JPH0720495B2 - catheter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial field of use> The present invention relates to a catheter having an extremely small diameter, for example, a catheter for PTCA, which is used by being inserted into a peripheral blood vessel.

<Prior Art> Conventionally, when inserting a catheter into a body cavity such as a blood vessel or urethra, a guide wire inserted into the lumen of the catheter is advanced to reach the target site.

As an example of a PTCA catheter for expanding the stricture in the blood vessel, with the guide wire inserted in the lumen of the catheter, select the bifurcation of the blood vessel by operating the guide wire at the proximal end of the catheter. And then inserted into the peripheral blood vessel (for example, coronary artery) having a stenosis.

The method of holding the catheter and the guide wire at the proximal end of the catheter at this time varies depending on the operator. For example, as shown in FIG. 5, the tip of the guide wire 6 can be seen through X-rays and the thumb of the left hand can be seen. Pinch the guide wire 6 with your forefinger and push it in, and use the other finger of your left hand to insert the catheter.
While holding the hub 13 attached to the base end of the guide wire 6, while holding the base end of the guide wire 6 with the right hand,
A technique is performed in which a torque is applied to the blood vessel and the tip of the guide wire is rotated to direct it toward a target direction at the bifurcation of the blood vessel.

In this procedure, the force for moving the guide wire 6 and the force for applying the torque require a delicate sensation, and therefore, it is necessary to firmly hold the catheter 11.

However, because the part to be held differs depending on the operator, the base end of the catheter could not be formed into a shape suitable for holding, and the functional aspect of the catheter was emphasized exclusively, and the design was not made considering operability. .

That is, since the hub 13 at the proximal end of the catheter and the subsequent catheter 11 have small diameters, it is difficult to hold them reliably.

Therefore, the operator cannot concentrate on the operation of the guide wire 6, which may hinder accurate operation.

<Problem to be Solved by the Invention> An object of the present invention is to provide a catheter which can easily and accurately operate a guide wire by securely holding a proximal end portion of the catheter.

<Means for Solving the Problems> Such an object is achieved by the present invention described below.

That is, the present invention relates to a catheter which is used by being inserted into a peripheral blood vessel and which has a catheter body having a lumen through which at least one guide wire is inserted, and a hub which supports a proximal end portion of the catheter body. The hub is integrally formed with the hub or is formed of a separate member, and has a gripping shape portion that is positively provided for facilitating gripping. The catheter is equipped with a reinforcing tube body capable of preventing the lumen from being closed due to bending or twisting.

Further, the grasping shape portion is preferably a catheter having a polygonal cross section.

Further, it is preferable that the grasping shape portion is a catheter having a concave portion or a convex portion for preventing slippage.

The gripping shape portion is formed so as to project from the hub toward the distal end side of the catheter body, and the reinforcing tube body projects from the gripping shape portion toward the distal end side of the catheter body for a predetermined length. It is preferably a catheter that is fitted.

<Examples> Hereinafter, preferred examples of the catheter of the present invention shown in the accompanying drawings will be described in detail.

A PTCA catheter for expanding the intravascular stenosis will be described representatively, but the catheter of the present invention is not limited to this.

FIG. 1 and FIG. 2 are vertical cross-sectional views showing a configuration example of a proximal end portion and a distal end portion of a catheter of the present invention, and FIG. 3 is a sectional view taken along line AA in FIG. .

The catheter 1 of the present invention is composed of a catheter body 2, a hub 3 that supports the proximal end portion thereof, and a gripping shape portion 4 provided at the distal end portion of the hub 3.

The catheter body 2 is configured as a long tubular body having a double tubular structure in which an inner tube 21 and an outer tube 22 are provided substantially coaxially.

A first lumen 23 is formed in the inner pipe 21, and a second lumen 24 is formed between the inner pipe 21 and the outer pipe 22.

The first lumen 23 is a lumen for mainly inserting the guide wire 6, injecting a drug solution into a blood vessel, measuring blood pressure, and the like, and is open to the tip of the catheter body 2.

The second lumen 24 is a lumen serving as a fluid flow path for expanding the expansion body 25, which will be described later, and communicates with the internal space 26 of the expansion body 25.

The constituent material of the inner tube 21 and the outer tube 22, polyethylene, polypropylene, ethylene-vinyl acetate copolymer,
Examples thereof include thermoplastic resins such as polyurethane, polyester and polyamide elastomer, silicone rubber, latex rubber and the like. It is also possible to mix an X-ray opaque material (barium sulfate, bismuth oxide, tungsten, etc.) into these materials so that the position of the catheter body can be confirmed under X-ray fluoroscopy.

In order to enhance the torque transmissibility of the catheter body 2,
Alternatively, a stiffening body (not shown) may be installed in the inner tube 21 and / or the outer tube 22 in order to prevent the catheter body 2 from being bent or twisted. Specific examples of the rigidity imparting body include those in which a mesh made of, for example, a fine metal wire is embedded in a portion of the inner tube 21 and / or the outer tube 22, preferably excluding the tip.

As shown in FIG. 2, at the distal end of the catheter body 2, the distal end of the outer tube 22 is installed at a position retracted from the distal end of the inner tube 21 toward the proximal side by a predetermined distance, and A tubular expansion body (balloon) 25 is installed between the distal end portion of the tube 22 and the tube 22. The expansion body 25 is made of a thin film made of cross-linked polyolefin, polyester, silicone rubber, latex rubber, or the like, and expands or contracts (or is folded) as the expansion fluid (for example, contrast agent) is injected or removed. It is possible.

The thickness of the expansion body 25 is preferably about 3 to 60 μm.

The length of the expanded portion of the expansion body 25 is preferably about 10 to 50 mm, and the diameter (average) when expanded is preferably about 1 to 10 mm.

Such an expansion body 25 is attached at its both ends to the outer peripheral surface of the inner tube 21 and the outer peripheral surface of the outer tube 22 by an adhesive agent or by a method such as binding with a thread or the like (not shown). .

A marker 27 made of a radiopaque material is provided at, for example, two positions (in the example shown, the distal end and the proximal end of the expanded portion of the expanded body 25) on the outer peripheral surface of the inner tube 21 covered with the expanded body 25. is set up.

Thereby, the position of the expansion body 25 can be confirmed under fluoroscopy.

Specific examples of the marker 27 include gold, platinum, tungsten,
Alternatively, a ring formed of a metal such as an alloy containing these may be fixed to the outer peripheral surface of the inner tube 21 by caulking, for example.

In order to obtain lubricity (prevention of adhesion) with the inner wall of the blood vessel to be inserted, such an outer surface of the catheter body 2 is made of, for example, poly (2-hydroxyethyl methacrylate), polyhydroxyethyl acrylate, hydroxypropyl cellulose, methyl. It is preferable to coat a hydrophilic polymer such as vinyl ether, maleic anhydride copolymer, polyethylene glycol, polyacrylamide or polyvinylpyrrolidone.

As the guide wire 6 inserted into the first lumen 23, for example, an X-ray impermeable material (barium sulfate, bismuth oxide, tungsten, etc.) is provided on the outer circumference of a core wire made of a superelastic alloy (Ni-Ti alloy, etc.). The thing which coat | covered the coating material which consists of the compounded polyurethane is mentioned.

The guide wire 6 has a diameter of about 0.3 to 1.6 mm.

The catheter body 2 is not limited to the double-tube structure described above, and may have any structure such as one lumen formed or two or more lumens arranged in parallel.

The hub 3 is a C-shaped hollow member that is bifurcated, and has a guide wire port 31 on one side of the branch pipe and an injection port 32 on the other side.

At the proximal end of the catheter body 2, the inner tube is inserted from the proximal end of the outer tube 22.
The proximal end of 21 projects to the catheter proximal side, the proximal end of the outer tube 22 is connected to the inside of the injection port 32, and the proximal end of the inner tube 21 is connected to the inside of the guide wire port 31.

The proximal end of the inner pipe 21 is clamped and fixed to the hub 3 by a tubular stopper 33 fitted in the first lumen 23 of the inner pipe 21. The proximal end of the stopper 33 is tapered (expanded) so that the guide wire 50 can be easily introduced into the first lumen 23.

A reinforcing tube body (tube body) 5 for preventing bending and twisting of the catheter body 2 is fitted into the opening of the distal end portion 34 of the hub 3, and the catheter body 2 is inserted inside the reinforcing tube body 5. The base end of the outer tube 22 and the base end of the reinforcing tube body 5 are inserted so as to substantially coincide with each other. By installing the reinforcing tube body 5 as described above, the first and second portions due to bending and twisting of the catheter body 2
The lumens 23 and 24 are prevented from being blocked.

The hub 3 and the reinforcing tube body 5, and the reinforcing tube body 5 and the outer tube 22 are tightly sealed by themselves or by an adhesive or the like, and are sealed without a gap, so that the expansion body 25 expansion fluids do not leak.

As the constituent material of the hub 3, for example, polyethylene, polypropylene, polycarbonate, polyamide, polysulfone, polyarylate, methacrylate-butylene-
Examples include various resins such as styrene copolymers.

Examples of the reinforcing tube body 5 include a tube body made of various resins such as crosslinked polyolefin and silicone rubber, a coil-like body made of a hard material such as metal (for example, stainless steel), or a combination thereof. .

The length of the reinforcing tube body 5, which depends on its strength, is preferably 10 to 100 mm, particularly 20 to 60 mm longer than the tip of the gripping shaped portion 4 described later.

A gripping shape portion 4 is provided at the tip of the hub 2. The gripping shape portion 4 is positively provided to facilitate gripping of the catheter 1.

The grasping shaped portion 4 is formed by attaching a member having a through passage 41 through which the reinforcing tube body 5 is inserted to the substantially central portion thereof.
With the reinforcing tube body 5 inserted through the base 2, the base end portion of the reinforcement tube body 5 is inserted into the outer periphery of the tip end portion 34 of the hub 2. In this case, the gripping shape portion 4 is configured as a member different from the hub 2, and is detachably attached to the hub 2.

The gripping shape portion 4 which is a separate member may be fixed to the hub 2 with, for example, an adhesive or a solvent. Also,
The gripping shape portion 4 is integrally formed with the hub 2,
In other words, it may be configured as a part of the hub 2.

As shown in FIG. 3, the cross-sectional shape of the gripping shape portion 4 is
For example, it is preferably a polygonal shape of about 3 to 16 polygons (a regular dodecagon in the illustrated example). As a result, the gripping shape portion 4
This is because a sense of stability is generated when gripping, and slippage can be prevented.

In the present invention, the cross-sectional shape of the gripping shape portion 4 is not limited to the polygonal shape, and may be a circular shape, an elliptical shape, or another shape.

Further, as a means for preventing slippage when gripping the gripping shape portion 4, a concave portion or a convex portion (not shown) may be formed on the outer peripheral portion of the gripping shape portion 4.

The concave portion or the convex portion may be a linear one extending in the axial direction of the catheter body 2, an annular one formed along the circumferential direction of the grasping shaped portion 4, or a spiral one. Further, the concave portions or the convex portions may be spot-shaped (dotted) arranged in a predetermined distribution on the outer peripheral portion of the grasping shaped portion 4.

The size of the gripping shape portion 4 depends on the size of the user's hand, but it is preferable that the size of the gripping shape portion 4 be within a range in which it can be securely gripped.

That is, the length of the gripping shape portion 4 is preferably about 30 to 100 mm. If the length is less than 30 mm, it becomes difficult to surely hold it, and if it exceeds 100 mm, the handling becomes inconvenient.

Further, the outer diameter (average) of the gripping shaped portion 4 is preferably 5 to 35 mm, and particularly preferably 10 to 20 mm.

If the outer diameter is outside this range, it will be difficult to grip.

The outer diameter of the gripping shape portion 4 may change continuously or stepwise along the longitudinal direction of the gripping shape portion 4.

Examples of the constituent material of the gripping shape portion 4 include polyethylene, polypropylene, polycarbonate, polyamide,
Various resins such as polysulfone, polyarylate, methacrylate-butylene-styrene copolymer, various natural or synthetic rubbers such as silicone rubber, latex rubber, butadiene rubber, metals such as stainless steel and aluminum, various glasses, various kinds of alumina, silica, etc. Ceramics, or any combination of two or more of these may be mentioned.

When the gripping shape portion 4 is made of rubber as described above, or when a rubber grip member is attached to the outer peripheral portion of the gripping shape portion 4, slipping can be prevented by itself. .

As described above, the catheter of the present invention has been described as a catheter for PTCA for expanding an intravascular stricture, but not limited to this, for example, a catheter for intracoronary thrombolysis (PTCR), a cerebral blood vessel, a hepatic blood vessel, etc. Any catheter, such as an embolization catheter or various superselective vascular catheters, which guides the tip by operating a guide wire may be used.

Further, in the present invention, the configurations of the catheter main body and the hub differ depending on the type and form of the catheter. For example,
A catheter body that does not have an expander at its tip, a catheter body with a different number of lumens, a hub that does not have a branch, or one that has three or more branches, etc. Various forms are possible.

<Operation> Hereinafter, a method of operating the catheter shown in FIGS. 1 to 3 will be described.

First, before expanding the narrowed part of the blood vessel,
The air in the lumen 24 is extracted as much as possible and replaced with a liquid such as a contrast medium.

Next, in PTCA, after a sheath is placed in the patient's blood vessel by, for example, the Seldinger method, a guiding catheter is inserted and fixed through a seal, and the guide wire 6 is firstly attached.
The distal end portion of the catheter main body 2 inserted into the lumen 23 is inserted into the blood vessel through the lumen of the guiding catheter. At this time, the guide wire 6 projects from the tip of the catheter body 2 by about 5 to 50 mm.

Next, while observing the positions of the guide wire 6 and the distal end of the catheter body 2 under fluoroscopy, the catheter 1 is gradually inserted toward the target site (stenosis). At this time, the guide wire 6 and the catheter body 2 are alternately advanced while the guide wire 6 is advanced.

The procedure at the proximal end of the catheter to do this is as follows.

As shown in FIG. 4, while grasping the grasping shaped portion 4 of the catheter 1 with the middle finger, ring finger and little finger of the left hand, pinch the guide wire 6 with the thumb and forefinger of the left hand and push it from the guide wire port 31 of the hub 3. After the guide wire 6 is pushed in for a predetermined length, the catheter body 2 is pushed in with the left hand holding the holding shape portion 4.

When the tip of the guide wire 6 reaches the bifurcation of the blood vessel, while grasping the grasping shaped portion 4 with the left hand in the same manner as above, pinch the proximal end portion of the guide wire 6 with the thumb or forefinger of the right hand, A torque is applied to the guide wire 6 to rotate the tip portion of the guide wire 6 by a predetermined angle. Since the distal end portion of the guide wire 6 is slightly curved, this rotation can direct the distal end portion of the guide wire in a desired direction, that is, in the direction of the branched blood vessel having the target site. Then, the guide wire 6 is inserted into the branch blood vessel by the same operation as the thumb and the index finger of the left hand as described above, and then the catheter body 2 is inserted into the branch blood vessel.

After selecting the bifurcation of the blood vessel in this manner, the above operation is repeated until the distal end of the catheter body 2 reaches the target site.

Next, with the expansion body 25 of the catheter body 2 positioned in the stenosis, a predetermined amount of expansion fluid such as a contrast medium is injected from the injection port 32 of the hub 3 and the expansion body is passed through the second lumen 24. The expansion fluid is fed into the internal space 26 of 25 to expand the expansion body 25. As a result, the stenosis is opened and blood flow is improved.

If an improvement in blood flow is recognized, the grasping shape portion 4 is grasped, the catheter 1 is pulled out from the blood vessel, and hemostasis by compression is performed.
Finish the procedure.

<Effects of the Invention> According to the catheter of the present invention, by providing the gripping shaped portion, the proximal end portion of the catheter can be gripped reliably, that is, stably. As a result, the operator can concentrate on the operation of the guide wire, and can easily and accurately operate.

Further, in the present invention, by providing the reinforcing tube body at the proximal end portion of the catheter body, the lumen is prevented from being blocked due to bending or twisting of the catheter body during operation.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing a structural example of a proximal end portion of the catheter of the present invention. FIG. 2 is an enlarged vertical sectional view showing a configuration example of the distal end portion of the catheter of the present invention. FIG. 3 is a sectional view taken along the line AA in FIG. FIG. 4 is a perspective view showing an operating state at the proximal end portion of the catheter of the present invention. FIG. 5 is a perspective view showing an operating state at a proximal end portion of a conventional catheter. Explanation of symbols 1, 11 …… Catheter 2 …… Catheter body 21 …… Inner tube 22 …… Outer tube 23 …… First lumen 24 …… Second lumen 25 …… Expansion body 26 …… Internal space 27 …… Marker 3, 13 …… Hub 31 …… Guide wire port 32 …… Injection port 33 …… Stopper 34 …… Tip part 4 …… Grip shape part 41 …… Through path 5 …… Reinforcement tube body 6 …… Guide wire

Claims (4)

[Claims] 1. A catheter having a catheter main body, which is used by being inserted into a peripheral blood vessel and has a lumen through which at least one guide wire is inserted, and a hub for supporting a proximal end portion of the catheter main body. The hub is integrally formed with the hub or is formed of a separate member, and has a gripping shape portion that is positively provided to facilitate gripping, and the catheter body is bent at the proximal end portion of the catheter body. A catheter equipped with a reinforcing tube body capable of preventing the lumen from being closed due to twisting or twisting. 2. The catheter according to claim 1, wherein the grasping shape portion has a polygonal cross-sectional shape. 3. The catheter according to claim 1, wherein the gripping shape portion has a concave portion or a convex portion for preventing slippage. 4. The gripping shape portion is formed so as to project from the hub toward the tip side of the catheter body, and the reinforcing tube body has a predetermined length from the gripping shape portion to the tip side of the catheter body. The catheter according to any one of claims 1 to 3, which is mounted so as to protrude.