JP2001070451A - Balloon catheter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable the observation under fluoroscopy without using a marker consisting of a metallic pipe. SOLUTION: This balloon catheter 1 has a shaft 3, a balloon 5, a connector 7, etc. The greater part of the shaft 3 consists of material which is transparent to X-rays and only the portion (hatched part in Figure) of the tube 3b which penetrates the inside of the balloon 5 is formed as an X-ray hardly transmittable part 9 formed of a resin material through which the X-rays are hardly transmittable. A resin material which basically consists of polyethylene and is formed by kneading tungsten powder therein is utilized as the resin material through which the X-rays are hardly transmittable.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a balloon catheter.

[0002]

2. Description of the Related Art A balloon catheter has conventionally been used, for example, when performing PTCA (percutaneous coronary angioplasty). This type of balloon catheter has a structure in which a balloon is provided on the outer periphery of the distal end side of a flexible and elongated shaft. In the case of PTCA, the balloon catheter is inserted into the blood vessel of the patient and the balloon is moved to the treatment site. By expanding the balloon inside the stenosis serving as a treatment site, a dilation treatment for the stenosis can be performed.

[0003]

Incidentally, whether or not the balloon has reached the treatment site is confirmed by an X-ray fluoroscope, but it is difficult to observe the balloon itself under X-ray fluoroscopy. Has mounted a marker made of a metal tube such as gold or platinum on the outer periphery of a shaft penetrating the inside of the balloon, and determined the position of the balloon based on the shadow of the metal marker.

[0004] However, when a metal marker is attached to the outer periphery of the shaft, the diameter of the shaft is increased by the amount of the metal marker, which has been a factor that hinders the reduction in the diameter of the balloon catheter. If the tip of the balloon catheter becomes excessively hard, the blood vessel wall may be damaged when the balloon catheter is inserted. Therefore, the above-described metal marker cannot be attached to the tip of the balloon catheter. For this reason, it is not easy to confirm the tip position of the balloon catheter even under fluoroscopy, and it is necessary to predict whether the tip of the balloon catheter is at an appropriate position based on the experience and skill of the operator. There was a problem that only can be done.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a balloon catheter which can be observed under fluoroscopy without using a marker made of a metal tube.

[0006]

Means for Solving the Problems and Effects of the Invention Hereinafter, features of the present invention made to achieve the above object will be described in detail. The balloon catheter of the present invention has a shaft having a fluid supply / drainage passage formed therein, which has an elongated shape that flexibly bends and extends from a proximal end side to a distal end side, and is provided at a distal end side of the shaft. A balloon that expands when a fluid is supplied to the inside through the fluid supply / discharge channel, and that contracts when the fluid inside is discharged, wherein at least a part of the shaft is X.
It is characterized in that it is an X-ray hardly permeable portion formed of a resin material containing a hardly radiolucent substance.

In this balloon catheter, the X-ray impervious substance is a substance that is hardly penetrable by X-rays and may be any substance that can be easily kneaded into a resin material serving as a base. For example, it is preferable to use a tungsten compound, a bismuth compound, a barium compound, or the like.

As the tungsten compound, powdered tungsten can be typically used, but other tungsten compounds may be used as long as they have a contrast effect. As the bismuth compound, typically, bismuth oxide or the like can be used, but this may also be another bismuth compound. As the barium compound, barium sulfate or the like can be typically used, but another barium compound may also be used.

Any of these may be used alone, or a mixture of two or more of them may be used, but a tungsten compound is particularly preferred in terms of excellent contrast. As a resin material serving as a base when kneading these X-ray impermeability substances, for example, silicon, vinyl chloride,
Resin materials that can be used for medical devices, such as polyethylene, polyamide, polyurethane, and various other elastomers, can be arbitrarily used.

The mixing ratio of the X-ray impervious substance, the base resin material, and other additives is appropriately adjusted in consideration of the strength, flexibility, contrast, and the like required for the shaft. Well, usually, about 30 to 70% by weight of X
What is necessary is just to contain a radiopaque material.

[0011] The balloon is not particularly limited as long as it is a resin material which can be expanded and contracted flexibly and has no problem for medical devices, as in the case of a conventional balloon catheter. Examples of the material include polyurethane, latex, and silicone. Rubber, natural rubber, polyvinyl chloride, polyamide, polyamide elastomer and the like can be used.

By the way, as the fluid used to expand the balloon, gas or liquid can be used,
Liquid is desirable in that the volume change due to pressure is small, and physiological saline or an aqueous solution of a contrast agent can be used. As the gas, an inert gas such as helium gas is preferable.

[0013] The range of the X-ray opaque portion may vary depending on the main purpose, but in order to confirm the position of the balloon, the range overlapping the position where the balloon is provided is defined as the X-ray opaque portion. Good to be. Further, in order to confirm the position of the distal end of the balloon catheter, the range including the distal end of the shaft may be set as the X-ray hardly permeable portion.

According to the balloon catheter constructed as described above, the X-ray hardly permeable portion is formed of a resin material containing a hardly X-ray permeable substance. Observation under X-ray fluoroscopy can be performed without the need. Therefore, if the X-ray hardly permeable portion is provided in accordance with the position of the balloon, the metal marker becomes unnecessary, and the diameter of the balloon catheter can be reduced by that much.

Further, since the resin material containing the radiopaque material is not as hard as metal, the radiopaque portion may be in a range including the distal end of the shaft. The tip position of the balloon catheter can be easily confirmed without relying on the experience and skill of the person.

Further, if the X-ray hardly permeable portions are provided at intervals so as to form a stripe pattern on the shaft,
When viewed under fluoroscopy, the guidewire looks different from a mere linear guidewire, so that it can be easily distinguished from a guidewire. The stripe pattern is a vertical stripe substantially parallel to the longitudinal direction of the shaft, a horizontal stripe substantially perpendicular to the longitudinal direction of the shaft,
Alternatively, any form of stripe pattern such as a stripe extending spirally along the shaft may be used.

[0017]

Next, an embodiment of the present invention will be described with reference to an example. As shown in FIG. 1, the balloon catheter 1 includes a shaft 3, a balloon 5, a connector 7, and the like.

The shaft 3 is a double tube formed by inserting the inner tube 3b into the inner cavity of the outer tube 3a, and a part of the inner tube 3b projects from the distal end of the outer tube 3a to form the balloon 5 Penetrates the inside of the. Although not explicitly shown in the figure, the outer tube 3a and the inner tube 3
b are joined to each other at several places so that they are not relatively displaced.

The inner surface of the outer tube 3a and the outer surface of the inner tube 3b form a gap communicating with the inside of the balloon 5, and this gap forms a fluid supply / discharge path 3c to the balloon 5. The inner lumen of the inner tube 3b has a guide wire insertion passage 3 for passing a guide wire inserted into the blood vessel prior to inserting the balloon catheter 1 into the blood vessel.
d.

Most of the shaft 3 is made of polyethylene.
Although it is made of a material that transmits X-rays, the inner tube 3b
Only the portion penetrating the inside of the balloon 5 (the hatched portion in FIG. 1) is an X-ray resistant portion 9 made of a resin material that is difficult to transmit X-rays. In the present embodiment, as the resin material that is difficult to transmit X-rays, a resin in which tungsten powder is kneaded based on polyethylene is used.

The balloon 5 is made of polyethylene and has a proximal end joined near the distal end of the outer tube 3a and a distal end joined near the distal end of the inner tube 3b.
The connector 7 is made of polycarbonate, and has a fluid supply port 7a protruding in a cylindrical shape and a guide wire insertion port 7b.

According to the balloon catheter 1 configured as described above, since the X-ray hardly permeable portion 9 is formed of a resin material containing an X-ray hardly permeable substance, the conventional metal marker is used. Observation under X-ray fluoroscopy can be performed without wearing the camera. Therefore, when checking the position of the balloon 5, a metal marker as in the conventional product is not required, and the diameter of the balloon catheter 1 can be reduced by that much.

Further, since the distal end of the shaft 3 is constituted by the X-ray impervious portion 9, it is possible to easily confirm the tip position of the balloon catheter 1 without depending on the experience and skill of the operator. it can. By the way, the portion of the inner tube 3b penetrating through the inside of the balloon 5 (the hatched portion in FIG. 1) is the X-ray hardly permeable portion 9, so that it is linear under X-ray fluoroscopy. Looks like. On the other hand, the guide wire passed through the inside of the inner tube 3b also looks linear under X-ray fluoroscopy. Under such circumstances, in order to make it easy to distinguish between the X-ray hardly permeable portion 9 and the guide wire,
The entirety of the specific range of the tube may not be an X-ray transmission part, and the X-ray transmission part 9 may be provided intermittently.

More specifically, for example, as shown in FIGS. 2A and 2B, linear X-rays are spaced at intervals so as to form vertical stripes on the inner tube 11. It is preferable to provide the hardly permeable portion 13. In this way, when the inner tube 11 is viewed under X-ray fluoroscopy, the X-ray hardly permeable portion 13
However, since it looks different from a linear guide wire, it can be easily distinguished from a guide wire.

Alternatively, for example, as shown in FIG.
It is preferable to provide cylindrical X-ray hardly permeable portions 17 at intervals.
Even in this case, when the inner tube 15 is viewed under X-ray fluoroscopy, the X-ray hardly permeable portion 17 looks different from a linear guide wire, so that it is easy to distinguish the guide tube from the guide wire. Becomes

Although the embodiment of the present invention has been described above, various specific embodiments other than those described above can be considered for the embodiment of the present invention. For example, the balloon catheter 1 is a so-called double lumen type in which the shaft 3 is constituted by the outer tube 3a and the inner tube 3b, but employs a shaft having two lumens formed in parallel. In this case, the same effect as that of the balloon catheter 1 can be obtained by providing a part of the shaft as the X-ray opaque portion.

Also, a so-called single lumen type balloon catheter may be constituted by employing a shaft having one lumen, and even in this case, a part of the shaft is provided as an X-ray hardly permeable portion. The same effect as that of the balloon catheter 1 can be obtained.

[Brief description of the drawings]

FIG. 1 is a balloon catheter exemplified as an embodiment of the present invention, (a) is a side view showing the entirety thereof,
(B) is an enlarged view near the balloon.

FIGS. 2A and 2B show a tube provided with an X-ray resistant part so as to form a vertical stripe pattern, FIG. 2A being a perspective view thereof, and FIG.
Is a sectional view thereof.

FIG. 3 is a perspective view showing a tube provided with an X-ray resistant part so as to form a horizontal stripe pattern.

[Explanation of symbols]

1 ... balloon catheter, 3 ... shaft, 3a
... outer tube, 3b, 11, 15 ... inner tube, 3c ... fluid supply / discharge path, 3d ... guide wire insertion path, 5 ... balloon, 7 ... connector, 7a
..Fluid supply port, 7b ... guide wire insertion port, 9,
13, 17 ... X-ray hardly permeable part.

Claims (4)

[Claims] A shaft having a fluid supply / drainage passage formed therein extending from a proximal end side to a distal end side and having a flexible curved elongated shape, provided at a distal end side of the shaft; A balloon catheter comprising: a balloon that expands when a fluid is supplied to the inside through the fluid supply / discharge passage, and expands when the inside fluid is discharged, wherein at least a part of the shaft is a radiopaque material. A balloon catheter characterized in that it is an X-ray hardly permeable portion formed of a resin material containing: 2. The balloon catheter according to claim 1, wherein the X-ray hardly permeable portion has a range including a distal end of the shaft. 3. The balloon catheter according to claim 1, wherein the X-ray hardly permeable portions are provided at intervals so as to form a stripe pattern on the shaft. 4. The method according to claim 1, wherein the X-ray hardly permeable material is one or a mixture of two or more selected from a tungsten compound, a bismuth compound, and a barium compound. 4. The balloon catheter according to any one of 3.