Catheter
The catheter's innovative design with aligned tubes and radial openings facilitates guide wire insertion into vascular branches, addressing rotation and maneuverability issues in uneven rigidity catheters.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- ASAHI INTECC CO LTD
- Filing Date
- 2025-11-11
- Publication Date
- 2026-05-21
AI Technical Summary
Existing catheters with uneven rigidity distribution in their cross-sections face difficulties in rotating and inserting guide wires into desired blood vessel branches, particularly when navigating complex vascular structures.
A catheter design featuring a first and second tube with radially outward openings and specific positional alignment of these tubes' wall portions, allowing for easy guide wire insertion into vascular branches by guiding the wire through inclined openings and controlled bending directions.
Enables easy and precise guidance of guide wires into desired vascular branches, enhancing the catheter's maneuverability and insertion capabilities in complex vascular environments.
Smart Images
Figure JP2025039462_21052026_PF_FP_ABST
Abstract
Description
Catheter
[0004]
[0001] The present disclosure relates to a catheter.
[0002] A catheter is known as a medical device for removing an occlusion that closes a blood vessel, such as a chronic total occlusion (CTO), and improving blood flow. In order to deal with occlusions not only in the main blood vessel but also in blood vessel branches, catheters having multiple lumens may be used.
[0003] For example, Patent Document 1 discloses a technique related to a multi-lumen catheter.
[0004] Japanese Patent Application Laid-Open No. 2024-37226
[0005] Depending on the structure of the catheter, the rigidity distribution in the cross-section of the catheter may be uneven. When the rigidity distribution is uneven like this, it may be impossible to easily rotate the catheter within the blood vessel. For example, in a multi-lumen catheter, it may be difficult to rotate. Further, in another example, there is a catheter that has a reinforcing body and has a directionality in terms of ease of bending. When such a catheter is inserted into a blood vessel, after being in a state following the shape of the blood vessel, it is difficult to rotate the catheter in a desired direction.
[0006] When it is thus impossible to easily rotate the catheter, it becomes difficult to insert a guide wire from the lumen of the catheter into a desired blood vessel branch.
[0007] The present disclosure has been made based on the above circumstances, and provides a technique that can easily insert a guide wire into a desired blood vessel branch.
[0008] A catheter relating to one viewpoint comprises a first tube having a first lumen and a second tube having a second lumen, wherein the tip side of the second tube has an opening that opens radially outward from the second tube, and in a cross-section of the catheter, the position where the first wall portion forming the opening is projected onto the alignment line connecting the centers of the first tube and the second tube is a first position, and the position where the second wall portion forming the opening is projected onto the alignment line is a second position different from the first position.
[0009] Figure 1 is a schematic side view of a catheter according to one embodiment. Figure 2 is a cross-sectional view of the catheter according to one embodiment along the line A-A in Figure 1. Figure 3 is a schematic perspective view of a portion of the tip side of the catheter according to one embodiment. Figure 4 is a cross-sectional view of the catheter according to one embodiment along the line C-C in Figure 3. Figure 5 is a cross-sectional view of the catheter according to one embodiment along the line B-B in Figure 1. Figure 6 is a partial cross-sectional view of the cross-section of the catheter according to the first modified example. Figure 7 is a partial cross-sectional view of the cross-section of the catheter according to the second modified example. Figure 8 is a partial cross-sectional view of the cross-section of the catheter according to the third modified example. Figure 9 is a first cross-sectional view of the cross-section of the catheter according to the fourth modified example. Figure 10 is a second cross-sectional view of the cross-section of the catheter according to the fourth modified example.
[0010] Catheters according to the embodiments will be described with reference to the drawings. This disclosure is not limited to the embodiments shown in each drawing. The catheters shown in each drawing are shown with example dimensions to facilitate understanding of the implementation, and the actual dimensions are not limited thereto.
[0011] In this specification, “tip side” and “tip direction” mean the side and direction along the longitudinal direction of the catheter, i.e., the axial direction, where the tip is located relative to the shaft. “Proximal side” and “proximal direction” mean the side and direction along the longitudinal direction of the catheter, opposite to the tip side and in that direction.
[0012] Figure 1 is a schematic side view of a catheter according to one embodiment.
[0013] Catheter 1 is a long medical device that is inserted into the lumen of a living body, such as a blood vessel, and used for diagnosis and treatment. Catheter 1 has a shaft 20, a tip 30, and a connector 10.
[0014] The shaft 20 is a long, tubular member. The shaft 20 has a first tube 40 having a first lumen 41 extending in the longitudinal direction (X-axis direction), a second tube 50 having a second lumen 51 extending in the longitudinal direction (X-axis direction), and a core wire 60. The first lumen 41 is a lumen for the guide wire. The second lumen 51 is a lumen for the guide wire.
[0015] The connector 10 is a component used by the operator to grasp the catheter 1. The connector 10 is connected to the proximal end of the shaft 20. The connector 10 has a through hole 11 that extends in the longitudinal direction of the catheter 1. The through hole 11 communicates with the second lumen 51 of the second tube 50.
[0016] The tip 30 is a hollow component and is connected to the end of the shaft 20. The tip 30 is connected to the shaft 20 such that the lumen of the tip 30 communicates with the first lumen 41 of the first tube 40 of the shaft 20. The tip 30 has a pointed shape that is pointed toward the tip to facilitate passage through blood vessels.
[0017] The material of the tip 30 may be flexible, as the catheter 1 will advance through a blood vessel. Such flexible materials may be, for example, resin materials such as polyurethane or polyurethane elastomer. These resin materials may be mixed with powders of materials that are difficult for X-rays to penetrate, such as tungsten, gold, or platinum. The tip 30 may have a marker formed from a material that is difficult for X-rays to penetrate.
[0018] The first tube 40 is a long, hollow member. The tip of the first tube 40 is connected to the tip 30. The base end of the first tube 40 extends to the middle of the shaft 20. The tip side of the first lumen 41 communicates with the lumen of the tip 30. The base end of the first lumen 41 is open to the outside of the catheter 1. Therefore, the first lumen 41 is a rapid exchange type lumen formed in the range from the tip to the middle of the shaft 20.
[0019] The second tube 50 is a long, hollow member. The tip of the second tube 50 is positioned closer to the base end than the tip of the first tube 40. An opening 52 is formed at the tip end of the second tube 50, opening radially outward. The base end of the second tube 50 is connected to the connector 10. The tip end of the second lumen 51 is open radially outward from the second tube 50. The base end of the second lumen 51 communicates with the through hole 11 of the connector 10. Therefore, the second lumen 51 is an over-the-wire type lumen formed in the range from approximately the tip to the base end of the shaft 20.
[0020] Figure 2 is a cross-sectional view of a catheter according to one embodiment, taken along the line A-A in Figure 1.
[0021] The shaft 20 of catheter 1 includes a first tube 40, a second tube 50, a core wire 60 as an example of a rigid part, and an outer layer 21.
[0022] The first tube 40 and the second tube 50 are arranged so as to be aligned in the Z-axis direction. The inner and outer diameters of the first tube 40 and the second tube 50 are approximately the same.
[0023] The first tube 40 has a layer of resin material such as polyimide, polyamide, polyamide elastomer, polyolefin, polyester, polyester elastomer, nylon, or polytetrafluoroethylene. The first tube 40 may also contain a coil in which strands of metal material such as stainless steel or Ni-Ti alloy are wound in a spiral shape.
[0024] The second tube 50 has a layer of resin material such as polyimide, polyamide, polyamide elastomer, polyolefin, polyester, polyester elastomer, nylon, or polytetrafluoroethylene. The second tube 50 may also contain a coil in which strands of metal material such as stainless steel or Ni-Ti alloy are wound in a spiral shape.
[0025] The outer layer 21 is a layer that connects the first tube 40 and the second tube 50 by covering at least a portion of the outer surface of the first tube 40 and the second tube 50. The material of the outer layer 21 may be a resin material such as polyimide, polyamide, polyamide elastomer, polyolefin, polyester, polyester elastomer, nylon, or polytetrafluoroethylene.
[0026] The core wire 60 is positioned within the outer layer 21 in the negative Y-axis direction at the same Z-axis position as the midpoint of the Z-axis direction between the first tube 40 and the second tube 50. The core wire 60 may be made of a metallic material such as stainless steel, Ni-Ti alloy, or cobalt-chromium alloy.
[0027] In the portion shown in Figure 2, the catheter 1 is easily bent in the positive direction of the Y-axis (referred to as the easily bendable direction) due to the arrangement of the core wire 60, etc.
[0028] Figure 3 is a schematic perspective view of a portion of the tip side of a catheter according to one embodiment. Figure 4 is a cross-sectional view of the catheter according to one embodiment along the line C-C in Figure 3.
[0029] The second tube 50 has an opening 52 at its tip that is open in the positive direction of the Y-axis. An inclined portion 53 is formed at the tip of the opening of the second tube 50. As shown in Figures 3 and 4, the inclined portion 53 is formed to guide the inner surface of the second tube 50 on the negative side of the Y-axis in the direction of the opening 52, in this example, in the positive direction of the Y-axis. Therefore, by inserting the guidewire from the proximal end to the tip of the second lumen 51, the guidewire is guided by the inclined portion 53 and advanced in the direction of the opening 52. This makes it possible to easily and appropriately insert the guidewire into the vascular side branch located in the direction of the opening.
[0030] A shaping section 61 is provided at the tip end of the second tube 50. The shaping section 61 is a layer that connects the tip of the second tube 50 to the side surface of the first tube 40 to create a smooth curved surface. The material of the shaping section 61 may be a resin material such as polyimide, polyamide, polyamide elastomer, polyolefin, polyester, polyester elastomer, nylon, or polytetrafluoroethylene.
[0031] Figure 5 is a cross-sectional view of a catheter according to one embodiment, taken along the line B-B in Figure 1.
[0032] The shaft 20 of catheter 1 includes a first tube 40, a second tube 50, a core wire 60, and an outer layer 21.
[0033] The first tube 40 and the second tube 50 are arranged so as to be aligned in the Z-axis direction. That is, the first tube 40 and the second tube 50 are arranged along the alignment line D.
[0034] The outer layer 21 is provided in such a way that it does not block the opening of the second tube 50 in the cross-section along the B-B line.
[0035] In a cross-section along the B-B line, the core wire 60 is positioned within the outer layer 21 in the negative Y-axis direction at the midpoint of the Z-axis direction between the first tube 40 and the second tube 50.
[0036] The second tube 50 has an opening 52 whose opening direction E is in a direction that intersects the alignment line D, which in this example is a 90-degree direction. The opening direction is the direction outward along a line perpendicular to the line connecting an arbitrary point on the first wall portion 50a that forms the opening 52 of the second tube 50 in the cross-section with an arbitrary point on the second wall portion 50b (the direction from the center of the second tube 50 through the opening 52 toward the outside of the second tube 50). In this example, the first wall portion 50a is the surface of the second tube 50 facing the positive Y-axis direction of the Z-axis, and the second wall portion 50b is the surface of the second tube 50 facing the negative Y-axis direction of the Z-axis. Any point on the first wall portion 50a may be, for example, a point on the inner circumference of the second tube 50, and any point on the second wall portion 50b may be, for example, a point on the inner circumference of the second tube 50. In this example, the opening direction E is directed toward the second side opposite to the first side where the core wire 60 is located relative to the alignment line D. The opening direction is a direction that intersects the alignment line D, and it is sufficient if the guide wire delivered from the opening 52 does not interfere with other parts of the catheter 1. For example, the angle between the opening direction and the alignment line D may be between 45 degrees and 90 degrees. In the cross-section of the catheter 1, the position obtained by projecting the first wall portion 50a onto the alignment line D connecting the centers of the first tube 40 and the second tube 50 is the first position, and the position obtained by projecting the second wall portion 50b onto the alignment line D is a second position different from the first position.
[0037] In the cross-section along line B-B, the second tube 50 is partially annular, and the central angle of the second tube 50 is 180 degrees. In this embodiment, the central angle of the second tube 50 is less than 180 degrees towards the tip of line B-B.
[0038] In catheter 1, the direction in which the core wire 60's center 60o and the catheter 1's center 1o are connected is the direction of easy bending G. In catheter 1, the direction of easy bending G is the direction of the short axis in the cross-section of catheter 1. In this example, the angle between the opening direction E of the opening 52 and the direction of easy bending G is 0 degrees. The angle between the opening direction E of the opening 52 and the direction of easy bending G may be 0 degrees or more and less than 90 degrees, or greater than 90 degrees and 180 degrees or less.
[0039] According to the catheter according to this embodiment, it is possible to easily guide the guide wire to the vascular side branch located on the side in the direction where the catheter is easily bent. For example, it is possible to easily guide the guide wire to the vascular side branch on the bent side of the bent blood vessel.
[0040] The catheter according to the first modification will be described.
[0041] FIG. 6 is a partial cross-sectional view of the catheter according to the first modification in the cross-section. FIG. 6 is a partial cross-sectional view of the catheter according to the first modification in the cross-section corresponding to the line B-B in FIG. 1.
[0042] The catheter according to the first modification includes a second tube 70 instead of the second tube 50.
[0043] The second tube 70 has an opening 72 that opens in an opening direction E1 in which the angle θ formed in the counterclockwise direction with the arrangement line D is 45 degrees.
[0044] According to the catheter according to the first modification, it becomes possible to easily guide the guide wire to the vascular side branch located in the direction that forms a 45-degree angle with the arrangement line D in the counterclockwise direction.
[0045] The catheter according to the second modification will be described.
[0046] FIG. 7 is a partial cross-sectional view of the catheter according to the second modification in the cross-section. FIG. 7 is a partial cross-sectional view of the catheter according to the second modification in the cross-section corresponding to the line B-B in FIG. 1.
[0047] The catheter according to the second modification includes a second tube 80 instead of the second tube 50.
[0048] The second tube 80 has an opening 82 that opens in an opening direction E2 in which the angle θ formed in the clockwise direction with the arrangement line D is 90 degrees.
[0049] According to the catheter of the second modification, the guidewire can be easily guided to a vascular side branch located at a 90-degree angle clockwise from the placement line D. For example, the guidewire can be easily guided to a vascular side branch on the opposite side of the bend in a bent blood vessel.
[0050] A catheter relating to the third modified example will be described.
[0051] Figure 8 is a partial cross-sectional view of the catheter according to the third modified example. Figure 8 is a partial cross-sectional view of the catheter according to the third modified example, corresponding to the line B-B in Figure 1.
[0052] The catheter according to the third modified example is equipped with a second tube 90 instead of the second tube 50.
[0053] The second tube 90 has an opening 92 that opens in the opening direction E3, where the clockwise angle θ with respect to the alignment line D is 45 degrees.
[0054] According to the third modified catheter, the guidewire can be easily guided to the vascular side branch located at a 45-degree angle clockwise to the placement line D.
[0055] The catheter relating to the fourth modified example will be described.
[0056] Figure 9 is a first cross-sectional view of the catheter according to the fourth modified example. Figure 9 is a cross-sectional view of the catheter according to the fourth modified example, corresponding to the line A-A in Figure 1. Figure 10 is a second cross-sectional view of the catheter according to the fourth modified example. Figure 10 is a cross-sectional view of the catheter according to the fourth modified example, corresponding to the line B-B in Figure 1.
[0057] The catheter 1A according to the fourth modified example has a shaft 120 instead of the shaft 20 of the catheter 1 shown in Figure 1. The shaft 120 includes four lumens 141, 151, 161, and 171, and comprises a first tube 140, a second tube 150, a third tube 160, a fourth tube 170, and an outer layer 121.
[0058] The first tube 140 is the same as the first tube 40 of catheter 1. The second tube 150 is the same as the second tube 50 of catheter 1.
[0059] The first tube 140 and the second tube 150 are arranged in the Z-axis direction. The third tube 160 and the fourth tube 170 are arranged side by side in the Y-axis direction. The inner and outer diameters of the first tube 140 and the second tube 150 are approximately the same. The inner and outer diameters of the third tube 160 and the fourth tube 170 are approximately the same. The inner and outer diameters of the first tube 140 and the second tube 150 are longer than the inner and outer diameters of the third tube 160 and the fourth tube 170.
[0060] The outer layer 121 is a layer that connects the first tube 140, the second tube 150, the third tube 160, and the fourth tube 170 by covering at least a portion of their outer surfaces. In the cross-section corresponding to line B-B in Figure 1, the outer layer 121 is provided so as not to block the opening of the second tube 150. The material of the outer layer 121 may be a resin material such as polyimide, polyamide, polyamide elastomer, polyolefin, polyester, polyester elastomer, nylon, or polytetrafluoroethylene.
[0061] The third tube 160 has a layer of resin material such as polyimide, polyamide, polyamide elastomer, polyolefin, polyester, polyester elastomer, nylon, or polytetrafluoroethylene.
[0062] The fourth tube 170 has a layer of resin material such as polyimide, polyamide, polyamide elastomer, polyolefin, polyester, polyester elastomer, nylon, or polytetrafluoroethylene.
[0063] A pair of control wires (not shown) for controlling the bending of the catheter 1A are inserted through the third tube 160 and the fourth tube 170. The tip ends of the pair of control wires are connected to the tip of the catheter 1A. When the proximal end of one of the pair of control wires is pulled, the tip of the catheter 1A bends. In this embodiment, when the control wire on the third tube 160 side is pulled, the catheter 1A bends in the positive direction of the Y-axis, and when the control wire on the fourth tube 170 side is pulled, the catheter 1A bends in the negative direction of the Y-axis.
[0064] The second tube 150 has an opening 152 whose opening direction E4 is in a direction intersecting the alignment line D, which in this example is a direction forming a 90-degree angle. The opening direction is the direction outward along a line perpendicular to the line connecting an arbitrary point on the first wall portion 150a that forms the opening 152 of the second tube 150 in the cross-section with an arbitrary point on the second wall portion 150b (the direction from the center of the second tube 150 through the opening 152 toward the outside of the second tube 150). In this example, the first wall portion 150a is the surface of the second tube 50 facing the positive Y-axis direction of the Z-axis, and the second wall portion 150b is the surface of the second tube 50 facing the negative Y-axis direction of the Z-axis. Any point on the first wall portion 150a may be, for example, a point on the inner circumference side of the second tube 150, and any point on the second wall portion 150b may be, for example, a point on the inner circumference side of the second tube 150. The opening direction is one that intersects the alignment line D, and is such that the guidewire delivered from the opening 152 does not interfere with other parts of the catheter 1A. For example, the angle between the opening direction E4 and the alignment line D may be between 45 degrees and 90 degrees. In the cross-section of the catheter 1A, the position where the first wall portion 150a is projected onto the alignment line D connecting the centers of the first tube 140 and the second tube 150 is the first position, and the position where the second wall portion 50b is projected onto the alignment line D is a second position different from the first position.
[0065] In the cross-section of the portion corresponding to line B-B, the second tube 150 is partially annular, and the central angle of the second tube 150 is 180 degrees. In this embodiment, the central angle of the second tube 150 is less than 180 degrees towards the tip of the portion corresponding to line B-B.
[0066] Catheter 1A has a bending direction G1 in which the direction connecting the third tube 160 and the fourth tube 170 is easily bent. In catheter 1A, the bending direction G1 is in the direction of the short axis in the cross-section of catheter 1A. In this example, the angle between the opening direction E4 of the opening 152 and the bending direction G1 is 0 degrees. The angle between the opening direction E4 of the opening 152 and the bending direction G1 may be 0 degrees or more and less than 90 degrees, or greater than 90 degrees and 180 degrees or less.
[0067] The technologies disclosed herein are not limited to the embodiments and modifications described above, and can be modified in various forms without departing from their essence, for example, the following modifications are possible.
[0068] In the embodiments and modifications described above, the catheter does not need to be equipped with a core wire.
[0069] In the embodiments and modifications described above, the catheter may have only one lumen, or it may have three or five or more lumens.
[0070] This disclosure is not limited to the embodiments described above, and all modifications within the meaning and scope of the claims are intended to be included.
Claims
1. A catheter (1) comprising a first tube (40) having a first lumen (41) and a second tube (50) having a second lumen (51), wherein the tip end of the second tube (50) has an opening (52) that opens radially outward from the second tube (50), and in a cross-section of the catheter (1), the position of the first wall portion (50a) forming the opening (52) projected onto the alignment line (D) connecting the centers of the first tube (40) and the second tube (50) is a first position, and the position of the second wall portion (50b) forming the opening (52) projected onto the alignment line (D) is a second position different from the first position.
2. The catheter (1) according to claim 1, wherein the angle between a line (E, E1, E2, E3) perpendicular to the line connecting an arbitrary point on the first wall portion (50a) and an arbitrary point on the second wall portion (50b), and the arrangement line (D), is 45 degrees or more and 90 degrees or less.
3. The catheter (1) according to claim 2, wherein the angle between the vertical line (E, E2) and the alignment line (D) is 90 degrees.
4. A catheter (1) according to any one of claims 1 to 3, having a rigid portion (60) extending from the proximal end to the distal end and positioned on the first side with respect to the arrangement line (D), wherein the opening direction (E, E1), which is the direction in which a line (E, E1) perpendicular to the line connecting the first wall portion (50a) and the second wall portion (50b) is directed, and which is the direction from the center of the second tube (50) through the opening (52) toward the outside of the second tube (50), is directed toward the second side opposite to the first side with respect to the arrangement line (D).
5. The catheter (1) according to any one of claims 1 to 4, wherein the second tube (50) has a sloping portion (53) at its tip that guides the inner surface of the second tube (50) toward the opening side of the opening (52).
6. The catheter (1) according to any one of claims 1 to 5, wherein in a cross-section of the portion of the second tube (50) where the opening (52) is located, the second tube (50) is partially annular, and the minimum central angle of the second tube (50) is 180 degrees or less.
7. The catheter (1) according to any one of claims 1 to 6, wherein the tip of the second tube (50) is located more proximal than the tip of the first tube (40).
8. A catheter (1, 1A) comprising one or more tubes (50, 150), having a direction of easy bending (G, G1) which is a direction in which it is easily bent, the tubes (50, 150) each having an opening (52, 152) at the tip end that opens radially outward from the tubes (50, 150), and in a cross-section of the catheter (1, 1A), the angle (θ) between a line (E1, E2, E3, E4) perpendicular to the line connecting an arbitrary point on the first wall portion (50a, 150a) forming the opening (52, 152) and an arbitrary point on the second wall portion (50b, 150b) forming the opening (52, 152), and the direction of easy bending (G, G1), is either 0 degrees or more and less than 90 degrees, or greater than 90 degrees and less than or equal to 180 degrees.
9. The catheter (1) according to claim 8, having a rigid portion (60) positioned from the proximal end to the distal end.
10. The catheter (1) according to claim 9, wherein the direction of easy bending (G) is the direction from the center (60o) of the rigid portion (60) toward the center of the catheter (1o) in the cross-section of the catheter.
11. The catheter (1, 1A) according to any one of claims 8 to 10, wherein the angle between the vertical line (E1, E2, E3, E4) and the direction of easy bending (G, G1) is either 0 degrees or more and 45 degrees or 135 degrees or more and 180 degrees or less.
12. The catheter (1, 1A) according to any one of claims 8 to 11, wherein the tube (50, 150) has a sloping portion (53) at its tip that guides the inner surface of the tube (50, 150) in the direction toward the opening (52, 152).
13. The catheter (1, 1A) according to any one of claims 8 to 12, wherein in a cross-section of the portion of the catheter (1, 1A) where the opening (52, 152) is located, the tube (50, 150) is partially annular, and the minimum central angle of the tube (50, 150) is 180 degrees or less.