WO2018008272A1 - Catheter - Google Patents

Abstract

A catheter 1 is provided with a shaft 5 through which a first wire 7 and a second wire 9 which has a bend at the front end 9a thereof are passed. The shaft 5 has: a first lumen 20 which is formed by a first wall surface 24a and through which the first wire 7 is passed; and a second lumen 22 which is formed by a second wall surface 26a, is provided next to the first lumen 20 with a partition wall therebetween, and has the second wire 9 passed therethrough. The first lumen 20 and the second lumen 22 are arranged in the longitudinal direction of the shaft 5. In a cross-section of the shaft 5, taken perpendicular to the longitudinal direction thereof, a first point P6 on the second wall surface 26a, at which the distance between the outer surface 28a of the shaft 5 and the second wall surface 26a is smallest is located at a position not overlapping with a first straight line D1, D2 which connects predetermined two points P1 and P2 or two points P3 and P4 on the second wall surface 26a and which is longest.

Description

catheter

The present invention relates to a catheter having two lumens through which a wire passes.

An endovascular treatment using a catheter is one of the options for treating a stenosis of a blood vessel. As such an intravascular treatment, there is a surgical method in which a wire is passed through a stenosis of a blood vessel and blood flow is resumed. In such a treatment, a catheter for penetrating a stenosis is used. A typical catheter used for such treatment has two lumens and is used through one wire for each lumen. The wire is used to penetrate the stenosis or guide the catheter to the stenosis. Such a wire is called a guide wire. The tip of the wire used for penetration is often bent to search for the entrance to the stenosis. The surgeon searches the entrance of the stenosis by manipulating the wire, such as by rotating the wire from the proximal side of the catheter. In many cases, the bent portion of the wire is appropriately formed by an operator corresponding to the lesioned portion before use.

As a conventional catheter, for example, the one described in Patent Document 1 is known. The catheter described in Patent Document 1 is used with two lumens which are partitioned by a common wall and have a distal end opening, and a wire is inserted into each lumen. In the catheter described in Patent Document 1, a wire having a bent tip is inserted into one lumen.

There is a catheter described in Patent Document 2 as another catheter of the same type. The catheter described in Patent Document 2 has two lumens (lumens) each having a distal end opening, and is used with a wire inserted into each lumen. In the catheter described in Patent Document 2, each wire is formed so that it does not rotate around the axis at the distal end opening, and the distal ends of the wires are separated from each other along the protruding direction.

JP 2008-295825 A International Publication No. 2012/172858

When a wire having a bent end along with the penetrating catheter is used, the bent portion of the wire having a bent portion at the tip is easily caught on the wall surface of the lumen when moving in the lumen of the catheter. Therefore, in the conventional catheter, the tip of the wire may break through the wall of the lumen. The wire that has broken through the wall may contact the blood vessel and damage the blood vessel.

An object of one aspect of the present invention is to provide a catheter capable of suppressing lumen damage.

The catheter which concerns on 1 side of this invention is equipped with the shaft which passes each of the 1st wire and the 2nd wire which has a bending part in the front-end | tip, and a shaft is formed with the 1st wall surface and lets a 1st wire pass. A first lumen and a second lumen formed by a second wall surface and provided side by side with the first lumen and the partition wall, and allowing the second wire to pass therethrough, the first lumen and the second lumen are: The first point on the second wall surface where the distance between the outer surface of the shaft and the second wall surface is the thinnest in the cross section disposed along the longitudinal direction of the shaft and orthogonal to the longitudinal direction of the shaft is on the second wall surface. It is in a position that connects two predetermined points and does not overlap the longest first straight line.

In the catheter according to one aspect of the present invention, the thinnest portion of the second lumen is disposed at a position that does not overlap the extended line of the first straight line. Thereby, it can avoid that the bending part of a 2nd wire contacts the thinnest part of the distance of a 2nd wall surface and the outer surface of a shaft in a 2nd lumen, and the front-end | tip of a 2nd wire is a 2nd lumen. Can be prevented from sticking into the wall surface, penetrating or breaking through the wall portion and coming into contact with the blood vessel.

In a different embodiment of the present invention, the first lumen is arranged at a position that does not overlap the extension of the first straight line in the cross section, and the second point on the second wall surface where the first point and the partition wall are the thinnest. The second straight line connecting the points is preferably shorter than the first straight line in the cross section. In this configuration, the first straight line does not overlap the outer surface of the shaft of the second lumen and the thinnest part of the partition wall. Thereby, it can prevent that the bending part of a 2nd wire contacts the thinnest part of a partition in a 2nd lumen, and the front-end | tip of a 2nd wire pierces the wall surface of a 2nd lumen, or a wall part Can be prevented from penetrating or breaking the tube and coming into contact with the blood vessel or entering the first lumen.

In one embodiment, the thinnest thickness of the partition wall is smaller than at least one of the thinnest thickness between the first wall surface and the outer surface and the thinnest thickness between the second wall surface and the outer surface. Also good. In this configuration, since the thickness of the outer shell of the shaft is ensured, the outer shell of the shaft can be further prevented from being damaged even when the wire contacts the wall surface of the lumen.

In one embodiment, the material forming the first wall surface and the second wall surface may be more slippery than the material forming the outer shell of the shaft. In this configuration, the first wire and the second wire can be smoothly moved in the first lumen and the second lumen.

In one embodiment, the material forming the outer shell of the shaft preferably has a lower elastic modulus than the material forming the first wall surface and the second wall surface. With this configuration, the flexibility of the shaft can be ensured. A catheter with a flexible shaft is easy to insert into a blood vessel and has high operability.

In one embodiment, a reinforcing layer having a higher strength than the material forming the outer shell of the shaft may be provided in a part including the thinnest portion between the second wall surface and the outer surface. In this configuration, even when the second wire is in contact with the thinnest portion of the second lumen, the reinforcing layer can suppress the second wire from penetrating through the thinnest portion and protruding out of the shaft. .

In one embodiment, the reinforcing layer may be provided around the second lumen. In this configuration, the reinforcing layer can further suppress the second wire from penetrating the wall surface of the second lumen and protruding out of the shaft.

In one embodiment, a first opening is provided at one end of the first lumen on the distal side, a second opening is provided on the other end on the proximal side of the first lumen, and the second lumen. A third opening is provided at one end on the distal side of the second lumen, a fourth opening is provided at the other end on the proximal side of the second lumen, and the first opening is distal to the third opening. The second opening may be disposed further to the distal side than the fourth opening. In this configuration, the distal end of the first lumen is located more distally than the distal end of the second lumen. This facilitates delivery of the catheter to the lesion along the first wire. Furthermore, when the catheter is fixed by using the first wire arranged in the first lumen and the stenosis portion is penetrated by the second wire arranged in the second lumen, the catheter can be firmly fixed. .

In one embodiment, the first marker and the second marker are formed of a material that is disposed at a position surrounding the first lumen and is opaque to radiation, the first marker having a first opening and a third opening. The second marker may be disposed proximal to the third opening and distal to the second opening. With this configuration, when the catheter is operated based on the radiation transmission image, the position of the first opening can be accurately grasped with the first marker and the position of the second opening can be accurately grasped with the second marker.

According to one aspect of the present invention, it is possible to provide a catheter capable of suppressing breakage of a lumen caused by a wire.

FIG. 1 is a diagram illustrating a cross-sectional configuration of a catheter according to an embodiment. 2A is a diagram showing a cross-sectional configuration along the line aa in FIG. 1, and FIG. 2B is a diagram showing a cross-sectional configuration along the line bb in FIG. FIG. 3 is a diagram illustrating a cross-sectional configuration of the second shaft according to the embodiment. Drawing 4 is a sectional view showing the state where the 2nd wire is located in the 2nd lumen concerning one embodiment. FIG. 5 is a diagram illustrating a cross-sectional configuration of a catheter according to an embodiment. FIG. 6 is a diagram illustrating a cross-sectional configuration of a catheter according to an embodiment. FIG. 7 is a diagram illustrating a cross-sectional configuration of a catheter according to a comparative example.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the description of the drawings, the same or equivalent elements will be denoted by the same reference numerals, and redundant description will be omitted.

The catheter according to an embodiment of the present invention is a penetrating catheter used for the treatment of resuming blood flow by passing a wire through the stenosis portion of the blood vessel when treating the stenosis portion of the blood vessel. In the following description, as shown in FIG. 1, the side where the two lumens are arranged in parallel (the end on the left side in the figure) is distal, the opposite side (the end on the right side in the figure) is proximal, It is defined as

A catheter according to an embodiment of the present invention includes a first wire and a shaft through which a second wire having a bent portion at the tip is passed. The shaft includes a first lumen and a second lumen. The first wire passes through the first lumen. The first lumen is formed by the first wall surface. The second wire passes through the second lumen. The second lumen is formed by the second wall surface. The first lumen is disposed only on the distal side of the catheter, and the second lumen is disposed from the distal side to the proximal side of the catheter. The first lumen and the second lumen are arranged side by side in the longitudinal direction. A portion separating the first lumen and the second lumen is a partition wall. The major axis of the first lumen and the second lumen, that is, the longitudinal axis is preferably parallel. The wall surface is the inner surface of the shaft. The lumen is the lumen of the tubular shaft. The outer surface of the shaft is the outer surface of the shaft. The outer shell of the shaft is a portion excluding the lumen of the shaft.

The shaft used for the catheter according to the embodiment of the present invention may be formed by connecting different shafts on the way, or may be constituted by a single shaft that is seamless from the distal end to the proximal end. . A catheter according to an embodiment of the present invention includes a distal shaft (second shaft) 5 in which a first lumen 20 and a second lumen 22 are formed, and a second lumen 22 as in the catheter shown in FIG. The proximal shaft (first shaft) 3 on which the second lens 22 is formed may be connected so that the second lumen 22 is connected. Alternatively, the catheter according to an embodiment of the present invention may have a configuration in which a shaft that provides a first lumen and a shaft that provides a second lumen are aligned and joined in parallel along the longitudinal direction.

The catheter according to an embodiment of the present invention may partially have a double tube structure. In particular, the proximal side of the first lumen is preferably a double tube structure.

The wire that passes through the lumen is used to enter the stenosis of the blood vessel and guide the catheter to the target site. The first wire is a guide wire for entering a stenosis of a blood vessel or guiding a catheter to a target site. The first wire is disposed in the first lumen. The second wire is a wire that enters the narrowed portion of the blood vessel. The second wire is disposed in the second lumen. The diameter and length of the wire can be appropriately selected according to the catheter to be inserted. The material constituting the wire is preferably a metal, and examples thereof include tungsten, nickel titanium alloy, and stainless steel. In particular, it is preferably formed of a material that does not transmit X-rays (radiation), such as platinum, gold, or an alloy containing these.

As shown in FIG. 1, the tip 9a of the second wire 9 has a bent shape. The bent shape is formed by providing a bending point. The bending part of a wire means the part from the front-end | tip of a wire to a bending point. The bending angle is preferably 5 degrees or more and 90 degrees or less. The length from the forefront of the second wire to the bending point is preferably from 0.5 mm to 50 mm. The number of bending points is preferably one or two, and can be appropriately selected according to the size of the lesion. When the wire is viewed from the distal side to the proximal side, the bends will be arranged non-parallel to the longitudinal axis of the wire.

The cross section orthogonal to the longitudinal direction of the lumen through which the wire of the catheter according to one embodiment of the present invention passes can be a circle, an ellipse, a polygon, an indeterminate shape, or a combination of these shapes. . In the catheter according to an embodiment of the present invention, the first point on the second wall surface where the distance between the outer surface of the shaft and the second wall surface is the smallest in the cross section orthogonal to the longitudinal direction of the shaft is the first point described below. It does not overlap with the straight line. The first straight line is a longest portion connecting two predetermined points on the second wall surface. There may be a plurality of first straight lines on the cross section.

Generally, when a bent portion of a wire having a bent tip contacts the wall surface of the shaft, there is a problem that the tip of the bent portion easily breaks through the wall surface of the shaft. Since the tip of the wire is thin, it is easy to break through the wall surface of the shaft. In particular, when the bent portion comes into contact with the wall surface of the shaft, a force is applied from the bent portion to the tip of the shaft, and the tip of the wire easily breaks through the wall surface of the shaft. A catheter used for blood vessel treatment is formed as thin as possible so that a thin blood vessel can be reached. Therefore, it is preferable that the shaft and the lumen are also thin. Since the bent portion of the wire is formed by bending a straight wire, the ratio of the wire occupying the cross-sectional area in the cross section orthogonal to the longitudinal direction is larger in the bent portion than in the straight case. Therefore, when the bent portion becomes long, the tip of the wire is likely to come into contact with the wall surface. Further, when the bent portion becomes longer, when the wire passes through the lumen, the tip of the wire and / or the bent portion advances while rubbing the wall surface or expanding the wall surface. Further, according to observations by the inventors, the bent portion of the wire often passes so as to select a portion having the longest distance in the cross section of the lumen. Further, the portion where the outer shell portion of the shaft is thin is a portion where the distance between the lumen and the outer surface is short, and the shaft is easily broken when the tip and / or the bent portion of the wire come into contact with each other.

In the catheter according to an embodiment of the present invention, the portion having the smallest distance from the outer surface of the wall surface (second wall surface) of the second lumen through which the catheter having the bent portion passes has the longest distance in the cross section of the second lumen. It does not coincide with the first straight line that is a part. That is, the thinnest part is not located on the first straight line or its extension. In the catheter which concerns on one Embodiment of this invention, the front-end | tip and bending part of a 2nd wire are arrange | positioned in the 1st linear part with the longest distance in the cross section of a lumen | rumen. For this reason, the tip and / or the bent portion of the wire are unlikely to contact the wall surface. Furthermore, in the cross section, the first straight line does not overlap with the thinnest part with the outer surface of the second lumen, so even if the tip and / or the bent part of the second wire contact the second wall surface, it breaks through the wall surface. Thus, the wire can be prevented from protruding from the catheter. Examples of such cross-sectional shapes include various cross-sections shown in FIGS. 6 (a) to 6 (e). Each of the cross-sectional shapes is a shape in which the longest portion of the lumen cross section does not overlap the portion where the distance between the outer surface of the shaft and the wall surface of the lumen is the shortest. In FIG. 6A, the first lumen 20 formed by the first wall surface is provided side by side with the second lumen 22 formed by the second wall surface across the partition wall. The first point P6 on the second wall surface where the distance between the outer surface of the shaft and the second wall surface is the thinnest is overlapped with the longest first straight line D1 connecting two predetermined points P1 and P2 on the second wall surface. It is in a position that cannot be.

FIG. 7 is an example of a cross section of a lumen of a catheter according to a comparative example. In the shaft 50 shown in FIG. 7A, the longest first straight lines D <b> 11 and D <b> 12 connecting two predetermined points on the second wall surface are diagonal lines of the second lumen 54. The first points P11 and P12 on the second wall surface where the distance between the outer surface of the shaft and the second wall surface is the thinnest are the two apexes on the lower side when the first lumen 52 is on the upper side. Since the first point is located on the first straight line, when the tip or the bent portion of the second wire arranged on the first straight line comes into contact with the wall surface, the lumen is moved from the first point having a short distance from the outer surface. There is a risk of damage. In the shaft 50 shown in FIG. 7B, the first straight line is the diameter of the second lumen 54. The first point is the lowest point on the circumference when the first lumen 52 is on the upper side. Similarly to FIG. 7A, since the first point is located on the first straight line, when the tip and / or the bent part of the second wire arranged on the first straight line comes into contact with the wall surface, the outer surface The lumen may be damaged from the first point having a short interval.

As one embodiment of the present invention, in the cross section orthogonal to the longitudinal direction of the catheter, the first lumen is disposed at a position not overlapping the first straight line, and the cross-sectional shape of the second lumen is the first point. It is preferable that the distance of the second straight line, which is a straight line connecting the second points shown below, is shorter than the distance of the first straight line. The second point is a point on the second lumen and is located at a position where the distance between the partition walls, which is a portion between the first lumen and the second lumen, is the shortest. By arranging the first lumen at a position that does not overlap the first straight line, even when the second wire in the second lumen breaks through the inner wall of the second lumen, the second wire contacts the first lumen. Can be prevented. There may be a plurality of second straight lines on the cross section.

As described above, the first point is a point on the second lumen and is located at a position where the distance between the outer surface of the shaft and the second lumen is the shortest. When the first point is on the lower side in the vertical direction, the second point on the partition wall side is located on the upper side. The second straight line is a straight line connecting the first point and the second point. Therefore, a 2nd straight line is a straight line which connects the location where the space | interval of a partition and an outer surface, and a 2nd lumen becomes the shortest. The first straight line is the longest straight line on the cross section of the second lumen. The second straight line is preferably shorter than the first straight line. Thereby, in one Embodiment of this invention, it is a structure where the part with a thin wall surface does not become the longest part.

The bent part of the second wire is arranged at the longest position of the lumen on the cross section. Such an arrangement is a stable arrangement state of the bent portion. Therefore, it can be structurally avoided that the tip and / or the bent portion of the second wire come into contact with the thin wall portion. Examples of such cross-sectional shapes include various cross-sections shown in FIGS. 6 (a) to 6 (e). From the positional relationship between the first point and the second point, in one embodiment, the cross section of the second lumen is often horizontally long. For example, as shown in FIG. 3, the cross section orthogonal to the longitudinal direction of the second lumen 22 is substantially D-shaped, and the flat portion can be the first lumen side. In one embodiment, the cross-sectional shape of the second lumen is preferably a flat shape such as an elliptical shape, a rectangular shape, a rhombus shape, or a barrel shape. In FIG. 6A, the first lumen 20 is arranged at a position that does not overlap with the first straight line D1 extension line. Furthermore, the length of the second straight line D3 connecting the first point P6 and the second point P5 on the second wall surface where the partition wall is the thinnest is shorter than the length of the first straight line D1.

FIG. 7 is an example of a cross section of a lumen of a catheter according to a comparative example. In FIG.7 (b), the 1st lumen | rumen is arrange | positioned on extension of a 1st straight line. The second point is the lowest point on the circumference when the first lumen is on the upper side. Therefore, the second straight line is a diameter connecting the uppermost part and the lowermost part of the circular second lumen, and coincides with the first straight line. Because of this structure, when the tip and / or bent part of the second wire comes into contact with the wall surface, the partition wall may be damaged, or the lumen may be damaged from the first point having a short distance from the outer surface. There is.

The cross-sectional shape of the first lumen may be the same as the shape of the second lumen. In that case, you may use the wire which has a bending part at the front-end | tip as a 1st wire.

As an embodiment of the present invention, the thickness of the thinnest part of the partition wall is the thinnest part between the first wall surface and the outer surface of the shaft, or the thinnest part between the second wall surface and the outer surface of the shaft. It is preferable that it is smaller than either one of these thicknesses. It may be smaller than both. Since the bent portion of the wire has a high possibility of breaking through a thinner portion, this configuration can prevent the bent portion of the wire from breaking through the outer surface of the shaft. In one embodiment of the present invention, the partition can be made small so that the wire does not protrude out of the shaft.

As an embodiment of the present invention, in the cross section orthogonal to the longitudinal direction, the size of the cross section of the shaft is preferably 0.5 mm or more and 1.5 mm or less. The size of the cross section of the shaft refers to the distance between the first point on the outer periphery of the shaft and the second point on the outer periphery facing it. Similarly, the cross-sectional size of the first lumen is preferably 0.25 mm or more and 0.6 mm or less. The length of the first straight line is preferably 0.3 mm or greater and 0.8 mm or less. The length of the second straight line is preferably 0.25 mm or greater and 0.7 mm or less. The length of the partition wall is preferably 0.01 mm or more and 0.12 mm or less. The partition walls and the distance between the outer surface and the lumen can be suitably selected according to the size of the required shaft and lumen.

In the catheter according to an embodiment of the present invention, it is possible to prevent the lumen from being damaged by the wire without having to thicken the shaft through which the wire having the bent portion passes. As a result, the flexibility of the catheter shaft can be ensured, and the operability can be improved as compared with the case where the thickness of the shaft is increased.

As one embodiment of the present invention, the catheter shaft is preferably formed of a flexible material. As a result, the catheter easily deforms following the curvature of the blood vessel, and even when the catheter contacts the blood vessel, the blood vessel is not easily damaged. The material constituting the shaft is preferably a thermoplastic resin material, for example, a polyolefin resin material. For example, polyamide, high density polyethylene and the like may be used. When the shaft is configured by connecting a plurality of tubular members, or when the shaft has a layer structure, the material of each member may be the same or different. In particular, when the shaft has a layered structure, the material forming the outer surface of the shaft and the material forming the inner surface (wall surface) can be different.

As one embodiment of the present invention, the slipperiness of the material forming the inner surface can be higher than the slipperiness of the material forming the outer surface. For example, the inner surface material can be a material having a smaller coefficient of friction than the outer surface material. A preferred material combination is polyamide elastomer and high density polyethylene. Alternatively, by using the same material and sliding the inner surface of the shaft, the sliding property of the inner surface may be improved.

As an embodiment of the present invention, the elastic modulus of the material forming the outer surface of the shaft may be lower than the elastic modulus of the material forming the inner surface. A preferred material combination is polyamide elastomer and high density polyethylene. By increasing the slipperiness of the inner surface of the shaft, that is, the lumen, the wire can move smoothly without being caught on the wall surface. Moreover, the softness | flexibility of a shaft can be improved by using the material of the outer surface of a shaft with a low elastic modulus.

As an embodiment of the present invention, as shown in FIGS. 5 (a) and 5 (b), the shaft of the catheter is placed on the portion including the thinnest portion between the second wall surface and the outer surface. Reinforcing layers 27 and 29 made of a material having higher strength than the material forming the outer surface may be provided. The reinforcing material is disposed so as to be embedded in the shaft. The reinforcing material is preferably not exposed to the lumen and the outer surface. Resin or a metal is mentioned as a material of a reinforcement layer, A metal is preferable. When the material of the shaft is a resin, the material of the reinforcing layer can be, for example, a metal, such as stainless steel. The shape of the reinforcing layer includes a linear shape, a braided shape, a coil shape, and the like, and the cross section of each strand can be selected as appropriate, such as a flat wire, a rectangular wire, or a round wire. The reinforcing layer is preferably provided around the second lumen. A partition wall is also included around the second lumen where the reinforcing layer is provided. By providing the reinforcing layer, it is possible to further suppress the second wire having the bent portion from breaking through the second lumen and penetrating to the outer surface or the first lumen. In order to prevent the first wire from breaking through the first lumen, a reinforcing layer may be provided around the first lumen.

As one embodiment of the present invention, it is preferable that the distal opening of the first lumen of the catheter is disposed more distally than the distal opening of the second lumen. This is for facilitating fixation of the catheter by the first guide wire. Moreover, it is preferable that the proximal opening of the first lumen of the catheter is disposed more distally than the proximal opening of the second lumen. This is because the first lumen is preferably shorter than the second lumen when the catheter is used as a rapid exchange type catheter.

As one embodiment of the present invention, the distal end surface of the second tube is preferably inclined. Such an inclination is an inclination having a predetermined angle with respect to the longitudinal direction of the second tube. In particular, the distal end surface of the second tube preferably has an upper end on the distal side and a lower end on the proximal side when the first tube is in the upward direction. The end face may be continuously inclined, stepped or curved. The end face is not inclined and may be an end face orthogonal to the longitudinal direction of the tube.

As an embodiment of the present invention, the catheter preferably has a marker formed of a material that is opaque to radiation. With such a marker, the position of the catheter can be grasped during the procedure. In particular, the markers are preferably provided at two locations, the distal side and the proximal side, across the distal opening of the second lumen. Thereby, the position of the distal side mechanism of the second lumen can be easily grasped. Examples of the material for the marker include platinum (Pt), iridium (Ir), and alloys containing these. The marker is preferably an annular shape surrounding the lumen. The marker is preferably arranged to be embedded inside the shaft.

As shown in FIG. 1, a hub 15 may be connected to the proximal end of the first shaft 3. The hub is for smoothly introducing the second wire having a bent tip into the second lumen through an internal tapered structure. The hub is preferably connected to the shaft by an adhesive. Examples of the adhesive include urethane-based adhesion.

The catheter shaft can be formed by extrusion molding of a resin material. The molding conditions should be appropriately selected as necessary.

(Example)
As an example of an embodiment of the present invention, a catheter 1 shown in FIG. 1 includes a first shaft 3 on the proximal side and a second shaft 5 on the distal side. The first shaft 3 includes an outer tube 11 and an inner tube 13. The second shaft 5 includes a first tube 24 and a second tube 26. The second tube 26 and the inner tube 13 are continuous. The first lumen 20 is a lumen of the first tube 24. The second lumens 12 and 22 are lumens of the inner tube 13 and the second tube 26. In FIG. 1, the first lumen 20 is disposed on the distal side, and the second lumens 22 and 12 are disposed on the distal side to the proximal side. The first wire 7 passes through the first lumen 20. The second wire 9 passes through the second lumens 12 and 22.

The catheter 1 is connected to the distal end of the first shaft 3 and a part of the proximal end of the second shaft 5. The catheter 1 is inserted into the blood vessel from the distal end of the second shaft 5. The proximal side of the first shaft 3 is a portion operated by the operator of the catheter 1. As shown in FIG. 2A, the first shaft 3 has a double tube structure in which the inner tube 13 is disposed inside the outer tube 11.

The outer tube 11 is made of polyamide. As shown in FIG. 2B, the cross section orthogonal to one direction of the outer tube 11 is an annular shape. The inner tube 13 is made of high density polyethylene. The cross section orthogonal to one direction of the inner tube 13 is annular. The cross section of the second lumen 12 that is not parallel to the first lumen 20 is circular.

In the present embodiment, the first shaft 24 and the second tube 26 are integrally held or integrated by the main body 28 in the second shaft 5. The main body 28 is formed of a material having a lower elastic modulus than the first tube 24 and the second tube 26. In the present embodiment, the main body 28 is made of polyamide elastomer (PAE). The main body 28 constitutes the outline of the second shaft 5. The outer peripheral surface of the main body 28, that is, the outer surface 28 a is the outer surface of the second shaft 5.

2A and 3, the main body 28 covers the first tube 24 and the second tube 26. The first tube 24 and the second tube 26 are arranged in parallel at a predetermined interval in a cross section orthogonal to the longitudinal direction of the main body 28. The second tube 26 is arranged so that the straight portion of the cross section faces the first tube 24. As a result, the first lumen 20 and the second lumen 22 are arranged in parallel with the partition wall 25 interposed therebetween. In one embodiment, the septum 25 includes the thickness of the first tube 24, the thickness of the second tube 26, and the thickness of the body 28. That is, the partition wall 25 is formed between the first wall surface that forms the first lumen 20, that is, the inner surface 24 a of the first tube 24, and the second wall surface that forms the second lumen 22, that is, the inner surface 26 a of the second tube 26. Part.

The first tube 24 is made of high density polyethylene. The cross section perpendicular to the longitudinal direction of the first lumen 20 is circular. The first tube 24 is made of a material that is more slippery than the main body 28 described later. The second tube 26 is made of high density polyethylene. Similar to the first tube 24, the second tube 26 is formed of a material that is more slippery than a main body 28 described later. The second tube 26 is connected to the inner tube 13 of the first shaft 3. The second lumen 12 and the second lumen 22 of the inner tube 13 are continuous. The cross section perpendicular to the longitudinal direction of the second lumen 22 in the portion parallel to the second lumen 12 is substantially D-shaped, in other words, a shape in which a circle is partially cut away, and a straight portion and an arc-shaped portion including.

The first wire 7 and the second wire 9 are made of stainless steel. As shown in FIG. 1, the tip 9a of the second wire 9 has a bent shape, and is bent 45 ° when the longitudinal direction is 0 °. The length from the forefront of the second wire 2 to the bending point is 1 mm.

A hub 15 is connected to the proximal end of the first shaft 3. The hub 15 is made of a styrene-butadiene copolymer. The hub 15 is fixed to the first shaft 3 with adhesives 17a and 17b. Since the proximal side of the catheter of this embodiment has a double tube structure, the proximal end of the outer tube 11 and the proximal end of the inner tube 13 are bonded to the hub 15 with adhesives 17a and 17b. . The adhesives 17a and 17b are urethane adhesives. The second lumen 12 of the inner tube 13 communicates with the lumen 15 a of the hub 15. The lumen 15 a of the hub 15 is an introduction part that introduces the second wire 9 into the first shaft 3.

The distal end and the proximal end of the first lumen 20 are provided with a distal opening (first opening) 21a and a proximal opening (second opening) 21b. A distal opening (third opening) 23 a is provided at the distal end of the second lumen 22. A proximal opening (fourth opening) 23 b is provided at the proximal end of the second lumen 12. As shown in FIG. 1, the first opening 21a, the third opening 23a, the second opening 21b, and the fourth opening 23b are arranged in this order from the distal side. In the present embodiment, the proximal opening 21 b of the first lumen 20 is located at a connection portion between the first shaft 3 and the second shaft 5. In the present embodiment, the distal end surface of the second tube 26 is inclined with respect to the plane orthogonal to the longitudinal direction so that the side closer to the first lumen 20 is the distal side and the far side is the proximal side. Yes.

The first tube 24 is provided with a first marker 30 and a second marker 32. In the present embodiment, the first marker 30 and the second marker 32 are made of an alloy containing platinum (Pt) and indium (Ir). The first marker 30 and the second marker 32 have a ring shape and are attached to the first tube 24 so as to surround the first tube 24. The first marker 30 and the second marker 32 are arranged in the longitudinal direction of the first tube 24 with the distal opening (third opening) 23a of the second lumen interposed therebetween. The first marker 30 is disposed distal to the distal opening (third opening) 23a, and the second marker 32 is disposed proximal to the distal opening (third opening) 23a.

As shown in FIG. 3, the first lumen 20 connects the two predetermined points P <b> 1 and P <b> 2 on the inner surface 26 a of the second lumen 22 and is the longest in the cross section orthogonal to the longitudinal direction of the second shaft 5. It arrange | positions in the position which does not overlap with the extension line of 1 straight line D1. In the present embodiment, the first straight line is also defined by two predetermined points P3 and P4. In the present embodiment, the first straight lines D1 and D2 are straight lines connecting the points P1 and P3 that are the ends of the straight part of the inner surface 26a of the second tube 26 and the points P2 and P4 of the arcuate part.

The second lumen 22 has a second point P5 on the inner surface 26a where the partition wall 25 is thinnest and a first point P6 on the inner surface 26a where the space between the outer peripheral surface 28a and the inner surface 26a of the main body 28 is thinnest. The second straight line D3 to be connected is shorter than the first straight lines D1 and D2. With this configuration, as shown in FIG. 4, the bent portion of the second wire 9 moves while being arranged on the first straight line D <b> 1 and the straight line D <b> 2 having the maximum diameter in the second lumen 22.

In this embodiment, the minimum thickness T1 of the partition wall 25 is smaller than the minimum thickness T2 between the inner surface 26a of the second tube 26 and the outer peripheral surface 28a. The thinnest part between the inner surface 26 a and the outer peripheral surface 28 a includes the thickness of the second tube 26 and the thickness of the main body 28.

A method for manufacturing the catheter 1 will be described. In manufacture of the catheter 1 of an Example, the 1st main body tube and the 2nd main body tube which comprise the outer tube 11, the inner tube 13, the 1st tube 24, the 2nd tube 26, and the main body 28 are prepared. Each tube is formed by extrusion molding with a predetermined material. Plasma treatment is performed on the distal side of the first tube 24 and the second tube 26. The plasma treatment is performed for connecting the outer tube 11 and the inner tube 13. Depending on the combination of materials, plasma treatment may or may not be performed.

The first marker 30 and the second marker 32 are attached to the distal side of the first tube 24 at a predetermined interval. The first marker 30 and the second marker 32 are caulked and fixed to the first tube 24. About other embodiment, the fixing method of a marker is not specifically limited, There exist methods, such as adhesion | attachment by an adhesive agent, or winding around the tube of a marker.

ス テ ン レ ス Insert a stainless steel core into the first tube 24. The cross section orthogonal to the longitudinal direction of the core material is circular. Further, a stainless steel core material is inserted into the second tube 26. The cross section orthogonal to the longitudinal direction of the core material is substantially D-shaped. Further, the stainless steel core material inserted into the second tube 26 is inserted into the inner tube 13. In the core material, the distal side of the inner tube 13 is disposed on the proximal side of the second tube 26. The core material inserted into the second tube 26 is inserted to the proximal end of the inner tube 13. The length of the core material may be the same as the length of the tube to be inserted, and it is allowed to be longer or shorter than the tube. The length of the core material can be appropriately selected as necessary. The cross-sectional shape of the core material can be appropriately selected as necessary.

The first tube 24 and the second tube 26 are arranged in parallel. Specifically, the first tube 24 and the second tube 26 are arranged such that the distal end of the second tube 26 is positioned between the first marker 30 and the second marker 32 attached to the first tube 24. Line up. The first main body tube is put on the first tube 24 and the second tube 26. The first body tube has a distal end disposed between the first marker 30 and the second marker 32 and a proximal end coincident with the proximal end of the first tube 24. In addition, the second main body tube is put on a portion on the distal side of the first tube 24 that is not covered with the first main body tube. The second body tube is positioned so that the distal end coincides with the distal end of the first tube 24 and the proximal end abuts the distal end of the first body tube.

The outer tube 11 is put on the inner tube 13. The distal end of the outer tube 11 abuts the proximal end of the first body tube. The butted portion of the first main body tube and the second main body tube and the first main body tube and the outer tube 11 are covered with an olefin-based shrink tube, and the shrink tube is heated. The shrink tube is preferably placed over the area to be heated. Accordingly, the first main body tube and the second main body tube, and the first main body tube and the outer tube 11 are welded and integrated. The first tube 24, the second tube 26, and the inner tube 13 are also welded and integrated. When all the tubes are welded and integrated, the main body 28 of the second shaft is formed. Further, when the shrink tube is heated, the first tube 24 and the second tube 26 are also heated, and the shapes of the inner surface 24a of the first tube 24 and the inner surface 26a of the second tube 26 are changed to the shape of the inserted core material. It is formed. Unlike the case of FIG. 2B, the boundary between adjacent tubes such as the boundary between the main body 28 and the first and second tubes 24 and 26 may become unclear due to heating. As for the heating, the whole may be heated at once, may be heated a plurality of times, may be partially heated, and there may be a time difference in heating.

The hub 15 is connected to the proximal ends of the outer tube 11 and the inner tube 13 by adhesives 17a and 17b. Thereby, the catheter 1 is manufactured. The procedure for manufacturing the catheter shown here may be performed in the order as described, or may be performed in a suitable order. Other procedures may be added or omitted. The heating for welding and integration may be performed by heating all of the heating points at once or sequentially. Alternatively, the end faces may be formed by heating the tubes without abutting each other and cutting the ends after welding.

A method of using the catheter 1 having the above configuration will be described. First, the first wire 7 is inserted into the blood vessel, and the first wire 7 is advanced to the periphery of the lesion site based on the X-ray transmission image. Here, the periphery of the lesioned part refers to the other side of the lesioned part as viewed from the catheter approaching the lesioned part in the blood vessel. Next, the proximal side of the first wire 7 is inserted from the distal side of the first lumen 20 of the second shaft 5, and the catheter is advanced along the first wire 7 to the vicinity of the lesion site. At this time, the first marker 30 and the second marker 32 can be used as marks in the X-ray transmission image.

Subsequently, the second wire 9 having a bent portion formed on the distal end side is inserted from the hub 15 into the inner tube 13 (second lumen 12) of the first shaft 3, and the second wire 9 is inserted into the second lumen of the second shaft 5. Proceed to 22. Furthermore, the 2nd wire 9 is advanced to the periphery of a constriction part. Thereby, the catheter 1 forms a passing portion in the narrowed portion.

As mentioned above, although embodiment of this invention has been described, this invention is not necessarily limited to embodiment mentioned above, A various change is possible in the range which does not deviate from the summary.

DESCRIPTION OF SYMBOLS 1 ... Catheter, 3 ... 1st shaft, 5 ... 2nd shaft, 7 ... 1st wire, 9 ... 2nd wire, 20 ... 1st lumen, 21a ... Distal opening (1st opening), 21b ... Proximal opening (Second opening), 24a ... inner surface (first wall surface), 25 ... partition wall, 12 ... second lumen, 22 ... second lumen, 23a ... distal opening (third opening), 23b ... proximal opening (fourth) Opening), 26a ... inner surface (second wall surface), 30 ... first marker, 32 ... second marker.

Claims (9)

A shaft for passing each of the first wire and the second wire having a bent portion at the tip;
The shaft is
A first lumen formed by a first wall surface through which the first wire passes;
A second lumen formed by a second wall surface and provided side by side with the first lumen and the partition, and passing the second wire;
The first lumen and the second lumen are disposed along a longitudinal direction of the shaft;
In the cross section orthogonal to the longitudinal direction of the shaft, the first point on the second wall surface where the distance between the outer surface of the shaft and the second wall surface is the thinnest is two predetermined points on the second wall surface. The catheter is in a position that does not overlap with the longest first straight line. The first lumen is disposed at a position that does not overlap with an extension line of the first straight line in the cross section.
2. The distance of a second straight line connecting the first point and the second point on the second wall surface where the partition wall is thinnest is shorter than the distance of the first straight line in the cross section. Catheter. The thinnest thickness of the partition is smaller than at least one of the thinnest thickness between the first wall surface and the outer surface and the thinnest thickness between the second wall surface and the outer surface. Item 3. The catheter according to Item 1 or 2. The catheter according to any one of claims 1 to 3, wherein a material forming the first wall surface and the second wall surface has higher slipperiness than a material forming the outer shell of the shaft. The catheter according to any one of claims 1 to 4, wherein a material forming the outer shell of the shaft has a lower elastic modulus than a material forming the first wall surface and the second wall surface. 6. The reinforcing layer according to claim 1, wherein a reinforcing layer having a strength higher than that of a material forming the outer shell of the shaft is provided in a part including the thinnest portion between the second wall surface and the outer surface. The catheter according to one item. The catheter according to claim 6, wherein the reinforcing layer is provided around the second lumen. A first opening is provided at one end on the distal side of the first lumen, and a second opening is provided at the other end on the proximal side of the first lumen;
A third opening is provided at one end of the second lumen on the distal side, and a fourth opening is provided at the other end on the proximal side of the second lumen;
The first opening is disposed on the distal side of the third opening;
The catheter according to any one of claims 1 to 7, wherein the second opening is disposed on the distal side of the fourth opening. A first marker and a second marker which are arranged at a position surrounding the first lumen and are formed of a material which is opaque to radiation;
The first marker is disposed between the first opening and the third opening;
The catheter according to claim 8, wherein the second marker is disposed on the proximal side with respect to the third opening and on the distal side with respect to the second opening.

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