WO2019012819A1

WO2019012819A1 - Suction catheter

Info

Publication number: WO2019012819A1
Application number: PCT/JP2018/020234
Authority: WO
Inventors: 翠翠李
Original assignee: 株式会社カネカ
Priority date: 2017-07-10
Filing date: 2018-05-25
Publication date: 2019-01-17
Also published as: JP6965348B2; JPWO2019012819A1

Abstract

In order to improve the capacity to suction a thrombus caught on a guide wire, the shape of an edge (3b) forming a suction opening (3a) in a suction catheter (10), when viewed from the bottom side in the vertical direction, is asymmetric, with a virtual line (C) connecting the most distal end position (1a) and the most proximal end position (1b) serving as the axis of symmetry.

Description

Aspiration catheter

The present invention relates to a suction catheter.

Conventionally, in the case where a stenosis or occlusion occurs in a vessel such as a blood vessel, and in the case where the blood vessel is blocked due to a thrombus, a treatment method of aspirating and removing the thrombus is effective. The catheter used for such treatment is called aspiration catheter.

In the treatment using an aspiration catheter, a guide wire is used to guide the aspiration catheter to the vicinity of the aspiration target site in the blood vessel. The suction catheter usually has a suction lumen having a suction port for suctioning a suction target, and a guide wire lumen for inserting a guide wire. Therefore, when the operator inserts the aspiration catheter into the blood vessel and guides it to the aspiration target site in the blood vessel, first, the guide wire is inserted into the blood vessel and the distal end of the guide wire is the aspiration target site Let the clot hold it. This secures a route by the guide wire for the aspiration catheter to reach the aspiration target site. Thereafter, the proximal end of the guidewire is passed through the distal end of the guidewire lumen of the aspiration catheter, and the aspiration catheter is inserted into the blood vessel. The aspiration catheter is moved in the blood vessel along the guide wire to reach the aspiration target site, and the thrombus is aspirated from the aspiration port. Therefore, in the aspiration catheter, the reachability to the lesion site where the foreign object to be aspirated is present and the aspiration performance for aspirating the object as much as possible are simultaneously determined.

Examples of conventional suction catheters include the suction catheters described in

Patent Documents

1 and 2. In the suction catheters described in

Patent Documents

1 and 2, a suction port for suctioning foreign matter such as thrombus is formed to be inclined with respect to the axis of the suction catheter.

International Publication No. 2008/123521 Unexamined-Japanese-Patent No. 2004-222946

Here, when the outside diameter size of the aspiration catheter is increased and the size of the aspiration port is increased, the aspiration catheter has a high aspiration performance, but it is difficult to insert the peripheral region consisting of thin blood vessels. Therefore, there is a limit to increasing the outer diameter of the suction catheter from the viewpoint of peripheral accessibility. In addition, in the case of an aspiration catheter excellent in peripheral reachability, it is difficult to remove a huge thrombus in a peripheral blood vessel because the inner diameter of the aspiration port or aspiration lumen is relatively small.

When the aspiration catheter is inserted into the blood vessel and guided to the aspiration target site in the blood vessel, the guide wire moves along the wall of the blood vessel, not the central portion of the blood vessel, and pierces the thrombus as the aspiration target site to the distal end. Is retained in the thrombus.

As described in

Patent Documents

1 and 2, when the suction port is suctioned using a suction catheter formed to be inclined with respect to the axis of the suction catheter, the thrombus is well suctioned from the suction port. Ru. However, since the guide wire lumen and the suction lumen are disposed in parallel in the suction catheter, the thrombus caught on the guide wire away from the suction port is not sufficiently aspirated. Therefore, in the conventional suction catheters described in

Patent Documents

1 and 2, there is a problem that the thrombus can not be sufficiently suctioned.

One aspect of the present invention aims to provide an aspiration catheter having an improved aspiration performance for thrombi caught on a guide wire.

In order to solve the above-mentioned subject, the suction catheter concerning one mode of the present invention is provided with the suction tube provided with the suction lumen which has a suction part in the distal end, and the suction part is to the axis of the suction tube. A suction catheter having a suction port formed in an inclined manner, and in the suction portion, when the most distal end position is a first position and the most proximal end position is a second position, The direction of the axis is a first direction, the direction of a line passing the second position and perpendicular to the axis is a second direction, and a direction perpendicular to both the first direction and the second direction is a third. As a direction, as viewed from the second position in the second direction, the shape of the edge forming the suction port is asymmetric with respect to a first line connecting the first position and the second position. It is characterized by

According to one aspect of the present invention, there is an effect that the suction performance for the thrombus caught by the guide wire is improved.

The schematic structure of the suction catheter used as the premise of embodiment of this invention is shown, (a) is a side view, (b) is the sectional view on the AA line. The schematic structure of the suction catheter which concerns on Embodiment 1 of this invention is shown, (a) is a front view which shows the schematic structure seen from the distal end side, (b) shows the schematic structure seen from the side. It is a side view and (c) is a bottom view showing a schematic structure seen from the lower side. It is a side view which shows the modification of the suction catheter which concerns on Embodiment 1 of this invention, and shows the schematic structure seen from the side. The schematic structure of the distal end side of the suction catheter which concerns on Embodiment 2 of this invention is shown, (a) is a front view which shows the schematic structure seen from the distal end side, (b) is seen from the side (C) is a bottom view showing the schematic configuration viewed from the lower side, and (d) is a perspective view showing the schematic configuration viewed from the distal end side. e) is a cross-sectional view showing a schematic configuration on the distal end side. It is a front view which shows the modification of the suction catheter which concerns on Embodiment 2 of this invention, and shows the schematic structure seen from the distal end side.

(Configuration of aspiration catheter that is the premise of this embodiment)
First, the configuration of the suction catheter which is the premise of the present embodiment will be described. FIG. 1 shows a schematic configuration of a suction catheter 11 as a premise of the present embodiment, FIG. 1 (a) is a side view, and FIG. 1 (b) is a cross-sectional view.

As shown in FIG. 1A, the suction catheter 11 includes a suction tube 1 constituting a suction lumen and a guide wire tube 2 constituting a guide wire lumen. At the distal end of the suction tube 1, a suction unit 3 is provided. The suction unit 3 has a suction port 3a for suctioning a suction target such as a thrombus. The suction port 3 a is provided to be inclined with respect to the axis of the suction tube 1. Here, the suction target side in the suction catheter is the distal end side or the distal side, and the opposite side is the proximal end side or the proximal side.

The guide wire tube 2 is provided on the suction portion 3 side of the suction tube 1, that is, on the distal side. Further, the distal end of the guide wire tube 2 is located on the distal side of the most distal end position (the most distal end position 1a shown in FIG. 2) in the suction part 3. The length of the guide wire tube 2 is, for example, 120 mm. The length of the suction tube 1 is, for example, 140 cm, and the diameter of the tube is, for example, 1.1 mm. The diameter of the guide wire tube is, for example, 0.4 mm. The distal end of the guide wire tube 2 may be located at the same position as the position of the most distal end of the suction unit 3 or on the proximal side of the same.

In addition, as shown in (b) of FIG. 1, the wall portion of the suction tube 1 is a laminated structure including the inner layer 12, the reinforcing layer 13, and the covering layer 14. A fluorine resin or high density polyethylene is used as the resin constituting the inner layer 12. Specific examples of the resin constituting the inner layer 12 include polytetrafluoroethylene (PTFE), tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer (PFA), tetrafluoroethylene / hexafluoropropylene copolymer (FEP), tetrahedron Examples include fluoroethylene-ethylene copolymer (ETFE), polyvinylidene fluoride (PVDF), polychlorotrifluoroethylene (PCTFE) and the like.

The reinforcing layer 13 has a braided shape in which strands are alternately knitted in a mesh shape. Examples of the material of the strands of the reinforcing layer 13 include synthetic fibers such as nylon fibers, and metals such as Ti—Ni and stainless steel.

The covering layer 14 is a layer covering the inner layer 12 and the reinforcing layer 13 in a braided shape. An elastomer is used as the resin constituting the covering layer 14. As a specific example of resin which comprises the coating layer 14, a polyamide elastomer, a polyester elastomer, a polyolefin elastomer etc. are mentioned. The total number, thickness and material of the laminated structure of the tube can be appropriately designed according to the required function. For example, a structure with only one layer, a structure in which the inner layer 12, the reinforcing layer 13, and the covering layer 14 are the same material, a structure without the reinforcing layer 13, and the like can be mentioned as embodiments of the present invention.

Embodiment 1
The suction catheter according to the present embodiment is characterized by the structure of the distal end side of the suction catheter 11 shown in FIG. (A) of FIG. 2 is a front view showing a schematic configuration as viewed from the distal end side of the suction catheter 10 according to the present embodiment. (B) of FIG. 2 is a side view showing a schematic configuration as viewed from the side. (C) of FIG. 2 is a bottom view which shows the schematic structure seen from lower side.

In the suction catheter 10, the suction unit 3 has a suction port 3a formed so as to be inclined with respect to the axis X of the suction tube 1. Therefore, the suction portion 3 on the distal end side of the suction catheter 10 includes the most distal end position 1a (first position) at the most distal end and the most proximal end position 1b at the most proximal end (a first position). There is a second position).

Within a blood vessel, a guidewire is often placed along the vessel wall. When the guide wire is disposed along the blood vessel wall, the most distal end position 1a adjacent to the guide wire tube 2 is disposed closest to the blood vessel wall at the suction port 3a. On the other hand, the nearest end position 1b is arranged at the position farthest from the blood vessel wall.

The shape in the vicinity of the most distal end position 1a in the suction portion 3 is a shape inclined downward toward the most proximal end position 1b. Further, the shape in the vicinity of the most proximal end position 1b in the suction part 3 is a shape inclined upward to the most distal end position 1a. Assuming that the vicinity of the most distal end position 1a is a nose, the vicinity of the most proximal end 1b can be regarded as a jaw.

Further, in the present specification, with the axis X of the suction tube 1 as a reference, the most distal end position 1a side in the suction part 3 is the upper side, and the opposite side to the upper side is the lower side. The upper side can also be said to be the side on which the guide wire tube 2 in the suction catheter 10 is provided. And it can be said that the side opposite to the guide wire tube 2 is the lower side.

The direction of the axis X of the suction tube 1 is the longitudinal direction (first direction), and the direction of the straight line passing through the most proximal end position 1b of the suction portion 3 and orthogonal to the axis X is the vertical direction (second direction). The direction perpendicular to both the longitudinal direction and the vertical direction is the width direction (third direction). In addition, it can be said that the up-down direction is the direction of the perpendicular of the axis X passing through the nearest end position 1b.

In the suction catheter 10 according to the present embodiment, as shown in (c) of FIG. 2, the shape of the edge 3 b forming the suction port 3 a is the most distal end position 1 a when viewed from the lower side in the vertical direction. An imaginary line C (first line), which is a straight line connecting the nearest end position 1b, is asymmetrical with the axis of symmetry.

Here, two parts of the edge 3b divided on the basis of the virtual line C are taken as a first edge 3c and a second edge 3d. At this time, as shown in FIG. 2B, the shape of the edge 3b forming the suction port 3a is such that the first edge 3c and the second edge 3d are at least viewed from the width direction (third direction). There is a part that does not overlap in one copy.

The edge shape of the suction port 3a shown in (a) to (c) of FIG. 2 forms the suction port 3a by cutting away the welded body of the suction tube 1 and the guide wire tube 2 and the distal end of the suction tube 1. At this time, it is possible to form by setting the moving direction etc. of the blade member used for cutting.

For example, by moving the knife-like blade member with respect to the suction tube 1 while moving the blade tip in the trajectory along the imaginary line C while keeping the cutting edge inclined with respect to the axis X, suction The mouth 3a is formed. At this time, by keeping the cutting edge inclined with respect to both the width direction and the direction (longitudinal direction) of the axis X, the blade member is moved to the distal end side along a trajectory along the imaginary line C The edge shape of the suction port 3a shown in (a) to (c) of FIG. 2 is formed.

Further, as shown in (a) to (c) of FIG. 2, the guide wire tube 2 having the guide wire lumen B is provided in parallel with the axis X of the suction tube 1. When the suction catheter 10 is viewed from the distal end side in the longitudinal direction (in FIG. 2A), the axis Y of the guide wire tube 2, the most distal end position 1a and the most proximal end position 1b are the same straight line It is arranged to line up on the line. Here, “colinearly” means the axis Y, the most distal end position 1a, and the most end position 1b within the position measurement limit of the axis Y, the most distal end position 1a, and the most proximal end position 1b. Means aligned on the same straight line. Here, the "position measurement limit" is the limit of measurement error of the measurement means for measuring each position of the axis Y, the most distal end position 1a and the most proximal end position 1b, and the position measurement of the measurement means Determined by accuracy.

By the way, the suction catheter 10 is configured to be inclined with respect to the axis X of the suction tube 1 and the suction port 3a is provided. In such a configuration, when the shape of the edge 3b forming the suction port 3a is symmetrical with respect to the imaginary line C as viewed from below in the vertical direction (for example, in the case of the configurations described in Patent Documents 1 and 2) The suction pressure at the suction port 3a has a symmetrical distribution with the imaginary line C as the axis of symmetry. Then, the suction pressure at the most proximal end position 1b is the highest, and the suction pressure at the most distal end position 1a is the lowest. As a result, in the region surrounded by the edge 3b of the suction port 3a, the region on the farthest end position 1a side (upper side) and the latest with the perpendicular D extending in the width direction passing through the middle point O of the imaginary line C A difference in suction pressure occurs between the region on the side of the end position 1 b (lower side). When the shape of the edge 3 b of the suction port 3 a viewed from the longitudinal direction is a circle, for example, the middle point O can be said to be the center of the extended circle.

Consider a case where a thrombus having the same size as that of the suction port 3a and having a large amount of fibrous matter is sucked into the suction port 3a in a state where such a difference in suction pressure is generated. In this case, the thrombus present in the area on the side of the most proximal end position 1b is preferentially aspirated by the difference in suction pressure, and the thrombus present in the area on the side of the most distal end position 1a remains in the blood vessel. Therefore, when the shape of the edge 3b forming the suction port 3a is symmetrical with respect to the imaginary line C as viewed from the lower side in the vertical direction, the thrombus present in the region on the farthest distal end position 1a side is aspirated As a result, the ability to aspirate blood clots caught on the guide wire is extremely low.

Then, the thrombus present in the area of the most proximal end position 1b is aspirated and removed to some extent from the suction port 3a, thereby generating a space in the blood vessel. At this time, the thrombus caught on the guide wire moves to this space, and becomes a large clump through the region on the most proximal end position 1b side in the suction port 3a. For this reason, there is a possibility that the suction lumen A may be blocked by such a large clot thrombus.

According to the suction catheter 10 according to the present embodiment, as shown in (b) and (c) of FIG. 2, the shape of the edge 3 b forming the suction port 3 a is a virtual line when viewed from the lower side in the vertical direction It is asymmetric with C as the axis of symmetry. As a result, the suction pressure distribution at the suction port 3a is disturbed. Therefore, the suction pressure distribution at the suction port 3a is asymmetrical with the imaginary line C as the axis of symmetry, and between the region on the most distal end position 1a and the region on the most proximal position 1b side with reference to the perpendicular D The suction pressure difference becomes smaller. As a result, in the suction catheter 10 according to the present embodiment, the suction pressure in the region on the most distal end position 1a side of the suction port 3a is larger than that in the conventional suction catheter. For this reason, the thrombus present on the farthest distal end position 1a side is easily aspirated, and the aspiration performance for the thrombus caught on the guide wire is improved. Furthermore, it is possible to realize the aspiration catheter 10 in which the occlusion of the aspiration lumen A due to the thrombus hardly occurs.

Further, in order to increase the suction pressure in the region on the side of the most distal end position 1a in the suction port 3a, the length of the first edge 3c is preferably more than one time the length of the second edge 3d, It is three times or less, more preferably 1.2 times or more and 1.8 times or less the length of the second edge 3d.

(Modification)
A modification of the configuration shown in (a) to (c) of FIG. 2 in the configuration of the suction catheter 10 according to the present embodiment will be described. FIG. 3 is a side view showing a schematic configuration of the suction catheter 10A as a modification as viewed from the side.

The suction catheter 10A is different from the configuration shown in (a) to (c) of FIG. 2 in the shape of the edge 3b of the suction port 3a. As shown in FIG. 3, when viewed in the width direction, the shape of the edge 3 b formed of the first edge 3 c and the second edge 3 d is curved toward the proximal end side relative to the imaginary line C.

With such a configuration, even if the suction catheter 10A has a small diameter with a small dimension in the vertical direction, it is possible to secure the dimension of the suction port 3a capable of sucking a thrombus.

Second Embodiment
Hereinafter, other embodiments of the present invention will be described in detail. FIG. 4 shows a schematic configuration of the distal end side of the suction catheter 10B according to the present embodiment, and FIG. 4 (a) is a front view showing a schematic configuration as viewed from the distal end side. (B) is a side view showing a schematic configuration as viewed from the side, (c) in FIG. 4 is a bottom view showing a schematic configuration as viewed from the lower side, and (d) in FIG. 4 is a distal end It is a perspective view which shows schematic structure seen from the side, and (e) of FIG. 4 is sectional drawing which shows the schematic structure by the side of a distal end. In addition, about the member which has the same function as the member demonstrated in the said embodiment for convenience of explanation, the same code | symbol is appended and the description is abbreviate | omitted.

In the suction catheter 10B according to the present embodiment, as shown in FIG. 4C, the shape of the edge 3b forming the suction port 3a is asymmetrical with the imaginary line C as the axis of symmetry when viewed from the lower side in the vertical direction In that the second embodiment is the same as the first embodiment.

In the suction catheter 10B according to the present embodiment, as shown in (a) of FIG. 4, when viewed from the distal end side in the longitudinal direction, the shape of the edge 3b forming the suction port 3a is an imaginary line C as an axis of symmetry , And are different from the first embodiment in that the

curved portions

4a and 4b are provided on the edge 3b. The

curved portions

4a and 4b are curved outward with respect to the peripheral edge 3b. In other words, in (a) of FIG. 4 which shows the front view which looked at the suction catheter 10 from the distal end side, the distance between the midpoint O of the virtual line C and the edge 3b is the midpoint O and the most distal end position Portions larger than the distance to 1 a (corresponding to the half length of the imaginary line C) are provided as the

curved portions

4 a and 4 b.

Furthermore, when the edge 3 b is viewed from the distal end side, one of the two

curved portions

4 a and 4 b is the most distal with respect to the perpendicular line D passing through the midpoint O of the imaginary line C. It is arranged at the end position 1a side. The other curved portion 4b is disposed on the side of the nearest end position 1b with reference to the perpendicular line D. The curved portion 4 b is disposed on the opposite side of the curved portion 4 a with reference to the middle point O of the imaginary line C.

Further, as shown in (b) to (e) of FIG. 4, the

curved portions

4a and 4b are provided from the suction port 3a to the side wall 1c of the suction lumen A of the suction tube 1. From the configuration shown in (c) and (d) of FIG. 4, the

curved portions

4 a and 4 b are formed on the side wall 1 c of the suction lumen A, and longitudinally from the distal end side to the proximal end side of the suction port 3 a It can be regarded as a recess extending to the The

curved portions

4a and 4b as the recessed portions may be provided across the side wall 1c of the suction lumen A at least in the portion from the most distal end position 1a to the most proximal end position 1b. For example, the

curved portions

4a and 4b are provided on the side wall 1c of the suction lumen A up to a position of 10 mm from the most proximal end position 1b to the proximal end side.

The suction catheter 10B according to the present embodiment is configured in consideration of the edge shape of the suction port 3a viewed from such a distal end side in the longitudinal direction.

According to the suction catheter 10B according to the present embodiment, as shown in FIG. 4A, the shape of the edge 3b forming the suction port 3a is asymmetrical with the imaginary line C as the axis of symmetry. Therefore, the suction pressure at the suction port 3a has an asymmetric distribution with the imaginary line C as the axis of symmetry. Therefore, in the suction port 3a, a difference in suction pressure occurs between the two areas A1 and A2 divided by the imaginary line C.

Furthermore, when

curved portions

4a and 4b curved outward are formed on the edge 3b, the distribution of suction pressure at the suction port 3a is such that the suction pressure at the

curved portions

4a and 4b is relatively high. . In the suction catheter 10B according to the present embodiment, as shown in FIG. 4A, the bending portion 4a is disposed on the side of the most distal end position 1a (that is, the upper side) with reference to the perpendicular line D. The suction pressure in the region above the perpendicular D at the mouth 3a can be increased. As a result, it is possible to increase the suction pressure in the area on the side of the most distal end position 1a with reference to the perpendicular D, and reduce the suction pressure difference between the area on the side of the most distal end position 1a and the area on the most can do. Therefore, in the suction catheter 10B according to the present embodiment, the thrombus is easily suctioned from the area on the side of the most distal end position 1a in the suction port 3a compared to the conventional suction catheter, and the thrombus caught in the guide wire Suction performance is improved. Furthermore, it is possible to realize the suction catheter 10B in which the blockage of the suction lumen A due to the thrombus is unlikely to occur.

Here, when the shape of the edge 3b forming the suction port 3a is symmetrical with the imaginary line C as the axis of symmetry, even if the

curved portions

4a and 4b are formed on the edge 3b, the suction pressure is generated by the

curved portions

4a and 4b. But not relatively high. The reason is that since the shape of the edge 3 b is symmetrical with respect to the imaginary line C, the suction pressure distribution is not disturbed. In the suction catheter 10B according to the present embodiment, the suction pressure distribution at the suction port 3a is disturbed by making the shape of the edge 3b forming the suction port 3a asymmetric with respect to the virtual line C. . Then, in this way, the edge 3b is shaped to cause disturbance in the suction pressure distribution, and the

curved portions

4a and 4b curved outward are formed on the edge 3b, so that the region above the perpendicular D can be obtained. The suction pressure of the

In the configuration shown in (a) to (e) of FIG. 4, two

curved portions

4a and 4b are formed at the edge 3b. However, the suction catheter 10B according to the present embodiment is not limited to the configuration shown in (a) to (e) of FIG. 4 and may have a curved portion capable of distributing the suction pressure higher in the region above the perpendicular D. The number and arrangement may be sufficient. For example, only the curved portion 4a on the side of the most distal end position 1a with respect to the perpendicular D may be formed on the edge 3b.

Moreover, although the bending part may be provided with two or more, it is preferably two. When two curved portions are provided, it is preferable that there is a positional relationship between the

curved portions

4a and 4b shown in FIG. 4 (a). That is, the curved portion 4b is preferably disposed at a position away from the curved portion 4a, and is particularly preferably disposed on the opposite side of the curved portion 4a with reference to the midpoint O of the imaginary line C.

(Modification)
A modification of the configuration shown in (a) to (e) of FIG. 4 will be described in the configuration of the suction catheter 10B according to the present embodiment. FIG. 5 is a front view showing a schematic configuration as seen from the distal end side of this modified aspiration catheter 10C.

As shown in FIG. 5, the suction catheter 10C differs from the configuration shown in (a) to (e) of FIG. 4 in that the shape of the edge 3b forming the suction port 3a is an elliptical shape. In the suction catheter 10C, the

apexes

4c and 4d in the direction of the long axis E in the ellipse formed by the edge 3b function as the above-described curved portion. The intersection of the major axis E and the minor axis F of the ellipse formed by the edge 3b coincides with the midpoint O of an imaginary line C connecting the most distal end position 1a and the most proximal end position 1b. The elliptical shape formed by the edge 3 b is configured such that the major axis E intersects the imaginary line C, and is asymmetric with the imaginary line C as an axis of symmetry. Then, among the

apexes

4c and 4d, the apex 4c is disposed on the most distal end position 1a side with reference to the perpendicular line D.

By the

apexes

4c and 4d functioning as the above-mentioned curved portion, the suction pressure can be increased in the region closer to the most distal end position 1a than the perpendicular D, as shown in (a) to (e) of FIG. The same effect as the suction catheter 10 is exerted.

In the suction catheter 10A, the major axis / minor axis, which is the ratio of the length (major axis) of the major axis E to the length (minor axis) of the minor axis F in the ellipse formed by the edge 3b, has

apexes

4c and 4d Any ratio may be used as long as it functions as the above-described curved portion. Specifically, the major axis / minor axis is preferably 11/9 to 3/1, and more preferably 3/2 to 2/1.

Further, the inclination angle θ of the major axis E with respect to the virtual line C may be an inclination angle that allows the

vertices

4 c and 4 d to function as the above-described curved portion. Specifically, the inclination angle θ is preferably 5 ° to 85 °, and more preferably 5 ° to 45 °.

The suction catheter 10B according to the present embodiment can be manufactured, for example, by the following manufacturing method. First, the distal end of the aspiration tube material is cut out so that the opening on the distal end side of the aspiration tube material to be the aspiration tube 1 becomes the inclined suction port 3a. Then, suction tube material having suction port 3a and guide wire tube 2 are welded by a conventional method. Thereafter, a cylindrical metal core material having a cross section in the shape of the edge 3b shown in FIG. 4A or 5 is inserted into the suction tube material from the suction port 3a of the welded body. Then, heat processing and cooling are applied below the melting point of the suction tube material. Then, by pulling out the metal core material from the suction tube material, it is possible to obtain the suction catheter 10B provided with the suction tube 1 in which the

curved portions

4a and 4b are formed at the edge 3b of the suction port 3a. For example, when manufacturing the suction catheter 10C shown in FIG. 5, a tubular member having an elliptical cross section is used as the metal core material.

[Summary]
The suction catheter 10 according to an embodiment of the present invention includes a suction tube 1 provided with a suction lumen A having a suction portion 3 at its distal end, and the suction portion 3 is inclined with respect to the axis X of the suction tube 1 A suction catheter 10 having a suction port 3a formed in the suction portion 3. In the suction unit 3, the most distal end position 1a on the most distal end side is set as a first position, and the most proximal end position 1b on the proximal end side. When the second position, the direction of the axis X is the first direction (longitudinal direction), the direction of the line passing through the second position and perpendicular to the axis X is the second direction (vertical direction), The shape of the edge 3b forming the suction port 3a is the same as the third direction (width direction) in a direction perpendicular to both the one direction and the second direction, as viewed from the second position side in the second direction. The first line (virtual line C) connecting the first position and the second position It is a universal configuration.

According to the above configuration, when viewed from the second position (the nearest end position 1b) side in the second direction (vertical direction), the shape of the edge 3b forming the suction port 3a is the first line (virtual line As it is asymmetric with respect to C), disturbance occurs in the suction pressure distribution at the suction port 3a. For this reason, the suction pressure distribution at the suction port 3a is asymmetrical with the first line as a symmetry axis, and the farthest end position with reference to the perpendicular D passing through the middle point O of the first line (virtual line C). The suction pressure difference is reduced between the area on the side of 1a and the area on the side of the nearest end position 1b. Therefore, according to the above configuration, the suction pressure in the area on the first position side can be increased. As a result, according to the above configuration, the thrombus present on the farthest distal end position 1a side is more easily aspirated compared to the conventional aspiration catheter, and the aspiration performance for the thrombus caught by the guide wire is improved.

Further, in the suction catheter 10 according to the embodiment of the present invention, when the two portions of the edge 3b divided on the basis of the first line are the first edge 3c and the second edge 3d, the suction port 3a The shape of the edge 3b forming the edge 3b may be configured such that there is a portion where the first edge 3c and the second edge 3d do not overlap at least in part when viewed from the third direction.

According to the above configuration, when viewed from the second position side in the second direction, the shape of the edge 3b forming the suction port 3a is asymmetrical with respect to the first line. The suction pressure in the area can be increased.

In the suction catheter 10B according to one embodiment of the present invention, the shape of the edge 3b forming the suction port 3a is the proximal end of the suction tube 1 relative to the first line when viewed from the third direction. It is preferable that the shape is curved to the side.

As a result, even if the suction catheter 10B has a small diameter with a small dimension in the vertical direction, it is possible to secure the dimensions of the suction port 3a capable of sucking a thrombus.

Further, in the suction catheter 10 according to the embodiment of the present invention, when the two parts of the edge divided on the basis of the first line are the first edge 3 c and the second edge 3 d, the first edge 3 c It is preferable that the length of the second edge 3d is 3 times or less over 1 time of the length of the second edge 3d.

By setting the dimensions of the first edge 3c and the second edge 3d as in the above configuration, the suction pressure in the area on the first position side in the suction port 3a can be increased.

Further, in the suction catheter 10B according to one embodiment of the present invention, when viewed from the distal end side in the first direction, the shape of the edge 3b forming the suction port 3a is the first line (virtual line C). A configuration in which a curved portion 4a which is asymmetrical as an axis of symmetry and which is curved outward beyond the peripheral edge 3b is disposed at a first position with reference to a perpendicular D passing through the middle point O of the first line. It may be

According to the above configuration, the shape of the edge 3 b forming the suction port 3 a is asymmetrical with the first line as a symmetry axis. Therefore, the suction pressure at the suction port 3a has an asymmetric distribution with the first line as the axis of symmetry. For this reason, in the suction port 3a, a difference in suction pressure occurs between the two areas A1 and A2 divided by the first line (the imaginary line C).

Furthermore, when the curved portion 4a curved outward is formed on the edge 3b, the distribution of suction pressure at the suction port 3a is such that the suction pressure at the curved portion 4a is relatively high. According to the above configuration, the bending portion 4a is disposed on the first position side (that is, the most distal end position 1a side) with reference to the perpendicular D, and hence the bending portion 4a is closer to the first position than the perpendicular D at the suction port 3a. The suction pressure in the area can be increased. As a result, the suction pressure in the area at the first position can be increased with reference to the perpendicular D, and the suction pressure difference between the area at the first position and the area at the second position can be reduced.

In the suction catheter 10B according to an embodiment of the present invention, another curved portion 4b may be further disposed on the opposite side of the curved portion 4a with reference to the midpoint O of the first line.

Even in the above configuration, the thrombus can be more easily aspirated from the region on the most distal end position 1a side of the aspiration port 3a compared to the conventional aspiration catheter.

Further, in the suction catheter 10B according to the embodiment of the present invention, the curved portion 4a is provided across the side wall 1c of the suction lumen A at least in the portion between the first position and the second position. It may be

According to the above configuration, since the curved portion 4a is provided not only to the edge 3b of the suction port 3a but also to the side wall 1c of the suction lumen A, the suction pressure in the area on the first position side can be reliably increased. it can.

Further, in the suction catheter 10C according to one embodiment of the present invention, when viewed from the distal end side in the direction of the axis X, the shape of the edge 3b forming the suction port 3a is an elliptical shape, The configuration may be such that one of the

vertices

4c and 4d in the major axis direction (direction of the major axis E) (apex 4c) is disposed on the first position side with reference to the perpendicular line D.

According to the above configuration, the aspiration pressure in the region on the most distal end position 1a side of the perpendicular D can be increased by the

apexes

4c and 4d functioning as the above-described curved portion.

The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the claims, and embodiments obtained by appropriately combining the technical means disclosed in the different embodiments. Is also included in the technical scope of the present invention.

1 Suction tube 1a most distal end position (first position)
1b closest position (second position)
1c side wall 2 guide wire tube 3 suction part 3a suction port 3b edge 3c first edge 3d

second edge

4a, 4b curved

part

4c,

4d apex

10, 10A, 10B, 10C suction catheter A suction lumen A guide wire lumen C virtual line (Line 1)
D perpendicular X axis line O midpoint

Claims

A suction tube with a suction lumen having a suction at the distal end,
The suction unit is a suction catheter having a suction port formed to be inclined with respect to the axis of the suction tube,
In the suction portion, when the most distal end position is a first position and the most proximal end position is a second position,
The direction of the axis is a first direction, the direction of a line passing the second position and perpendicular to the axis is a second direction, and a direction perpendicular to both the first direction and the second direction is a third. As a direction
Seen from the second position side in the second direction,
A suction catheter characterized in that a shape of an edge forming the suction port is asymmetric with respect to a first line connecting the first position and the second position.
When the two parts of the edge divided on the basis of the first line are the first edge and the second edge,
The shape of the edge forming the suction port is characterized in that there is a portion where the first edge and the second edge do not overlap in at least one portion when viewed from the third direction. Aspiration catheter.
The shape of the edge forming the suction port is a shape that is curved toward the proximal end side of the suction tube than the first line when viewed from the third direction. Aspiration catheter as described.
When the two parts of the edge divided on the basis of the first line are the first edge and the second edge,
The suction catheter according to any one of claims 1 to 3, wherein a length of the first edge is one time or more and three times or less of a length of the second edge.
When viewed from the distal end side of the first direction, the shape of the edge forming the suction port is:
Asymmetrical with the first line as a symmetry axis, and
The curved portion which is curved to the outer side than the peripheral edge is disposed on the first position side with reference to a vertical line passing through the center of the first line. An aspiration catheter as described in Item.
The suction catheter according to claim 5, wherein another curved portion is further disposed opposite to the curved portion with respect to the center of the first line.
The suction catheter according to claim 5 or 6, wherein the curved portion is provided across the side wall of the suction lumen at least in a portion between the first position and the second position.
Viewed from the distal end in the direction of the axis,
The shape of the edge forming the suction port is an elliptical shape, and any one of the vertices in the major axis direction of the ellipse is disposed on the first position side with respect to the perpendicular. The suction catheter according to any one of 5 to 7.