit is narrowed toward the tip, for example, the pitch is narrowed continuously or stepwise from the base to the tip of the slit toward the tip. It may be.
[0025]
Further, in the present invention, instead of the spiral slit, only the intrusion portion 152 (the tip portion of the base shaft 15) has a lower rigidity than the other portions by other methods such as thermal processing or providing a large number of pores. (Flexibly) may be formed.
[0026]
Referring to FIG. 4, the structure of the distal end portion of the base shaft 15 and the proximal end portion of the distal shaft 13 with the intermediate portion 14 as the center is shown. As shown in FIG. 4, the base shaft intrusion portion 152 at the distal end portion of the base shaft 15 is disposed so as to extend into the intermediate portion 14, and is extended to the guide wire opening 141 provided in the intermediate portion 14. Yes. Specifically, the proximal end portion of the inner tube shaft 11 is fixed to a part of the intermediate portion 14 in the outer circumferential direction, and the proximal end opening of the inner tube shaft 11 is exposed to the outside of the intermediate portion 14 to guide the guide. A wire opening 141 is formed. The guide wire opening 141 may be provided in the base shaft 15 or the tip shaft 13, or may be provided in a boundary portion (joint portion) between the intermediate portion 14 and the tip shaft 13.
[0027]
By disposing the base shaft intrusion portion 152 inside the intermediate portion 14 in this way, the intermediate portion 14 has lower rigidity (softer) than the main shaft portion 153 and higher rigidity (harder) than the tip shaft 13. Can do. Thus, the rigidity of the shaft constituting the dilatation catheter 1 can be gradually changed from the proximal end side to the distal end side, and even when the intermediate portion 14 is bent suddenly, the stress is not concentrated at one place, and the kink Generation can be reduced.
[0028]
As described above, the base shaft that plays the role of kink prevention by subjecting the vicinity of the distal end of the base shaft 15 (main shaft portion 153) of the dilatation catheter 1 to spiral slit processing using a commonly performed technique such as laser processing. An intrusion portion 152 is formed. Thus, the base shaft intrusion portion 152 integrated with the main shaft portion 153 can be formed by a simple process, and the catheter can be assembled by a relatively simplified process. Further, by disposing the base shaft intrusion portion 152 inside the intermediate portion 14, even when the intermediate portion 14 is bent sharply, the stress is not concentrated on one place, and the occurrence of kinks can be effectively reduced. In addition, by forming the pitch of the spiral slit short on the distal end side and longer on the proximal end side, the rigidity of the entire shaft can be gradually changed, and the occurrence of kinks can be reduced more effectively.
[0029]
And in this invention, as shown in FIG. 5, the reinforcement body 155 is installed in the base end part of the base shaft 15. As shown in FIG. Accordingly, kink resistance is imparted to the base shaft 15 made of a metal tube, and the base shaft 15 is not easily bent (kinked). In addition, even when the base shaft 15 is bent at a steep angle by an external force and is bent (kink), the base shaft 15 is not broken and the safety of the catheter 1 is improved.
[0030]
The reinforcing body 155 is a long wire, and has an outer diameter smaller than the inner diameter of the inflation lumen 154 so as not to obstruct the flow path of the inflation lumen 154 of the base shaft 15. In addition, you may adjust the rigidity of the reinforcement body 155 suitably by heat-processing the reinforcement body 155 as needed.
[0031]
In FIG. 5, the base end portion of the reinforcing body 155 is attached to the inner surface of the base shaft 15 by welding at a welded portion 153. Thereby, the reinforcing body 155 is fixed in the base shaft 15. Instead of the above welding, the reinforcing body 155 may be attached to the base shaft 15 by, for example, bonding with an adhesive.
[0032]
The distal end of the reinforcing body 155 is preferably positioned closer to the proximal end than the distal end of the base shaft 15. As a result, a portion where the reinforcing body 155 is not installed is formed on the distal end side of the base shaft 15, the flow path of the inflation lumen 154 is widened, and the pressure medium injected from the hub 16 can flow smoothly. In general, the above-described bending (kinking) of the base shaft 15 often occurs at the proximal portion of the catheter, that is, the proximal end portion of the base shaft 15. By installing the reinforcing body 155 at this portion, the kink resistance can be effectively increased. Sex can be imparted. Particularly in the case of dilatation catheters, the distal end of the base shaft 15 is located in a guiding catheter (not shown) during catheter operation and is reinforced to some extent by the guiding catheter, so that the base exposed from the proximal end of the guiding catheter By installing the reinforcing body 155 at the base end portion of the shaft 15, kink resistance can be effectively imparted.
[0033]
Further, as described above, the rigidity of the base shaft intrusion portion 152 (the distal end portion of the base shaft 15) is formed lower (softer) than the other portions, and the distal end of the reinforcing body 155 is proximal to the distal end of the base shaft 15 By positioning at the proximal end side, more preferably at the proximal end side relative to the intrusion portion 152, the flexibility of the base shaft intrusion portion 152 (the distal end portion of the base shaft 15) is not hindered by the reinforcing body 155, and the dilatation catheter 1 can be gradually changed from the proximal end side to the distal end side. Thereby, even when the intermediate portion 14 is bent sharply, the stress is not concentrated at one place, and the generation of kinks can be reduced.
[0034]
An annular space between the outer surface of the base shaft 15 and the inner surface of the hub 16 is filled with an adhesive 162. Thereby, the base shaft 15 is fixed in the hub 16 via the adhesive 162.
[0035]
Next, the material and dimensions of each member constituting the dilatation catheter of the present invention will be described in more detail.
[0036]
The base shaft 15 is made of, for example, a metal such as a Ni—Ti alloy, brass, stainless steel (SUS), or aluminum.
[0037]
The main shaft portion 153 of the base shaft 15 has an outer diameter of about 0.3 mm to 3 mm, preferably 0.5 mm to 1.5 mm, a thickness of about 10 to 150 μm, preferably 20 to 100 μm, and a length of 300 mm to 2000 mm. The tube is preferably 700 mm to 1500 mm.
[0038]
The base shaft intrusion portion 152 of the base shaft 15 has an outer diameter of about 0.3 mm to 3 mm, preferably 0.5 to 1.5 mm, a wall thickness of 10 to 150 μm, preferably 20 to 100 μm, and a length of 30 to 200 mm. The thickness is preferably 50 to 180 mm.
[0039]
In the case where the pitch of the spiral slit in the base shaft intrusion portion is short on the distal end side as in the example shown in the drawing and is longer on the proximal end side, it is 0.1 to 10 mm on the distal end side, preferably 0.3 to 2 mm) and 1 to 20 mm, preferably 2 to 10 mm on the base end side. Moreover, the width | variety of a spiral slit is 1 mm or less, Preferably it is about 0.01-0.5 mm.
[0040]
The material of the reinforcing body 155 is preferably a metal such as a superelastic alloy such as a Ni—Ti alloy, brass, stainless steel (SUS), or aluminum. In addition, as long as the material has relatively high rigidity, a resin such as polyimide, vinyl chloride, or polycarbonate may be used.
[0041]
From the viewpoint of securing the inflation lumen 154, the outer diameter of the reinforcing body 155 needs to be set smaller than the inner diameter of the base shaft 15 (the inner diameter of the inflation lumen 154), and is about 0.1 to 2.0 mm, preferably 0. About 1 to 1.2 mm. The length of the reinforcing body 155 is preferably shorter than the base shaft 15 from the viewpoint of positioning the distal end of the reinforcing body 155 closer to the proximal end side than the distal end of the base shaft 15 as described above, preferably about 100 to 1500 mm. Is about 200 to 700 mm.
[0042]
Examples of the material constituting the tip shaft 13 and the intermediate portion 14 include polyolefin (for example, polyethylene, polypropylene, polybutene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, ionomer, or a mixture of two or more of these) ), Cross-linked polyolefin, polymer materials such as polyvinyl chloride, polyamide, polyamide elastomer, polyester, polyester elastomer, polyurethane, polyurethane elastomer, fluororesin, polyimide, or a mixture thereof can be used.
[0043]
The tip shaft 13 and the intermediate portion 14 have an outer diameter of 0.5 to 1.5 mm, more preferably 0.7 to 1.1 mm, a wall thickness of 25 to 200 μm, more preferably 50 to 100 μm, and a length of 300 to 300 mm. The tube is 2000 mm, more preferably 300 to 1500 mm.
[0044]
The tip shaft 13 and the intermediate portion 14 may be formed of the same tube, or may be configured by separately preparing a tube for the tip shaft and a tube for the intermediate portion and connecting them appropriately.
[0045]
As a material constituting the inner tube shaft 11, a material having some flexibility is used. For example, polyolefin (for example, polyethylene, polypropylene, polybutene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, ionomer, or a mixture of two or more thereof), cross-linked polyolefin, polyvinyl chloride, polyamide, polyamide Polymer materials such as elastomers, polyesters, polyester elastomers, polyurethanes, polyurethane elastomers, polyimides, fluororesins, and mixtures thereof can be used.
[0046]
The inner tube shaft 11 has an outer diameter of about 0.1 to 1.0 mm, preferably 0.3 to 0.7 mm, a thickness of about 10 to 150 μm, preferably 20 to 100 μm, and a length of 100 to 2000 mm, preferably Is a tube of 200-1500 mm.
[0047]
The material of the balloon 12 is preferably a material having a certain degree of plasticity so that the stenosis of the blood vessel can be expanded. For example, polyolefin (for example, polyethylene, polypropylene, polybutene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, ionomer, etc.), cross-linked polyolefin, polyester (for example, polyethylene terephthalate, etc.), polyester elastomer, polyvinyl chloride , Polyurethane, polyurethane elastomer, polyphenylene sulfide, polyamide (for example, nylon 11 and nylon 12), polyamide elastomer (for example, polyether ester amide), polymer materials such as fluororesin, silicone rubber, latex rubber, etc. Can do. Moreover, what blended these polymeric materials suitably, and the laminated | multilayer film which laminated | stacked these polymeric materials suitably can also be used. It is good also as a structure which attached the balloon 12 formed by the biaxial stretch blow molding method etc. to the front end side of the front end shaft 13, and formed the balloon 12 integrally by giving stretch blow molding etc. to the front-end | tip part of the front end shaft 13. Also good.
[0048]
The balloon 12 has an outer diameter of 1.0 to 10 mm, preferably 1.0 to 5.0 mm, and a length of 5 to 50 mm, preferably 10 to 40 mm when expanded. Is 10 to 70 mm, preferably 15 to 60 mm.
[0049]
The contrast marker 12 is preferably formed by a coil spring or a ring, and one or more contrast markers can be provided. As the material of the contrast marker 12, it is preferable to use a material having high X-ray contrast properties, such as Pt, Pt alloy, W, W alloy, Au, Au alloy, Ir, Ir alloy, Ag, Ag alloy.
[0050]
As a material of the hub 16, for example, a thermoplastic resin such as polycarbonate, polyamide, polysulfone, polyarylate, methacrylate-butylene-styrene copolymer, or the like can be used.
[0051]
Examples of the material of the kink protector 161 include polyolefin (for example, polyethylene, polypropylene, polybutene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, ionomer, etc.), crosslinked polyolefin, and polyester (for example, polyethylene terephthalate). , Polyester elastomer, polyvinyl chloride, polyurethane, polyurethane elastomer, polyamide, polyamide elastomer, styrene-ethylene-butylene-styrene block copolymer (SEBS), polymer materials such as fluororesin, silicone rubber, latex rubber, etc. Can do.
[0052]
As mentioned above, although this invention was demonstrated based on the rapid exchange type catheter which has the guide wire opening part 141 in the position spaced apart from the base end part of the catheter to the front-end | tip part, this invention is not limited to this, A guide wire opening part May be a type of catheter formed at the proximal end (hub) of the catheter.
[0053]
Further, in the above example, the catheter has a guide wire lumen formed inside the inner tube shaft disposed in the tip shaft. However, the present invention is not limited to this, and the inside of one tube (shaft). Alternatively, a guide wire lumen and a balloon inflation lumen may be formed in parallel.
[0054]
FIG. 6 is a view showing another embodiment of the present invention. In the embodiment shown in FIGS. 1 to 5 and described above, the reinforcing body 155 is attached to the base shaft 5, whereas in this embodiment, the reinforcing body 155 is attached to the hub 16. Is the same as the above-described embodiment.
[0055]
The base end portion of the reinforcing body 155 shown in FIG. 6 is bent in a U shape, and the bent portion is inserted between the outer surface of the hub 16 and the inner surface of the base shaft 15, and the hub 16 and the base shaft are inserted. 15 is fixed between them by an adhesive 162 filled in an annular space between them. Thereby, both the reinforcing body 155 and the base shaft 15 are fixed to the hub 16 via the adhesive 162.
[0056]
【The invention's effect】
As described above in detail, according to the present invention, it is possible to provide a catheter in which the kink resistance of the base shaft is improved by installing the reinforcing body in the base shaft made of a metal tube. Further, by positioning the distal end of the reinforcing body closer to the proximal end side than the distal end of the base shaft, it is possible to reliably prevent the occurrence of kinks at the base end portion of the base shaft, and to ensure a wide inflation lumen and expand the balloon. Therefore, the pressure fluid can be made to flow smoothly. Furthermore, if the rigidity of the distal end of the base shaft is made lower than that of other parts and the distal end of the reinforcing body is positioned closer to the proximal end than the distal end of the base shaft, the flexibility of the distal end of the base shaft is hindered. Therefore, the rigidity can be changed gently over the entire shaft, and the occurrence of kinks can be prevented more effectively.
[Brief description of the drawings]
FIG. 1 is a view showing a dilatation catheter according to an embodiment of the present invention.
FIG. 2 is an enlarged view showing main constituent members of the dilatation catheter of FIG.
3 shows the base shaft of the dilatation catheter of FIG.
4 is a cross-sectional view showing an intermediate portion of the dilatation catheter of FIG. 1, a distal end portion of a base shaft, and a proximal end portion of the distal shaft.
FIG. 5 is a cross-sectional view showing the base shaft and hub of the dilatation catheter of FIG.
FIG. 6 is an enlarged view showing main constituent members of a dilatation catheter according to another embodiment of the present invention.
[Explanation of symbols]
1 ... Dilatation catheter
2 ... Guide wire
11 ... Inner tube shaft
111 ... Tip
12 ... Balloon
121 ... Contrast marker
13 ... Tip shaft
14 ... Middle part
141 ... guide wire opening
15 ... Base shaft
151 ... Depth marker
152 ... Base shaft entry portion
153 ... Main shaft
155 ... Reinforcing body
16 ... Hub
17 ... Reinforcing wire

Claims (6)

A base shaft made of a metal tube, a tip shaft provided on the tip side from the base shaft, having a rigidity lower than that of the base shaft, located between the base shaft and the tip shaft, and in fluid communication with the base shaft A tube-shaped intermediate portion, a hub attached near the proximal end of the base shaft and capable of attaching a pressure applying device, a balloon attached near the distal end of the distal shaft and to which pressure is applied from the hub; A dilatation catheter having a distal opening on the distal side of the balloon and a proximal opening on the proximal side of the balloon, and a guide wire lumen through which the guide wire is inserted,
Provided in a base end portion of the base shaft, comprising a reinforcing body attached to the base shaft or the hub ;
The outer diameter of the reinforcing body is smaller than the inner diameter of the base shaft,
The dilatation catheter, wherein a distal end of the reinforcing body is located on a proximal end side with respect to a distal end of the base shaft .   The dilatation catheter according to claim 1, wherein the distal end portion of the base shaft has lower rigidity than the proximal end portion of the base shaft.   The dilatation catheter according to claim 2, wherein the rigidity of the distal end portion of the base shaft is small on the distal end side of the distal end portion and is increased on the proximal end side of the distal end portion.   The dilatation catheter according to claim 2, wherein the distal end portion has a spiral slit.   The dilatation catheter according to claim 4, wherein the pitch of the spiral slit is short on the distal end side and longer on the proximal end side. The dilatation catheter according to claim 4, wherein the pitch of the spiral slit is short on the distal end side and longer on the proximal end side. Wherein the tip further comprises an inner tube shaft provided inside the shaft, the lumen of the inner tube shaft according to any one of 5 claims 1, characterized in that to form a lumen for the guide wire Dilatation catheter.

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