JPH05345031A - Catheter - Google Patents

Abstract

PURPOSE:To provide a catheter easy to insert with a simple operation by enabling the bending of a tip part freely in a blood vessel according to the position of injection of a contrast medium and a medicine. CONSTITUTION:A fine through hole 8 is arranged on a tube wall of the body 1 of a catheter with a tip part thereof made soft very much from the tip to a base end part. Filament body 10 is inserted and the tip thereof is fixed at the tip of the catheter body 1 while the tail end part thereof is pulled outside at the base end part of the fine through hole 8. When the filament body 10 is pulled, the tip part is bent with the insertion side thereof inside.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a catheter for inserting a blood vessel into a blood vessel for injecting a contrast agent for diagnosis and treatment.

[0002]

2. Description of the Related Art It is well known that a catheter is used for percutaneously inserting into a blood vessel to inject a contrast agent or a drug into a target site or expanding a balloon to dilate the blood vessel.

These catheters are designed to push the distal end to a target site by pushing it into the blood vessel from outside the body, and the propulsive force applied to the proximal end is absorbed by bending or compression in the middle to smoothly advance the distal end. In order to avoid the inconvenience of not being able to do so, a thin single layer is made to have a considerable hardness as a double layer or a thick single layer up to the tip, so that the tip does not hit the blood vessel wall and damage it. As a general rule, the configuration is made to have sufficient flexibility.

On the other hand, regarding the position where the contrast medium or the drug is injected, there is no problem when the injection position is in front of the insertion direction of the catheter in the advancing direction in the blood vessel, but it may be bent to the side or folded. In many cases, there is an injection position at a curved position, and for this reason, it is necessary to prepare many types of catheters with tip parts formed in various bending shapes according to the injection position, which is troublesome to manage and costly. Is disadvantageous.

Further, the bent portion of the tip has a certain degree of hardness so as not to be linearly deformed by the injection pressure of a contrast medium or a drug, but along the guide wire previously inserted and left in the blood vessel. It is difficult to obtain a catheter that satisfies all of the flexibility to the extent that it does not damage the blood vessel, the hardness to maintain the bent shape, and the ease of insertion, because the resistance when pushing and inserting it by pushing is large. Is.

Further, when a catheter having a bent portion at the tip is inserted up to a predetermined portion, the bent portion is oriented in a random direction, and therefore, the proximal portion is held to close the tip toward the injection position. It is easy to get caught in the blood vessel wall when it is rotated, so that it is necessary to repeat the procedure of advancing or retracting, removing the catch and rotating it again, which is extremely troublesome to operate.

[0007]

SUMMARY OF THE INVENTION The problem to be solved by the present invention is that the catheter whose tip portion is pre-bent must be prepared in many types, which is troublesome to manage and disadvantageous in terms of cost. Also the flexibility of the bent part,
It is difficult to make the hardness appropriate, and in addition to that, the operation of accurately opening the tip toward the injection position is extremely troublesome.

[0008]

In order to solve the above-mentioned problems, the present invention firstly provides a narrow wall through a distal end portion to a proximal end portion in a tube wall of a catheter body having a highly flexible distal end portion. The linear body is inserted, the distal end of the linear body is fixed to the distal end of the catheter body, and the tail end is pulled out from the proximal end of the narrow hole.

Secondly, the present invention secondly provides a plurality of narrow holes extending from the distal end to the proximal end in the tube wall of the catheter body having a highly flexible distal end side by side in the circumferential direction, and has two or more linear lines. The body is inserted, each tip of this filament is fixed to the tip of the catheter body, and the tail end of each is drawn out from the base end of the through hole.

[0010]

[Function] When the tail end of the striatum is pulled by inserting it to a predetermined site in the blood vessel by the same operation means as before, the fixed part of the tip is pulled toward the base end, and the highly flexible tip is drawn linearly. The insertion side of the strip is curved inward and bent according to the tensile strength. When two or more filaments are inserted side by side in the circumferential direction, one of them can be pulled or the tensile strength of the two or more filaments can be changed to bend in various directions.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings. FIGS. 1 and 2 show an embodiment of the first invention, in which a catheter body 1 is an inner tube 2 made of a soft synthetic resin. The outer tube 3 made of a hard synthetic resin is closely coated except for the tip portion thereof, and the portion covered with the outer tube 3 forms a shut portion 4 having a considerable hardness and the tip of the outer tube 3 is formed. The part has a taper portion 5 that is gently inclined toward the tip so that the tip is equal to the outer diameter of the inner tube 2, and the inner tube 2 at the tip is exposed. Forms a sufficiently flexible movable part 6.

The main through hole 7 penetrating in the front and rear of the inner pipe 2 has its center at a position eccentric from the central axis, and one thin through hole is formed in the thick portion of the pipe wall from the tip to the base end. 8 is the main passage 7
It is formed in parallel with.

The proximal end portion of the catheter body 1 is fitted into a protective tube 15 made of a hard synthetic resin and connected to the outlet side of a cock 17 by a pipe joint 16. When the cock 17 is opened, a contrast agent or a drug is mainly supplied. It is injected into the target location of the blood vessel through the through hole 7.

Further, a filament 10 made of synthetic resin monofilament thread is inserted into the narrow hole 8, and a short cylindrical stopper 11 provided at the tip thereof is closely fitted to the tip of the through hole 8. Is fixed to the distal end of the catheter body 1, and the tail end is pulled out to the outside from a side hole 9 that communicates with the proximal end of the narrow hole 8 from the protective tube 15 through the outer tube 3 and has an annular knob. 12 is attached.

In this embodiment having such a structure, the same operation means as that of the conventional catheter is used to insert a predetermined portion in the blood vessel, and the tip portion of the outer tube 3 is the tapered portion 5 having no step. The shaft portion 4 can be inserted into a blood vessel without damaging or peeling off the blood vessel wall, and the flexible movable portion 6 can be smoothly advanced by the propulsive force applied to the proximal end portion because the shaft portion 4 is considerably hard and the blood vessel It bends easily along the curved portion of the body and does not impinge on and damage the vessel wall.

Further, since the movable portion 6 is flexible and can be arbitrarily curved without being bent in advance, it can be advanced along the guide wire with a small force.

When the distal end reaches the target portion in this way, when the knob 12 is pinched by the fingertip and pulled, the filamentous body 10 is tensioned and the highly flexible movable portion 6 tries to be pulled toward the proximal end side. At this time, the fixed part by the stopper 11 is the movable part 6
Is a portion near the outer peripheral edge of the movable body 6, and as a result of the pulling force in the proximal direction acting on this eccentric position, the movable portion 6 is curved inward on the side where the linear body 10 is inserted (see FIG. 3). ).

The radius of the bend and the opening direction of the tip depend on the tensile strength of the filament 10 and the length of the movable portion 6,
The portion covering the outer tube 3 is hardly curved.

Since the movable portion 6 of the catheter of this embodiment is curved toward the insertion side of the linear body 10 and can be bent only in one direction, it can be bent toward the injection position when reaching the target site. Need to be rotated, but striatum 1
By pulling 0 and advancing it little by little while curving it gradually, it is possible to smoothly insert it into the blood vessel branched laterally and to close the tip at the injection position without getting caught.

FIGS. 4 and 5 show different embodiments of the second invention. The catheter body 21 of the embodiment of FIG. 4 has an inner tube 22 having a main through hole 27 concentric with the central axis. The three narrow holes 28 are provided at equal intervals in the circumferential direction from the tip to the base end, and the inner tube 22 is closely covered with the outer tube 23 except for the tip and the tip of the outer tube 23 is covered. The taper portion has the same outer shape as that shown in FIG.

A filament 30 made of a synthetic resin monofilament yarn is inserted into each of the three fine holes 28, and the tip end of the catheter body 21 is formed by the same means as shown in FIG. The tail end is pulled out from the base end of the narrow hole 28 to the outside.

The catheter body 41 of the embodiment shown in FIG. 5 has a highly flexible tube member 42 having a main through hole 47 concentric with the central axis.
The tube member 42 has a uniform outer diameter and has five narrow holes 48a, 48b, 48c, 48c, 48c on the tube wall from the tip to the base end. The configuration is such that they are provided at substantially equal intervals in the circumferential direction.

A core material 51 made of a metal or a hard synthetic resin for reinforcement is inserted into one narrow hole 48a over the region covered with the outer tubes 3 and 23 shown in FIGS. As a result, the tube member 42 has a considerable hardness. Another narrow hole 48b is used as a passage for a balloon inflating fluid as seen in Japanese Patent Publication No. 2-949. The filaments 50 made of a synthetic resin monofilament are respectively inserted into the remaining three narrow holes 48c, and the tips are fixed to the tips of the catheter body 41 by the same means as shown in FIG. The tail end is pulled out from the base end of the narrow hole 48c.

In each of these embodiments, the catheter is inserted to a predetermined site in the blood vessel by the same operation means as the conventional catheter, and any one or two of the three filaments 30, 50 are inserted. By pulling, the highly flexible tip can be bent in any direction, and at that time there is no need to rotate to match the bending direction with the injection position, so operation is easier than in the first invention. is there.

The narrow holes 8, 28, 48c for the filaments 10, 30, 50 may be specially provided, but those previously provided for a fluid passage for a balloon, a passage for a fiberscope, etc. It goes without saying that the filaments 30 and 50 are not limited to three in the second invention.
Further, the tips of the filaments 10, 30, 50 can be fixed to the tips of the catheter bodies 1, 21, 41 by using an adhesive or by welding.

[0026]

EFFECTS OF THE INVENTION The catheter of the present invention has a structure in which a linear body is inserted into the tube wall of a catheter body having a highly flexible distal end, is fixed to the distal end, and the tail end is pulled to bend the distal end. Therefore, it is not necessary to bend the tip in advance, and it is possible to easily insert it into a predetermined part of the blood vessel.
Even if the injection position of the contrast agent or drug is inside a branched blood vessel and is bent at the side and further in the folding direction, it is possible to bend it at an arbitrary radius and direct the tip in an arbitrary direction by pulling the striatum. Therefore, it is possible to smoothly close the injection position without being caught on the blood vessel wall.

Since it can be bent into various shapes in the blood vessel as described above, there are advantages that the types of catheters can be greatly reduced, the management can be simplified, and the cost can be reduced.

Furthermore, when a plurality of filaments are arranged in the circumferential direction, it is possible to bend in various directions without the need to rotate the catheter body so that the filaments can be bent toward the injection position, and the operation is much easier. Is.

[Brief description of drawings]

FIG. 1 is a front view in which a part of an embodiment of the first invention is cut away and a part is shown in an enlarged cross section.

FIG. 2 is an enlarged cross-sectional view of FIG.

FIG. 3 is a partial front view showing a state in which the tip portion of FIG. 1 is bent.

FIG. 4 is a sectional view of an embodiment of the second invention.

FIG. 5 is a sectional view of a different embodiment of the second invention.

[Explanation of symbols]

1,21,41 catheter body, 8,28,48c
Narrow hole, 10, 30, 50 Striatum,

Claims (2)

[Claims] 1. A narrow wall is provided in a tube wall of a catheter body having a highly flexible distal end portion from a distal end to a proximal end portion, and a linear body is inserted through the narrow hole. The distal end of the linear body is fixed to the distal end of the catheter body, and the tail end portion is pulled out from the proximal end portion of the narrow hole to the outside. 2. A plurality of through holes extending from the distal end to the proximal end are provided side by side in a circumferential direction on a tube wall of a catheter body having a highly flexible distal end, and two or more of these through holes are provided. A linear body is inserted through the distal end of the linear body, and the distal end of the linear body is fixed to the distal end of the catheter body, and the tail end portion of the linear body is pulled out from the proximal end portion of the narrow hole. A catheter characterized by: