JPH07136283A - Expansion catheter - Google Patents

Abstract

PURPOSE:To provide the expansion catheter capable of exhibiting a physical expansion function by a catheter with an expander and having a liquid chemical dosing function in combination by providing the catheter with the shrinkable or foldable expander and a liquid chemical permeable film body to cover the outer side thereof and permeating the chemical via this film body simultaneously with expansion of the expander. CONSTITUTION:This expansion catheter has a tube body 2, a first lumen 3 formed at this tube body 2, the expander 6 which is disposed at the front end of the tube body 2, is communicated with the first lumen 3 and is expandable as well as shrinkable and foldable, the liquid chemical permeable film body 7 which is disposed at the tube body 2 so as to cover the outer side of the expander 6 and a second lumen 4 which is formed at the tube body 2 and is communicated with the space formed between the film body 7 and the expander 6. The liquid chemical is fed through the second lumen 4 and fluid for expansion is fed into the expander 6 through the first lumen 3 to expand the expander 6 in the state that the front end of the tube body 2 exists in a constricted part.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dilatation catheter used for treating a stenosis formed in a body cavity such as a blood vessel.

[0002]

2. Description of the Related Art Percutaneous transluminal coronary angioplasty has been conventionally used as a means for treating a stenosis in a blood vessel by expanding the stenosis using a catheter with a dilator to improve blood flow. (Percutaneous Translum
internal CoronaryAngioplasty:
PTCA) is being conducted. Examples of such a catheter with an expandable body include a type referred to as over-the-wire in which a guide wire is freely movable inside the catheter, as shown in US Pat. No. 4,323,071, and US As shown in Japanese Patent No. 4,771,778, a type called on-the-wire in which an expansion body is directly fixed to a guide wire has been mainly used.

Further, as a means for treating a stenosis in a blood vessel with a drug, percutaneous transluminal intracoronary thrombolytic therapy (Perctaneous Transluminal)
Coronary Recanalization:
PTCR) is performed, and an imaging catheter or the like is used for administration of a drug (medicine solution).

Further, in Japanese Patent Laid-Open No. 2-283380, there is provided an expansion body which has a hole through which a chemical solution can penetrate and which expands when the chemical solution flows in, and the expansion body is expanded and brought into close contact with a stenosis. A medicinal administration catheter capable of locally administrating the medicinal solution, which allows the medicinal solution to be leached out through this expansion body, is also considered. In addition, in US Pat. No. 5,213,576, the first
Expansion body and a second expansion body coaxially arranged on the outer side of the expansion body, the expansion body having holes through which the liquid medicine can pass, and the liquid medicine can be administered through the expansion body. A body catheter is disclosed.

However, in the catheter with an expandable body described in the above publication, micropores are formed in the expandable body itself for exuding the drug solution, and the expandable body is brought into close contact with the narrowed portion while introducing the drug solution from one lumen. Moreover, since the liquid medicine is leached from the expander, the expansion of the expander and the dose of the liquid medicine must be controlled by the pressure of introducing the liquid medicine. Therefore, the pressure for expanding the expander and the simultaneous control of the amount of the liquid medicine must be controlled. It was difficult to do. In addition, when contracting the expansion body after expanding the stenosis and administering the liquid medicine, there is a possibility that blood or the like may be sucked from the micropores of the expansion body due to the decrease in the internal pressure of the expansion body. There is also a possibility that a great burden will be imposed on the above.

Further, the dilators in these catheters with dilators do not have the function of dilating the stenosis, and therefore, the angioplasty described above is performed together with the treatment with a drug so that the stenosis is more effectively performed. When it is desired to treat the stenosis, it is necessary to replace the catheter with a catheter with an expander having a dilating function, and the procedure is complicated. Also,
In such a case, the administration of the drug and the dilation of the stenosis are performed separately, and the site to which the drug is administered does not match the site to which the dilation is applied, and the treatment may not be efficiently performed. there were.

[0007]

Therefore, in view of the above-mentioned drawbacks of the prior art, the present invention can exert a physical expansion function by a catheter with an expansion body and also has a drug solution administration function independent of the expansion function. It is intended to provide a dilatation catheter.

[0008]

[Means for Solving the Problems] The above-mentioned object is as follows (1)
This is achieved by the dilatation catheter of the present invention.

(1) An expansion catheter for expanding a stenosis in a body cavity, comprising a tube body, a first lumen formed in the tube body, and a distal end portion of the tube body. An expandable body that is in communication with the lumen of the tube body, and that can be contracted or folded, a membranous liquid-permeable film body provided on the tube body so as to cover the outer side of the expandable body, and the film body formed on the tube body. An expansion catheter having a second lumen communicating with a space formed between the expansion body and the second lumen.

[0010]

The dilatation catheter of the present invention dilates a narrowed portion in a body cavity, and has a dilatable or collapsible dilator and a drug-permeable membrane provided so as to cover the outside thereof. Therefore, by simultaneously expanding the expansion body and allowing the drug to permeate through the membrane body, at the same time as the expansion of the stenosis, the drug solution is appropriately administered to the stenosis and the stenosis is effectively treated.

Further, since the expansion pressure and the drug solution introduction pressure are independent, it is easy to control the expansion pressure and the drug solution introduction pressure of the expansion body, and the drug solution can be efficiently administered to the stenosis.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below based on the embodiments shown in the drawings.

FIG. 1 is a side view of an embodiment of the dilatation catheter of the present invention, FIG. 2 is an enlarged vertical sectional view of the distal end portion of the catheter shown in FIG. 1, and FIG. 3 is a proximal end of the catheter shown in FIG. 4 is an enlarged horizontal sectional view taken along the line II of FIG. 2, and FIG. 5 is an enlarged lateral sectional view taken along the line II-II of FIG. As shown in FIG. 1, the dilatation catheter 1 has a tube body 2 and a hub 10 fixed to the proximal end of the tube body 2.

A detailed description will be given below with reference to the drawings. 2 to 5, the dilatation catheter 1 of the present invention is provided on the tube body 2, the first lumen 3 formed in the tube body 2, and the distal end portion of the tube body 2, 1. The expandable body 6 communicating with the lumen 3 of FIG. 1 and capable of expanding and contracting or folding, the drug-permeable membrane body 7 provided in the tube body 2 so as to cover the outside of the expandable body 6, and the tube body 2 Formed on the film body 7 and the expansion body 6
And a second lumen 4 communicating with the space formed between

The tube body 2 is composed of an outer tube 21, a middle tube 22 and an inner tube 23.

The outer tube 21 is a tubular body having an open front end and a rear end. As shown in FIGS. 2 and 4, the outer tube 21 is coaxially formed on the outside of the middle tube 22, and is located at the same position as the tip of the middle tube 22. Alternatively, it has a tip in a retracted position. Outer tube 21
The constituent material of is preferably formed of a material having a certain degree of flexibility, and examples of such a material include polyethylene, polypropylene, polybutene, ethylene-propylene copolymer, and ethylene-vinyl acetate copolymer. Polyolefins such as coalesced products, ionomers, or mixtures of two or more thereof, thermoplastic resins such as soft polyvinyl chloride resin, polyamide, polyamide elastomer, polyurethane and fluororesin, silicone rubber, latex rubber and the like can be used.

The outer tube 21 has a length of 300.
-2000 mm, more preferably 500-1600 mm, the outer diameter is 0.40-4.30 mm, more preferably,
0.80 ~ 1.50mm, wall thickness 30 ~ 200μm
, And more preferably 50 to 150 μm.

The middle pipe 22 is a tubular body whose front and rear ends are open. As shown in FIGS. 2 and 4, the middle pipe 22 is formed coaxially outside the inner pipe 23 and retracts from the tip of the inner pipe 23. It has a tip at the specified position.

The outer tube 2 is used as a constituent material of the middle tube 22.
As with No. 1, it is preferable to use a material having some flexibility.

The length of the middle tube 22 is 300.
˜2000 mm, more preferably 500 to 1600 mm, and the outer diameter is 0.40 to 4.30 mm, more preferably 0.
The thickness is 40 to 1.20 mm, and the wall thickness is 30 to 200 μm, more preferably 50 to 150 μm.

The inner tube 23 is a tubular body whose front and rear ends are open, and as shown in FIG.
It is arranged so as to project from the middle tube 22.

The constituent material of the inner tube 23 is the outer tube 2 described above.
1 and the same material as the middle tube 22, or various metals such as elastic metal such as stainless steel, stainless extensible alloy, Ni—Ti alloy, and various alloys such as superelastic alloy, shape memory alloy, and amorphous alloy. Can be used.

The inner tube 23 is longer than the outer tube and the middle tube and has a length of 300 to 2000 mm, preferably 500 to 1600 mm, and an outer diameter of 0.1 to 1.
0 mm, preferably 0.3-0.7 mm with a wall thickness of 10
˜150 μm, preferably 20 to 100 μm.

Then, between the middle pipe 22 and the inner pipe 23,
The first lumen 3 is formed in an annular shape, and the second lumen 4 is formed in an annular shape between the outer pipe 21 and the middle pipe 22. Furthermore, the inside of the inner tube 23 is
It is the third lumen 5 that opens at the tip of the.

The expansion body 6 can be contracted or folded around the outer circumference of the tube body 2 (in the example shown, the inner tube 23) when not expanded.
The expander 6 expands the narrowed portion of the blood vessel, and as shown in FIGS. 2 and 5, at least a part of the expander 6 has a substantially same diameter so that it can be easily expanded. Has a substantially cylindrical portion 6a. The substantially cylindrical portion may not be a perfect cylinder, and may be, for example, a polygonal column.

The tip end of the expansion body 6 is liquid-tightly fixed to the tip end of the inner pipe 23 by an adhesive or heat fusion, and the base end thereof is also liquid-tight to the tip end of the middle pipe 22. It is fixed. The inside of the expansion body 6 communicates with the first lumen 3, and the expansion fluid can flow in through the first lumen 3. Then, the expansion body 6 is expanded by the inflow of the expansion fluid, and is contracted or folded by discharging the inflowing expansion fluid.

A material having a certain degree of flexibility is preferable as a constituent material of the expansion body 6, and for example, polyolefins such as polyethylene, polypropylene, polybutene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, and ionomer. Or those cross-linked, polyester such as polyethylene terephthalate, soft polyvinyl chloride resin, polyurethane, polyphenylene sulfide, polyamide, polyamide elastomer,
A thermoplastic resin such as a fluororesin, a silicone rubber, a latex rubber, a metal, or a metal mesh can be preferably used.

Regarding the size of the expansion body 6, the outer diameter of the substantially cylindrical portion 6a when expanded is 1.0 to 30 mm, preferably 1.0 to 10.0 mm, and the length is 5 to 50 mm. It is preferably 10 to 40 mm, and the entire length of the expansion body 6 is 10
˜70 mm, preferably 15˜60 mm.

Further, the tensile strength of the expansion body 6 is 800 kg /
It is preferably cm ³ or more. This makes it possible to sufficiently satisfy the strength required to expand the narrowed portion in the blood vessel.

This tensile strength is found in Japanese Examined Patent Publication No. 63-26655.
It can be calculated by the following film equation described in the publication.

Σ ₂ = pr / h where σ ₂ is the tensile strength of the membrane (thin member forming the expansion body), p is the applied pressure, r is the radius, and h is the wall Is the thickness.

As shown in FIGS. 2, 4 and 5, the membrane body 7 is provided coaxially outside the expansion body 6 and is flexible enough to follow the expansion, contraction or folding movement of the expansion body 6. It is something. The distal end of the film body 7 is fixed by an adhesive or heat fusion at a position of the distal end of the inner tube 23, which is slightly distal to the distal end of the expansion body 6, and the proximal end is an outer tube. It is similarly fixed to the tip of 21. A space communicating with the second lumen 4 is formed between the film body 7 and the expansion body 6, and a chemical solution can be injected into the space via the second lumen 4.

The film body 7 is a substantially cylindrical portion 7 similar to the expansion body 6.
It has a and has a shape similar to that of the expansion body 6. This is preferable because it can follow the expansion / contraction or folding movement of the expansion body 6 in a good manner.

The substantially cylindrical portion 7a of the film body 7 is formed of a chemical liquid permeable material, and thus has a chemical liquid permeability. That is, after filling the space between the first lumen 3 and the expansion body 6 and the membrane body 7 with the chemical liquid, the hub 10
By further pressurizing the inside of the first lumen 3, the chemical liquid permeates the substantially cylindrical portion 7a and is gradually released to the outside of the film body 7.

Examples of the chemical liquid permeable material include semipermeable membranes, non-woven fabrics, woven fabrics, meshes and porous membranes, and the average pore diameter is about 1 to 100 μm, particularly 5 to 50 μm.
Something is preferable. The thickness and the like of the substantially cylindrical portion 7a made of these materials are set so as not to impair the flexibility even when the substantially cylindrical portion 7a is used.

Further, the tip end portion and the base end portion of the film body 7 are made of a material having a certain degree of flexibility. Examples of such materials include polyethylene, polypropylene, polybutene, ethylene-propylene copolymers, ethylene-vinyl acetate copolymers, polyolefins such as ionomers or cross-linked products thereof, polyesters such as polyethylene terephthalate, and soft polychlorinated materials. Examples thereof include thermoplastic resins such as vinyl resin, polyurethane, polyphenylene sulfide, polyamide, polyamide elastomer, and fluororesin, silicone rubber, latex rubber, metal, or metal mesh.

With this structure, since the drug solution permeates only the substantially cylindrical portion 7a of the film body 7, it is possible to reduce the amount of the drug solution released to the region other than the stenosis, and to effectively treat the affected area. In addition, when the expansion body 6 is expanded, the expansion pressure is transmitted to the drug solution and the drug solution is vigorously pushed out toward the stenosis portion, so that the drug solution can satisfactorily penetrate into the stenosis portion.

The film body 7 is not necessarily limited to the one entirely made of the above-mentioned chemical liquid permeable material, and some parts made of other materials may be provided.

Further, on the outer surfaces of the film body 7 and the outer tube 21,
In order to allow good insertion into the body cavity, for example, cellulose-based polymer substances (hydroxypropyl cellulose, etc.), polyethylene oxide-based polymer substances (polyethylene glycol), maleic anhydride-based polymer substances (eg, methyl vinyl ether anhydrous). Hydrophilic properties such as maleic anhydride copolymers such as maleic acid copolymers), acrylamide polymer materials (for example, polyacrylamide), water-soluble nylon (for example, AQ-Nylon P-70 manufactured by Toray Industries, Inc.), etc. Alternatively, it may be coated with a (water-soluble) polymer substance. As a result, when the outer surface of the tube body 2 comes into contact with blood, physiological saline, or the like, the friction coefficient is reduced and lubricity is imparted, and the slidability of the tube body 2 is further improved.

The outer surface of the expansion body 6 and the inner surface of the film body 7 may be coated with the hydrophilic (water-soluble) polymer as described above. As a result, the expansion body 6 and the membrane body 7 are well separated from each other, and the drug solution is well introduced between them.

The outermost diameter of the film body 7 is 1.0 to 3
0 mm, preferably 1.0 to 10.0 mm, the length is 5 to 50 mm, preferably 10 to 40 mm, and the entire length of the membrane body 7 is 10 to 70 mm, preferably 15 to 6
It is 0 mm.

In the illustrated example, the substantially cylindrical portion 7a is made of a chemical liquid permeable material to make the membrane 7 permeable to the chemical liquid. However, the present invention is not limited to this. It is also possible to form the membrane 7 by using the above-mentioned method and then form one or more micropores so that the drug solution can be permeated.

The diameter of such micropores is about 1 to 100 μm, preferably about 5 to 50 μm, as in the case of the chemical liquid permeable material. Further, the formation position of the micropores may be the whole of the film body 7 or only a part of the film body 7, but when the film body 7 has a substantially cylindrical portion 7a, it is provided in the substantially cylindrical portion 7a. It is preferable. As a result, the drug solution can be effectively administered from a position in close contact with the stenosis.

The formation of such minute holes can be performed, for example, by irradiating the formed film body 7 with a laser beam.

An X-ray opaque marker 8 is wound around a predetermined portion of the outer peripheral surface of the inner tube 23, which is contained in the expansion body 6, preferably at a location corresponding to the center of the substantially cylindrical portion 5a of the expansion body. There is.

The radiopaque marker 8 is made of a radiopaque material and is formed in a coil shape. The marker 8 may have a cylindrical shape, for example. The X-ray opaque material is preferably platinum, gold, tungsten or an alloy thereof, and more preferably platinum, gold or a platinum-iridium alloy. With such a material, a clear contrast image can be obtained under fluoroscopy, so that the position of the cylindrical portion 5a of the expansion body 6 can be easily confirmed under fluoroscopy.

If desired, the outer tube 21, the middle tube 22, and the inner tube 23 are each for preventing the catheter from bending at the bent portion of the blood vessel, and further for enhancing the followability of the catheter to a high degree of bending in the blood vessel. In addition, metals such as stainless steel, elastic metals, superelastic alloys, shape memory alloys, and amorphous alloys, and further synthetic fibers such as polyamide resin, polyester resin, polypropylene resin, etc.,
A rigidity imparting body may be provided in which a braided wire or a linear body made of a highly rigid material is formed in a mesh shape or a coil shape.

The hub 10 includes an outer tube hub 11 having a first opening 14 and a medium tube hub 12 having a second opening 15.
And an inner pipe hub 13 having a third opening 16, and the outer pipe hub 11, the middle pipe hub 12, and the inner pipe hub 13 are fixed in this order.

The outer tube 21 is fixed inside the outer tube hub 11. Examples of the fixing means include adhesion with an adhesive, heat fusion, and fixing with a stopper (not shown). Then, the first opening 14 communicates with the second lumen 4, and functions as a chemical injection port for introducing the chemical into the second lumen 4 and between the expansion body 6 and the membrane 7.

The middle pipe 22 is located inside the middle pipe hub 12 and is the outer pipe 2.
It is fixed like No. 1. Then, the second opening 15
Communicates with the first lumen 3 and functions as a port for introducing the expansion fluid for expanding the expansion body 6 into the first lumen 3 and discharging it from the first lumen 3.

The inner pipe 23 is provided on the inner side of the inner pipe hub 13.
It is fixed similarly to 1 and the middle tube 22. The third opening 16 communicates with the third lumen 5 and functions as a guide wire port for inserting a guide wire into the third lumen 5.

As the constituent material of the outer tube hub 11, the middle tube hub 12 and the inner tube hub 13, thermoplastic resins such as polycarbonate, polyamide, polysulfone, polyarylate, and methacrylate-butylene-styrene copolymer can be preferably used. .

Instead of providing such a branch hub, a tube having a port member for forming an opening at the rear end, for example, in each of the first lumen 3, the second lumen 4 and the third lumen 5. May be attached in a liquid-tight manner.

Further, the outer tube 21, the middle tube 22 and the inner tube 23
A reinforcing tube (not shown) for preventing the tube body 2 from being twisted or bent may be provided on the outside of each of the base ends. By installing such a tube, it is possible to prevent the tube body 2 from bending or twisting.
The lumen 3, the second lumen 4, and the third lumen 5 are prevented from being closed.

Examples of the reinforcing tube include a tubular body made of various resins such as crosslinked polyolefin and silicone rubber, a coil-shaped one made of a hard material such as metal such as stainless steel, or a combination thereof. To be Also, such a reinforcing tube 1
The length of 7 depends on its strength, but is about 1 to 100 mm,
Particularly, it is preferable to set it to about 10 to 50 mm.

In the illustrated example, the tube body 2 has a triple tube structure composed of the outer tube 21, the middle tube 22 and the inner tube 23, but the present invention is not limited to this, and for example, the first lumen 3 described above. , A single tube body provided with various lumens corresponding to the second lumen 4 and the like in parallel, and these lumens may be provided with openings communicating with the inside of the expansion body 6 and the membrane body 7. .

Next, the method of using the drug solution administration catheter of the present invention will be described by taking as an example the case of treating a stenosis occurring in a coronary artery blood vessel with the catheter shown in FIGS. 6, 7 and 8 are explanatory views showing a usage state of the catheter of the present invention.

First, before treating the narrowed part of the blood vessel, the air in the expansion body 6, the membrane body 7, the first lumen 3 and the second lumen 4 is extracted as much as possible, and the insides of the expansion body 6 and the second lumen 4 are removed. To a liquid such as a contrast medium, and to the membrane 7 and the first
The inside of the lumen 3 is replaced with a drug solution for treating the stenosis. At this time, the expansion body 6 and the membrane body 7 are in a contracted or folded state as shown in FIG.

Next, a sheath is placed in the patient's blood vessel by, for example, the Seldinger method, and the distal end portion of the tube body 2 in a state where the guide wire 15 is inserted into the third lumen 5 so as to protrude by about 5 to 50 mm. Is inserted into the blood vessel through the lumen of the sheath. Subsequently, the guide wire 1 is checked while visually recognizing the positions of the markers 8 and the positions of the distal ends of the tube body 2 and the guide wire 15 under fluoroscopy.
5, the catheter 1 is advanced, and the catheter 1 reaches the narrowed portion 32 as shown in FIG.

Next, the tip of the tube body 2 is constricted in the narrowed portion 3.
2, the first opening portion 14 of the outer tube hub 11 is located
A predetermined amount of the chemical liquid is injected at a pressure equal to or higher than a predetermined value, the chemical liquid is sent through the second lumen 4, and the middle pipe hub 12
A predetermined amount of an expansion fluid such as a contrast agent is injected from the second opening 15 of the syringe using a syringe or the like, and the expansion fluid is sent into the inside of the expansion body 6 through the first lumen 3 to Inflate. As a result, as shown in FIG.
The drug solution leaches to the outside through the membrane body 7, fills the vicinity of the stenosis portion 32, and further, the expansion pressure of the expansion body 6 is applied to penetrate the stenosis portion well.

When the expansion body 6 expands, the expansion body 6 reaches the narrowed portion 32 and expands the narrowed portion 32 as shown in FIG. At this time, the drug solution filled in the vicinity of the stenosis 32 is pressed against the stenosis 32 by the expansion of the expansion body 6, whereby the drug solution penetrates into the stenosis 32 better.

During this time, since the control of the expansion pressure of the expansion body 6 and the control of the injection amount of the chemical liquid are performed independently, the expansion pressure and the dose of the chemical liquid to the stenotic portion can be adjusted as desired depending on the degree of stenosis. Can be done easily.

The administration of the liquid medicine and the expansion of the expansion body 6 may be performed by first expanding the expansion body 6 and then injecting the liquid medicine through the first opening 14, or vice versa. Good.

After expanding the stenosis, a second expansion fluid is used.
Then, the expansion body 6 is sucked and discharged through the opening 15 and the expansion body 6 is brought into a contracted or folded state. Then, the tube body 2 is removed from the blood vessel through the sheath, and the procedure is completed.

The drug solution may be administered when the expansion fluid is discharged. Further, the injection of the chemical liquid from the opening portion 14 may be stopped at the same time when the expansion fluid is discharged.

Although the dilatation catheter of the present invention has been described above by taking a catheter for treating a stenosis of a blood vessel as an example, the present invention is not limited to application in the blood vessel, and for example, for the ureter, for the bile duct, for the fallopian tube, It can be applied to various uses such as for liver ducts.

Further, in the illustrated example, the over-the-wire type dilatation catheter in which the lumen for inserting the guide wire is defined is used, but the present invention is not limited to this, and the dilation body is directly fixed to the guide wire. On-the-wire type dilatation catheter and US Pat.
It can also be applied to the monorail-type dilatation catheter in which the guide wire can be exchanged while the catheter is still inserted in the blood vessel, etc. described in the specification of 48,982.

[0068]

As described above in detail, the dilatation catheter of the present invention is provided with a tube body, a first lumen formed in the tube body, and a distal end portion of the tube body. Communicating with the lumen of, expandable and contractible or foldable expansion body, the drug solution permeable membrane provided in the tube body so as to cover the outside of the expansion body, formed in the tube body, A second lumen communicating with a space formed between the film body and the expansion body, and a chemical solution causes the second lumen and the film body to be in a state where the expansion body is inflated. It is characterized in that it is administered to the outside of the membrane through the expansion body, so that the membrane can be brought into close contact with the inside of the body cavity such as a blood vessel by inflating the expansion body, and the medicinal solution can be accurately administered to the affected area within the body cavity.

Further, since the expansion pressure and the drug solution introduction pressure are independent of each other, the expansion pressure and the drug solution introduction pressure of the expander are separately controlled, which facilitates these controls, and the expansion of the expander and the vicinity of the blood vessel wall. The drug solution can be efficiently administered.

[Brief description of drawings]

FIG. 1 is a side view of an embodiment of the dilatation catheter of the present invention.

FIG. 2 is an enlarged vertical sectional view of a distal end portion of the dilatation catheter shown in FIG.

FIG. 3 is an enlarged vertical sectional view of a proximal end portion of the dilatation catheter shown in FIG.

FIG. 4 is an enlarged cross-sectional view taken along the line II of FIG.

5 is an enlarged cross-sectional view taken along the line II-II of FIG.

FIG. 6 is an explanatory view showing a usage state of the dilatation catheter of the present invention.

FIG. 7 is an explanatory view showing a usage state of the dilatation catheter of the present invention.

FIG. 8 is an explanatory view showing a usage state of the dilatation catheter of the present invention.

[Explanation of symbols]

 1 dilatation catheter 2 tube main body 3 first lumen 4 second lumen 6 dilatation body 7 membrane body

Claims (1)

[Claims] 1. A dilatation catheter for dilating a stenosed part in a body cavity, comprising a tube body, a first lumen formed in the tube body, and a first lumen provided at a distal end portion of the tube body. An expansion body that communicates with the lumen and is capable of contracting or folding, a drug solution permeable film body provided on the tube body so as to cover the outside of the expansion body, and formed on the tube body. An expansion catheter having a second lumen communicating with a space formed between the expansion body and the second lumen.