JP2013056092A - Catheter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a catheter capable of coaxially engaging a distal end of the catheter with a coronary artery hole and enhancing backup force when the coronary artery hole extends from a position displaced forward or rearward more than usual.SOLUTION: The catheter 10 has the first curvature part 32 having the first curvature radius and the first arc length, the second curvature part 38 curved in the same direction as that of the first curvature part 32 and having the second curvature radius smaller than the first curvature radius 32 and the second arc length shorter than the first arc length, and the third curvature part 40 curved in a direction opposite to the second curvature part 38. The first planar surface formed by a shaft body part 30 and the first curvature part 32 is inclined to the second planar surface formed by a catheter shaft 20 of a distal end side from at least a part of the second curvature part 38, a distance D2 between the first curvature part 32 and the third curvature shaft 40 is smaller than a distance D1 between the distal end and the rear end of the second curvature 38.

Description

  The present invention relates to a catheter used for diagnosis and treatment of the heart and the like.

  Conventionally, various shapes of guiding catheters and contrast catheters used for heart diagnosis and treatment have been developed so as to surely engage with coronary arteries extending from the ascending aorta (for example, Patent Documents 1 to 3 listed below). 5).

  Such a catheter is required to reliably engage the coronary artery hole, which is the entrance of the coronary artery, as described above. In addition, in a catheter such as a guiding catheter into which a therapeutic catheter such as a balloon catheter is inserted, the distal end portion of the guiding catheter is moved into the coronary artery hole while the therapeutic catheter is operated. Therefore, a force for supporting the treatment catheter, that is, a so-called back-up force is required.

JP 2006-230482 A Japanese National Patent Publication No. 10-505530 JP 7-506282 Gazette JP-T-2004-533858 Japanese National Patent Publication No. 11-512302

  However, the state in which the coronary artery extends from the ascending aorta is different for each patient. For example, when the coronary artery hole extends from a position displaced forward (chest side) than normal, or when the coronary artery hole extends from a position displaced backward (back side) from normal, Since the distal end portion is twisted by the amount of displacement, it is difficult to engage the distal end of the catheter coaxially with the coronary artery hole and obtain a sufficient backup force. In addition, since a force to restore the twist caused by the displacement acts, the tip of the catheter tends to be easily detached from the coronary artery hole.

  The present invention has been made in view of such circumstances, and when the coronary artery hole extends from a position displaced forward or backward than usual, the distal end of the catheter is coaxially formed in the coronary artery hole. It is an object of the present invention to provide a catheter that can be engaged and increase the backup force.

<1> A catheter comprising a tubular catheter shaft having a lumen therein, wherein the catheter shaft is formed in a natural state in a substantially straight shaft main body portion and a distal end side of the shaft main body portion, and has a first curvature. A first bending portion having a radius and a first arc length, and a second curvature radius formed on a distal end side of the first bending portion, curved in the same direction as the first bending portion, and smaller than the first curvature radius And a second bending portion having a second arc length shorter than the first arc length, and a third bending portion that is formed on the distal end side of the second bending portion and curves in a direction opposite to the second bending portion. A first plane formed by the shaft main body portion and the first curved portion is inclined with respect to a second plane formed by the catheter shaft on the distal end side from at least a part of the second curved portion, The first bending portion and the 3 shortest linear distance between the curved portion, the catheter, wherein the second or less straight line distance between the tip and the rear end of the bending portion.

<2> The catheter according to aspect 1, comprising a linear first straight part formed between the first curved part and the second curved part.

<3> Aspect 1 or 2, wherein the first curved portion is formed on the distal end side of the third curved portion, has a linear second straight portion, and the second straight portion and the first curved portion are substantially parallel. 2. The catheter according to 2.

<4> The catheter according to any one of aspects 1 to 3, wherein an angle at which the first plane is inclined with respect to the second plane is about 10 ° to about 15 °.

<1> In the catheter of the present invention, when the distal end portion is inserted toward the left coronary artery hole, the second plane formed by the catheter shaft on the distal end side from at least a part of the second curved portion is the shaft main body portion and It inclines with respect to the 1st plane which a 1st curved part forms. Further, the shortest straight distance between the first bending portion and the third bending portion is equal to or less than the linear distance between the front end and the rear end of the second bending portion. With this configuration, even when the left coronary artery hole is displaced forward or backward than usual, the distal end portion of the catheter can be smoothly inserted into the left coronary artery and opposite to the left coronary artery hole of the ascending aorta At least a part of the first curved portion comes into linear contact with the inner wall surface on the side, and the backup force can be kept high.

At this time, since the third bending portion is bent in the opposite direction to the first bending portion and the second bending portion, even if the distal end portion of the catheter contacts the upper wall surface of the left coronary artery hole, Since the arc portion comes into contact, the distal end portion of the catheter can be safely engaged with the left coronary artery hole.
In addition, the distal end portion of the third bending portion can be inserted coaxially with the left coronary artery hole.

  That is, even if a force acts in a direction to remove the distal end portion of the catheter from the left coronary artery hole after the catheter is placed, the distal end portion of the catheter is inserted coaxially into the left coronary artery hole, and the first curved portion At least a part of which contacts linearly with the inner wall surface of the ascending aorta opposite to the left coronary artery hole. For this reason, it can prevent that the front-end | tip part of a catheter slips out of a left coronary artery hole with high backup force.

  In addition, since the second plane formed by the distal catheter shaft from at least a part of the second curved portion is inclined with respect to the first plane formed by the shaft main body portion and the first curved portion, the left coronary artery Even when the hole is displaced forward or backward, this displacement prevents the catheter from being twisted. For this reason, it can further prevent that the front-end | tip part of a catheter slips out of a left coronary artery hole during a procedure.

<2> In aspect 2 of the present invention, the catheter has a linear first straight portion between the first curved portion and the second curved portion. By providing the first straight portion, the backup force can be kept high when the catheter is engaged with the left coronary artery hole. That is, since the first straight portion is more linearly contacted with the inner wall surface of the ascending aorta opposite to the left coronary artery hole, the distal end of the catheter engaged with the left coronary artery hole extends from the left coronary artery hole. Further detachment can be prevented.

<3> In aspect 3 of the present invention, the catheter has a linear second straight portion formed on the distal end side of the third curved portion, and the second straight portion and the first curved portion are substantially parallel to each other. Yes. By arranging in this way, the end surface of the distal end of the second straight portion, which is the distal end of the catheter, is prevented from contacting the inner wall of the blood vessel below the left coronary artery hole, and the inner wall of the blood vessel is prevented from being pushed downward. And safety is improved.

  Further, not only when the left coronary artery hole is displaced forward or backward, but also when the left coronary artery hole is displaced downward, the second straight portion which is the distal end portion of the catheter can be easily inserted into the left coronary artery hole. Furthermore, even when the left coronary artery hole is displaced downward, the first curved portion can sufficiently contact the inner wall surface of the ascending aorta opposite to the left coronary artery hole, and a high backup force can be exhibited. it can.

<4> In the aspect 4 of the present invention, the angle at which the first plane is inclined with respect to the second plane is set to about 10 ° to about 15 °. Thereby, even when the left coronary artery hole is displaced forward or backward than usual, the distal end portion of the catheter can be smoothly and accurately inserted into the left coronary artery hole.
In addition, even when the distal end of the catheter acts in the direction of exiting from the left coronary artery hole during the procedure, the catheter is twisted because the shape is formed in consideration of the displacement angle of the left coronary artery hole in advance. It is prevented that a force to return is generated. For this reason, it can further prevent that the front-end | tip part of a catheter slips out of a left coronary artery hole during a procedure.

FIG. 1 is an overall view of the catheter of the present embodiment. FIG. 2 is a diagram for explaining the configuration of the catheter of the present embodiment. FIG. 3 is a view of FIG. 1 viewed from the direction of arrow III. FIG. 4 is a cross-sectional view of the distal end portion of the catheter of the present embodiment. FIG. 5 is a diagram for explaining the operation of the catheter of the present embodiment. FIG. 6 is a diagram for explaining the operation of the catheter of the present embodiment. FIG. 7 is a view showing a second embodiment of the catheter.

The catheter of the present embodiment will be described with reference to FIGS.
1, 2, and 4, the left side in the drawing toward the chip 50 is the distal end side (distal side) inserted into the body, and the right side is the rear end side (proximal side, proximal end) operated by an operator such as a doctor. Side).
In the case of the present embodiment, the total length of the catheter 10 is set in the range of about 900 mm to about 1500 mm, and is about 1100 mm.

1 and 2 are plan views of the catheter 10, and FIG. 3 is a view seen from the direction of arrow III in FIG. FIG. 4 is a cross-sectional view of the distal end portion of the catheter 10.
In FIG. 4, for easy understanding, a third bending portion 40 provided at the distal end of the catheter 10 to be described later is shown in a state of being straightened. For ease of understanding, the dimensions of some components are exaggerated.

  The catheter 10 is a diagnostic catheter. In the case of the present embodiment, the catheter 10 is a guiding catheter for guiding a balloon catheter or the like for treating a stenosis of a heart blood vessel or the like. The catheter 10 is for the left coronary artery.

  The catheter 10 mainly includes a catheter shaft 20 and a connector 60.

  The catheter shaft 20 is a tubular member having a lumen 22 inside and a circular cross section. In the case of the present embodiment, the outer diameter of the catheter shaft 20 is set in a range of about 2.0 mm to about 3.0 mm, and is about 2.1 mm. In the present embodiment, the inner diameter of the catheter shaft 20 is set to a range of about 1.75 mm to about 2.75 mm, and is about 1.78 mm.

  The catheter shaft 20 has a tip 50 to be described later at the tip. The portions other than the tip 50 of the catheter shaft 20 are made of resin, an inner layer 23 constituting the lumen 22, a braid 24 arranged on the outer surface of the inner layer 23, and an outer layer made of resin covering the outer surface of the braid 24. 25. The outer layer 25 is made of a resin that is more flexible toward the distal end so that the catheter shaft 20 becomes more flexible toward the distal end.

As the resin constituting the inner layer 23 and the outer layer 25 of the catheter shaft 20, for example, polyamide, polyester, polyurethane, or the like is used. The braid 24 has a known configuration in which a metal wire such as stainless steel or tungsten is wound in a mesh shape.
The braid 24 may have a coiled configuration in which a single wire is wound. Further, the braid 24 is not an essential configuration and can be omitted.

  The catheter shaft 20 of the present embodiment is roughly divided into three curved portions. That is, the catheter shaft 20 includes a shaft main body 30, a first bending portion 32, a first straight portion 35, a second bending portion 38, a third bending portion 40, and a second straight portion 43 in this order from the hand side. .

  The shaft main body 30 is a portion other than the first bending portion 32, the first straight portion 35, the second bending portion 38, the third bending portion 40, and the second straight portion 43, which is the distal end portion of the catheter 10. The shaft main body 30 is a substantially linear portion in a natural state where the catheter 10 is outside the body.

  The first bending portion 32 is the bending portion located on the most rear end side, and is the bending portion having the longest arc and the largest curvature radius. In the present embodiment, the first radius of curvature R1, which is the radius of curvature of the first curved portion 32, is set to a range of about 105 mm to about 125 mm, and is about 115 mm. In the present embodiment, the angle θ1 at which the first bending portion 32 bends (the central angle of the arc formed by the first bending portion 32) is set in the range of about 40 ° to about 60 °, more preferably. , About 45 ° to 55 °, specifically about 50 °. In the present embodiment, the first arc length Lc1, which is the arc length of the first bending portion 32, is about 100 mm.

  In the case of the present embodiment, the first bending portion 32 is composed of one bending portion formed from one first curvature radius R1, but a second bending portion 38 and a third bending portion to be described later. Like 40, you may comprise from a several different curved part.

  The first straight part 35 is a linear part located on the distal end side of the first bending part 32. In the present embodiment, the length Ls1 of the first straight portion 35 is about 20 mm or less, and is preferably set in the range of about 10 mm to about 20 mm. Specifically, it is about 15 mm.

  By providing the straight first straight portion 35, as shown in FIG. 6, when the catheter 10 is engaged with the left coronary artery hole 81a, the backup force can be kept high. That is, the first straight portion 35 linearly contacts the inner wall surface 80a of the ascending aorta 80 opposite to the left coronary artery hole 81a, so that the tip of the cattail 10 engaged with the left coronary artery hole 81a is left coronal. It can prevent coming off from the artery hole 81a.

  The first straight portion 35 is not always necessary, and may be omitted when the first bending portion 32 is elongated and connected to the second bending portion 38 described later. In this case, the first curved portion 32 having a large radius of curvature linearly contacts the inner wall surface 80a of the ascending aorta 80 on the side opposite to the left coronary artery hole 81a, and the distal end of the catheter 10 comes off the left coronary artery hole 81a. Will be prevented.

  The second bending portion 38 is a bending portion located on the distal end side of the first straight portion 35 and is bent in the same direction as the first bending portion 32. The second arc length Lc2 that is the arc length of the second bending portion 38 is shorter than the first arc length Lc1 of the first bending portion 32, and the second curvature radius R2 that is the curvature radius of the second bending portion 38. Is shorter than the first curvature radius R1 of the first bending portion 32. More specifically, the second arc length Lc2 of the second bending portion 38 is shorter than the first arc length Lc1 of the first bending portion 32 by about 25 mm or more. Further, the second curvature radius R2 of the second curved portion 38 is also shorter than the first curvature radius R1 of the first curved portion 32 by about 90 mm or more.

The second arc length Lc2 of the second bending portion 38 is longer than the third arc length Lc3, which is the arc length of the third bending portion 40 described later, and the second curvature radius R2 of the second bending portion 38. Is shorter than the third radius of curvature R3, which is the radius of curvature of the third curved portion 40.
In the case of the present embodiment, the second radius of curvature R2 of the second curved portion 38 is set in the range of about 9.0 mm to about 13.0 mm. Further, the second bending portion 38 has an angle θ2 at which the second bending portion 38 bends (the second bending portion 38 has the second bending portion 38 in order to bend the catheter shaft 20 in the direction toward the first bending portion 32 or the first linear portion 35. The central angle of the circular arc formed is larger than 180 ° and curved to about 200 ° or less. In the case of the present embodiment, the second bending portion 38 is bent approximately 190 ° as a whole.

The second bending portion 38 includes a rear end side second bending portion 38a and a front end side second bending portion 38b that are bent in the same direction.
The rear end side second bending portion 38a has a rear end side second arc length Lc2a which is the length of the arc, in the present embodiment, approximately 21 mm. In the case of the present embodiment, the rear end side second curvature radius R2a, which is the curvature radius of the rear end side second curved portion 38a, is about 9.5 mm. Of the angle θ2 (about 190 °) at which the second bending portion 38 bends, the angle θ2a at which the rear end side second bending portion 38a bends is about 125 °.

In the distal end side second bending portion 38b, the distal end side second arc length Lc2b, which is the length of the arc, is about 14 mm in the present embodiment. In the present embodiment, the distal-side second curvature radius R2b, which is the curvature radius of the distal-side second curved portion 38b, is approximately 12.5 mm. Of the angle θ2 (about 190 °) at which the second bending portion 38 bends, the angle θ2b at which the distal end side second bending portion 38b bends is about 65 °.
As shown in FIG. 2, the rear end side second curvature radius R2a of the rear end side second curved portion 38a and the distal end side second curvature radius R2b of the distal end side second curved portion 38b are different, so that the center point is Although different, here, the angle θ2a at which the rear end side second bending portion 38a is bent and the angle θ2b at which the front end side second bending portion 38b are bent are simply added to obtain the angle θ2 at which the second bending portion 38 is bent as a whole. About 190 °.

  Moreover, the 2nd bending part 38 can also be comprised from one bending part, without dividing into the rear end side 2nd bending part 38a and the front end side 2nd bending part 38b. Furthermore, although it can also comprise from the combination of 3 or more curved parts, even in this case, each curved part needs to bend in the same direction.

  The third bending portion 40 is a bending portion located on the distal end side of the second bending portion 38 and is bent in the direction opposite to the first bending portion 32 and the second bending portion 38. The third arc length Lc3 that is the arc length of the third bending portion 40 is shorter than the second arc length Lc2 of the second bending portion 28. On the other hand, the third radius of curvature R3, which is the radius of curvature of the third curved portion 40, is longer than the second radius of curvature R2 of the second curved portion 38. In the case of the present embodiment, the third radius of curvature R3 of the third curved portion 40 is set in the range of about 10.0 mm to about 65.0 mm. The angle θ3 at which the third bending portion 40 is bent (the central angle of the arc formed by the third bending portion 40) is set in a range of about 25 ° to about 40 °. In the case of the present embodiment, the catheter shaft 20 is bent by about 36 ° as a whole in the third bending portion 40. Further, the third arc length Lc3 of the third bending portion 40 is about 16 mm.

The 3rd bending part 40 is comprised from the rear end side 3rd bending part 40a and the front end side 3rd bending part 40b which curve in the same direction.
In the present embodiment, the rear end side third curvature radius R3a, which is the curvature radius of the rear end side third curved portion 40a, is set in a range of about 55.0 mm to about 65.0 mm, and is about 60 mm. Has been. In the present embodiment, the angle θ3a at which the rear end side third bending portion 40a bends is set in the range of about 5.0 ° to about 10 °. Specifically, the angle θ3a is about 8.0 ° out of the angle θ3 (about 36 °) at which the third bending portion 40 bends. In this embodiment, the rear end side third arc length Lc3a, which is the length of the arc of the rear end side third bending portion 40a, is about 8.5 mm.

  In the present embodiment, the distal-side third curvature radius R3b, which is the curvature radius of the distal-side third curved portion 40b, is set in the range of about 10.0 mm to about 20.0 mm, and is about 15 mm. Yes. In the present embodiment, the angle θ3b at which the distal end side third bending portion 40b bends is set in the range of about 25.0 ° to about 30 °. Specifically, the angle θ3b is about 28 ° out of the angle θ3 (about 36 °) at which the third bending portion 40 bends. In the present embodiment, the tip side third arc length Lc3b, which is the length of the arc of the tip side third bending portion 40b, is about 7.4 mm.

By providing the third bending portion 40 that bends in the opposite direction to the first bending portion 32 and the second bending portion 38, the distal end of the catheter 10 can be safely and coaxially engaged with the left coronary artery hole 81a. That is, when the distal end of a general catheter engages with the left coronary artery hole 81a, the distal end portion of the catheter extends in the direction from below to above, and the end surface of the distal end of the catheter is above the left coronary artery hole 81a. It will contact the wall surface. However, as shown in FIG. 6, the catheter 10 of the present embodiment has a circular arc portion of the third bending portion 40 on the upper wall surface of the left coronary artery hole 81a when the distal end engages with the left coronary artery hole 81a. Because of the contact, damage to the blood vessel wall can be prevented.
In addition, the second linear portion 43 on the distal end side from the arc portion of the third bending portion 40 can be inserted coaxially with the left coronary artery hole 81a.

  As shown in FIG. 2, since the rear end side third curvature radius R3a of the rear end side third curved portion 40a and the distal end side third curvature radius R3b of the distal end side third curved portion 40b are different, the center point thereof is Here, the angle θ3a at which the rear end side third bending portion 40a is bent and the angle θ3b at which the front end side third bending portion 40b are bent are simply added to obtain the angle θ2 at which the third bending portion 40 is bent as a whole. About 36 °.

Moreover, the 3rd bending part 40 can also be comprised from one bending part, without dividing into the rear end side 3rd bending part 40a and the front end side 3rd bending part 40b. In this case, it is also possible to configure the rear end side third bending portion 40a from a linear portion.
Furthermore, although the 3rd bending part 40 can also be comprised from the combination of 3 or more bending parts, even in this case, each bending part needs to bend in the same direction.

  The second linear portion 43 is a linear portion located on the distal end side of the third bending portion 40. A tip portion of the second linear portion 43 is a chip 50. In the case of the present embodiment, the length Ls2 of the second straight line portion 43 is set to about 5.0 mm or less, and more preferably is set to a range of about 3.0 mm to about 5.0 mm. Specifically, it is about 4.0 mm. Among these, the tip of about 2.0 mm is the chip 50.

  As shown in FIG. 4, the chip 50 is a cylindrical member having a hole that constitutes the distal end portion of the lumen 22, and is made of a single resin. The tip 50 has a tip opening 22a at which the lumen 22 opens at the tip. The length of the tip 50 in the axial direction is set to about 2.0 mm to about 3.0 mm, and is about 2.0 mm as described above.

  The resin used for the tip 50 is composed of the same resin as that constituting the inner layer 23 and the outer layer 25 of the catheter shaft 20, but usually a softer resin than the resin constituting the catheter shaft 20 is used. Yes. The resin constituting the chip 50 contains a powder made of a radiopaque material in order to confirm the position of the catheter 10 under radioscopy.

A tip portion of the chip 50 is provided with a tapered portion 50a that tapers toward the tip.
The second linear portion 43 is not necessarily required and may be omitted. In this case, the tip 50 needs to be provided at the tip of the third bending portion 40.

  As shown in FIG. 3, the second bending portion 38, the third bending portion 40, and the second straight portion 43, which are located on the tip side with respect to the first straight portion 35, When the part 35 is omitted, it is biased in an oblique direction with respect to the axis of the first bending part 32). That is, the second plane S2 formed by the second bending portion 38, the third bending portion 40, and the second linear portion 43 is the first plane formed by the shaft main body portion 30, the first bending portion 32, and the first linear portion 35. It is inclined with respect to one plane S1. The second plane S2 formed by the second bending section 38, the third bending section 40, and the second straight section 43 is the first plane formed by the shaft main body section 30, the first bending section 32, and the first straight section 35. In the present embodiment, the angle α inclined with respect to S1 is set in a range of about 10 ° to about 15 °, and α = 10 °.

  FIG. 3 shows the third bending portion when the second bending portion 38 is on the upper side and the third bending portion 40 and the second straight portion 43 are viewed forward of the first bending portion 32 and the first straight portion 35. 40 shows a configuration in which 40 and the second linear portion 43 face the lower left side of the first curved portion 32 and the first linear portion 35. This configuration is suitable for the case where the left coronary artery extends from a position 81a displaced rearward (back side) from the normal position 81 in FIG. Show. Conversely, when the left coronary artery extends from a position 81b displaced forward (chest) from the normal position 81, the form shown in FIG. 7 is obtained. That is, when the second bending portion 38 is on the upper side, and the third bending portion 40 and the second straight portion 43 are viewed on the front side from the first bending portion 32 and the first straight portion 35, it is opposite to FIG. 3. The third bending portion 40 and the second straight portion 43 are configured to face the lower right side of the first bending portion 32 and the first straight portion 35.

  As described above, the second plane S2 formed by the second bending portion 38, the third bending portion 40, and the second straight portion 43 is the shaft main body 30, the first bending portion 32, and the first straight portion 35. When the angle α inclined with respect to the first plane S1 to be formed is 10 °, the distance h between the left and right ends of the catheter shaft 20 shown in FIG. 3 is about 7.0 mm.

  The linear distance D1 connecting the inner sides of the curved catheter shaft 20 from the rear end X1 to the tip X2 of the second bending portion 38 shown in FIG. 1 is about 18 mm. Further, the first bending portion 32 from the point Y2 at which the third bending portion 40 is closest to the first bending portion 32 in the shortest distance D2 between the third bending portion 40 and the first bending portion 32, that is, inside the catheter shaft 20. The linear distance from the point Y1 is about 13.5 mm. Thus, in the catheter 10 of the present embodiment, the distance D2 is set to be equal to or less than the distance D1, and preferably, the distance D2 is set to be smaller than the distance D1.

  As described above, the distance D2 is set to be equal to or less than the distance D1, and the second plane S2 described above is inclined at an angle α with respect to the first plane S1, so that the left coronary artery hole is posterior to the normal position 81. Even in the case of the position 81a displaced to (or the anterior side), it can be easily inserted into the left coronary artery hole 81a. In addition, due to this shape, even when the second straight portion 43 is inserted into the displaced left coronary artery hole 81a, the first straight portion 35 is formed on the inner wall surface 80a of the ascending aorta 80 opposite to the left coronary artery hole 81a. The contact force is linear, and the backup force can be kept high.

The distal end catheter shaft 20 after the third bending portion 40 is closest to the first bending portion 32 is in a state of being substantially parallel to the first bending portion 32. That is, as shown by the line segment P1 drawn to the first curved part 32 side in FIG. 1 and the line segment P2 obtained by extending the second straight line part 43, the second straight line part 43 and the first curved part 32 are substantially the same. It becomes a parallel state.
Accordingly, the catheter shaft 20 is bent by the second bending portion 38 to be larger than 180 ° and separated by the linear distance D1, and then approaches the first bending portion 32. Thereafter, the space between the third bending portion 40 and the first bending portion 32 becomes narrower and the shortest linear distance D2 is obtained. Furthermore, after that, the 1st curved part 32 and the 2nd linear part 43 will be in a substantially parallel state.

  The reason why the first bending portion 32 and the second straight portion 43 are arranged in a substantially parallel state is as follows. That is, when the first curved portion 32 and the second straight portion 43 are greatly opened outward from the parallel state, the end surface of the tip 50 at the distal end of the catheter 10 contacts the blood vessel inner wall below the left coronary artery hole 81a. In addition, there is a high possibility that a force that pushes the inner wall of the blood vessel downward acts, and safety is reduced.

  Conversely, if the first curved portion 32 and the second straight portion 43 are narrower inward than the parallel state, not only when the left coronary artery hole 81a is displaced backward (or forward), but also downward This is because it may be difficult to insert the distal end of the catheter 10 into the left coronary artery hole 81a. In such a case, an operation may be performed in which the catheter 10 is pulled toward the hand side so that the distal end of the catheter 10 is directed downward, and the distal end of the cattail 10 directed downward is pushed into the left coronary artery hole 81a. In this case, the first straight portion 35 (or the first curved portion 32) may not sufficiently come into contact with the inner wall surface 80a of the ascending aorta 80 opposite to the left coronary artery hole 81a. There is a possibility of deteriorating the backup power. Therefore, by maintaining the first curved portion 32 and the second straight portion 43 in a substantially parallel state, the second straight portion 43 can be easily moved to the left coronary artery hole 81a even when the left coronary artery hole 81a is displaced downward. In addition, the insertion can be surely performed, and the first straight portion 35 (or the first curved portion 32) can be sufficiently brought into linear contact with the inner wall surface 80a of the ascending aorta 80 to exhibit a high backup force.

  The distal end of the catheter 10 approaches and engages from below the left coronary artery hole 81a and engages. Therefore, when the left coronary artery hole 81a is displaced upward, the entire catheter 10 is moved above the normal position. Since operation is sufficient, it can be handled relatively easily.

  The connector 60 is attached to the rear end of the catheter shaft 20. The connector 60 has a hole communicating with the lumen 22 of the catheter shaft 20 inside. A rear end opening 60 a for inserting a guide wire, a balloon catheter or the like into the lumen 22 is provided at the rear end of the connector 60.

  Based on the above configuration, referring to FIG. 6, the catheter 10 according to the present embodiment is used as a guiding catheter to treat a stenosis that is a target site of treatment formed inside the left coronary artery 80. The case of using will be described. The left coronary artery hole 81 a of the present embodiment is an opening where the left coronary artery 82 opens toward the ascending aorta 80. Further, the left coronary artery hole 81a is located at a position displaced rearward (back side) from the left coronary artery hole 81 at the average position. In addition, the figure number 85 is a right coronary artery hole.

  The example shown in FIG. 6 shows a case where the catheter 10 is inserted from the femoral artery. Before the catheter 10 is inserted, the guide wire 70 passes through the descending aorta 83, the aortic arch 84, and the ascending aorta 80 and is inserted into the left coronary artery hole 81a.

  The rear end of the guide wire 70 is inserted from the distal end opening 22 a provided in the tip 50 of the catheter 10. Then, an operator such as a doctor advances the catheter 10 along the guide wire 70 via the descending aorta 83, the aortic arch 84, and the ascending aorta 80, and the second straight portion 43 enters the left coronary artery hole 81a. Insert it toward you.

  The second plane S2 formed by the second bending portion 38, the third bending portion 40, and the second linear portion 43 of the catheter 10 is formed by the shaft main body portion 30, the first bending portion 32, and the first linear portion 35. It is inclined at an angle α with respect to the first plane S1. Further, the linear distance D1 connecting the rear end X1 to the front end X2 of the second bending portion 38 is set to be larger than the shortest distance D2 between the third bending portion 40 and the first bending portion 32. For this reason, although the left coronary artery hole 81a is displaced rearward, the second straight portion 43 is smoothly inserted into the left coronary artery hole 81a along the guide wire 70.

Here, since the third curved portion 40 behind the second linear portion 43 is curved in the opposite direction to the first curved portion 32 and the second curved portion 38, the catheter 10 is placed on the upper wall surface of the left coronary artery hole 81a. Even if the distal end portion comes into contact, as shown in FIG. 6, since the arc portion of the third bending portion 40 comes into contact, the distal end of the catheter 10 can be safely engaged with the left coronary artery hole 81a.
Further, the second straight line portion 43 on the distal end side with respect to the third bending portion 40 can be inserted coaxially with the left coronary artery hole 81a.

  In a state where the second straight portion 43 is inserted coaxially with the left coronary artery hole 81a, the first straight portion 35 and a part of the first curved portion 32 are on the opposite side of the left coronary artery hole 81a of the ascending aorta 80. It contacts linearly with the inner wall surface 80a. Thereby, the placement of the catheter 10 is completed.

  In the above process, even if the left coronary artery hole 81a is displaced downward than usual, the first curved portion 32 and the second straight portion 43 are shaped in a substantially parallel state, so that And the 2nd straight part 43 can be safely inserted in the left coronary artery hole 81a. Further, a part of the first straight portion 35 and the first curved portion 32 can be brought into linear contact with the inner wall surface 80a of the ascending aorta 80 on the opposite side to the left coronary artery hole 81a.

  When the catheter 10 is arranged in this manner, the guide wire 70 is removed through the rear end opening 60 a of the connector 60. Then, another guide wire 71 for treatment is inserted into the stenosis of the left coronary artery 82 through the lumen 22 of the catheter 10 from the rear end opening 60 a of the connector 60. Similarly, a treatment catheter such as a balloon catheter is inserted into the catheter 10 along the guide wire 71 and inserted toward the stenosis of the left coronary artery 82. When a treatment catheter such as a balloon catheter approaches the stenosis portion along the guide wire 71, the treatment catheter passes through the bending blood vessel, so that the treatment catheter bends and bends. The force generated by this bending or the like acts in a direction to remove the distal end of the catheter 10 that is a guiding catheter from the left coronary artery hole 81a. However, the catheter 10 is coaxially inserted into the left coronary artery hole 81a, and the inner wall surface 80a of the ascending aorta 80 on the side opposite to the left coronary artery hole 81a is part of the first straight portion 35 and the first curved portion 32. Is in linear contact. For this reason, the catheter 10 exhibits a high backup force, and can prevent the second straight portion 43 from coming off the left coronary artery hole 81a.

  Further, the second plane S2 formed by the second bending portion 38, the third bending portion 40, and the second straight portion 43 is formed by the shaft main body 30, the first bending portion 32, and the first straight portion 35. Since the left coronary artery hole 81a is displaced backward with respect to the one plane S1, the catheter 10 is prevented from being twisted due to this displacement. For this reason, it can further prevent that the 2nd straight part 43 slips out from the left coronary artery hole 81a.

  In such a state, after treatment of the stenosis in the left coronary artery 82 is performed by a therapeutic catheter such as a balloon catheter, the therapeutic guide wire 71 and the therapeutic balloon catheter or the like connect the catheter 10. Is removed from the body. Thereafter, the catheter 10 is removed from the body, and the procedure is completed.

  Note that the timing for replacing the guide wire 70 and the guide wire 71 and the method of use differ depending on the operator, and are not limited to the above procedure.

  In the embodiment described above, the third arc length Lc3 of the third bending portion 40 is shorter than the second arc length Lc2 of the second bending portion 28. The third curvature radius R3 of the third bending portion 40 is larger than the second curvature radius R2 of the second bending portion 38. Such a shape is preferable in forming a shape that keeps the first curved portion 32 and the second straight portion 43 substantially parallel as described above. However, the shape of the third bending portion 40 is not limited to such a shape, and the third bending portion 40 is bent in the opposite direction to the first bending portion 32 and the second bending portion 38, and If the linear distance D1 connecting the inner sides from the rear end to the front end of the bending portion 38 is equal to or longer than the shortest distance D2 between the third bending portion 40 and the first bending portion 32, the certain effect of the present invention can be obtained. it can.

  In the above-described embodiment, the case where the catheter 10 is a guiding catheter has been described. However, the embodiment can be applied to other catheters such as a contrast catheter.

DESCRIPTION OF SYMBOLS 10 Catheter 20 Catheter shaft 22 Lumen 30 Shaft main-body part 32 1st curved part 35 1st linear part 38 2nd curved part 40 3rd curved part 43 2nd linear part S1 1st plane S2 2nd plane R1 1st curvature radius R2a Rear end side second radius of curvature R2b Front end side second radius of curvature Lc1 First arc length Lc2a Rear end side second arc length Lc2b Tip end side second arc length

Claims (4)

A catheter comprising a tubular catheter shaft having a lumen therein, the catheter shaft comprising:
A substantially straight shaft body in a natural state;
A first curved portion formed on the distal end side of the shaft body portion and having a first radius of curvature and a first arc length;
A second curvature radius that is formed on a distal end side of the first bending portion, curves in the same direction as the first bending portion, is smaller than the first curvature radius, and is shorter than the first arc length. A second curved portion having
A third bending portion that is formed on a distal end side of the second bending portion and curves in a direction opposite to the second bending portion;
The first plane formed by the shaft main body and the first bending section is inclined with respect to the second plane formed by the catheter shaft on the distal end side from at least a part of the second bending section,
The shortest linear distance between the first bending portion and the third bending portion is equal to or less than the linear distance between the front end and the rear end of the second bending portion. The catheter according to claim 1, further comprising a linear first straight portion formed between the first curved portion and the second curved portion. 3. The first curved portion according to claim 1 or 2, wherein the second curved portion is formed on a distal end side of the third curved portion, has a linear second straight portion, and the second straight portion and the first curved portion are substantially parallel. The catheter described. The catheter according to any one of claims 1 to 3, wherein an angle at which the first plane is inclined with respect to the second plane is about 10 ° to about 15 °.

Images