Catheter for treatment of venous thrombosis

Abstract

To provide a catheter for venous thrombus treatment which shortens the treatment time of a lesion part.SOLUTION: A catheter 10 for venous thrombus treatment treats a lesion 16 having an organized thrombus 20 of a vein 14 in a living body 12. A catheter for venous thrombosis treatment includes a first catheter 24, and a second catheter 26 movably inserted into a first lumen 241 of the first catheter and having an outer diameter D2 smaller than an outer diameter D of organized thrombi. The second catheter is projectable distally from the distal end 321 of the first catheter.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a catheter for venous thrombosis treatment. [Background technology]

[0002] Patent Document 1 discloses a treatment method for deep venous thrombosis (DVT). In this treatment method, an obstructed area (thrombus area) in a vein of a living body is identified based on intravascular images, a catheter for treating venous thrombosis is passed through the obstructed area, and then a treatment balloon is delivered to the penetration area and expanded to treat the obstructed area. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6735320 Summary of the Invention [Problem to be solved by the invention]

[0004] In general, in deep vein thrombosis, veins are dilated and thinner than normal blood vessels. Furthermore, an occlusion (organized thrombus) may form between the dilated vein segments, resulting in the outer diameter of the occlusion being smaller than the outer diameter of the dilated vein segment. When treating an occlusion segment with a catheter for treating venous thrombosis, it is necessary to avoid perforation of the vein in the dilated and thinner vein segment, and to allow sufficient time for the catheter to reach the occlusion segment (organized thrombus), which is difficult to penetrate, and then form a penetration section through the occlusion segment. This results in a problem of prolonged treatment times for occlusion segments using a catheter for treating venous thrombosis.

[0005] The present invention aims to solve the above-mentioned problems. [Means for solving the problem]

[0006] (1) A first aspect of the present invention is a catheter for treating venous thrombosis for treating a lesion having an organized thrombus sandwiched between a venous portion having a larger diameter than that of a normal blood vessel in the direction of extension of the venous blood vessel in a living body, the catheter comprising: a first catheter having a first lumen and adapted to be inserted into the skin of the living body; and a second catheter movably inserted into the first lumen of the first catheter, having an outer diameter smaller than that of the organized thrombus, and adapted to protrude distally from the distal end of the first catheter.

[0007] With this catheter for venous thrombosis treatment, when the catheter for venous thrombosis treatment is advanced into a vein and the lesion is punctured by the second catheter, the second catheter is suitably backed up in the direction of advancement by the first catheter, making it easier to penetrate the lesion (organized thrombus). This reduces the time required to treat the lesion with the catheter for venous thrombosis treatment. Compared to a single catheter configuration, the outer diameter of the first catheter is increased to increase rigidity, and the first catheter guides the second catheter to increase support, allowing the second catheter to be advanced stably and straight in the direction of advancement.

[0008] (2) In the catheter for venous thrombosis treatment described in (1) above, the outer diameter of the first catheter may be smaller than the outer diameter of the organized thrombus.

[0009] With this configuration, when a catheter for venous thrombosis treatment is inserted into a vein from the peripheral side of a lesion in a living body, the first catheter, which has a smaller diameter than the organized thrombus, can be penetrated into the lesion (organized thrombus) together with the second catheter.

[0010] (3) In the catheter for venous thrombosis treatment described in (1) above, the outer diameter of the first catheter may be larger than the outer diameter of the organized thrombus.

[0011] This configuration increases the rigidity of the first catheter and allows the catheter for venous thrombosis treatment to be inserted into the vein from the central side, where the diameter of the blood vessel is larger than that of the distal side, thereby further increasing the support force of the second catheter provided by the first catheter.

[0012] (4) The catheter for venous thrombosis treatment described in any one of (1) to (3) above may further include a third catheter that is movably inserted into the first lumen of the first catheter, has a third lumen into which the second catheter is inserted, and is capable of protruding distally from the distal end of the first catheter.

[0013] With this configuration, by guiding the outside of the second catheter with the third catheter, bending of the second catheter can be effectively suppressed, and the support force of the second catheter can be improved, thereby increasing the penetration ability of the second catheter into the lesion.

[0014] (5) In the catheter for venous thrombosis treatment according to any one of (1) to (4) above, the second catheter may have a second lumen, and a guidewire may be inserted through the second lumen.

[0015] (6) A second aspect of the present invention is a method for treating a lesion having an organized thrombus sandwiched between venous portions having a larger diameter than that of normal blood vessels in the direction of extension of the vein in a living body using a catheter for venous thrombosis treatment, the catheter for venous thrombosis treatment comprising: a first catheter having a first lumen and being inserted into the skin of the living body; and a second catheter that is movably inserted into the first lumen of the first catheter, has an outer diameter smaller than that of the organized thrombus, and is capable of protruding distally from the tip of the first catheter; the method for treating a lesion having the organized thrombus using a catheter for venous thrombosis treatment comprises identifying the lesion having the organized thrombus, advancing the catheter for venous thrombosis treatment along the vein, and, after the tip of the catheter for venous thrombosis treatment reaches the lesion, penetrating at least the second catheter of the first and second catheters into the lesion.

[0016] According to this treatment method, when a catheter for venous thrombosis treatment is advanced into a vein and a second catheter is inserted into the lesion, the second catheter is suitably backed up by the first catheter, making it easier to penetrate the lesion (organized thrombus). This shortens the treatment time for the lesion using a catheter for venous thrombosis treatment. Compared to a single catheter configuration, the outer diameter of the first catheter is increased to increase rigidity, and the second catheter is guided by the first catheter, allowing the second catheter to advance stably and straight in the direction of advancement.

[0017] (7) In the treatment method described in (6) above, after forming a penetration portion in the lesion by penetrating at least the second catheter into the lesion, a treatment catheter may be inserted into the penetration portion in the lesion to treat the lesion.

[0018] According to this treatment method, a penetration portion is formed in the lesion with the second catheter of the venous thrombosis treatment catheter, and the treatment catheter can be inserted into the penetration portion to reliably treat the lesion. [Effects of the Invention]

[0019] According to the present invention, a catheter for venous thrombosis treatment includes a second catheter that is movably inserted into the first lumen of the first catheter, has an outer diameter smaller than the outer diameter of the organized thrombus, and is capable of protruding distally from the distal end of the first catheter. When the catheter for venous thrombosis treatment is advanced into the vein and the lesion is punctured with the second catheter, the second catheter is suitably backed up by the first catheter. This makes it easier to penetrate the lesion (organized thrombus). This shortens the time required to treat the lesion with the catheter for venous thrombosis treatment. Compared to a catheter consisting of a single catheter, the outer diameter of the first catheter is increased to increase its rigidity, and the first catheter guides the second catheter to increase its support, allowing the second catheter to be advanced stably and straight in the direction of advancement. [Brief explanation of the drawings]

[0020] [Figure 1] FIG. 1 is an explanatory diagram showing the initial state when treatment is performed using a catheter for venous thrombosis treatment according to an embodiment of the present invention. [Figure 2] FIG. 2 is an explanatory diagram showing a state in which a second catheter of the venous thrombosis treatment catheter has been penetrated into a lesion. [Figure 3] FIG. 3 is an explanatory diagram showing a state in which the treatment portion of the treatment catheter is inserted into the penetration portion of the lesion. [Figure 4] FIG. 4 is an explanatory diagram showing a case where a venous thrombosis treatment catheter is inserted into a central blood vessel for treatment. DETAILED DESCRIPTION OF THE INVENTION

[0021] 1, the catheter 10 for venous thrombosis treatment according to this embodiment is used, for example, to treat a lesion 16 (such as a narrowed or blocked area) that has developed in a blood vessel 141 of a vein 14 in a living body 12. Specifically, the catheter 10 for venous thrombosis treatment is used to treat DVT (Deep Venous Thrombosis, lesion 16), in which an organized thrombus 20 has developed from a thrombus 18 in the blood vessel 141 of the vein 14.

[0022] The catheter 10 for venous thrombosis treatment can be inserted into a blood vessel 141 of a vein 14 in a living body 12 and advanced along the blood vessel 141. The catheter 10 for venous thrombosis treatment is a catheter that advances along the blood vessel 141 toward the peripheral side (ankle side) or central side (heart side) of the living body 12 toward a lesion 16 in the vein 14.

[0023] The catheter 10 for venous thrombosis treatment comprises a first catheter 24 having a first lumen 241, a second catheter 26 movably inserted into the first lumen 241, a third catheter 28 disposed between the first catheter 24 and the second catheter 26, and a guide wire 30 inserted into the second lumen 261 of the second catheter 26.

[0024] The first catheter 24 has a tubular first catheter body 32 with a first lumen 241. The first catheter 24 is, for example, a sheath introducer. The first catheter body 32 is formed from a flexible resin material. The first catheter body 32 is percutaneously inserted into a blood vessel 141 of a vein 14 of a living body 12. The distal end 321 of the first catheter body 32 has a tapered outer surface that decreases in diameter toward the distal end. The first lumen 241 is disposed inside the first catheter body 32. The first lumen 241 extends along the first catheter body 32. The proximal end of the first catheter body 32 is provided with a hub (not shown), and the proximal end of the hub is open. When inserting the venous thrombosis treatment catheter 10 into the blood vessel 141, a dilator (not shown) may be inserted into the first lumen 241 of the first catheter 24, and the hub (not shown) may be a hemostatic valve.

[0025] The outer diameter D1 (outer peripheral diameter) of the first catheter body 32 is smaller than the outer diameter D of the organized thrombus 20 (lesion 16) in a cross-section orthogonal to the extending direction of the blood vessel 141 (D1 < D).

[0026] The second catheter 26 has a tubular second catheter body 36 having a second lumen 261. The second catheter 26 is, for example, a micro catheter or a support catheter. The second catheter body 36 is formed of a resin material having flexibility. The outer diameter D2 of the second catheter body 36 is smaller than the outer diameter D1 of the first catheter 24 (D2 < D1). That is, the outer diameter D2 of the second catheter body 36 is smaller than the outer diameter D of the organized thrombus 20 in a cross-section orthogonal to the extending direction of the blood vessel 141 (D2 < D).

[0027] The second catheter body 36 may be inserted into the first lumen 241 of the first catheter 24 via the third catheter 28. The second catheter body is provided movably along the first lumen 241. The distal end portion 361 of the second catheter body 36 has a tapered outer peripheral surface that tapers in the distal end direction.

[0028] When the second catheter 26 moves along the first lumen 241 of the first catheter 24, the second catheter 26 is guided (supported) in the moving direction by the first catheter 24 via the third catheter 28. The distal end portion 361 of the second catheter 26 can project in the distal end direction from the distal end portion 321 of the first catheter 24. The distal end portion 361 of the second catheter body 36 is not made of a soft material such as a rubber material (elastomer material), but has a hardness suitable for treating the lesion 16 (organized thrombus 20). The second lumen 261 is disposed inside the second catheter body 36. The second lumen 261 extends along the second catheter body 36. The second lumen 261 is a passage through which the guide wire 30 can be inserted.

[0029] The proximal end of the second catheter body 36 is provided with a hub (not shown), and the proximal end of the hub is open. A guide wire 30 can be inserted into the second lumen 261 through the hub.

[0030] The third catheter 28 has a tubular third catheter body 40 having a third lumen 281. The third catheter 28 is, for example, a contrast catheter or a guiding catheter. The third catheter body 40 is formed from a resin material having flexibility. The outer diameter D3 of the third catheter body 40 is smaller than the outer diameter D1 of the first catheter 24 and larger than the outer diameter D2 of the second catheter 26 (D2 < D3 < D1). The distal end portion 401 of the third catheter body 40 has a tapered outer peripheral surface that tapers in the distal end direction. The distal end portion 401 of the third catheter body 40 is not made of a soft material such as a rubber material (elastomer material), but has a hardness suitable for treating the lesion 16. Also, the third catheter 28 may have a soft tip with a flexible distal end portion, such as a coronary guiding catheter.

[0031] The third catheter body 40 is inserted into the first lumen 241 of the first catheter 24. The third catheter body 40 is movable along the first lumen 241.

[0032] The third lumen 281 is disposed inside the third catheter body 40. The third lumen 281 extends along the third catheter body 40. The second catheter body 36 is movably provided in the third lumen 281. The proximal end of the third catheter body 40 is provided with a hub (not shown), and the proximal end of the hub is open. The second catheter 26 can be inserted into the third lumen 281 through the hub.

[0033] When the second catheter 26 moves along the third lumen 281 of the third catheter 28, the second catheter 26 is guided (supported) in the movement direction by the third catheter 28. The tip portion 401 of the third catheter 28 can protrude distally from the tip portion 321 of the first catheter 24 (see FIG. 2). That is, the third catheter 28 supports the radially outer side of the second catheter 26. In other words, the third catheter body 40 is disposed between the first lumen 241 of the first catheter body 32 and the outer peripheral surface of the second catheter body 36.

[0034] The venous thrombosis treatment catheter 10 is not limited to a configuration including three catheters (first to third catheters 24, 26, 28). It may also be configured to include the first and second catheters 24, 26 without including the third catheter 28, and in which the second catheter body 36 is directly inserted into the first lumen 241 of the first catheter body 32.

[0035] Next, we will explain the treatment of deep vein thrombosis (DVT) using the venous thrombosis treatment catheter 10. Figure 1 is a schematic cross-sectional view showing the peripheral portion of an organized thrombus 20 (lesion 16) that has formed in a blood vessel 141 of a vein 14 in the lower limb.

[0036] As shown in FIG. 1 , a thrombus 18 forms in a blood vessel 141 in a vein 14 of a living body 12, and a portion of the thrombus 18 organizes to form an organized thrombus 20 (lesion 16). The right side of the organized thrombus 20 is the central side (heart side) and downstream in the blood flow. The left side of the organized thrombus 20 is the peripheral side (ankle side) and upstream in the blood flow. Hereinafter, the blood vessel 141 downstream (right side) of the organized thrombus 20 will be referred to as a central vascular portion 441, and the blood vessel 141 upstream (left side) of the organized thrombus 20 will be referred to as a peripheral vascular portion 461. The central vascular portion 441 has a relatively large diameter compared to the peripheral vascular portion 461. The peripheral vascular portion 461 is a peripheral blood vessel in which the diameter of the blood vessel 141 is relatively small compared to the central vascular portion 441.

[0037] In a peripheral blood vessel portion 461, which is on the peripheral side of the organized thrombus 20 (lesion portion 16), blood flow is stagnated by the thrombus 18 (organized thrombus 20), and the blood presses the blood vessel 141 radially outward, thereby forming a peripheral enlarged-diameter portion 462. The peripheral enlarged-diameter portion 462 has a diameter larger than that of a blood vessel 141 in a normal state in which no thrombus 18 has formed (hereinafter, normal blood vessel 22). The peripheral enlarged-diameter portion 462 is formed upstream of the organized thrombus 20. The peripheral enlarged-diameter portion 462 is formed within a predetermined range in the extension direction (direction of arrows A and B) of the blood vessel 141.

[0038] In a central blood vessel portion 441, which is central to the organized thrombus 20 (lesion 16), blood flow is stagnated by the thrombus 18 (organized thrombus 20), and the blood presses the blood vessel 141 radially outward, thereby forming a central enlarged-diameter portion 442. The central enlarged-diameter portion 442 has a diameter larger than that of a normal blood vessel 22 in which no thrombus 18 has formed. The central enlarged-diameter portion 442 is formed downstream of the organized thrombus 20. The central enlarged-diameter portion 442 is formed within a predetermined range in the extension direction (directions of arrows A and B) of the blood vessel 141. That is, in the extension direction of the blood vessel 141 of the vein 14 in the living body 12, the organized thrombus 20 (lesion 16) is sandwiched between venous portions (peripheral enlarged-diameter portion 462, central enlarged-diameter portion 442) whose diameter is larger than that of the normal blood vessel 22.

[0039] Hereinafter, as shown in FIG. 1, a case will be described in which an venous thrombosis treatment catheter 10 is inserted from a peripheral blood vessel portion 461, which is on the peripheral side of the organized thrombus 20, to treat the organized thrombus 20 (lesion portion 16).

[0040] First, a medical professional (not shown) identifies the position of organized thrombus 20 in vein 14 of living body 12, for example, by X-ray imaging, and then percutaneously inserts tip 321 of first catheter 24 of venous thrombosis treatment catheter 10 into peripheral vascular portion 461 of blood vessel 141. Note that the method for identifying the position of organized thrombus 20 is not limited to X-ray imaging. Other methods may also be used to identify the position of organized thrombus 20 in living body 12. Below, a case where a lesion 16 is treated under X-ray imaging will be described.

[0041] Within the peripheral blood vessel portion 461, the tip 321 of the first catheter 24 is advanced centrally (in the direction of arrow A) along a guide wire (not shown) toward the organized thrombus 20, and the tip 321 of the first catheter 24 is placed upstream of the organized thrombus 20. At this time, a medical professional (not shown) can visually confirm the position of the tip 321 of the first catheter 24 under X-ray imaging via a display or the like, thereby performing the procedure.

[0042] Next, the distal end 401 of the third catheter 28 is inserted into the first lumen 241 from the proximal end (hub) of the first catheter 24, and the distal end 401 is advanced toward the distal end 321 of the first catheter 24 under X-ray imaging. At this time, the outer peripheral surface of the third catheter 28 is supported by the first catheter 24, and the third catheter 28 is guided toward the distal end. The distal end 401 of the third catheter 28 is placed inside the distal end 321 of the first catheter 24.

[0043] Next, the distal end 361 of the second catheter 26 is inserted into the third lumen 281 from the proximal end (hub) of the third catheter 28, and the distal end 361 is advanced toward the distal end 321 of the first catheter 24 and the distal end 401 of the third catheter 28 under X-ray imaging. At this time, the outer peripheral surface of the second catheter 26 (second catheter main body 36) is supported by the third catheter 28, and the second catheter 26 is guided toward the distal end. The distal end 361 of the second catheter 26 is placed inside the distal end 321 of the first catheter 24. A guidewire 30 is inserted into the second lumen 261 from the proximal end (hub) of the second catheter 26. The distal end of the guidewire 30 is advanced to the distal end 361 of the second catheter 26.

[0044] As shown in Figure 2, the second and third catheters 26, 28 are advanced toward the distal end (direction of arrow A) relative to the first catheter 24, and the distal end 361 of the second catheter 26 and the distal end 401 of the third catheter 28 protrude distally from the distal end 321 of the first catheter 24, thereby being inserted into the peripheral blood vessel portion 461.

[0045] By further advancing the second catheter 26 in the distal direction relative to the third catheter 28, the distal end 361 of the second catheter 26 together with the guidewire 30 protrudes distally (toward the central region) from the distal end 401 of the third catheter 28. At this time, the outer peripheral surface of the second catheter 26 is supported in the advancing direction of the second catheter 26 by the third catheter 28, and the second catheter 26 is guided distally.

[0046] With the tip of the guidewire 30 protruding distally (in the direction of arrow A) from the tip 361 of the second catheter 26, the tip 361 of the second catheter 26 is advanced centrally (in the direction of arrow A) along the guidewire 30 toward the organized thrombus 20. By further moving the tip 361 of the second catheter 26 distally, the guidewire 30 abuts against and punctures the upstream end 201 of the organized thrombus 20, and then the tip 361 advances into the organized thrombus 20. As the tip 361 of the second catheter 26 advances to the central blood vessel portion 441, the tip 361 digs into the organized thrombus 20 or passes through voids in the organized thrombus 20 to form a penetration 48 inside the organized thrombus 20. The penetration 48 is a perforation 50 that penetrates the organized thrombus 20 along the extension direction of the blood vessel 141 (in the direction of arrows A and B). The penetrating part 48 penetrates the organized thrombus 20 from the upstream end 201 to the downstream end 202. At this time, the outer peripheral surface of the second catheter 26 is supported in the direction of advancement of the second catheter 26 by the third catheter 28, and the second catheter 26 is guided toward the distal end.

[0047] As shown in FIG. 3, after the penetration portion 48 is formed in the organized thrombus 20, the second catheter 26 is removed from the penetration portion 48. After the second and third catheters 26, 28 are removed from the first catheter 24, the distal end portion of the treatment catheter 52 is inserted into the first lumen 241 of the first catheter 24 from a hub (not shown). The treatment catheter 52 is a catheter having a treatment portion 54 that can be expanded, for example, by the operation of a medical practitioner, at the distal end portion. The treatment portion 54 is, for example, a balloon, a stent, or an atherectomy catheter. The treatment portion 54 of the treatment catheter 52 moves along the first lumen 241 and projects in the distal end direction from the distal end portion 321 of the first catheter 24, and then the treatment portion 54 is inserted into the penetration portion 48 (perforation 50) of the organized thrombus 20. By operating the treatment portion in the penetration portion 48, the treatment portion 54 expands and the organized thrombus 20 is spread, and treatment is performed (see the two-dot chain line shape in FIG. 3). After the penetration portion 48 is formed in the organized thrombus 20, only the second catheter 26 may be removed from the first catheter 24, and the treatment catheter may be inserted into the third lumen 281 of the third catheter 28 and advanced.

[0048] Note that, in the method for treating the organized thrombus 20, it is not limited to the case where only the second catheter 26 penetrates the organized thrombus Since the outer diameter D1 of the first catheter 24 is smaller than the outer diameter D of the organized thrombus 20 (D1<D), the distal end portion 321 of the first catheter 24 may be advanced into the organized thrombus 20 to form the penetration portion 48 prior to the second catheter 26. Since the outer diameter D3 of the third catheter 28 is smaller than the outer diameter D1 of the first catheter 24, the distal end portion 401 of the third catheter 28 may be advanced into the organized thrombus 20 to form the penetration portion 48 prior to the second catheter 26.

[0049] Treatment of organized thrombus 20 using the venous thrombosis treatment catheter 10 is not limited to the case where the venous thrombosis treatment catheter 10 is inserted from the peripheral blood vessel portion 461. For example, as shown in Fig. 4, treatment may be performed by inserting the venous thrombosis treatment catheter 10 from the central blood vessel portion 441, which is on the central side with respect to the organized thrombus 20. In this case, it is possible to use a venous thrombosis treatment catheter 10 in which the outer diameter D1 of the first catheter 24 is larger than the outer diameter D of the organized thrombus 20 (D1>D). This is because the lumen diameter of the blood vessel 141 in the central blood vessel portion 441 is larger than the lumen diameter of the blood vessel 141 in the peripheral blood vessel portion 461.

[0050] This embodiment has the following advantages.

[0051] 1, the catheter 10 for venous thrombosis treatment is used to treat a lesion 16 having an organized thrombus 20 sandwiched between venous portions (central enlarged diameter portion 442, peripheral enlarged diameter portion 462) that are enlarged in diameter compared to a normal blood vessel 22 in the extension direction (direction of arrows A and B) of a blood vessel 141 of a vein 14 in a living body 12. The catheter 10 for venous thrombosis treatment comprises a first catheter 24 having a first lumen 241 and adapted to be inserted into the skin of the living body 12, and a second catheter 26 that is movably inserted into the first lumen 241 of the first catheter 24, has an outer diameter D2 smaller than the outer diameter D of the organized thrombus 20, and is capable of protruding distally from the distal end portion 321 of the first catheter 24.

[0052] According to this configuration, when the catheter 10 for venous thrombosis treatment is advanced into the vein 14 and the second catheter 26 is inserted into the lesion 16 (organized thrombus 20), the second catheter 26 is suitably backed up by the first catheter 24, making it easier to penetrate the lesion 16 (organized thrombus 20). This reduces the time required to treat the lesion 16 with the catheter 10 for venous thrombosis treatment. Compared to a configuration consisting of a single catheter, the outer diameter D1 of the first catheter 24 is increased to increase rigidity, and the second catheter 26 is guided by the first catheter 24, allowing the second catheter 26 to advance stably and straight in the direction of advancement.

[0053] By forming the outer diameter D1 of the first catheter 24 smaller than the outer diameter D of the organized thrombus 20, when the catheter 10 for treating venous thrombosis is inserted into the vein 14 from the peripheral side of the lesion 16 of the living body 12, the first catheter 24, which has a smaller diameter than the organized thrombus 20, can be penetrated into the lesion 16 (organized thrombus 20) together with the second catheter 26.

[0054] As shown in Figure 4, by forming the outer diameter D1 of the first catheter 24 larger than the outer diameter D of the organized thrombus 20, the rigidity of the first catheter 24 is increased, and the catheter 10 for venous thrombosis treatment can be inserted into the vein 14 from the central side where the diameter of the blood vessel 141 is larger than that of the distal side, thereby further increasing the support force of the second catheter 26 by the first catheter 24.

[0055] 1, the venous thrombosis treatment catheter 10 is movably inserted into the first lumen 241 of the first catheter 24, has a third lumen 281 into which the second catheter 26 is inserted, and is equipped with a third catheter 28 that can protrude distally from the distal end 321 of the first catheter 24. In this way, by guiding the outside of the second catheter 26 with the third catheter 28, bending of the second catheter 26 is suitably suppressed, and the support force of the second catheter 26 is improved, thereby enabling the second catheter 26 to penetrate the lesion 16 more easily.

[0056] In a treatment method using a catheter 10 for venous thrombosis treatment, a lesion 16 having an organized thrombus 20 in a vein 14 is identified, the catheter 10 for venous thrombosis treatment is advanced along the vein 14, and after the tip of the catheter 10 for venous thrombosis treatment reaches the lesion 16, at least the second catheter 26 of the first and second catheters 24, 26 is penetrated into the lesion 16.

[0057] According to this treatment method, when the venous thrombosis treatment catheter 10 is advanced into the vein 14 and the lesion 16 is punctured by the second catheter 26, the second catheter 26 is suitably backed up by the first catheter 24, making it easier to penetrate the lesion 16 (organized thrombus 20). This reduces the time required to treat the lesion 16 with the venous thrombosis treatment catheter 10. Compared to a single catheter configuration, the outer diameter D1 of the first catheter 24 is increased to increase rigidity, and the second catheter 26 is guided by the first catheter 24, allowing the second catheter 26 to advance stably and straight in the direction of advancement.

[0058] By forming a penetration 48 in the lesion 16 by penetrating at least the second catheter 26 into the lesion 16, and then inserting a treatment catheter 52 into the penetration 48 in the lesion 16 to treat the lesion 16, the penetration 48 in the lesion 16 is formed using the second catheter 26, and the treatment catheter 52 can be inserted into the penetration 48 to reliably treat the lesion 16 with the treatment catheter 52.

[0059] The present invention is not limited to the above disclosure, and various configurations can be adopted without departing from the gist of the present invention. [Explanation of symbols]

[0060] 10...Venous thrombosis treatment catheter 12... Living organisms 14...vein 16...Affected area 20…Organized thrombus 22…Normal blood vessels 24...First catheter 26...Second catheter 28...Third catheter 141...Vessel 241...1st lumen 261...2nd lumen 281...3rd lumen

Claims

1. A catheter for venous thrombosis treatment for treating a lesion having an organized thrombus sandwiched in a venous portion having a diameter larger than that of a normal blood vessel in the extension direction of the vein in a living body, a first catheter having a first lumen and adapted to be inserted into the skin of the living body; a second catheter that is movably inserted into the first lumen of the first catheter, has an outer diameter smaller than an outer diameter of the organized thrombus, and is protruding from the distal end of the first catheter in a distal direction; A catheter for venous thrombosis treatment comprising:

2. The catheter for venous thrombosis treatment according to claim 1, A catheter for intravenous thrombosis treatment, wherein the outer diameter of the first catheter is smaller than the outer diameter of the organized thrombus.

3. The catheter for venous thrombosis treatment according to claim 1, A catheter for venous thrombosis treatment, wherein the outer diameter of the first catheter is larger than the outer diameter of the organized thrombus.

4. The catheter for venous thrombosis treatment according to any one of claims 1 to 3, A catheter for venous thrombosis treatment comprising a third catheter that is movably inserted into the first lumen of the first catheter, has a third lumen into which the second catheter is inserted, and is capable of protruding distally from the distal end of the first catheter.

5. The catheter for venous thrombosis treatment according to claim 1, The second catheter has a second lumen through which a guidewire is inserted.

6. A method for treating a lesion having an organized thrombus sandwiched between a venous portion having a larger diameter than a normal blood vessel in the direction of extension of the vein in a living body using a catheter for venous thrombosis treatment, comprising: The venous thrombosis treatment catheter includes a first catheter having a first lumen and adapted to be inserted into the skin of the living body; a second catheter that is movably inserted into the first lumen of the first catheter, has an outer diameter smaller than an outer diameter of the organized thrombus, and is protruding from the distal end of the first catheter in a distal direction; Equipped with identifying the lesion having the organized thrombus; A treatment method using a catheter for venous thrombosis treatment, comprising: advancing the catheter for venous thrombosis treatment along the vein; and, after the tip of the catheter for venous thrombosis treatment reaches the lesion, penetrating at least the second catheter of the first and second catheters into the lesion.

7. 7. The method of treatment according to claim 6, A treatment method using a catheter for venous thrombosis treatment, comprising: forming a penetration portion in the lesion by penetrating at least the second catheter into the lesion; and then inserting a treatment catheter into the penetration portion in the lesion to treat the lesion.

Images