JPH0956825A - Hot balloon catheter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hot balloon catheter with which the formation to a smaller diameter is possible and production is easy. SOLUTION: This blood expanding catheter has an outer tube 2 and an inner tube 1, and has a balloon 3 at its front end. The inner tube 1 nearer the front end side than the balloon 3 including the part enclosed by the balloon 3 is provided with an electrode 4 for high frequency energization 4 (hereafter merely described as a electrode) and is provided with a counter electrode layer on the base end in proximity to the electrode 4 of the inner tube 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hot balloon catheter used for so-called vasodilation, which expands a stenosis of a blood vessel, particularly a heart blood vessel due to arteriosclerosis.

[0002]

2. Description of the Related Art Conventionally, as a hot balloon catheter used for vasodilation, a catheter having a balloon capable of inflating and deflating at its distal end has a high-frequency energizing electrode integrally incorporated in an inner tube. Things have been proposed. When treating a stenosis of a blood vessel, high-frequency dielectric heating heats the stenosis at an appropriate temperature to improve elastic fiber extension of the tunica media, and also plasticizes thrombus and other lipids. While doing so, the balloon is pressurized and inflated to mechanically crush blood vessels and atheroma, and to extend the blood vessel wall to expand the stenosis and improve blood flow (JP-A-3-251258, JP Kaihei 4-24
6367, JP-A-6-98937, etc.).

The balloon catheter disclosed in Japanese Unexamined Patent Publication (Kokai) No. 3-251258 has a high-frequency energizing electrode provided on the outer circumference of a hollow catheter shaft. A high-frequency voltage is applied between this electrode and an electrode plate arranged outside the living body to form a balloon. This is a method for locally dielectrically heating a narrowed portion of a blood vessel wall having a large dielectric loss rate in contact with the film. In addition, JP-A-4-24636
The balloon catheter of Japanese Patent No. 7 is provided with a high-frequency energizing electrode on the catheter shaft in the balloon and a plurality of small holes for perfusing a cooling liquid in the catheter shaft in the balloon. The intimal surface of the blood vessel that contacts the balloon is not cauterized. The hot balloon catheter disclosed in Japanese Patent Laid-Open No. 6-98937 has a shaft having a high frequency energizing function and a guide wire having an electrode portion at the distal end thereof. The tip of the hot wire catheter is inserted through the guide wire having the high frequency energizing function. A high-frequency voltage is applied between the electrode part of the abdomen and the counter electrode plate applied to the back of the patient, etc., whereby the vicinity of the stenotic site of the blood vessel is dielectrically heated.

However, these conventional hot balloon catheters have the drawback that it takes time to prepare for the procedure because the counter electrode is separately provided outside the body. In addition, since high-frequency current is applied across the living body and the distance between the electrodes is long, power consumption is large, and it is difficult to control the heating temperature. Therefore, it is difficult to locally heat the target site only. Had.

[0005]

In general, a hot balloon catheter is one in which a high frequency current is passed between two electrodes to heat a vascular stenosis, and a balloon having a single pole and a bipolar are provided. Although it may be provided, the bipolar type, in spite of the above circumstances, has a problem that it is difficult to reduce the diameter of the catheter because the two electrodes are provided inside the balloon, and it is also difficult to manufacture. The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a hot balloon catheter that can be reduced in diameter and is easy to manufacture.

[0006]

In order to solve the above problems, the present invention has an outer tube and an inner tube, and a portion surrounded by a balloon in a vasodilation catheter having a balloon at the distal end thereof. A hot balloon catheter characterized in that a high-frequency current-carrying electrode is provided on the inner tube on the distal side of the balloon containing the, and a counter electrode layer is provided on the proximal side in the vicinity of the high-frequency current-carrying electrode of the inner tube. ing. Here, the high-frequency current-carrying electrode may be provided in a portion surrounded by the balloon or may be provided adjacent to the balloon and closer to the distal end side than the balloon. Further, as the combination of the electrode and the counter electrode layer, a metal core wire as an electrode is inserted and fixed in the inner cavity of the inner tube, and the outer wall of the inner tube is plated with metal as a counter electrode layer. , A structure in which a resin layer in which a metal core wire as an electrode is embedded is formed on the tube wall of the inner tube, and the outer wall of the inner tube is plated with metal as a counter electrode layer, the tube wall of the inner tube is A resin layer in which a metal core wire as an electrode is embedded is formed, and a metal as a counter electrode layer is plated on the outer wall of the resin layer.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described with reference to the drawings. 1 is an explanatory view showing an embodiment of the present invention, and FIG. 2 is a sectional view taken along the line AA of FIG. FIGS. 3, 5, 7, and 9 are explanatory views showing other embodiments of the present invention, and FIGS. 4, 6, 8 and 10 are FIGS. 3, 5, and 7, respectively. 10 is a sectional view taken along the line AA of FIG. 9. As shown in FIGS. 1 to 10, the hot balloon catheter of the present invention has an outer tube 2 and an inner tube 1 and is surrounded by a balloon 3 in a vasodilation catheter having a balloon 3 at a distal end thereof. A high-frequency current-carrying electrode 4 (hereinafter simply referred to as an electrode) is provided on the inner tube 1 on the distal side of the balloon 3 including the portion, and a counter electrode layer 5 is provided on the proximal end side close to the electrode 4 of the inner tube 1. It has a feature.

The hot balloon catheter shown in FIG.
A metal core wire as the electrode 4 is inserted and fixed in the inner cavity of the inner tube 1, and the electrode 4 is attached to the outer wall of the inner tube 1.
The balloon 3 is adhered and fixed to the distal end portion of the outer tube 2 and the distal end portion of the inner tube 1 in such a manner that the counter electrode layer 5 is plated with metal in close proximity to the. The inner tube 1 and the outer tube 2 are flexible resins such as olefin resins such as ethylene-vinyl acetate copolymer, polyethylene, polypropylene and ethylene-propylene copolymer, and polytetrafluoroethylene and tetrafluoroethylene-. Fluorine-based resin such as propylene hexafluoride copolymer,
It is a tube made of polyester, polyvinyl chloride, polyurethane, polyethylene terephthalate (PET), polyamide, etc., so that the inner tube 1 secures a passage (lumen 8) for injecting a balloon inflation liquid in the inner lumen of the outer tube 2. Is attached to.

The outer wall of the inner tube 1 is metal-plated as a counter electrode layer 5 in the vicinity of (may be adjacent to) the electrode 4. As a material for forming the electrode 4, copper, iron,
Metals such as nichrome, silver, gold and platinum can be adopted, and gold and platinum which are particularly biocompatible are preferable. Electrode (core wire)
When the forming material of 4 is expensive gold or platinum, the electrode 4 is formed as thin as possible, and the resin layer 6 for closing the entire inner cavity as shown in FIG. Provided,
It is preferable to fix the electrode 4 to the inner tube 1 by embedding it in this. Further, the counter electrode layer 5 is preferably provided on the proximal end side in the vicinity of the electrode 4 of the inner tube 1, and as the metal used for plating, gold, platinum, copper, silver or the like can be adopted, and particularly the living body. Gold and platinum, which have good compatibility, are preferable.
Although not shown, the electrode 4 and the counter electrode layer 5 are preferably connected to a high frequency power source by a lead wire or the like.

The balloon 3 is a thin film having a wall thickness of generally 0.001 to 0.1 mm, which is adhered to the distal ends of the inner tube 1 and the outer tube 2 by a method such as an adhesive or heat welding, and has appropriate toughness. A material having strength, for example, ethylene-butylene-styrene / block copolymer mixed with low-molecular weight polystyrene and optionally polypropylene, polyvinyl chloride, polyester, thermoplastic rubber,
Silicone-polycarbonate copolymer, ethylene-vinyl acetate copolymer, polyethylene terephthalate, polyamide and the like are preferably adopted.

The hot balloon catheter shown in FIGS. 3 and 4 has a guide wire passage 71 on the inner wall of the inner tube 11.
The resin layer 61 is provided so that the inner tube 1 is embedded in the resin layer 61.
Proximity to the electrode 41 on the outer wall of 1 (may be adjacent)
The counter electrode layer 51 is metal-plated.
In the case of the configuration in which the electrode is provided on the inner wall of the inner tube,
As shown in FIG. 6, the counter electrode layer 52 may be provided on the outer wall of the resin layer 62. The hot balloon catheter shown in FIGS.
A resin layer 63 is provided on the outer wall of the inner tube 13, an electrode 43 is embedded in the resin layer 63, and a counter electrode layer 53 is provided on the outer wall of the inner tube 13 close to (may be adjacent to) the electrode 43. It has been metal-plated. In the case of a configuration in which the electrodes are provided on the outer wall of the inner tube,
As shown in FIGS. 9 to 10, the counter electrode layer 54 may be provided on the outer wall of the resin layer 64.

Next, the use of the hot balloon catheter of the present invention will be described with reference to FIG. The hot balloon catheter of the present invention is percutaneously inserted into a blood vessel, and the distal end portion of the inner tube 1 is positioned beyond the narrowed site of the blood vessel. At this time, the balloon 3 is located exactly at the stenosis site of the blood vessel. When saline or the like as a balloon inflation fluid is injected into the balloon 3 via the lumen 8,
The balloon 3 expands and presses the narrowed portion. Then, when a high frequency voltage is applied between the electrode 4 and the counter electrode layer 5, the vicinity of the narrowed portion of the blood vessel is dielectrically heated. In this way, the narrowed portion of the blood vessel is expanded by heating and compression.

[0013]

As is apparent from the above description, by adopting the hot balloon catheter of the present invention, a catheter having a small diameter can be used, so that the operation of inserting the catheter into a blood vessel and guiding it to the affected area is smooth. Can be done. Moreover, since the manufacturing is easy, the catheter can be provided at a low cost.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing an embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is an explanatory view showing another embodiment of the present invention.

FIG. 4 is a sectional view taken along line AA of FIG. 3;

FIG. 5 is an explanatory view showing another embodiment of the present invention.

FIG. 6 is a sectional view taken along line AA of FIG. 5;

FIG. 7 is an explanatory view showing another embodiment of the present invention.

8 is a cross-sectional view taken along the line AA of FIG.

FIG. 9 is an explanatory diagram showing another embodiment of the present invention.

10 is a cross-sectional view taken along the line AA of FIG. 9.

[Explanation of Codes] 1, 11, 12, 13, 14 Inner Tube 2, 21, 22, 23, 24 Outer Tube 3, 31, 32, 33, 34 Balloon 4, 41, 42, 43, 44 Electrode (core wire) 5, 51, 52, 53, 54 Counter electrode layer 6, 61, 62, 63, 64 Resin layer 71, 72, 73, 74 Guide wire passage

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[Procedure amendment]

[Submission date] September 25, 1996

[Procedure amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] 0002

[Correction method] Change

[Correction contents]

[0002]

2. Description of the Related Art Conventionally, as a hot balloon catheter used for vasodilation, a catheter having a balloon capable of inflating and deflating at its distal end has a high-frequency energizing electrode integrally incorporated in an inner tube. Things have been proposed. When treating a stenosis of a blood vessel, high-frequency dielectric heating heats the stenosis at an appropriate temperature to improve elastic fiber extension of the tunica media, and also plasticizes thrombus and other lipids. While doing so, the balloon is pressurized and inflated to mechanically crush the thrombus or atheroma, the blood vessel wall is extended to expand the stenosis, and the blood flow is improved (Japanese Patent Laid-Open No. 3-251258, Kaihei 4-24
6367, JP-A-6-98937, etc.).

Claims (6)

[Claims] 1. A vasodilation catheter having an outer tube and an inner tube and having a balloon at its tip, wherein a high-frequency conducting electrode is provided on the inner tube on the tip side of the balloon including a portion surrounded by the balloon. At the same time, a hot balloon catheter characterized in that a counter electrode layer is provided on the proximal end side of the inner tube in the vicinity of the high-frequency current-carrying electrode. 2. The hot balloon catheter according to claim 1, wherein a high-frequency current-carrying electrode is provided in a portion surrounded by a balloon. 3. The hot balloon catheter according to claim 1, further comprising a high-frequency current-carrying electrode provided adjacent to the balloon and on the distal side of the balloon. 4. A metal core wire as an electrode is inserted and fixed in an inner cavity of the inner tube, and a metal as a counter electrode layer is plated on an outer wall of the inner tube.
The hot balloon catheter according to any one of to 3. 5. A resin layer in which a metal core wire as an electrode is embedded is formed on the tube wall of the inner tube, and a metal as a counter electrode layer is plated on the outer wall of the inner tube. The hot balloon catheter according to any one of 3 above. 6. A resin layer having a metal core wire as an electrode embedded therein is formed on the tube wall of the inner tube, and the outer wall of the resin layer is plated with a metal as a counter electrode layer. The hot balloon catheter according to any one of to 3.