WO2012042709A1

WO2012042709A1 - Catheter

Info

Publication number: WO2012042709A1
Application number: PCT/JP2011/003520
Authority: WO
Inventors: 謙二森; 拓也桝田
Original assignee: 日本ライフライン株式会社
Priority date: 2010-09-28
Filing date: 2011-06-21
Publication date: 2012-04-05
Also published as: HK1184401A1; JP4897077B1; JP2012070882A; CN103124577A; KR20130041818A; KR101455494B1; CN103124577B

Abstract

A catheter (2) provided with: a flexible tubular member (4) with a plurality of lumens formed along the axis thereof; a first control wire (40) inserted into a first lumen, which is one of the aforementioned plurality of lumens; and a second control wire (42) inserted into a second lumen, which is another of the aforementioned plurality of lumens. The tubular member (4) curves in a first direction when the first control wire (40) is pulled and curves in a second direction when the second control wire (42) is pulled. At least parts of the curved region (N) formed when the tubular member curves in the first direction and the curved region (M) formed when the tubular member curves in the second direction are offset along the axis of the tubular member (4). When the tubular member curves in the first direction, a straight region (O) of a prescribed length is formed from the distal end of the tubular member (4), and the aforementioned curved region (N) is formed proximal to said straight region (O).

Description

catheter

The present invention relates to a catheter. More specifically, the present invention relates to a catheter capable of easily changing the direction of the vicinity of the distal end inserted into the body cavity by operating the operation portion on the proximal end side arranged outside the body. .

In a catheter such as an electrode catheter inserted through a blood vessel and into the heart, the orientation of the distal end (tip) of the catheter inserted into the body is the proximal end (proximal end or proximal side) of the catheter placed outside the body. It is deflected by operating the operation unit mounted on the. In order to smoothly insert the catheter into a desired site such as the inside of the heart, the vicinity of the distal end of the catheter is required to be bendable with a predetermined curve shape.

In a so-called multi-lumen catheter in which a plurality of lumens are formed along the axial direction, conventionally, an operation wire is inserted into the lumen formed at a position shifted from the central axis of the catheter. Then, by pulling the operation wire in the operation part, the direction of the distal end is deflected by curving the vicinity of the distal end of the catheter in the eccentric direction of the lumen, that is, the side displaced from the central axis of the tubular member. (See Patent Document 1).

JP 2000-288095 A

There is always a demand to improve the operability of the catheter in order to cope with more advanced catheterization. For example, as a treatment or examination of the heart, a catheter is inserted through the femoral vein, approached from the inferior vena cava to the coronary sinus, and the tip of the catheter curved along the inner wall of the coronary sinus reaches the great heart vein It has been known. In such catheterization, there is a demand for increasing variations in the curved shape of the catheter tip so that the catheter can be easily passed through a complicated route.

The present invention has been made in view of these problems, and an object thereof is to provide a technique capable of increasing variations in the curved shape of the catheter tip.

One embodiment of the present invention is a catheter. The catheter includes a flexible tubular member having a plurality of lumens formed along the axial direction, a first operation wire inserted through the first lumen of the plurality of lumens, and a second of the plurality of lumens. The tubular member is bent in the first direction when the first operating wire is pulled, and is second when the second operating wire is pulled. The first curved region formed when bent in the first direction and the second curved region formed when bent in the second direction are at least partially shifted in the axial direction of the tubular member. And a straight region is formed in a predetermined range from the distal end of the tubular member when bent in the first direction, and the first curved region is formed on the proximal side of the straight region. .

According to this aspect, the variation of the curved shape of the catheter tip can be increased.

In the catheter of the above aspect, the first curved region and the second curved region may have different minimum radii of curvature. The straight region may have a length of 3 to 15 mm.

In the catheter of the above aspect, the distal end of the first manipulation wire is fixed between the distal end and the proximal end of the tubular member, and the distal end of the second manipulation wire is at the distal end. It may be fixed at the distal end of the tubular member.

In the catheter of the above aspect, the catheter is provided between the distal end and the proximal end of at least one of the first manipulation wire and the second manipulation wire, and the at least one manipulation wire is inserted therethrough. A hollow portion having an inner diameter smaller than the inner diameter of the lumen is provided at a predetermined position of a restraining member provided so that the at least one manipulation wire can be inserted, and at least one manipulation wire distal to the restraining member. A detent portion having an outer diameter larger than the inner diameter of the portion, and when the at least one operation wire is pulled, the portion distal to the detent portion of the at least one operation wire is It may be restrained in a region distal to the restraining member.

In the catheter of the above aspect, when the detent portion is restrained by the restraining member, the radius of curvature of the tubular member proximal to the restraining member may be smaller than the radius of curvature of the tubular member distal to the restraining member.

According to the present invention, variations in the curved shape of the catheter tip can be increased.

1A is a schematic side view of the catheter according to the first embodiment, and FIG. 1B is a schematic top view of the catheter according to the first embodiment. FIG. 2 is a schematic cross-sectional view taken along line AA in FIGS. 1 (A) and 1 (B). It is a schematic sectional drawing on the BB line of FIG. 1 (A). 3 is a schematic cross-sectional perspective view of the vicinity of a wire fastening member of the catheter according to Embodiment 1. FIG. FIGS. 5A and 5B are schematic cross-sectional views showing the shape of the distal end portion of the catheter when the first operation wire and the second operation wire are pulled. 6 is a schematic cross-sectional view of the vicinity of a restraining member of a catheter according to Embodiment 2. FIG. It is a cross-sectional schematic diagram which shows the shape of the front-end | tip part of a catheter when pulling operation of the 2nd operation wire. It is a cross-sectional schematic diagram which shows the shape of the front-end | tip part of a catheter when pulling operation of the 2nd operation wire.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all the drawings, the same reference numerals are given to the same components, and the description will be omitted as appropriate.

(Embodiment 1)
The catheter according to the first embodiment is an electrode catheter capable of tip deflection operation, for example, diagnosis or treatment of arrhythmia in the heart, in particular, an abnormal conduction system that causes arrhythmia using a heat source such as high frequency from within the heart chamber. It is suitably used for catheter ablation (myocardial ablation) for cauterization.

FIG. 1A is a schematic side view of the catheter according to the first embodiment, and FIG. 1B is a schematic top view of the catheter according to the first embodiment. As shown in FIG. 1 (A) and FIG. 1 (B), the catheter 2 according to Embodiment 1 includes a tip tip electrode 10 and ring-

shaped electrodes

12a and 12b (hereinafter referred to as appropriate) at the distal end of the tubular member 4. The

ring electrodes

12a and 12b are collectively referred to as “ring electrode 12”). The tip electrode 10 is fixed to the tubular member 4 by, for example, an adhesive or melt bonding. The ring-

shaped electrodes

12 a and 12 b are fixed to the outer peripheral surface of the tubular member 4 by caulking a metal ring having a diameter larger than the outer diameter of the tubular member 4, for example. The number of ring-shaped electrodes 12 is not particularly limited, and can be appropriately set according to the number of conducting wires that can be inserted into the tubular member 4.

An operation handle 6 is attached to the proximal end portion of the tubular member 4. From the handle 6, lead wires of lead wires electrically connected to the tip electrode 10 and the

ring electrodes

12a and 12b are drawn out. The handle 6 is equipped with a knob 7 for performing a deflection movement operation (swing operation) of the distal end portion of the tubular member 4.

The tubular member 4 has a hollow structure having a plurality of lumens formed along the axial direction as will be described later, and is constituted by an inner cylinder member and an outer cylinder member (see FIG. 2). It is preferable that the tubular member 4 has relatively high flexibility (softness) on the distal side and relatively low flexibility on the proximal side. For example, the outer cylinder member is configured by connecting members I to III in order from the distal end side. The members I to III are highly flexible in this order. For example, the range of Shore D hardness of member I is 20 to 63, the range of Shore D hardness of member II is 45 to 72, and the range of Shore D hardness of member III is 55 to 80. Thereby, the tubular member 4 can be configured so that the flexibility on the distal side is high and the flexibility on the proximal side is low. The tubular member 4 may have a structure in which an inner cylinder member and an outer cylinder member are integrated. In addition, the tubular member 4 may have a multilayer structure of the inner cylinder member and / or the outer cylinder member.

The main part of the tubular member 4 is made of a synthetic resin such as polyolefin, polyamide, polyether polyamide, or polyurethane. The outer diameter of the tubular member 4 is generally about 0.6 to 3 mm, and the length is about 500 to 1200 mm. As will be described later, through the lumen formed in the axial direction of the tubular member 4, conductive wires connected to the tip electrode 10 and the

ring electrodes

12 a and 12 b are passed in an insulated state.

The tip electrode 10 and the ring electrode 12 are made of a metal having good electrical and thermal conductivity, such as aluminum, copper, stainless steel, gold, platinum, and the like. Note that the tip electrode 10 and the ring-shaped electrode 12 are preferably made of platinum or the like in order to provide a good contrast property for X-rays. The outer diameters of the tip electrode 10 and the ring electrode 12 are not particularly limited, but are preferably about the same as the outer diameter of the tubular member 4 and are usually about 0.5 to 3 mm.

FIG. 2 is a schematic cross-sectional view taken along the line AA in FIGS. 1 (A) and 1 (B). FIG. 3 is a schematic cross-sectional view along the line BB in FIG. FIG. 4 is a schematic cross-sectional perspective view of the vicinity of the wire fastening member of the catheter according to the first embodiment. In FIG. 4, the outer cylinder member 4 b and the inner cylinder member 4 a distal to the wire fastening member 100 are omitted. FIG. 4 shows a state where the inner cylinder member 4a is bent in the X1 direction shown in FIG. 1 (B).

As shown in FIGS. 2 to 4, the tubular member 4 includes an inner cylinder member 4a having a plurality of lumens and an outer cylinder member 4b covering the inner cylinder member 4a. The inner cylinder member 4a extends over a predetermined distance from the distal end portion of the outer cylinder member 4b (see FIGS. 5A and 5B). For example, the length of the inner cylinder member 4a is 20 to 1200 mm, and the length of the outer cylinder member 4b is 500 to 1200 mm. The outer peripheral surface of the inner cylinder member 4a and the inner peripheral surface of the outer cylinder member 4b are fixed in close contact with each other. For fixing the inner cylinder member 4a and the outer cylinder member 4b, methods such as adhesion and welding can be used.

The tubular member 4 has a blade (see FIGS. 5A and 5B) as a reinforcing member for increasing the rigidity of the tubular member 4 in a region proximal to the proximal end of the inner tubular member 4a. Is provided. Thereby, when the 1st operation wire 40 and the 2nd operation wire 42 are pulled, it can prevent that the proximal side rather than the inner cylinder member 4a of the tubular member 4 curves. The blade is embedded in, for example, the outer cylinder member 4b. The blade can be formed of a metal such as stainless steel, tungsten, gold, titanium, silver, copper, platinum, or iridium, or an alloy of these metals. The blade may also be formed of a non-metallic material such as polyparaphenylene terephthalamide fiber, liquid crystal polymer fiber or glass fiber, polyether ether ketone, polyamide 66, and the like.

In the inner cylinder member 4a, a first lumen 21, a second lumen 22, a third lumen 23, a fourth lumen 24, a fifth lumen 25, and a sixth lumen 26 are formed along the axial direction. Further, a leaf spring 30 is embedded in the inner cylinder member 4a at a position passing through the central axis. The leaf spring 30 is an elastic plate-like body extending along the axial direction of the tubular member 4, the distal end thereof extending to the distal end portion of the inner cylinder member 4 a, and the proximal end of the inner cylinder member 4 a. Extends to the proximal end. The flatness in the curved region of the tubular member 4 can be enhanced by the leaf spring 30.

The first lumen 21 is provided at a position facing the second lumen 22 with the leaf spring 30 interposed therebetween, in other words, with the central axis of the tubular member 4 interposed therebetween. That is, the first lumen 21 and the second lumen 22 are provided at positions shifted from the central axis of the tubular member 4. The third lumen 23 is provided at a position facing the fifth lumen 25 across the central axis of the tubular member 4, and the fourth lumen 24 is opposed to the sixth lumen 26 across the central axis of the tubular member 4. It is provided in the position to do. In the present embodiment, a line connecting the central axis of the first lumen 21 and the central axis of the second lumen 22, a line connecting the central axis of the third lumen 23 and the central axis of the fifth lumen 25, and the fourth lumen 24 A line connecting the central axis and the central axis of the sixth lumen 26 is arranged to intersect each other at the central axis position of the tubular member 4. The diameters of the first lumen 21 and the second lumen 22 are, for example, about 0.1R to 0.60R, where R is the diameter of the tubular member 4. The diameters of the third lumen 23 to the sixth lumen 26 are, for example, about 0.1R to 0.60R, where R is the diameter of the tubular member 4.

A wire fastening member 100 is provided at a predetermined position of the tubular member 4 as an intermediate member. In this embodiment, the inner cylinder member 4a is divided into two at a predetermined position, and the wire fastening member 100 is disposed between the two inner cylinder members 4a. The wire fastening member 100 is in contact with the distal end of the inner cylinder member 4 a proximal to the wire fastening member 100 and the proximal end of the inner cylinder member 4 a distal to the wire fastening member 100. . Examples of the material constituting the wire fastening member 100 include liquid crystal polymer and stainless steel. The wire fastening member 100 has an outer diameter substantially equal to that of the inner cylinder member 4a, and the outside of the wire fastening member 100 is covered with the outer cylinder member 4b.

In the wire fastening member 100, a hollow portion 101 having an inner diameter smaller than the inner diameter of the first lumen 21 is provided along the axial direction of the catheter 2 corresponding to the first lumen 21. The inner diameter of the hollow portion 101 is larger on the distal side than the proximal side, the inner diameter on the proximal side is substantially equal to the outer diameter of the first operation wire 40 described later, and the inner diameter on the distal side is described later. It is approximately equal to the outer diameter of the stop member 110. The opening on the proximal side of the hollow portion 101 is opposed to the opening on the distal side of the first lumen 21 provided in the inner cylinder member 4 a closer to the wire fastening member 100.

Further, the wire fastening member 100 is provided with a hollow portion 102 having an inner diameter equivalent to the inner diameter of the second lumen 22 along the axial direction of the catheter 2 corresponding to the second lumen 22. The opening on the proximal side of the hollow portion 102 faces the opening on the distal side of the second lumen 22 provided in the inner cylinder member 4 a closer to the wire fastening member 100. Further, the opening on the distal side of the hollow portion 102 is opposed to the opening on the proximal side of the second lumen 22 provided in the inner cylinder member 4 a on the distal side of the wire fastening member 100. Accordingly, the second lumens 22 of the two inner cylindrical members 4a arranged on both sides of the wire fastening member 100 communicate with each other with the hollow portion 102 interposed therebetween, and the second operation described later with the two second lumens 22 and the hollow portion 102 is performed. The wire 42 can be inserted.

Further, the wire fastening member 100 is provided with a hollow portion 103 and a hollow portion 106 along the axial direction of the catheter 2 corresponding to the third lumen 23 and the sixth lumen 26, respectively. The inner diameters of the hollow portion 103 and the hollow portion 106 are equal to the inner diameters of the third lumen 23 and the sixth lumen 26, respectively. The proximal and distal openings of the hollow portion 103 and the hollow portion 106 are aligned with the third lumen 23 and the sixth lumen 26 of the two inner cylindrical members 4 a disposed on both sides of the wire fastening member 100. Yes. As a result, a conductor 74 described later can be inserted into the two third lumens 23 and the hollow portion 103, and a conductor 72 described later can be inserted into the two sixth lumens 26 and the hollow portion 106.

Also, the wire fastening member 100 is provided with a hollow portion (not shown) along the axial direction of the catheter 2 corresponding to each of the fourth lumen 24 and the fifth lumen 25. The inner diameter of each hollow portion is equal to the inner diameter of the fourth lumen 24 and the fifth lumen 25, respectively. Openings on the proximal side and the distal side of each hollow portion are aligned with the fourth lumen 24 and the fifth lumen 25 of the two inner cylinder members 4 a arranged on both sides of the wire fastening member 100. Thereby, an arbitrary conducting wire or the like can be inserted through the two fourth lumens 24 and the corresponding hollow portions, and a conducting wire 70 described later can be inserted through the two fifth lumens 25 and the corresponding hollow portions.

The first operation wire 40 is slidably inserted into the first lumen 21, and the second operation wire 42 is slidably inserted into the second lumen 22. The first manipulation wire 40 extends from the proximal end of the tubular member 4 to the wire clamp member 100, and the second manipulation wire 42 extends from the proximal end of the tubular member 4 to the distal end. is doing. The length of the first operation wire 40 is about 490 to 1190 mm, and the length of the second operation wire 42 is about 500 to 1200 mm.

A locking member 110 is provided at the distal end of the first operation wire 40. The outer diameter of the locking member 110 is equivalent to the inner diameter on the distal side of the hollow portion 101 and is larger than the inner diameter on the proximal side of the hollow portion 101. The locking member 110 is made of the same material as the first operation wire 40 or a different material, and is provided in a ring shape around the first operation wire 40. The method of providing the locking member 110 around the first operation wire 40 is not particularly limited, and examples thereof include solder bonding, a crimping method by caulking, and fusion. The locking member 110 may be integrally formed of the same material as the first operation wire 40. The first operation wire 40 has its distal end connected to the wire fastening member 100 by fixing the outer peripheral surface of the locking member 110 to the inner peripheral surface of the hollow portion 101 with an adhesive. Accordingly, the first operation wire 40 is fixed to the tubular member 4 via the locking member 110 at the distal end portion between the distal end portion and the proximal end portion of the tubular member 4. The proximal end portion of the first operation wire 40 is connected to a knob 7 shown in FIGS. 1 (A) and 1 (B). As a result, the catheter 2 can operate the knob 7 to pull the first operation wire 40 and swing the distal end thereof in the direction of the arrow X1 (the first direction) in FIG. 1B. Yes. The method of fixing the distal end portion of the first operation wire 40 to the wire fastening member 100 is not limited to bonding the outer peripheral surface of the locking member 110 and the inner peripheral surface of the hollow portion 101, and the locking member 110. A method of pressing the locking member 110 into the hollow portion 101 by making the outer diameter slightly larger than the inner diameter on the distal side of the hollow portion 101 may be employed.

An anchor 42 a having a larger diameter than the main body of the second operation wire 42 is formed at the distal end portion of the second operation wire 42. A recess 50 is formed inside the tip electrode 10, and the recess 50 is filled with solder 60. The second operation wire 42 is connected to the vicinity of the distal end of the tubular member 4 by being embedded in the solder 60 and being fixed to the solder 60 and the tip electrode 10. Therefore, the distal end of the second operation wire 42 is fixed to the tubular member 4 via the solder 60 and the tip electrode 10 at the distal end of the tubular member 4. Further, the proximal end portion of the second operation wire 42 is fixed to the knob 7. As a result, the catheter 2 can operate the knob 7 to pull the second operation wire 42 and swing the distal end thereof in the direction of the arrow X2 (second direction) in FIG. 1B. Yes. In the present embodiment, since the anchor 42 a is provided at the distal end portion of the second operation wire 42, the distal end portion of the second operation wire 42 is difficult to come out of the solder 60. Thereby, the operation reliability of the catheter 2 can be improved.

The conducting wire 70 is inserted through the fifth lumen 25. The distal end of the conductor 70 is embedded in the solder 60 (not shown). Thereby, the conducting wire 70 and the tip chip electrode 10 are electrically connected via the solder 60.

In addition, a conducting wire 72 is inserted through the sixth lumen 26. The distal end portion of the conducting wire 72 is fixed to the ring-shaped electrode 12 a through an opening (not shown) formed in the tubular member 4. The distal end portion of the conducting wire 72 is fixed to the ring-shaped electrode 12a using, for example, welding or soldering. Thereby, the conducting wire 72 and the ring-shaped electrode 12a are electrically connected.

Further, a conducting wire 74 is inserted through the third lumen 23. The distal end portion of the conducting wire 74 is fixed to the ring-shaped electrode 12 b through an opening (not shown) formed in the tubular member 4. The distal end portion of the conducting wire 74 is fixed to the ring-shaped electrode 12b using, for example, welding or soldering. Thereby, the conducting wire 74 and the ring-shaped electrode 12b are electrically connected.

FIG. 5 (A) and FIG. 5 (B) are schematic cross-sectional views showing the shape of the distal end portion of the catheter when the first operation wire and the second operation wire are pulled. FIG. 5A shows a state in which the distal end of the catheter 2 is deflected in the direction of the arrow X2 in FIG. FIG. 5B shows a state in which the distal end of the catheter 2 is deflected in the direction of arrow X1 in FIG. 5A and 5B, illustration of the first lumen 21, the second lumen 22, and the boundary line between the inner cylinder member 4a and the outer cylinder member 4b is omitted.

As shown in FIG. 5A, when the second operation wire 42 is pulled, the tubular member 4 bends in the direction of the arrow X2 in FIG. Here, the distal end portion of the second operation wire 42 is fixed to the tip electrode 10. In other words, the distal end portion of the second operation wire 42 is fixed to the distal end portion of the tubular member 4. Further, as described above, the tubular member 4 is provided with the blade 80. Therefore, the bending region M (second bending region) of the tubular member 4 formed when the second operation wire 42 is pulled is the distal end of the tubular member 4 from the proximal end portion of the inner cylindrical member 4a. Part. That is, when the tubular member 4 is bent in the direction of the arrow X2 in FIG. 1B, a predetermined range from the distal end portion of the tubular member 4 is bent.

On the other hand, as shown in FIG. 5 (B), when the first operation wire 40 is pulled, the tubular member 4 is bent in the direction of the arrow X1 in FIG. 1 (B). Here, the distal end portion of the first operation wire 40 is fixed to the wire fastening member 100. In other words, the distal end portion of the first manipulation wire 40 is fixed between the distal end portion and the proximal end portion of the tubular member 4. That is, the distal end portion of the first operation wire 40 is displaced in the axial direction of the tubular member 4 with respect to the distal end portion of the second operation wire 42. The tubular member 4 is provided with a blade 80. Therefore, the curved region N (first curved region) of the tubular member 4 when the first operation wire 40 is pulled is from the proximal end portion of the inner cylindrical member 4a to the wire fastening member 100, and the curved region N A straight region O is formed between the tube and the distal end of the tubular member 4. That is, when curved in the direction of arrow X1 in FIG. 1B, a straight region O is formed in a predetermined range from the distal end portion of the tubular member 4, and a curved region N is formed proximal to the straight region O. Is done. Therefore, when the tubular member 4 is bent in the direction of the arrow X1 in FIG. 1B and when it is bent in the direction of the arrow X2, a part of the formed curved region is shifted in the axial direction. The length of the straight region O is, for example, 5 to 15 mm.

The catheter 2 according to the present embodiment described above is formed when the catheter 2 is bent in the direction of the arrow X1 in FIG. 1B and when it is bent in the direction of the arrow X2 in FIG. The curved region M is at least partially displaced in the axial direction of the tubular member 4. Specifically, the distal end position of the curved region N and the distal end position of the curved region M are different. Then, the minimum radius of curvature of the curved region N and the minimum radius of curvature of the curved region M are different. Here, the “minimum curvature radius” is the curvature radius of each curved region when the tubular member 4 is curved to the maximum extent. Thereby, the variation of the curve shape of the catheter tip can be increased. As a result, the operability of the catheter 2 is improved, and catheterization for inserting the catheter 2 through a more complicated path can be easily performed.

Moreover, the following effects are acquired by enabling the tubular member 4 to form the left-right asymmetric curve shape like the catheter 2 which concerns on this embodiment. That is, for example, when the tip of the catheter approaches the lesion site in the blood vessel, the contact position of the catheter with the inner wall of the blood vessel can be adjusted, so that the posture of the catheter 2 can be stabilized in the blood vessel. When the lesion site is linearly cauterized, if the ablation position is at the back of the blood vessel as viewed from the catheter tip, that is, at the distal end, the tubular member 4 is curved to the side where the curvature of the curve is small. When it is proximal as viewed from the distal end, the moving distance of the distal end of the catheter when the catheter is bent can be adjusted according to the ablation position by curving the tubular member 4 to the side where the curvature of the curve is large. . Further, even when there are a plurality of lesion sites, a single catheter 2 can be used.

Further, in the catheter 2 of the present embodiment, the straight region O is formed on the distal side of the curved region N when it is bent in the direction of the arrow X2 in FIG. That is, when the catheter 2 according to this embodiment is bent in the direction of the arrow X1 in FIG. 1B, a straight region O is formed in a predetermined range from the distal end portion of the tubular member 4, and the straight region O When the curved region N is formed on the more proximal side and curved in the direction of the arrow X2 in FIG. 1B, the curved region M at least partially displaced in the axial direction of the tubular member 4 with respect to the curved region N It is formed. In this case, the following effects can be obtained. That is, for example, in an ablation procedure for an atrial flutter (AFL) case, it is frequently performed to cauterize Isthmus, which is a region between the inferior vena cava and the tricuspid valve inside the heart, in a linear manner. At this time, generally, the catheter is inserted from the inferior vena cava into the heart, and the distal end of the catheter is placed in front of the tricuspid valve. Then, cauterization is started from this state, and cauterization is performed while the catheter is pulled back, so that a cauterization line is formed in Isthmus from the tricuspid valve toward the inferior vena cava. In this ablation procedure, when Isthmus is linearly cauterized, it is preferable that the catheter has a curved shape having a linear region at the tip in terms of the ease of linear cauterization. On the other hand, when the tip of the catheter is brought into contact with the vicinity of the tricuspid valve (ventricular side), it is preferable that the catheter has a curved shape that is curved to the tip in terms of easy contact. In the catheter 2 according to the present embodiment, a linear region O is provided at the distal end of the catheter, and a shape curved proximally of the linear region O and a shape curved toward the distal end of the catheter can be formed. Both the ease of cauterization and the ease of contact can be achieved. Furthermore, the catheter 2 according to the present embodiment can switch the contact method to the lesion site by switching between a curved shape having a straight region at the distal end and a curved shape curved to the distal end. That is, it is possible to carry out vertical contact in which the catheter tip is erected and vertically contacted with the lesion site, and lateral application in which the catheter tip is laid and contacted in parallel with the lesion site.

(Embodiment 2)
In the catheter 2 according to the second embodiment, the operation wire is provided with a detent portion, the tubular member is provided with a deterring member, and the detent portion moved according to the pulling operation of the operation wire comes into contact with the deterrent member. Thus, a structure is provided in which the movement of the operation wire in the axial direction is restricted. Hereinafter, the catheter according to Embodiment 2 will be described. In addition, about the catheter which concerns on Embodiment 2, the same code | symbol is attached | subjected about the structure similar to Embodiment 1, and the description and illustration are abbreviate | omitted suitably.

FIG. 6 is a schematic sectional view of the vicinity of the restraining member of the catheter according to the second embodiment. 7 and 8 are schematic cross-sectional views showing the shape of the distal end portion of the catheter when the second operation wire is pulled.

The catheter 2 according to this embodiment is provided between the distal end and the proximal end of the second operation wire 42 and has an inner diameter smaller than the inner diameter of the second lumen 22 through which the second operation wire 42 is inserted. The small-diameter hollow portion includes a restraining member provided so that the second operation wire 42 can be inserted therethrough. In the present embodiment, as shown in FIG. 6, the wire fastening member 100 functions as a restraining member. The hollow portion 102 of the wire fastening member 100 has an inner diameter smaller than the inner diameter of the second lumen 22, and this hollow portion 102 functions as the above-described small-diameter hollow portion.

Further, the second operation wire 42 is provided with a detent portion 112 at a predetermined position distal to the wire fastening member 100 as a restraining member. The outer diameter of the detent portion 112 is larger than the inner diameter of the hollow portion 102 as a small-diameter hollow portion. Further, the outer shape of the detent portion 112 is smaller than the inner diameter of the second lumen 22. The detent portion 112 is made of the same material as the second operation wire 42 or a different material, and is provided in a ring shape around the second operation wire 42. The method of providing the movement stopper 112 around the second operation wire 42 is not particularly limited, and examples thereof include solder bonding, a crimping method by caulking, and fusion. The detent portion 112 may be integrally formed of the same material as the second operation wire 42.

As shown in FIG. 7, when the second operation wire 42 is pulled, the tubular member 4 is bent in the direction of the arrow X2 in FIG. At this time, the detent portion 112 gradually moves toward the proximal side, that is, toward the wire retaining member 100 as a restraining member. In the middle of the movement stop portion 112 moving toward the wire fastening member 100, the radius of curvature of the tubular member 4 in the curved region M to be formed is substantially uniform, and the shape of the curved portion of the tubular member 4 is predetermined. It can be approximated by a circular arc of radius. Therefore, the curved region M is a curved region M1 having a relatively large curvature radius as a whole. Note that the radius of curvature gradually decreases as the detent portion 112 moves toward the wire retaining member 100. In other words, the radius of the arc that approximates the shape of the curved region M gradually decreases.

Further, when the pulling operation of the second operation wire 42 is advanced, as shown in FIG. 8, the movement stopping portion 112 comes into contact with the wire fastening member 100 as the stopping member, and the movement of the movement stopping portion 112 is stopped. . As a result, the position of the movement stopper 112 is fixed by the wire fastening member 100. In addition, a portion of the second operation wire 42 on the distal side of the movement stop portion 112 is restrained by a region distal to the wire fastening member 100 of the tubular member 4. In this state, when the second operation wire 42 is further pulled, the detent portion 112 functions as an anchor, so that the degree of curvature of the tubular member 4 increases at a portion proximal to the wire fastening member 100. . In other words, the region of the tubular member 4 proximal to the wire fastening member 100 as the restraining member is curved with a smaller radius of curvature than the region of the tubular member 4 distal to the wire fastening member 100. Therefore, in the curved region M, the distal side of the wire fastening member 100 is a curved region M1 having a relatively large radius of curvature, and the proximal side of the wire fastening member 100 is a curved region M2 having a relatively small radius of curvature. That is, the curve shape of the catheter 2 has two stages.

When the distance from the distal end of the catheter 2 to the wire fastening member 100 as the restraining member is 200 mm when the catheter 2 is linear, the distance between the wire fastening member 100 and the detent portion 112 is, for example, 30 mm.

In the catheter 2 according to the second embodiment described above, when the second operation wire 42 is pulled, the detent portion 112 serves as an anchor that fixes the position at a predetermined distance from the distal end of the second operation wire 42. Function. Thereby, the curvature radius of the curved catheter 2 is different between the distal side and the proximal side from the wire fastening member 100 as the restraining member, and the curvature radius of the catheter 2 proximal to the wire fastening member 100 is different from the wire fastening member 100. It becomes smaller than the radius of curvature of the more distal catheter 2. Therefore, the variation of the curve shape of the catheter tip can be further increased, and as a result, the operability of the catheter 2 can be further improved.

The present invention is not limited to the above-described embodiments, and various modifications such as design changes can be added based on the knowledge of those skilled in the art, and the embodiments to which such modifications are added are also possible. It can be included in the scope of the present invention. A new embodiment generated by the combination of the above-described embodiment and the following modified example has the effects of the combined embodiment and modified example.

In the catheter 2 of Embodiment 2 described above, one set of the wire fastening member 100 as the restraining member and the detent portion 112 is provided, but two or more pairs of the restraining member and the detent portion 112 may be provided. In this case, the curve shape of the catheter 2 can be multi-staged according to the number of sets of the provided stationary member and the detent portion 112.

Further, in the catheter 2 of the second embodiment described above, the detent portion 112 is provided on the second operation wire 42, but the detent portion 112 may be provided on the first operation wire 40 side. In this case, for example, a restraining member is provided on the proximal side of the wire fastening member 100, and the movement stopper 112 is provided in a region between the wire fastening member 100 and the restraining member of the first operation wire 40. Alternatively, the detent portions 112 may be provided on both the first operation wire 40 and the second operation wire 42.

2 catheter, 4 tubular member, 21 first lumen, 22 second lumen, 40 first operation wire, 42 second operation wire, 100 wire fastening member, 101, 102, 103, 106 hollow part, 110 locking member , M, N curved area, O straight area, 112 detent.

The present invention can be used for a catheter.

Claims

A flexible tubular member having a plurality of lumens formed along the axial direction;
A first operation wire inserted through the first lumen among the plurality of lumens;
A second operating wire inserted through a second lumen of the plurality of lumens;
With
The tubular member bends in a first direction when the first operation wire is pulled, and curves in a second direction when the second operation wire is pulled.
The first curved region formed when bent in the first direction and the second curved region formed when bent in the second direction are at least partially offset in the axial direction of the tubular member,
A catheter in which a straight region is formed in a predetermined range from the distal end portion of the tubular member when bent in the first direction, and the first curved region is formed on the proximal side of the straight region.
The catheter according to claim 1, wherein the first curved region and the second curved region have different minimum radii of curvature.
The catheter according to claim 1 or 2, wherein the straight region has a length of 3 to 15 mm.
The first manipulation wire has a distal end fixed between a distal end and a proximal end of the tubular member;
The catheter according to any one of claims 1 to 3, wherein a distal end of the second manipulation wire is fixed at a distal end of the tubular member.
From an inner diameter of a lumen provided between a distal end and a proximal end of at least one of the first operating wire and the second operating wire, and through which the at least one operating wire is inserted. A restraining member provided with a hollow portion having a small inner diameter so that the at least one operation wire can be inserted;
A detent portion provided at a predetermined location of the at least one manipulation wire distal to the restraining member, and having an outer diameter larger than an inner diameter of the hollow portion;
With
When the at least one manipulation wire is pulled, a portion of the at least one manipulation wire that is distal to the detent portion is restrained by a region distal to the restraining member of the tubular member. The catheter according to any one of claims 1 to 4.
The curvature radius of the tubular member proximal to the restraining member is smaller than the curvature radius of the tubular member distal to the restraining member when the detent portion is restrained by the restraining member. The catheter described.