Guide extension catheter

Abstract

This guide extension catheter (10) comprises a tubular distal shaft (12) and a proximal shaft (50) that is made of a metal wire and connected to the proximal end of the distal shaft. The distal shaft is provided with a derived quantity-controlling marker (24) for controlling the derived quantity from a guiding catheter, said quantity-controlling marker extending from a preset position in the longitudinal direction toward the distal end of the distal shaft. The derived quantity-controlling marker comprises a resin to which a metal powder is added. The length from the base part of the derived quantity-controlling marker to the distal end of the distal shaft is a preset length.

Description

Technical Field

[0001] The present invention relates to a guide extension catheter.

Background Art

[0002] Conventionally, when performing coronary artery treatment such as percutaneous coronary intervention (PCI) or cardiac catheter examination, a guiding catheter is used. For example, the guiding catheter is inserted from the outside of the skin through the aorta to the entrance of the coronary artery, and a treatment catheter or a diagnostic catheter such as a balloon catheter or a stent delivery catheter is inserted into the coronary artery from the tip of the guiding catheter to perform treatment or diagnosis. On the other hand, even when calcification occurs inside the coronary artery or the coronary artery is tortuous, in order to smoothly reach the lesion or diagnostic part with a treatment or diagnostic catheter, a guide extension catheter as described in Patent Document 1 is used.

[0003] The guide extension catheter passes through the guiding catheter, a part of which is led out from the tip of the guiding catheter and inserted into the coronary artery, secures the path of the treatment or diagnostic catheter at the difficult-to-pass site, and supports the catheter to smoothly reach the lesion or diagnostic part.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] When a guide extension catheter is inserted into the coronary artery, if the length of the guide extension catheter extended from the tip of the guiding catheter greatly exceeds a predetermined length, there is a possibility that blood flow obstruction may occur due to the extended guide extension catheter. Thus, it is recommended that the guide extension catheter be configured to keep the length extended from the tip of the guiding catheter below a predetermined length (e.g., 15 cm). However, currently, a technician such as an operator visually determines the length of the guide extension catheter extended from the guiding catheter while looking at an X-ray irradiation image, and ensures that the extended length does not exceed the predetermined length. As a result, since the extended length is based on the subjective judgment of the technician, there is a possibility that the extended length may greatly exceed the predetermined length during treatment. In addition, since the technician needs to pay excessive attention so that the extended length does not greatly exceed the predetermined length, the burden on the technician may increase.

[0006] An object of the present invention is to provide a guide extension catheter capable of stably and easily regulating the length extended from a guiding catheter.

Means for Solving the Problem

[0007] The guide extension catheter according to the present invention includes a tubular distal shaft and a proximal shaft made of a metal wire connected to the proximal end portion of the distal shaft. The distal shaft includes an extension amount regulating marker for regulating the amount of extension from the guiding catheter, which extends from a predetermined position in the longitudinal direction toward the distal end of the distal shaft. The extension amount regulating marker has metal powder mixed in a resin, and the length from the proximal end of the extension amount regulating marker to the distal end of the distal shaft is a predetermined length.

[0008] According to the above configuration, when a technician guides out the guide extension catheter from the tip of the guiding catheter while looking at the X-ray irradiated image, the length of the guide-out can be restricted at the position where the proximal end of the marker for restricting the guide-out amount in the guide-out portion is visible. As a result, the technician can stably and easily restrict the guide-out length so that the guide-out length does not greatly exceed a predetermined length.

[0009] The guide extension catheter according to the present invention includes a cylindrical distal shaft and a proximal shaft made of a metal wire connected to the proximal end portion of the distal shaft. The distal shaft is formed in a portion including the distal end, and includes a tip marker in which metal powder is mixed in resin, and a marker for restricting the guide-out amount that continuously extends in the longitudinal direction from the proximal end of the tip marker and has a proximal end at a position where the length from the distal end of the distal shaft is a predetermined length. The marker for restricting the guide-out amount is a marker for restricting the guide-out amount in which metal powder is mixed in resin. The tip marker and the marker for restricting the guide-out amount are guide extension catheters that are visually recognized with different shades under fluoroscopy.

[0010] According to the above configuration, when a technician guides out the guide extension catheter from the tip of the guiding catheter while looking at the X-ray irradiated image, the length of the guide-out can be restricted at the position where the proximal end of the marker for restricting the guide-out amount in the guide-out portion is visible. As a result, the technician can stably and easily restrict the guide-out length so that the guide-out length does not greatly exceed a predetermined length. Further, since the tip marker and the marker for restricting the guide-out amount are visually recognized with different shades under fluoroscopy, the technician can more easily recognize the position of the distal end of the guide extension catheter under fluoroscopy. Further, since the tip marker has metal powder mixed in the resin, even if the distal end of the guide extension catheter is deformed, it easily returns to its original shape. Due to this property of the distal end deforming and returning to its original state, even when passing through a hard calcified lesion, the distal end can pass through while deforming. Thereby, a configuration excellent in insertability and blood vessel followability can be obtained.

[0011] The guide extension catheter according to the present invention includes a tubular distal shaft and a proximal shaft made of a metal wire connected to the proximal end of the distal shaft. The distal shaft includes a tip marker formed in a portion including the distal end, in which metal powder is mixed in resin, and a lead-out amount regulating marker that extends from a position longitudinally spaced from the proximal end of the tip marker toward the proximal end side of the distal shaft and has a proximal end at a position where the length from the distal end of the distal shaft is a predetermined length, and the lead-out amount regulating marker is made of resin in which metal powder is mixed. The tip marker and the lead-out amount regulating marker are different in shade and visible under fluoroscopy, and it is a guide extension catheter.

[0012] According to the above configuration, when the operator guides out the guide extension catheter from the tip of the guiding catheter while looking at the fluoroscopic image, the leading length can be restricted at the position where the proximal end of the lead-out amount regulating marker at the leading portion is visible. Thereby, the operator can stably and easily regulate the leading length so that the leading length does not greatly exceed the predetermined length. Further, since the tip marker and the lead-out amount regulating marker are different in shade and visible under fluoroscopy, the operator can more easily recognize the position of the distal end of the guide extension catheter under fluoroscopy. Further, since the tip marker and the lead-out amount regulating marker are arranged at intervals, the radiopaque markers of the treatment catheter or diagnostic catheter inserted inside the distal shaft of the guide extension catheter can be clearly visible under fluoroscopy at the portion corresponding to the above interval. Thereby, the position of the radiopaque marker of the catheter inserted inside the distal shaft of the guide extension catheter becomes easier for the operator to see under fluoroscopy.

[0013] A guide extension catheter according to the present invention includes a cylindrical distal shaft and a proximal shaft made of a metal wire and connected to the proximal end of the distal shaft, the distal shaft including a tip marker formed in a portion including the distal end and made of resin containing metal powder, and an output amount control marker extending longitudinally continuously from the base end of the tip marker and having a base end at a predetermined longitudinal position where the length from the distal end of the distal shaft is a predetermined length, the tip marker and the output amount control marker being made of resin containing metal powder, the tip marker and the output amount control marker being configured to be visually recognized by different shades under X-ray fluoroscopy, or a configuration in which the cylindrical distal shaft and the distal shaft are connected to each other. and a proximal shaft made of a metal wire and connected to the proximal end of the shaft, wherein the distal shaft is formed in a portion including the distal end and includes a tip marker made of resin with metal powder mixed in, and a delivery amount control marker for controlling the amount of delivery from the guiding catheter, the delivery amount control marker comprising metal powder mixed in resin, extending from a position spaced longitudinally from the base end of the tip marker toward the proximal end of the distal shaft and having its base end at a predetermined longitudinal position where the length from the distal end of the distal shaft is a predetermined length, wherein the tip marker and the delivery amount control marker are configured to be visually recognized as different shades under X-ray fluoroscopy, and the delivery amount control marker can be configured to be visually recognized as being lighter in shade than the tip marker under X-ray fluoroscopy.

[0014] According to the above configuration, the radiopaque marker of the treatment catheter or diagnostic catheter inserted inside the distal shaft of the guide extension catheter can be made visible under X-ray fluoroscopy, even in the portion where the derived amount control marker is provided. This allows the operator to always check the position of the radiopaque marker of the catheter inserted inside the distal shaft of the guide extension catheter under X-ray fluoroscopy, making it possible to perform the procedure with high accuracy without losing sight of the radiopaque marker.

[0015] In the guide extension catheter according to the present invention, the lead-out amount regulating marker and the tip marker can be configured such that the same kind of metal powder is mixed therein, and the weight ratio of the metal powder in the resin of the lead-out amount regulating marker is smaller than that of the tip marker.

[0016] According to the above configuration, since the same kind of metal powder is used for the lead-out amount regulating marker and the tip marker, the operation of manufacturing the guide extension catheter becomes easy, and the characteristics of the lead-out amount regulating marker and the tip marker are likely to be close to each other, so it becomes easy to process.

[0017] In the guide extension catheter according to the present invention, the predetermined length is 15 cm. According to the above configuration, the operator can stably and easily regulate the lead-out length so that the lead-out length of the guide extension catheter from the guiding catheter does not greatly exceed 15 cm.

[0018] In the guide extension catheter according to the present invention, the proximal end of the lead-out amount regulating marker can be configured to be disposed at a position spaced 5 cm or more from the proximal end of the distal shaft and on the distal end side of the distal shaft.

[0019] According to the above configuration, when the operator leads out the guide extension catheter from the tip of the guiding catheter while looking at the X-ray irradiation image, if the lead-out length is restricted at the position where the proximal end of the lead-out amount regulating marker in the lead-out portion is visible, the length from the proximal end of the lead-out portion to the proximal end of the distal shaft disposed in the guiding catheter can be sufficiently ensured. Thereby, it becomes easy to prevent all of the distal shaft from being led out from the tip of the guiding catheter and the proximal end of the distal shaft from being caught by the tip of the guiding catheter.

Effect of the Invention

[0020] According to the guide extension catheter of the present invention, the lead-out length from the guiding catheter can be stably and easily regulated

Brief Description of the Drawings

[0021]

Figure 1

Figure 2A

Figure 2B

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Modes for Carrying Out the Invention

[0022] Hereinafter, with reference to the drawings, an example of an embodiment of the present invention will be described in detail. The embodiment described below is merely an example, and the present invention is not limited to the following embodiment.

[0023] An example of a guide extension catheter 10 according to an embodiment will be described with reference to FIGS. 1 to 5. FIG. 1 shows a state in which a leading portion of the guide extension catheter 10 from a guiding catheter 100 is inserted into the coronary artery 102, and a stent delivery catheter 106 is led out from the distal end P of the leading portion. FIG. 2A is an overall view of the guide extension catheter 10. FIG. 2B is a longitudinal sectional view of the distal shaft 12 of the guide extension catheter 10.

[0024] As shown in FIG. 1, the guide extension catheter 10 is used together with a guiding catheter 100 when performing coronary artery treatment such as percutaneous coronary intervention (PCI) or cardiac catheter examination. In FIG. 1, the guiding catheter 100 is shown by a portion filled in black. For example, the guiding catheter 100 is percutaneously inserted with its end into the inlet Q of the coronary artery 102 through the femoral artery (not shown), and the guide extension catheter 10 is led out from the tip 101 of the guiding catheter 100 through the guiding catheter 100 and inserted into the coronary artery 102. Thereafter, a therapeutic or diagnostic catheter is inserted into the guide extension catheter 10. FIG. 1 shows an example in which a stent delivery catheter 106 having a stent 107 is inserted into the guide extension catheter 10 as an example of a therapeutic or diagnostic catheter. By using the guide extension catheter 10, it becomes easier to secure the path of the therapeutic or diagnostic catheter even when there is a calcified and raised portion as shown by the sandy portion in FIG. 1 on the inner surface of the coronary artery 102.

[0025] As shown in FIGS. 2A and 2B, the guide extension catheter 10 is a long catheter and includes a tubular distal shaft 12 and a proximal shaft 50 made of a wire and connected to the proximal end of the distal shaft 12. The distal end of the proximal shaft 50 is connected to a circumferential part of the outer peripheral surface of the distal shaft 12. Note that the distal end of the proximal shaft 50 is not limited to being connected to the outer peripheral surface of the distal shaft 12, and may be disposed, for example, between an inner layer 14 and an outer layer 18 of the distal shaft 12 described later. Also, in the present embodiment, the "proximal end side" or "base end side" refers to the rear side (the right side in FIG. 2A) with respect to the direction in which the guide extension catheter 10 is inserted into a blood vessel. Also, the "distal end side" or "tip side" refers to the front side (the left side in FIG. 2A) with respect to the direction in which the guide extension catheter 10 is inserted into a blood vessel.

[0026] As shown in FIG. 2B, the distal shaft 12 includes an inner layer 14 made of a resin, a reinforcing portion 16 provided on the outer periphery of the inner layer 14, and an outer layer 18 provided on the outer periphery of the reinforcing portion 16 and having a resin.

[0027] The inner layer 14 forms a lumen 15 for inserting another catheter therein. The resin material constituting the inner layer 14 is not particularly limited, and for example, polytetrafluoroethylene (PTFE) or the like is used. The inner layer 14 is not limited to being a single-layer tube, and may be a multi-layer tube made of the same or different materials.

[0028] The reinforcing portion 16 is formed by, for example, a braided body. The braided body is one in which a first base wire and a second base wire are braided in a mesh shape. For example, along a first direction inclined with respect to the longitudinal axis of the distal shaft 12, a plurality of first base wires are wound around the outside of the inner layer 14, and are inclined with respect to the longitudinal axis of the distal shaft 12, and a plurality of second base wires are wound around the outside of the inner layer 14 along a second direction intersecting the first direction. The first base wire and the second base wire are formed of a metal wire such as stainless steel or a resin wire. In addition, in FIG. 2B, as the reinforcing portion, a portion where the first base wire and the second base wire overlap at the intersection is shown. Further, the reinforcing portion 16 is not limited to one made of a braided body, and may be, for example, one formed by coiling a metal wire.

[0029] The outer layer 18 covers the outer periphery of the inner layer 14 and the reinforcement portion 16. The resin material constituting the outer layer 18 is not particularly limited, but may be, for example, polyether block amide (PEBA), polyethylene (PE), polypropylene (PP), polyamide (PA), polyimide (PI), polyamide-imide (PAI), polyethylene terephthalate (PET), polyurethane (PU), nylon elastomer, polyester elastomer, ethylene-vinyl acetate resin (EVA), or polyvinyl chloride (PVC). For example, Pebax® manufactured by Arkema may be used as the resin constituting the outer layer 18. The outer peripheral surface of the outer layer 18 is preferably coated with a hydrophilic material such as hyaluronic acid, polyvinylpyrrolidone (PVP), polyvinyl alcohol (PVA), or polyvinyl alkyl ether and maleic anhydride copolymer (VEMA). For example, the hydrophilic coating may be applied only to a portion of the outer layer 18 extending from the distal end P to a predetermined position in the longitudinal middle of the outer layer 18. The outer layer 18 is not limited to a single-layer tube, but may be a multi-layer tube made of the same or different materials. Furthermore, the outer layer 18 may have different hardnesses in multiple longitudinal sections. For example, if the outer layer 18 is divided into a distal tip 20 (described below), an intermediate section (the area indicated by arrow A1 in FIG. 2A), and a proximal end section (the area indicated by arrow A2 in FIG. 2A), the hardness of the resin forming the distal tip 20 can be the lowest, the hardness of the resin forming the proximal end section can be the highest, and the hardness of the resin forming the intermediate section can be intermediate between the hardness of the resins forming the distal tip 20 and the proximal end section. This makes the distal end of the outer layer 18 softer, preventing damage to blood vessels and improving blood vessel tracking. Furthermore, the hardness of the proximal end of the outer layer 18 ensures pushability. Furthermore, by making the hardness of the middle portion intermediate between that of the distal end and the proximal end, it is possible to make the middle portion less likely to break even if there is a large difference in hardness between the distal end and the proximal end.

[0030] Furthermore, the distal shaft 12 includes a distal tip 20 and a proximal marker 22 that are formed from a portion of the outer layer 18 , and a delivery amount control marker 24 that is formed from a portion of another portion of the outer layer 18 .

[0031] The distal tip 20 is formed at a portion including the distal end P of the outer layer 18. The distal tip 20 corresponds to the distal marker. In Fig. 2A, the distal tip 20 and the proximal marker 22 are shown in a sandy area. Specifically, the distal tip 20 is formed only in a proximal end vicinity portion that is within a range of a first predetermined length d1 (for example, within 1 cm) from the distal end P of the outer layer 18. The distal tip 20 is formed with radiopaque metal powder mixed in the resin, that is, it is formed in a state where radiopaque metal powder is mixed in the resin. For example, as the metal powder, bismuth trioxide (Bi2O3), tungsten (W), barium sulfate, etc. are used. By configuring the distal tip 20 in this way with radiopaque metal powder mixed in the resin of the outer layer 18, while ensuring the flexibility of the distal end portion of the distal shaft 12, the distal end position of the distal shaft 12 can be more easily recognized by the operator under fluoroscopy.

[0032] The proximal marker 22 is formed in a range of about 0.1 cm from a proximal end vicinity position that is separated from the proximal end R of the outer layer 18 by a second predetermined length d2 (for example, within 2 cm) toward the proximal end R. In Fig. 2A, the proximal end portion of the distal shaft 12 is cut with a surface inclined with respect to the longitudinal direction to form an inclined opening, making it easier to insert the therapeutic catheter. The proximal marker 22 is arranged based on the opening position of this inclined opening, making it easier to understand the insertion position of the therapeutic catheter. For this purpose, the proximal marker 22 is formed within 1 cm from the tip side position of the inclined opening so that the position of the opening can be grasped. Note that the proximal end portion of the distal shaft 12 may be configured not to be cut with an inclined surface. Similar to the distal tip 20, the proximal marker 22 also has radiopaque metal powder mixed in the resin. For example, as the metal powder, bismuth oxide (Bi), tungsten (W), barium sulfate, etc. are used. Note that the proximal marker 22 may be formed by attaching a ring-shaped radiopaque marker made of a metal such as a Pt alloy near the proximal end R of the distal shaft 12.

[0033] The marker 24 for guiding amount regulation is formed within the range of arrow B in Fig. 2A. Specifically, the marker 24 for guiding amount regulation extends longitudinally from the proximal end of the tip 20 continuously to the position S (which becomes the proximal end of the marker 24 for guiding amount regulation) where the length from the distal end P is the third predetermined length d3. If the third predetermined length d3 is, for example, 15 cm, the marker 24 for guiding amount regulation extends from the position 15 cm away from the distal end P of the outer layer 18 toward the distal end P and is formed up to the proximal end of the tip 20. The marker 24 for guiding amount regulation is formed to regulate the guiding amount from the tip of the guiding catheter 100. Similar to the tip 20, the marker 24 for guiding amount regulation has X-ray impermeable metal powder mixed in the resin. For example, as the metal powder, bismuth trioxide (Bi2O3), tungsten (W), barium sulfate, etc. are used. By forming the marker 24 for guiding amount regulation on the distal shaft 12 in this way, as will be described later, the operator can stably and easily regulate the guiding length so that the guiding length of the guide extension catheter 10 from the guiding catheter 100 does not greatly exceed the third predetermined length d3.

[0034] Furthermore, the tip 20 and the marker 24 for guiding amount regulation are visually recognized with different shades under fluoroscopy. In this case, the marker 24 for guiding amount regulation may be configured to be visually recognized with a lighter shade than the tip 20 under fluoroscopy.

[0035] Furthermore, the proximal end S of the marker 24 for guiding amount regulation is arranged at a position spaced 5 cm or more from the proximal end of the distal shaft 12 toward the distal end P side of the distal shaft 12. Thereby, as will be described later, when the operator guides the guide extension catheter 10 from the tip of the guiding catheter 100, it becomes easier to prevent all of the distal shaft 12 from being guided out from the tip of the guiding catheter 100 and the proximal end of the distal shaft 12 from being caught by the tip of the guiding catheter 100.

[0036] Figure 3 is a schematic diagram showing the formation ranges of the tip chip 20, the lead-out amount regulating marker 24, and the proximal marker 22 in the guide extension catheter 10 under fluoroscopy. For example, as shown in FIG. 3 and FIGS. 4 and 5 described later, the tip chip 20 is dark gray under fluoroscopy, and the lead-out amount regulating marker 24 is lighter gray than the tip chip 20 under fluoroscopy. Thereby, as described later, the procedure using the catheter inserted into the lumen 15, more specifically, the procedure such as the procedure using the treatment catheter inserted inside the distal shaft 12 of the guide extension catheter 10 becomes easier.

[0037] Furthermore, in a configuration where the lead-out amount regulating marker 24 is visually recognized with a lighter shade than the tip chip 20 under fluoroscopy as shown in FIG. 3, the lead-out amount regulating marker 24 and the tip chip 20 may be mixed with the same type of metal powder, and the lead-out amount regulating marker 24 may have a smaller weight ratio of the metal powder in the resin than the tip chip 20. For example, the tip chip 20 may be configured by mixing 80% by weight of tungsten (W) into polyurethane (PU), and the lead-out amount regulating marker 24 may be configured by mixing 60% by weight of tungsten (W) into polyurethane (PU). Thereby, since the same type of metal powder is used for the lead-out amount regulating marker 24 and the tip chip 20, the work of manufacturing the guide extension catheter 10 becomes easy, and since the characteristics of the lead-out amount regulating marker 24 and the tip chip 20 are likely to be close to each other, it becomes easy to process.

[0038] According to the above-described guide extension catheter 10, when the operator leads the guide extension catheter 10 from the distal end 101 (FIG. 1) of the guiding catheter 100 while viewing an X-ray radiation image, the operator can limit the lead-out length at a position where the base end S of the lead-out amount limiting marker 24 in the lead-out portion is visible. This allows the operator to stably and easily limit the lead-out length so that it does not greatly exceed the third predetermined length d3. For example, if the third predetermined length d3 is set to 15 cm, the operator can stably and easily limit the lead-out length so that the lead-out length of the guide extension catheter 10 from the guiding catheter 100 does not greatly exceed 15 cm.

[0039] FIG. 4 is a perspective view showing the guide extension catheter 10 displayed on the X-ray irradiation image display device 110. In FIG. 4 and FIG. 5 (described later), the delivery amount control marker 24 is shown as being lighter in color than the distal tip 20 under X-ray fluoroscopy. While the delivery amount control marker 24 is visualized under X-ray fluoroscopy, the portion of the guide extension catheter 10 proximal to the delivery amount control marker 24, excluding the proximal marker 22, does not contain a contrast agent and is therefore not visualized or is difficult to see. For example, if the proximal shaft 50 is made of a metal such as stainless steel, the portion is visualized but is difficult to see. In FIG. 4, the portion of the guide extension catheter 10 proximal to the delivery amount control marker 24 is shown by dashed lines, excluding the proximal marker 22, as an outline.

[0040] 5 is a display image of the X-ray irradiation image display device 110, showing the state in which the guide extension catheter 10 has been delivered from the distal end 101 of the guiding catheter 100. When the operator delivers the guide extension catheter 10 from the distal end 101 of the guiding catheter 100, it can be seen that the dark-colored distal tip 20 has been delivered first, and when the guide extension catheter 10 is delivered further, it can be seen that the delivery amount control marker 24, which is a lighter color than the distal tip 20, has been delivered. When the guide extension catheter 10 is delivered further, the base end S of the delivery amount control marker 24 is delivered from the distal end 101 of the guiding catheter 100, as shown in FIG. 5, and it can be seen that a non-contrast-enhanced portion has been delivered. This allows the operator to slightly return the delivery portion to the guiding catheter 100 and align the position of the base end S of the delivery amount control marker 24 with the tip 101 of the guiding catheter 100, thereby regulating the delivery length of the guide extension catheter 10 to a third predetermined length d3 (Figures 2A and 3) (e.g., 15 cm).

[0041] Furthermore, the distal tip 20 and the derived amount regulating marker 24 are visible under X-ray fluoroscopy in different shades, making it easier for the operator to recognize the position of the distal end P of the guide extension catheter 10 under X-ray fluoroscopy.

[0042] Furthermore, with the configuration in which the derived amount control marker 24 is visible under X-ray fluoroscopy as it appears lighter in shade than the distal tip 20, it is possible to make the radiopaque markers of the treatment catheter or diagnostic catheter inserted inside the distal shaft 12 of the guide extension catheter 10 visible under X-ray fluoroscopy even in the portion where the derived amount control marker 24 is provided. This allows the operator to always check under X-ray fluoroscopy the position of the radiopaque marker of the catheter inserted inside the distal shaft 12 of the guide extension catheter 10, making it possible to perform the procedure with precision without losing sight of the radiopaque marker.

[0043] Furthermore, the proximal end S of the lead amount regulating marker 24 is disposed at a position spaced 5 cm or more from the proximal end of the distal shaft 12 and on the distal end P side of the distal shaft 12. Thereby, when the operator guides the guide extension catheter 10 from the tip of the guiding catheter 100 while viewing the X-ray irradiation image, if the lead length is restricted at the position where the proximal end S of the lead amount regulating marker 24 at the leading portion is visible, the length from the proximal end S of the leading portion to the proximal end of the distal shaft 12 disposed in the guiding catheter 100 can be sufficiently ensured. As a result, it is easy to prevent all of the distal shaft 12 from being led out from the tip of the guiding catheter 100 and the proximal end of the distal shaft 12 from being caught on the tip of the guiding catheter 100.

[0044] FIG. 6 is a schematic view showing the formation ranges of the tip chip 20, the lead amount regulating marker 24a, and the hand marker 22 under fluoroscopy in a guide extension catheter 10a according to another example of the embodiment. In the case of this example, the lead amount regulating marker 24a is separated from the tip chip 20. Specifically, the lead amount regulating marker 24a extends from a position spaced longitudinally from the proximal end of the tip chip 20 toward the proximal end side of the distal shaft 12, and the proximal end S is at a position where the length from the distal end P of the distal shaft 12 is a third predetermined length d3.

[0045] Even when using the guide extension catheter 10a of this example, similar to the configurations of FIGS. 1 to 5, when the operator derives the guide extension catheter 10a from the tip 101 (FIG. 1) of the guiding catheter 100 while viewing the X-ray irradiation image, the derivation length can be restricted at the position where the proximal end S of the derivation amount restricting marker 24 at the derivation portion is visible. Thereby, the derivation length can be stably and easily restricted so that the derivation length does not greatly exceed the third predetermined length d3. Further, since the tip chip 20 and the derivation amount restricting marker 24 are visually recognized with different shades under X-ray fluoroscopy, the operator can more easily recognize the position of the distal end P of the guide extension catheter 10a under X-ray fluoroscopy. Further, since the tip chip 20 and the derivation amount restricting marker 24 are arranged at an interval, the X-ray impermeable marker of the treatment catheter or the diagnostic catheter inserted inside the distal shaft 12 of the guide extension catheter 10a can be clearly visible under X-ray fluoroscopy at the portion corresponding to the above interval. Thereby, the position of the X-ray impermeable marker of the catheter inserted inside the distal shaft 12 of the guide extension catheter 10a becomes easier for the operator to see under X-ray fluoroscopy. In this example, the other configurations and operations are the same as those of the configurations of FIGS. 1 to 5.

[0046] FIG. 7 is a schematic diagram showing the formation ranges of the delivery amount control marker 24b and the proximal marker 22 under X-ray fluoroscopy in a guide extension catheter 10b according to another embodiment. In this example, in the configuration shown in FIGS. 1 to 5, the distal tip 20 and the delivery amount control marker 24b have the same density under X-ray fluoroscopy. In other words, the distal end of the delivery amount control marker 24b functions as the distal tip. The delivery amount control marker 24b extends from a predetermined longitudinal position toward the distal end P of the distal shaft 12, and the length from the base end S of the delivery amount control marker 24b to the distal end P of the distal shaft 12, i.e., the length of the delivery amount control marker 24b itself, is the third predetermined length d3. The third predetermined length d3 is preferably 10 to 20 cm, and more preferably 15 cm. As with the above examples, the guide extension catheter 10b of this example also makes it possible to stably and easily regulate the extension length of the guide extension catheter 10b from the guiding catheter 100 so that it does not greatly exceed the third predetermined length d3. Furthermore, since the number of markers can be reduced compared to the above examples, confusion on the part of the operator can be reduced, unlike when a large number of markers are used. In this example, the other configurations and functions are the same as those of FIGS. 1 to 5. [Explanation of symbols]

[0047] 10, 10a, 10b guide extension catheter, 12 distal shaft, 14 inner layer, 15 lumen, 16 reinforced portion, 18 outer layer, 20 distal tip, 22 hand marker, 24 marker for regulating delivery amount, 50 proximal shaft, 100 guiding catheter, 101 tip, 102 coronary artery, 106 stent delivery catheter, 107 stent, 110 X-ray irradiation image display device.

Claims

1. a cylindrical distal shaft; and a proximal shaft made of a metal wire connected to a proximal end of the distal shaft; The distal shaft a tip marker formed continuously in the longitudinal direction from the distal end and made of resin containing metal powder; a hand marker provided at the proximal end, which is formed by mixing radiopaque metal powder into resin or by attaching a metal ring; a delivery amount control marker for controlling the amount of delivery from the guiding catheter, the delivery amount control marker extending continuously in the longitudinal direction from the base end of the tip marker and having its base end at a position where the length from the distal end of the distal shaft is a predetermined length, the delivery amount control marker being made of resin containing metal powder; The derived amount regulating marker is visually recognized under X-ray fluoroscopy as being lighter in shade than the tip marker, and In the distal shaft, the shade between the derived amount regulating marker and the hand marker is visually recognized as being lighter than the shade between the derived amount regulating marker and the hand marker under X-ray fluoroscopy. Guide extension catheter.

2. The guide extension catheter according to claim 1, The lead-out amount regulating marker and the tip marker are mixed with the same type of metal powder, The delivery amount control marker has a smaller weight ratio of metal powder in resin than the tip marker. Guide extension catheter.

3. The guide extension catheter according to claim 1 or 2, The predetermined length is 15 cm. Guide extension catheter.

4. The guide extension catheter according to any one of claims 1 to 3, The base end of the delivery amount control marker is disposed at a position spaced apart from the proximal end of the distal shaft by at least 5 cm toward the distal end of the distal shaft. Guide extension catheter.

Images