Catheter assembly

Abstract

To enable easy and proper removal of trapped catheters. [Solution] The catheter assembly 1 comprises a long catheter 10 and a long auxiliary device 20 separate from the catheter 10. The catheter 10 has a magnetic body 14 located at a position a distance L1 from its tip toward the proximal end, and the auxiliary device 20 has a magnetic body 22 located at a second distance shorter than the first distance from its tip, which can be attracted to the magnetic body 14 by magnetic force.

Description

Technical Field

[0001] The present disclosure relates to a catheter assembly.

Background Art

[0002] Patent Document 1 discloses a catheter having an anti-adhesion film that can be sheared and removed at its tip. With this catheter, the anti-adhesion film to which the embolic agent has adhered can be broken, and the catheter tube can be pulled out.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the catheter of Patent Document 1, the anti-adhesion film remains in the blood vessel, so there is a risk of sequelae and the like.

[0005] The present disclosure has been made based on the above circumstances, and provides a technique capable of easily and appropriately removing a trapped catheter.

Means for Solving the Problems

[0006] A catheter assembly according to one aspect of the present disclosure includes a long catheter and a long auxiliary device separate from the catheter. The catheter has a first magnetic body at a position separated from its tip by a first distance toward the proximal end side. The auxiliary device has a second magnetic body at a position separated from its tip by a second distance shorter than the first distance, and the second magnetic body can be attracted by the first magnetic body with a magnetic force.

Brief Description of the Drawings

[0007] [Figure 1]Figure 1 is an overall view of a catheter assembly according to one embodiment. [Figure 2] Figure 2 is a first diagram illustrating a method of using a catheter assembly according to one embodiment. [Figure 3] Figure 3 is a second diagram illustrating a method of using a catheter assembly according to one embodiment. [Figure 4] Figure 4 is a third diagram illustrating a method of using a catheter assembly according to one embodiment. [Figure 5] Figure 5 is a fourth diagram illustrating a method of using a catheter assembly according to one embodiment. [Figure 6] Figure 6 illustrates another method of using the catheter assembly according to one embodiment. [Figure 7] Figure 7 is a diagram showing the configuration of a modified catheter. [Figure 8] Figure 8 is a diagram showing the configuration of an auxiliary device related to a modified example. [Modes for carrying out the invention]

[0008] Catheter assemblies according to embodiments will be described with reference to the drawings. This disclosure is not limited to the embodiments shown in the drawings. The catheter assemblies and parts thereof shown in each drawing are shown with example dimensions for ease of understanding, and the actual dimensions are not limited thereto. In this specification, “tip side” and “tip direction” mean the side and direction of the catheter assembly that is inserted into the patient’s body. “Proximal side” and “proximal direction” mean the side and direction opposite to “tip side” and “tip direction.” “Tip” refers to the tip end of any component or part, and “proximal end” refers to the proximal end of any component or part.

[0009] Figure 1 is an overall view of a catheter assembly according to one embodiment.

[0010] The catheter assembly 1 includes a guiding catheter 2, a catheter 10 for injecting liquid embolic material, and an auxiliary device 20 for removing the catheter 10 if it becomes trapped.

[0011] The guiding catheter 2 is a catheter that assists in inserting the catheter 10 and auxiliary device 20 to a site close to the area in the body to be embolized (referred to as the embolization target area). The guiding catheter 2 has a hollow shaft 3 and a connector 4.

[0012] The hollow shaft 3 has a lumen into which a catheter 10 or auxiliary device 20 can be inserted. Since the hollow shaft 3 is inserted into a blood vessel, it may have antithrombotic, flexible, and biocompatible properties. The material of the hollow shaft 3 may be, for example, polyamide resin, polyolefin resin, polyester resin, polyurethane resin, silicone resin, fluororesin, etc., or it may be metal such as hypotube.

[0013] The connector 4 is a component used by the operator to grasp the guiding catheter 2. The connector 4 is connected to the proximal end of the hollow shaft 3. The connector 4 has a through hole 5 that communicates with the lumen of the hollow shaft 3, allowing the catheter 10 or auxiliary device 20 to be inserted into the lumen of the hollow shaft 3 from the outside, and an opening 6 formed at the proximal end of the through hole 5. The form of the connector 4 is not particularly limited and can be any shape as long as it is easy for the operator to grasp.

[0014] The catheter 10 has a lumen 10a for allowing liquid embolic material to flow from the proximal end to the distal end. The catheter 10 has a long shaft 11, a tip 12, and a marker 13.

[0015] The tip 12 is the tip portion of the catheter 10. The tip 12 is flexible because the catheter 10 moves through blood vessels. The material of the tip 12 may be, for example, a resin such as polyurethane or polyurethane elastomer.

[0016] The marker 13 is disposed between the proximal end side of the tip chip 12 and the distal end side of the shaft 11. The marker 13 has radiopacity in order to enable grasping of the position of the distal end of the catheter 10 under fluoroscopy. The marker 13 may be formed by mixing a radiopaque material such as bismuth trioxide, tungsten, or barium sulfate into, for example, a polyamide resin, a polyolefin resin, a polyester resin, a polyurethane resin, a silicone resin, or a fluororesin, or may be formed of a radiopaque material such as gold, platinum, tungsten, or an alloy containing these elements.

[0017] The shaft 11 is hollow. The shaft 11 has, for example, a layer of a resin material such as polyimide, polyamide, polyamide elastomer, polyolefin, polyester, polyester elastomer, nylon, or polytetrafluoroethylene. The shaft 11 may have a braid (also referred to as a blade) in which a plurality of metal wires are woven in a mesh pattern for reinforcement.

[0018] The shaft 11 has a magnetic body 14 (corresponding to the first magnetic body). The magnetic body 14 can be attracted by the magnetic body 22 described later by magnetic force. In the present embodiment, the magnetic body 14 is provided at a position at a distance L1 (corresponding to the first distance) from the distal end of the tip chip 12 and at a position at a distance L2 from the proximal end side of the marker 13. The length of the magnetic body 14 in the longitudinal direction of the catheter 10 is L3. The magnetic body 14 may have radiopacity in order to enable grasping of the position under fluoroscopy.

[0019] The auxiliary device 20 is a member separate from the catheter 10. The auxiliary device 20 has a shaft 21 and a magnetic body 22 (corresponding to the second magnetic body). The auxiliary device 20 has the magnetic body 22 at a position at a distance shorter than the distance L1 from its distal end (corresponding to the second distance). In the present embodiment, the magnetic body 22 is provided, for example, at the most distal end position of the auxiliary device 20, that is, at a position where the second distance is 0.

[0020] The shaft 21 is an elongated member. The shaft 21 has an outer diameter smaller than, for example, the diameter of the lumen 10a of the catheter 10. The strength of the shaft 21 against tension may be higher than the strength of the shaft 11 against tension.

[0021] The magnetic body 22 can be attracted to the magnetic body 14 of the catheter 10 by magnetic force. The magnetic bodies 14 and 22 may be permanent magnets. One of the magnetic bodies 14 and 22 may be a permanent magnet, and the other may be a metal or alloy attracted to the magnet. The length L4 in the longitudinal direction of the magnetic body 22 may be the same as the length L3 in the longitudinal direction of the magnetic body 14, or may be longer than the length L3. The magnetic body 22 may have radiation impermeability in order to enable its position to be grasped under fluoroscopy. The force required to separate the magnetic body 14 and the magnetic body 22 in the longitudinal direction of the catheter 10 when they are stuck together can be changed depending on the material of the magnetic body 14 or the magnetic body 22, etc. The force required to separate the magnetic body 14 and the magnetic body 22 in the longitudinal direction of the catheter 10 when they are stuck together may be, for example, a force of a magnitude that does not break the shaft 11.

[0022] A method of using the catheter assembly 1 will be described.

[0023] FIG. 2 is a first diagram for explaining a method of using the catheter assembly according to an embodiment. FIG. 3 is a second diagram for explaining a method of using the catheter assembly according to an embodiment. FIG. 4 is a third diagram for explaining a method of using the catheter assembly according to an embodiment. FIG. 5 is a fourth diagram for explaining a method of using the catheter assembly according to an embodiment.

[0024] The operator, such as a physician, inserts the tip of the guiding catheter 2 into the blood vessel. Next, the operator advances the guiding catheter 2 along the blood vessel until the tip reaches a predetermined location within the blood vessel. The operator may also advance a predetermined guidewire to a predetermined location beforehand and then advance the guiding catheter 2 along the guidewire to the predetermined location.

[0025] Next, the operator inserts the tip of catheter 10 through the proximal opening 6 of guiding catheter 2 and advances catheter 10 within guiding catheter 2. Then, as shown in Figure 2, the operator advances catheter 10 until its tip reaches the embolization target area T. The position of the tip of catheter 10 can be determined by observing the marker 13 under fluoroscopy.

[0026] Next, the operator injects the liquid embolic material from the tip of the catheter 10 toward the embolic area T by supplying the liquid embolic material through the lumen 10a of the catheter 10.

[0027] Thus, when the liquid embolic material is injected, it hardens in the embolic area T and emboluses the blood vessel. In such cases, as shown in Figure 3, the liquid embolic material may flow upstream, i.e., towards the catheter 10, and harden in the area shown as the actual embolic area B, surrounding the tip of the catheter 10, and the area near the tip of the catheter 10 may become trapped.

[0028] In such cases, even if the operator attempts to remove the catheter 10 by pulling its proximal end after the injection of the liquid embolic material is complete, the catheter 10 cannot be removed because it is trapped by the hardened liquid embolic material (simply referred to as the embolic material). Applying excessive tension to the catheter 10 at this time carries the risk of vascular damage or rupture of the catheter 10.

[0029] Therefore, in this embodiment, the operator removes the catheter 10 using the auxiliary device 20 as follows.

[0030] Specifically, the operator inserts the auxiliary device 20 through the proximal opening 6 of the guiding catheter 2 and advances the auxiliary device 20 within the guiding catheter 2. Next, as shown in Figure 3, the operator advances the auxiliary device 20 so that its tip approaches the tip of the catheter 10. The position of the tip of the auxiliary device 20 can be determined by observing the magnetic material 22 under fluoroscopy.

[0031] As the operator pushes the auxiliary device 20 further, the magnetic material 22 is attracted to and fixed to the magnetic material 14 by the magnetic force generated between them, as shown in Figure 4.

[0032] Next, the operator pulls the auxiliary device 20 towards the proximal end in the state shown in Figure 4. In addition to the auxiliary device 20, the catheter 10 may also be pulled towards the proximal end. When the auxiliary device 20 is pulled towards the proximal end, a tensile force towards the proximal end is applied to the magnetic material 14 of the catheter 10 via the magnetic material 22 of the auxiliary device 20. In this way, a tensile force towards the proximal end can be applied to the magnetic material 14 near the tip of the catheter 10, so that the tensile force can be effectively applied to the tip portion of the catheter 10 that is trapped in the embolic material. This prevents excessive tensile force from being generated on the portion of the shaft 11 that is more proximal than the magnetic material 14, and reduces the risk of catheter 10 rupture.

[0033] As a result, the catheter 10 can be detached from the embolic material, as shown in Figure 5, and the catheter 10 can be properly removed from the patient's body.

[0034] Next, we will describe another way to use catheter assembly 1.

[0035] Figure 6 illustrates another method of use of the catheter assembly according to one embodiment. Figure 6 shows the auxiliary device 20 inserted into the lumen 10a of the catheter 10.

[0036] In this method, if the tip of the catheter 10 becomes trapped, the operator inserts the tip of the auxiliary device 20 into the lumen 10a from the proximal end of the catheter 10 and pushes the auxiliary device 20 forward into the lumen 10a towards the tip, i.e., to the right in the diagram, as shown in Figure 6.

[0037] In this way, when the auxiliary device 20 is pushed toward the tip, the magnetic material 22 is joined to the magnetic material 14. Therefore, the operator can easily push the auxiliary device 20 to the position where the magnetic material 22 is joined to the magnetic material 14.

[0038] Next, the operator pulls the auxiliary device 20 towards the proximal end. The operator may also pull the catheter 10 towards the proximal end in addition to the auxiliary device 20. When the auxiliary device 20 is pulled towards the proximal end, a tensile force towards the proximal end is applied to the magnetic material 14 of the catheter 10 via the magnetic material 22 of the auxiliary device 20. In this way, a tensile force towards the proximal end can be applied to the magnetic material 14 near the tip of the catheter 10, so that the tensile force can be effectively applied to the tip portion of the catheter 10 that is trapped in the embolic material. This prevents excessive tensile force from being generated on the portion of the shaft 11 that is more proximal than the magnetic material 14, and reduces the risk of catheter 10 rupture.

[0039] Next, we will explain variations of the catheter.

[0040] Figure 7 is a diagram of the catheter configuration according to a modified example. Parts similar to those in catheter 10 in Figure 1 are denoted by the same reference numerals.

[0041] Catheter 10A is a catheter equipped with multiple magnetic materials 14, 15 that can be attracted to a magnetic material 22 by magnetic force.

[0042] The magnetic material 15 (corresponding to the third magnetic material) is located at a position closer to the proximal end than the magnetic material 14. The magnetic material 15 may be radiopaque in order to allow its position to be determined under radiofluoroscopy.

[0043] With this catheter 10A, even if the magnetic material 22 of the auxiliary device 20 cannot reach a position where it can connect with the magnetic material 14 due to the influence of embolic material or the like, the magnetic material 22 can be connected to the magnetic material 15. Therefore, in such cases, the operator can properly withdraw the catheter 10 by pulling the auxiliary device 20 towards the proximal end.

[0044] Next, we will describe some variations of the auxiliary device.

[0045] Figure 8 is a diagram showing the configuration of an auxiliary device according to a modified example. Parts similar to those in the auxiliary device 20 in Figure 1 are denoted by the same reference numerals.

[0046] The auxiliary device 20A is equipped with a magnetic material 22A at a distance L5 from the tip of the auxiliary device 20A. The magnetic material 22A can be attracted to the magnetic material 14 of the catheter 10 by magnetic force. Distance L5 (an example of a second distance) may be shorter than distance L1. In this case, when the magnetic material 22A of the auxiliary device 20A is joined to the magnetic material 14, the tip of the auxiliary device 20A is located proximal to the tip of the catheter 10, so that the tip of the auxiliary device 20A does not come into contact with the embolic material and interfere with joining with the magnetic material 14. Distance L1 may be, for example, 0.5 mm or more and 500 mm or less. Distance L1 may be, for example, 0.5 mm or more and 100 mm or less.

[0047] Distance L5 may be shorter than distance L2. In this case, when the magnetic material 22A of the auxiliary device 20A is joined to the magnetic material 14, the tip of the auxiliary device 20A will be located proximal to the marker 13 of the catheter 10. Therefore, even if the embolic material is trapped up to the marker 13 of the catheter 10, it is possible to appropriately prevent the tip of the auxiliary device 20A from coming into contact with the embolic material when the magnetic material 22A is joined to the magnetic material 14. Distance L5 may be, for example, 0 mm or more and 10 mm or less, as long as it is shorter than distance L2.

[0048] 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.

[0049] The magnetic materials 14 and 15 described above may be formed over the entire radial length of the layer, or they may be formed only on a portion of the layer. For example, as shown in Figure 6, when the auxiliary device 20 is inserted into the lumen 10a of the catheter 10, the magnetic material 14 may be formed only on the lumen 10a side of the layer, and the radially outer portion may have a structure similar to the other parts of the shaft 11.

[0050] This disclosure is not limited to the configuration of the embodiments described above, but is intended to include all modifications within the meaning and scope of the claims as shown, and equivalents thereof.

Claims

1. The device comprises a long catheter (10, 10A) and a long auxiliary device (20) that is separate from the catheter (10). The catheter (10, 10A) has a first magnetic material (14) located at a position a distance (L1) from its tip toward the proximal end, The auxiliary device (20, 20A) has a second magnetic material (22, 22A) located at a second distance shorter than the first distance from its tip, which is capable of magnetically attracting the first magnetic material (14). Catheter assembly (1).

2. The catheter (10) is provided with a radiopaque marker (13) between its tip and the first magnetic material (14), The second distance is less than or equal to the distance (L2) between the marker (13) and the first magnetic material (14). The catheter assembly (1) according to claim 1.

3. The longitudinal length (L4) of the auxiliary device (20) of the second magnetic material (22) is longer than the longitudinal length (L3) of the catheter (10, 10A) of the first magnetic material (14). A catheter assembly (10) according to claim 1 or claim 2.

4. At least one of the first magnetic material (14) and the second magnetic material (22) is a permanent magnet. A catheter assembly (1) according to any one of claims 1 to 3.

5. The first magnetic material (14) and the second magnetic material (22, 22A) are radiopaque. A catheter assembly (1) according to any one of claims 1 to 4.

6. The catheter (10A) is The third magnetic material (15) is located on the proximal end side of the first magnetic material. A catheter assembly (1) according to any one of claims 1 to 5.

7. The auxiliary device (20) is movable at its tip end through the lumen (10a) of the catheter (10) toward the tip end of the catheter (10). A catheter assembly (1) according to any one of claims 1 to 6.

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