JP2019176978A - Medical long body, medical device, and medical method - Google Patents

Abstract

To provide a medical long body, a medical device, and a medical method in a technique of assisting delivery of a catheter in a living body lumen using a medical long body having an expansion member, in which insertion resistance of the catheter to the living body lumen can be reduced, and positional deviation of the expansion member to the catheter can be prevented.SOLUTION: An expansion member 140 of a medical long body 100 comprises: a tip taper part 143; a base end taper part 145; and an intermediate part 146 arranged between the tip taper part 143 and the base end taper part 145. The expansion member is configured so that when it is expanded, a maximum outer diameter part 143a of the tip taper part becomes larger than a maximum outer diameter part 146a of the intermediate part and a maximum outer diameter part 145a of the base end taper part, an outer surface of the intermediate part has a friction coefficient higher than that of an outer surface of the tip taper part.SELECTED DRAWING: Figure 7

Description

  The present invention relates to a medical elongated body, a medical instrument, and a medical method.

  In the medical field, a minimally invasive treatment method is recommended. For example, a technique such as TRI (Trans Radial Intervention) for inserting a medical instrument from a radial artery running on an arm is known. In a procedure such as TRI, a treatment device is inserted through a thin blood vessel such as a radial artery, so the sheath and guide catheter that guides the treatment device into the blood vessel have a product specification with a large inner diameter and a smaller outer diameter. It is hoped that.

  In a procedure such as general PCI, a guide catheter is inserted into a blood vessel through a sheath inserted into the blood vessel prior to the guide catheter (see, for example, Patent Document 1). Therefore, an operator such as a doctor has to select a guide catheter having an outer diameter that can be inserted into the lumen of the sheath as a guide catheter used for the procedure. As a result, the types of guide catheters that can be selected by the operator are narrowed depending on the thickness of the sheath, which may limit the procedures that can be performed.

  In consideration of the above problems, for example, an operator may employ a sheathless PCI in which a guide catheter is inserted into a blood vessel without using a sheath. In the sheathless PCI, when the guide catheter is inserted into the blood vessel, the outer diameter of the guide catheter can be increased by an amount corresponding to the thickness of the sheath. Therefore, the operator can insert a larger treatment device into the blood vessel via the guide catheter by adopting sheathless PCI.

  As one method for realizing sheathless PCI, a so-called BAT (Ballon Assist Technique) using a medical long body including a balloon (expansion member) is known.

  For example, in sheathless PCI, when an operator inserts a guide catheter into a blood vessel without using a sheath, the distal end forming the distal end opening of the guide catheter comes into contact with the puncture portion or the blood vessel wall. There is a possibility that the insertion resistance into the blood vessel is increased. In order to improve such a problem, an operator may use a medical long body including a balloon and use the BAT. Specifically, in BAT, the operator inserts a balloon into the guide catheter, and causes the tip tapered portion of the balloon to protrude from the tip opening of the guide catheter. Next, the operator expands the balloon so that the tip tapered portion of the balloon covers the tip of the guide catheter from the tip side of the guide catheter. Thus, when the operator inserts the guide catheter into the blood vessel, the surgeon reduces the gap formed between the outer diameter of the distal end of the guide catheter and the outer diameter of the medical elongated body, and the guide catheter is inserted into the blood vessel. The insertion resistance can be reduced.

JP2015-213682A

  However, the following problems may occur in the procedure using BAT. As described above, when the guide catheter is delivered by a blood vessel, the medical long body including the balloon is assembled to the guide catheter in a state where the balloon is expanded. When delivering the guide catheter to a target site in the blood vessel, the operator operates to push the guide catheter in vitro. At this time, the balloon slips with respect to the inner wall of the guide catheter, and the position of the balloon relative to the guide catheter may be displaced. In such a case, there is a gap between the outer diameter of the tip of the guide catheter and the outer diameter of the balloon, a gap between the tip of the guide catheter and the balloon, or a step between the balloon and the guide catheter. Will be formed. Therefore, due to the step between the balloon and the guide catheter, an assembly formed by the medical long body including the balloon and the guide catheter has a reduced ability to pass through the blood vessel.

  The present invention has been made in view of the above problems, and in a technique for assisting delivery of a catheter in a living body lumen using a medical elongated body including an expansion member, the insertion resistance of the catheter into the living body lumen is reduced. An object of the present invention is to provide a medical elongated body, a medical instrument, and a medical method that can be reduced in size and can prevent the expansion member from being displaced from the catheter.

  The elongated medical body of the present invention includes an inner tube shaft having a lumen through which a guide wire can be inserted, an outer tube shaft disposed so as to cover a part of the inner tube shaft, and a distal end of the inner tube shaft And an expansion member disposed at a distal end portion of the outer tube shaft, and the expansion member is disposed between a distal taper portion, a proximal taper portion, and the distal taper portion and the proximal taper portion. And the expansion member is configured such that when the expansion member expands, the maximum outer diameter portion of the tip tapered portion is the maximum outer diameter portion of the intermediate portion and the proximal taper portion. It is configured to be larger than the maximum outer diameter portion, and the outer surface of the intermediate portion has a higher coefficient of friction than the outer surface of the tip tapered portion.

  The medical instrument of the present invention includes an inner tube shaft having a lumen through which a guide wire can be inserted, an outer tube shaft arranged to cover a part of the inner tube shaft, and a distal end portion of the inner tube shaft. And an expansion member disposed at the distal end portion of the outer tube shaft, and an outer catheter having a lumen into which the inner catheter can be inserted. And a proximal end taper portion, and an intermediate portion disposed between the distal end taper portion and the proximal end taper portion, and the expansion member expands when the expansion member is expanded. The maximum outer diameter portion of the intermediate portion is configured to be larger than the maximum outer diameter portion of the intermediate portion, the maximum outer diameter portion of the proximal tapered portion, and the inner diameter of the outer catheter, and the outer surface of the intermediate portion The tip Coefficient of friction than the outer surface of the par portion is high, wherein the.

  Further, the medical method of the present invention includes an inner tube shaft having a lumen through which a guide wire can be inserted, an outer tube shaft disposed so as to cover a part of the inner tube shaft, and a distal end portion of the inner tube shaft And an expansion member disposed at the distal end portion of the outer tube shaft, and an outer catheter having a lumen into which the inner catheter can be inserted. A proximal tapered portion, and an intermediate portion disposed between the distal tapered portion and the proximal tapered portion, the inner catheter is inserted into the lumen of the outer catheter, With the portion protruding from the distal end of the outer catheter, the expansion member is expanded with a first internal pressure, and the maximum outer diameter portion of the distal tapered portion of the expansion member contacts the distal end portion of the outer catheter. The inner catheter is moved in such a manner that the expansion member is expanded at a second internal pressure larger than the first internal pressure to form an assembly of the outer catheter and the inner catheter, and percutaneously into the living body lumen. Insert the assembly.

  When the expansion member is expanded in a state where a part of the expansion member protrudes from the distal end of the catheter, the distal end portion of the expansion member covers the distal end of the catheter from the distal end side of the catheter. For this reason, the medical elongated body is configured such that the assembly of the medical elongated body and the catheter is placed in the body lumen in a state where the tip tapered portion of the expansion member fills the step formed on the outer surface of the catheter and the outer surface of the expansion member. Allows to be inserted into. Accordingly, the assembly in which the medical elongated body and the catheter are combined can prevent the tip of the catheter from being caught on the puncture portion and the inner wall of the biological lumen when the assembly is inserted into the biological lumen. it can. Thereby, the medical elongated body can reduce the insertion resistance of the assembly into the living body lumen. Further, since the expansion member has a higher frictional resistance at the intermediate portion than the tapered end portion, the expansion member can be prevented from being displaced with respect to the catheter in a state where the assembly is formed. Thereby, the medical elongated body can improve the passage through the living body lumen in a state where the assembly is formed.

  In the above-described medical device, when the expansion member expands with a part of the expansion member protruding from the distal end of the catheter, the distal end portion of the expansion member covers the distal end of the catheter from the distal end side of the catheter. Therefore, the medical instrument enables the assembly to be inserted into the living body lumen in a state in which the tip taper portion of the expansion member fills the step formed on the outer surface of the catheter and the outer surface of the expansion member. Accordingly, the assembly in which the medical elongated body and the catheter are combined can prevent the tip of the catheter from being caught on the puncture portion and the inner wall of the biological lumen when the assembly is inserted into the biological lumen. it can. Thereby, the medical instrument can reduce the insertion resistance of the assembly into the living body lumen. Further, since the expansion member has a higher frictional resistance at the intermediate portion than the tapered end portion, the expansion member can be prevented from being displaced with respect to the catheter in a state where the assembly is formed. As a result, the medical instrument is improved in passage through the living body lumen in a state where the assembly is formed.

  In the medical method, the expansion member is expanded with the first internal pressure in a state where a part of the expansion member included in the inner catheter protrudes from the distal end of the outer catheter. Then, in the medical method, the inner catheter is moved so that the maximum outer diameter portion of the distal end tapered portion of the expansion member is in contact with the distal end portion of the outer catheter. Thereby, the medical method can arrange | position the front end taper part of an expansion member to the front end side of an outer catheter easily. In the medical method, when the expansion member is expanded with the second internal pressure, the distal end portion of the expansion member can cover the distal end of the outer catheter from the distal end side of the outer catheter. Therefore, in the medical method, the assembly can be inserted into the living body lumen in a state where the tip tapered portion of the expansion member fills the step formed on the outer surface of the outer catheter and the outer surface of the expansion member. Thereby, the medical method can reduce the insertion resistance of the assembly into the living body lumen.

It is a figure which shows simply the medical device which concerns on embodiment. It is an expanded sectional view of the front-end | tip part of the inner side catheter (medical elongate body) which concerns on embodiment. It is an expanded sectional view of the front-end | tip part of the outer catheter which concerns on embodiment. It is an expanded sectional view showing a part of tip part of an inner catheter concerning an embodiment. It is sectional drawing for demonstrating the medical method which concerns on embodiment, and is a figure which shows a mode at the time of expanding an expansion member with 1st internal pressure. It is sectional drawing for demonstrating the medical method which concerns on embodiment, and is a figure which shows a mode at the time of moving the expansion member of the state expanded by the 1st internal pressure to the base end side. It is sectional drawing for demonstrating the medical method which concerns on embodiment, and is a figure which shows a mode at the time of expanding an expansion member with a 2nd internal pressure. It is sectional drawing for demonstrating the medical method which concerns on embodiment, and is a figure which shows a mode at the time of contracting an expansion member so that it may become a 3rd internal pressure. It is a figure which shows simply a mode when the front-end | tip curved part of an outer side catheter is deform | transformed by the expansion member in substantially linear form.

  Embodiments of the present invention will be described below with reference to the drawings. In addition, the dimension ratio of drawing is exaggerated on account of description, and may differ from an actual ratio.

<Medical device>
FIG. 1 shows a medical instrument 10 according to this embodiment.

  The medical instrument 10 includes an inner catheter (corresponding to a “medical elongated body”) 100 and an outer catheter 200. The inner catheter 100 is constituted by a balloon catheter including an expansion member 140 made of a balloon. The outer catheter 200 is configured by a guide catheter that can be used for delivery of a medical device or the like.

  As illustrated in FIG. 7, the medical device 10 forms an assembly 10A in which the inner catheter 100 and the outer catheter 200 are combined when the inner catheter 100 and the outer catheter 200 are inserted into a biological lumen such as a blood vessel. The assembly 10A can be used in a so-called BAT (Ballon Assist Technique) procedure.

  Hereinafter, in the description of the specification, the side of the catheters 100 and 200 to be introduced into the living body is referred to as “distal side”, the side on which the hubs 160 and 260 are disposed is referred to as “proximal side”, and the shaft 110 and The direction (the left-right direction in FIGS. 2 and 3) in which the main body 210 extends is referred to as the “axial direction”. 2 to 8 are sectional views (longitudinal sectional views) along the axial direction of the distal ends of the catheters 100 and 200. FIG. Further, in this specification, the “tip portion” means a certain range in the axial direction including the tip (the most distal end), and the “base end portion” means the axial direction including the base end (the most proximal end). Means a certain range.

<Inner catheter>
As shown in FIG. 1, the inner catheter 100 includes an elongate shaft 110, an expansion member 140 disposed at the distal end portion of the shaft 110, and a hub 160 disposed at the proximal end portion side of the shaft 110. Have.

  As shown in FIGS. 2 and 4, the shaft 110 includes an inner tube shaft 120 having a lumen 125 through which the guide wire 300 can be inserted, and an outer tube shaft 130 disposed so as to cover a part of the inner tube shaft 120. And have.

  The inner tube shaft 120 and the outer tube shaft 130 are fused at a predetermined portion in the axial direction of the shaft 110. As shown in FIG. 1, the shaft 110 is provided with a guide wire port 115 communicating with the lumen 125 of the inner tube shaft 120.

  The inner catheter 100 is configured as a rapid exchange type catheter. However, the inner catheter 100 may be an over-the-wire type catheter.

  As shown in FIG. 4, the inner tube shaft 120 includes a first region 126 and a second region 127 having a color different from that of the first region 126. The first region 126 of the inner tube shaft 120 is formed at a position corresponding to the tip tapered portion 143 of the expansion member 140 in the inner tube shaft 120. The “corresponding position” means that the distal end of the distal tapered portion 143 and the distal end of the first region 126 overlap at least in the circumferential direction of the inner tube shaft 120 and the proximal end (maximum outer diameter portion) of the distal tapered portion 143. 143a and the base end of the first region 126 at least overlap each other in the circumferential direction of the inner tube shaft 120.

  The second region 127 of the inner tube shaft 120 can be formed so as to extend to the vicinity of the proximal end portion of the inner tube shaft 120, for example.

  The method (coloring method) for forming the first region 126 of the inner tube shaft 120 is not particularly limited, and a known method can be adopted. As an example, a method of including a predetermined color pigment in the constituent material of the inner tube shaft 120 can be cited. The colors of the first region 126 and the second region 127 are not particularly limited, and any color can be selected. Further, in the present embodiment, the expansion member 140 is preferably configured to be transparent or translucent, for example, so that the first region 126 of the inner tube shaft 120 can be confirmed from the outside.

  As shown in FIG. 2, the inner lumen 135 of the outer tube shaft 130 communicates with the inner space 147 of the expansion member 140. A pressure medium can be circulated through the inner lumen 135 of the outer tube shaft 130. The supply of the pressurized medium to the internal space 147 of the expansion member 140 and the discharge of the pressurized medium from the internal space 147 of the expansion member 140 are performed by a known fluid supply device (for example, an indeflator) connected to the hub 160. Can be used. In addition, the kind of pressurization medium is not specifically limited.

  As shown in FIG. 2, the expansion member 140 is disposed at the distal end portion 121 of the inner tube shaft 120 and the distal end portion 131 of the outer tube shaft 130. The distal end portion 141 of the expansion member 140 is fixed to the distal end portion 121 of the inner tube shaft 120. A proximal end portion 142 of the expansion member 140 is fixed to the distal end portion 131 of the outer tube shaft 130.

  As shown in FIGS. 2 and 4, the expansion member 140 includes a distal tapered portion 143, a proximal tapered portion 145, an intermediate portion 146 disposed between the distal tapered portion 143 and the proximal tapered portion 145, have.

  As shown in FIG. 4, when the expansion member 140 is expanded, the expansion member 140 has a maximum outer diameter portion 143a of the distal end taper portion 143 that is a maximum outer diameter portion 146a of the intermediate portion 146 and a maximum outer diameter portion of the proximal end taper portion 145. It is comprised so that it may become larger than the diameter part 145a. In this specification, “when the expansion member expands” means that the expansion member 140 is expanded at a nominal pressure (for example, 6 atm) unless otherwise specified. 2, 4, and 7 are cross-sectional views of the expansion member 140 when expanded with a nominal pressure.

  In addition, when the expansion member 140 is expanded, as shown in FIG. 7, the expansion member 140 has a maximum outer diameter portion 143a of the tip tapered portion 143 that is larger than the inner diameter of the outer catheter 200 (the inner diameter of the main body portion 210) described later. It is configured to be large.

  As shown in FIG. 4, the maximum outer diameter portion 143 a of the distal tapered portion 143 is located at the proximal end of the distal tapered portion 143. The maximum outer diameter portion 143a of the tip tapered portion 143 is located at a boundary portion (a position indicated by a one-dot chain line b1 in FIG. 4) between the tip tapered portion 143 and a stepped portion 144 described later.

  As shown in FIG. 4, the maximum outer diameter portion 145 a of the proximal end tapered portion 145 is located at the distal end of the proximal end tapered portion 145. Further, the maximum outer diameter portion 145a of the base end taper portion 145 is located at a boundary portion (a position indicated by an alternate long and short dash line b3 in FIG. 4) between the base end taper portion 145 and the intermediate portion 146.

  As shown in FIG. 4, the intermediate portion 146 forms a straight portion in which each portion of the intermediate portion 146 in the axial direction of the expansion member 140 has a substantially constant outer diameter when the expansion member 140 is expanded. Therefore, the maximum outer diameter portion 146 a of the intermediate portion 146 in the expansion member 140 can be defined at an arbitrary position in the intermediate portion 146.

  In the present embodiment, when the expansion member 140 is expanded, the outer diameter of the maximum outer diameter portion 145a of the base end tapered portion 145 and the outer diameter of the maximum outer diameter portion 146a of the intermediate portion 146 are substantially the same.

  When the expansion member 140 is expanded and deformed, it forms a first expanded state and a second expanded state in which the maximum outer diameter portion 146a of the intermediate portion 146 is larger than that in the first expanded state. 5 and 6 show the expansion member 140 in the first expanded state, and FIG. 7 shows the expansion member 140 in the second expanded state.

  In the first expanded state, the expansion member 140 has a maximum outer diameter portion 146a of the intermediate portion 146 smaller than an inner diameter of the outer catheter 200 and a maximum outer diameter of the distal tapered portion 143 as shown in FIGS. The diameter portion 143a is larger than the inner diameter of the outer catheter 200.

  The first expanded state is a state in which the expansion member 140 is expanded at, for example, 2 to 4 atm (the first internal pressure). The second expanded state is a state in which the expansion member 140 is expanded at, for example, 6 atm (second internal pressure, the nominal pressure of the present embodiment). In the second expanded state, the expansion member 140 has a maximum outer diameter of the intermediate portion 146 such that the maximum outer diameter portion 146a of the intermediate portion 146 contacts the inner surface of the outer catheter 200, as shown in FIG. The portion 146a is larger than the inner diameter of the outer catheter 200. Further, as will be described later, when the inner catheter 100 is removed from the lumen 215 of the outer catheter 200, the expansion member 140 is contracted to have a third internal pressure lower than the first internal pressure (see FIG. 8). .

  The axial length d3 of the intermediate portion 146 of the expansion member 140 is longer than the axial length d1 of the portion of the distal end member 240 of the outer catheter 200, which will be described later, that protrudes more distally than the main body portion 210 (FIG. 3). And see FIG.

  The axial length d3 of the intermediate portion 146 of the expansion member 140 is equal to the axial length d1 of the portion of the distal end member 240 of the outer catheter 200 that protrudes more distally than the main body portion 210 and the first length of the main body portion 210. It is longer than the value obtained by adding the axial length d2 of one region 216 (see FIGS. 3 and 4). In addition, the specific numerical value of each said dimension d1, d2, d3 is not specifically limited.

  The expansion member 140 can be configured such that the maximum outer diameter portion 143a of the tip tapered portion 143 is, for example, 1.4 mm to 3.0 mm when the expansion member 140 is expanded with a nominal pressure. In addition, the expansion member 140 can be configured such that the maximum outer diameter portion 145a of the base end taper portion 145 is, for example, 1.25 mm to 2.75 mm when the expansion member 140 is expanded with a nominal pressure. Further, the expansion member 140 can be configured such that the maximum outer diameter portion 146a of the intermediate portion 146 is, for example, 1.25 mm to 2.5 mm when the expansion member 140 is expanded with a nominal pressure. The above dimensions are dimensions that do not include the thicknesses of the first covering portion 151 and the second covering portion 152.

  As shown in FIG. 4, when the expansion member 140 is expanded, the maximum outer diameter portion 143a of the tip tapered portion 143 (the position indicated by the one-dot chain line b1 in FIG. 4) and the tip 146b of the intermediate portion 146 (the one-dot chain line in FIG. 4). A stepped portion 144 is provided between the positions indicated by b2.

  The stepped portion 144 has a curved portion 144a that is curved from the tip tapered portion 143 side toward the intermediate portion 146 side, and a vertical wall portion 144b that extends substantially perpendicularly in the radial direction on the proximal end side of the curved portion 144a. Yes.

  Note that the cross-sectional shape of the stepped portion 144 is not limited to the shape shown in FIG. The stepped portion 144 has, for example, a cross-sectional shape that is inclined obliquely from the tip tapered portion 143 side to the intermediate portion 146 side, or is curved or bent between the tip tapered portion 143 and the intermediate portion 146 a plurality of times. It may have a shape like that.

  The expansion member 140 according to the present embodiment is configured such that the outer surface of the intermediate portion 146 has a higher friction coefficient than the outer surface of the tip tapered portion 143.

  As shown in FIG. 4, a first covering portion 151 having a lower coefficient of friction than the outer surface of the intermediate portion 146 is disposed on the outer surface of the tip tapered portion 143. The first covering portion 151 is disposed so as to cover at least the stepped portion 144.

  A hydrophobic second covering portion 152 having a higher coefficient of friction than the constituent material of the expansion member 140 is disposed on at least a part of the outer surface of the intermediate portion 146. The proximal end of the second covering portion 152 is disposed at the proximal end of the intermediate portion 146. Note that the base end of the second covering portion 152 can be disposed on the base end tapered portion 145 so that the second covering portion 152 covers the base end tapered portion 145.

  The first covering portion 151 is composed of a hydrophilic covering portion having a lower friction coefficient than the second covering portion 152. Further, the first covering portion 151 is also disposed in a part of the intermediate portion 146 located on the proximal end side with respect to the stepped portion 144.

  The outer surface of the intermediate portion 146 of the expansion member 140 has a region formed with a higher coefficient of friction than the inner surface that forms the lumen of the outer catheter 200 (the lumen 215 of the main body 210), which will be described later. In the present embodiment, the region where the second covering portion 152 of the intermediate portion 146 is formed has a higher coefficient of friction than the inner surface that forms the lumen 215 of the outer catheter 200.

  As shown in FIGS. 2 and 4, the inner tube shaft 120 has a tip member 180 that is more flexible than the inner tube shaft 120. The tip member 180 has a lumen 181 through which the guide wire 300 can be inserted. The tip member 180 is disposed at the tip of the inner tube shaft 120. The inner tube shaft 120 is provided with the distal end member 180 on the distal end side, whereby damage to the living organ can be prevented when the distal end of the inner catheter 100 comes into contact with the living body lumen (such as the inner wall of the blood vessel). The constituent material of the tip member 180 is not particularly limited as long as it is more flexible than the inner tube shaft 120 and can be fixed to the inner tube shaft 120.

  As shown in FIG. 4, the inner tube shaft 120 includes a contrast marker 171 that indicates the position of the maximum outer diameter portion 143 a of the distal end tapered portion 143 (the proximal end of the distal end tapered portion 143), and the maximum outer diameter of the proximal end tapered portion 145. And a contrast marker 172 indicating the position of the portion 145a (the base end of the intermediate portion 146). The distal end of the contrast marker 171 is disposed at the maximum outer diameter portion 143 a of the distal end tapered portion 143. The proximal end of the contrast marker 172 is disposed at the maximum outer diameter portion 145 a of the proximal tapered portion 145. Each of the contrast markers 171 and 172 can be formed of, for example, a metal such as platinum, gold, silver, iridium, titanium, tungsten, or an alloy thereof.

  Each constituent material of the inner catheter 100 will be described.

  The expansion member 140 is, for example, polyethylene, polypropylene, polyolefin of ethylene-propylene copolymer, polyester such as polyethylene terephthalate, polyvinyl chloride, ethylene-vinyl acetate copolymer, cross-linked ethylene-vinyl acetate copolymer, polyurethane, etc. These thermoplastic resins, polyamides, polyamide elastomers, polystyrene elastomers and the like can be used.

  The inner tube shaft 120 and the outer tube shaft 130 are made of, for example, polyolefins such as polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, thermoplastic resins such as soft polyvinyl chloride, polyurethane elastomer, polyamide elastomer. , Various elastomers such as polyester elastomer, crystalline plastics such as polyamide, crystalline polyethylene, crystalline polypropylene, and fluorine resins such as PTFE (polytetrafluoroethylene) and PFA (tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer) Or the like.

  The first cover 151 includes, for example, an acrylamide polymer material (for example, a polyacrylamide, polyglycidyl methacrylate-dimethylacrylamide (PGMA-DMAA) block copolymer), a cellulose polymer material, and a polyethylene oxide polymer material. And a maleic anhydride polymer material (for example, a maleic anhydride copolymer such as methyl vinyl ether-maleic anhydride copolymer), a hydrophilic coating material such as water-soluble nylon, polyvinyl alcohol, and polyvinylpyrrolidone. be able to.

  The second covering portion 152 can be made of a hydrophobic covering material having a higher coefficient of friction than the constituent material of the expansion member 140. The second covering portion 152 can be made of, for example, reactive curable silicone, polytetrafluoroethylene (PTFE), fluorinated ethylene propylene (FEP), or the like.

<Outside catheter>
As shown in FIGS. 1 and 3, the outer catheter 200 includes a long main body 210 in which a lumen 215 into which the inner catheter 100 can be inserted is formed, and a hub disposed at the proximal end of the main body 210. 260, and a kink protector 250 disposed in the vicinity of the connecting portion between the main body 210 and the hub 260.

  When a surgeon performs a procedure using the medical device 10, the inner catheter 100 is inserted into the lumen 215 of the hub 260 and the main body 210 via a proximal port (not shown) provided on the hub 260 of the outer catheter 200. Insert.

  As shown in FIG. 3, the main body 210 is formed of a hollow tubular member having flexibility. The main body part 210 includes an inner layer 220, an outer layer 230 disposed so as to cover the outer surface of the inner layer 220, and a reinforcing body 218 disposed on the outer surface side of the inner layer 220.

  As shown in FIG. 3, the outer catheter 200 includes a distal end member 240 that is disposed on the distal end side of the main body 210 and is more flexible than the main body 210. In the main body part 210, the tip of the inner layer 220 protrudes further toward the tip than the tip of the outer layer 230. The tip member 240 is disposed so as to cover the outer peripheral surface of the tip of the inner layer 220 protruding from the tip of the outer layer 230.

  The tip member 240 has a lumen 241 through which the shaft 110 of the inner catheter 100 can be inserted. The main body 210 is provided with the distal end member 240 on the front end side, whereby damage to the living organ can be prevented when the front end of the main body 210 comes into contact with a living body lumen (such as the inner wall of a blood vessel). The constituent material of the tip member 240 is not particularly limited as long as the material is more flexible than the main body 210 and can be fixed to the main body 210.

  As shown in FIG. 3, the main body portion 210 of the outer catheter 200 includes a first region 216 and a second region 217 in which the reinforcing body 218 is disposed while being disposed on the proximal side of the first region 216. Have.

  As shown in FIG. 1, a distal end side curved portion 219 that is curved with respect to the axial direction of the main body portion 210 is formed at the distal end portion of the main body portion 210 of the outer catheter 200. Prior to the use of the outer catheter 200, the distal side bending portion 219 is pre-shaped on the main body 210. The distal side bending portion 219 is a bending portion formed in a range of about 0.1 to 40 mm from the most distal end of the main body portion 210 of the outer catheter 200, and the specific shape is not particularly limited.

  The main body 210 has a distal-side bending portion 219 in a natural state where no external force is applied to the main body 210 or in a state where the inner catheter 100 is inserted through the main body 210 and the expansion member 140 is not expanded. Further, as shown in FIG. 9, the distal-side bending portion 219 of the main body 210 is in a state where the intermediate portion 146 of the expansion member 140 is disposed at a position including the proximal end side with respect to the proximal end 219 a of the distal-end bending portion 219. Thus, when the expansion member 140 expands, the expansion member 140 is deformed in a substantially linear shape with respect to the axial direction. That is, when the expansion member 140 expands in a state where the expansion member 140 is inserted through the main body portion 210, the main body portion 210 is deformed from a state having the distal end side bending portion 219 to a state not having the distal end side bending portion 219. . In FIG. 9, a state in which the distal end side bending portion 219 is formed on the main body 210 is indicated by a two-dot chain line, and a state in which the main body 210 is deformed in a substantially linear shape is indicated by a solid line.

  The inner diameter of the main body 210 of the outer catheter 200 can be formed to be 1.25 mm to 2.5 mm, for example. Moreover, the outer diameter of the main-body part 210 of the outer catheter 200 can be formed in 1.4 mm-2.9 mm, for example.

  Each constituent material of the outer catheter 200 will be described.

  The inner layer 220 of the main body 210 is made of, for example, a fluorine-based resin such as PTFE (polytetrafluoroethylene) or PFA (tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer), polyethylene, polypropylene, ethylene-propylene copolymer, ethylene. -It can be composed of polyolefin such as vinyl acetate copolymer, polyamide, polyamide elastomer and the like.

  The outer layer 230 of the main body 210 can be composed of various elastomers such as polyamide elastomer, polyester elastomer, polyurethane elastomer, polystyrene elastomer, silicone rubber, latex rubber, and the like.

  As the reinforcing body 218, for example, a metal strand, a resin strand, or a combination of a metal strand and a resin strand can be used. The structure of the reinforcing body 218 is, for example, a 1 over 1 under structure in which the strands alternately cross each other, or a 2 over 2 under structure in which the strands intersect every 2 times, or a plurality of sets are knitted as a set. Such a structure or a combination of these can be employed.

  Next, a medical method using the medical instrument 10 including the inner catheter 100 and the outer catheter 200 will be described.

  In summary, the medical method according to this embodiment is formed by combining the inner catheter 100 and the outer catheter 200 to form an assembly 10A, inserting the assembly 10A into a living body lumen (for example, a blood vessel), and inserting the assembly 10A into a living body. To the desired position, releasing the state in which the assembly 10A is formed, and removing the inner catheter 100 from the outer catheter 200.

  First, the operator prepares the inner catheter 100 and the outer catheter 200. Next, the surgeon inserts the inner catheter 100 into the lumen 215 of the main body 210 of the outer catheter 200. At this time, the operator inserts the inner catheter 100 into the lumen 215 of the main body portion 210 of the outer catheter 200 in an unexpanded state (a state in which the internal pressure of the expanding member 140 is not increased). To do.

  Next, as shown in FIG. 5, the surgeon moves a part of the expansion member 140 (a range including a part of the tip tapered part 143 and a part of the intermediate part 146) from the tip of the outer catheter 200 (tip of the tip member 240). In the protruding state, the expansion member 140 is expanded with the first internal pressure. By expanding the expansion member 140 with the first internal pressure, the maximum outer diameter portion 146a of the intermediate portion 146 is smaller than the inner diameter of the main body portion 210 of the outer catheter 200, and the maximum outer diameter portion 143a of the distal tapered portion 143 is reduced. It deform | transforms into the 1st expansion state larger than the internal diameter of the main-body part 210 of the outer catheter 200. FIG.

  Next, as shown in FIG. 6, the surgeon sets the inner catheter so that the maximum outer diameter portion 143 a of the distal end tapered portion 143 of the expansion member 140 contacts the distal end portion of the outer catheter 200 (the distal end portion of the distal end member 240). 100 is moved to the proximal side. At this time, since the maximum outer diameter portion 146a of the intermediate portion 146 of the expansion member 140 is smaller than the inner diameter of the main body portion 210 of the outer catheter 200, the operator can smoothly move the inner catheter 100 to the proximal end side. . Further, since the maximum outer diameter portion 143a of the distal end tapered portion 143 of the expansion member 140 is larger than the inner diameter of the main body portion 210 of the outer catheter 200, the operator can easily move the inner catheter 100 to the proximal end side, The stepped portion 144 of the expansion member 140 (the base end portion of the distal end tapered portion 143 of the expansion member 140) can be easily brought into contact with the distal end portion of the outer catheter 200.

  Next, as shown in FIG. 7, the surgeon expands the expansion member 140 with a second internal pressure larger than the first internal pressure. The expansion member 140 is deformed into the second expanded state in which the maximum outer diameter portion 143a of the tip tapered portion 143 and the maximum outer diameter portion 146a of the intermediate portion 146 are larger than those in the first expanded state. When the expansion member 140 is deformed to the second expanded state, the maximum outer diameter portion 143a of the distal end tapered portion 143 of the expansion member 140 is deformed to a size substantially equal to the outer diameter of the distal end portion of the outer catheter 200. Further, the expansion member 140 is deformed so that the maximum outer diameter portion 146a of the intermediate portion 146 of the expansion member 140 is larger than the inner diameter of the main body portion 210 of the outer catheter 200 by being deformed to the second expanded state. Therefore, the intermediate part 146 of the expansion member 140 contacts the inner surface of the main body part 210 of the outer catheter 200 and presses the inner surface of the main body part 210 of the outer catheter 200. Therefore, the inner catheter 100 forms an assembly 10 </ b> A in which the outer catheter 200 and the inner catheter 100 are combined by applying an expansion force to the outer catheter 200 via the intermediate portion 146.

  When the surgeon forms the assembly 10 </ b> A, the distal end portion of the expansion member 140 (a certain range on the distal end side including the stepped portion 144 of the expansion member 140) is set to the distal end side of the outer catheter 200. Can be covered from. Thereby, the expansion member 140 fills a step generated on the outer surface of the outer catheter 200 and the outer surface of the expansion member 140.

  As shown in FIG. 9, the distal-side bending portion 219 of the main body 210 of the outer catheter 200 is deformed into a substantially linear shape in a state where the assembly 10A is formed. Therefore, the operator can smoothly move the assembly 10A by moving the assembly 10A in the living body lumen with the distal-side bending portion 219 deformed in a substantially linear shape.

  Next, the surgeon inserts the guide wire 300 into the lumen 125 of the inner tube shaft 120 of the inner catheter 100. Then, the surgeon inserts the assembly 10A percutaneously into the living body lumen along the guide wire 300 through the puncture portion formed in the living body. The surgeon pushes the outer catheter 200 relative to the inner catheter 100 to push the outer catheter 200 so that the distal end of the outer catheter 200 abuts against the distal tapered portion 143 of the expansion member 140. The surgeon advances the assembly 10A in the living body lumen by performing the above-described operation.

  In the expansion member 140 according to this embodiment, the outer surface of the intermediate portion 146 has a higher friction coefficient than the outer surface of the tip tapered portion 143. Therefore, a large frictional force is generated between the outer surface of the intermediate portion 146 and the inner surface of the main body portion 210 of the outer catheter 200 in a state where the assembly 10A is formed.

  The intermediate portion 146 of the expansion member 140 applies an expansion force to the distal end member 240 from the inside of the outer catheter 200 in a state where the assembly 10A is formed. The tip member 240 is deformed so as to be in close contact with the intermediate portion 146 of the expansion member 140, and prevents a gap from being formed between the tip member 240 and the expansion member 140.

  Further, the intermediate portion 146 of the expansion member 140 applies an expansion force to the first region 216 of the main body portion 210 of the outer catheter 200. The expansion member 140 presses the inner surface of the first region 216 of the main body 210 that is higher in rigidity than the tip member 240 and firmly adheres to the first region 216 of the main body 210. Therefore, the operator can prevent the expansion member 140 from being displaced in the lumen 215 of the outer catheter 200 when moving the assembly 10A.

  In addition, the axial length d3 of the intermediate portion 146 of the expansion member 140 is equal to the axial length d1 of the portion of the distal end member 240 that protrudes more distally than the main body portion 210 of the outer catheter 200 and the first region 216. It is longer than the numerical value obtained by adding the axial length d2. Therefore, when forming the assembly 10A in which the outer catheter 200 and the inner catheter 100 are combined, a part of the intermediate portion 146 of the expansion member 140 is located in the second region 217 of the main body portion 210 of the outer catheter 200, and The expansion force is applied to the two regions 217. The expansion member 140 applies an expansion force to the distal end member 240 and the second region 217 having higher rigidity than the first region 216 of the main body 210. Therefore, the expansion force by the expansion member 140 is supported by the second region 217 and It is possible to more firmly adhere to the inner surface of the catheter 200. Therefore, the surgeon can further prevent the expansion member 140 from being displaced in the lumen 215 of the outer catheter 200 when moving the assembly 10A.

  After delivering the distal end portion of the outer catheter 200 to the target site in the living body, the surgeon has the maximum outer diameter portion 143a of the distal end tapered portion 143 of the expansion member 140 larger than the inner diameter of the outer catheter 200 as shown in FIG. The expansion member 140 is contracted to be a third internal pressure lower than the first internal pressure so as to be reduced. Further, the surgeon contracts the expansion member 140 to the third internal pressure so that the outer diameter of the intermediate portion 146 of the expansion member 140 is smaller than the inner diameter of the main body portion 210 of the outer catheter 200.

  Next, the operator removes the inner catheter 100 from the inner lumen 215 of the main body 210 of the outer catheter 200 in a state where the outer catheter 200 is placed in the living body lumen.

  When the inner catheter 100 is extracted as described above, the maximum outer diameter portion 143a of the distal end tapered portion 143 of the expansion member 140 is smaller than the inner diameter of the main body portion 210 of the outer catheter 200. Therefore, the operator can easily remove the inner catheter 100 from the outer catheter 200. In the expansion member 140 according to the present embodiment, the outer surface of the tip tapered portion 143 has a lower coefficient of friction than the outer surface of the intermediate portion 146. Therefore, when the inner catheter 100 is removed, it is possible to prevent the distal end tapered portion 143 of the expansion member 140 from being caught by the outer catheter 200 and the movement of the expansion member 140 is inhibited.

  When the inner catheter 100 is removed from the main body 210 of the outer catheter 200, the outer catheter 200 is deformed into a shape having a distal-end bending portion 219 (see FIG. 1). Therefore, the surgeon can engage the distal-side curved portion 219 of the outer catheter 200 to a desired position in the living body lumen.

  Next, the surgeon delivers a predetermined medical device (for example, a balloon catheter or the like) to the target site in the living body lumen via the lumen 215 of the main body 210 of the outer catheter 200. The inner surface of the main body 210 of the outer catheter 200 according to the present embodiment is formed with a smaller friction coefficient than the outer surface of the intermediate portion 146 of the expansion member 140. Therefore, the surgeon can smoothly move the medical device when delivering the medical device via the lumen 215 of the main body 210 of the outer catheter 200.

  As described above, the inner catheter 100 according to this embodiment includes the inner tube shaft 120 having the inner lumen 125 through which the guide wire 300 can be inserted, and the outer tube shaft 130 disposed so as to cover a part of the inner tube shaft 120. And an expansion member 140 disposed at the distal end portion 121 of the inner tube shaft 120 and the distal end portion 131 of the outer tube shaft 130. The expansion member 140 has a distal end tapered portion 143, a proximal end tapered portion 145, and an intermediate portion 146 disposed between the distal end tapered portion 143 and the proximal end tapered portion 145. Further, in the expansion member 140, when the expansion member 140 is expanded, the maximum outer diameter portion 143a of the distal end tapered portion 143 is larger than the maximum outer diameter portion 146a of the intermediate portion 146 and the maximum outer diameter portion 145a of the proximal end tapered portion 145. It is comprised so that it may become. The outer surface of the intermediate portion 146 of the expansion member 140 has a higher friction coefficient than the outer surface of the tip tapered portion 143.

  In the inner catheter 100 configured as described above, when the expansion member 140 is expanded in a state in which a part of the expansion member 140 protrudes from the distal end of the outer catheter 200, the distal end portion of the expansion member 140 extends the distal end of the outer catheter 200. Cover from the distal end side of the outer catheter 200. Therefore, the inner catheter 100 inserts the assembly 10 </ b> A into the living body lumen in a state where the tip tapered portion 143 of the expansion member 140 fills the step generated on the outer surface of the outer catheter 200 and the outer surface of the expansion member 140. Enable. As a result, the assembly 10A in which the inner catheter 100 and the outer catheter 200 are combined prevents the distal end of the outer catheter 200 from being caught on the puncture portion and the inner wall of the living body lumen when the assembly 10A is inserted into the living body lumen. Can be prevented. Thereby, the inner catheter 100 can reduce the insertion resistance into the living body lumen in a state where the assembly 10A is formed. Further, since the expansion member 140 has a frictional resistance higher than that of the tip tapered portion 143, the expansion member 140 prevents the expansion member 140 from being displaced with respect to the outer catheter 200 in a state where the assembly 10A is formed. Can do. Thereby, the inner catheter 100 can improve the passage through the living body lumen in a state where the assembly 10A is formed.

  In the inner catheter 100, the inner tube shaft 120 includes a first region 126 and a second region 127 having a color different from that of the first region 126. The first region 126 is formed at a position corresponding to the tip tapered portion 143 of the inner tube shaft 120. Therefore, the surgeon can visually confirm the position of the first region 126 even when the expansion member 140 is folded (unexpanded state), and the position of the tip tapered portion 143 of the expansion member 140 can be easily determined. Can grasp. Accordingly, when the expansion member 140 is protruded from the distal end of the outer catheter 200, the operator can easily and reliably protrude the distal end tapered portion 143 of the expansion member 140 from the outer catheter 200. In addition, since the operator can easily grasp the position of the distal end tapered portion 143 when aligning the maximum outer diameter portion 143a of the expansion member 140 with the distal end of the outer catheter 200, the assembly 10A is formed. It becomes possible to carry out the work to be performed easily.

  In the inner catheter 100, the outer surface of the distal end tapered portion 143 of the expansion member 140 includes a first covering portion 151 having a lower coefficient of friction than the outer surface of the intermediate portion 146 of the expansion member 140. The expansion member 140 has a stepped portion 144 between the proximal end (maximum outer diameter portion 143a) of the distal end tapered portion 143 and the distal end of the intermediate portion 146. And the 1st coating | coated part 151 is arrange | positioned so that the level | step-difference part 144 may be covered at least. In the inner catheter 100 configured as described above, the stepped portion 144 formed in the vicinity of the maximum outer diameter portion 143a of the distal end tapered portion 143 of the expansion member 140 is easily in contact with the living body lumen. Therefore, the slidability of the stepped portion 144 in the living body lumen can be enhanced by covering the stepped portion 144 with the first covering portion 151. Therefore, the inner catheter 100 is improved in passage through a living body lumen in a state where the assembly 10A is formed.

  In the inner catheter 100, a hydrophobic second covering portion 152 having a higher friction coefficient than that of the constituent material of the expansion member 140 is disposed on at least a part of the outer surface of the intermediate portion 146 of the expansion member 140. The first covering portion 151 is a hydrophilic covering portion having a lower coefficient of friction than the second covering portion 152, and is also disposed in a part of the intermediate portion 146 located on the base end side with respect to the stepped portion 144. In the inner catheter 100, the first covering portion 151 having hydrophilicity is disposed up to a part of the intermediate portion 146 located on the proximal end side with respect to the stepped portion 144, so that the stepped portion 144 is more reliably secured to the first covering portion. 151 is covered. Moreover, since the 1st coating | coated part 151 is arrange | positioned to the intermediate part 146 without the interruption | blocking in the level | step-difference part 144, the inner side catheter 100 can prevent suitably the 1st coating | coated part 151 peeling with the level | step-difference part 144. it can.

  The medical device 10 includes an inner tube shaft 120 having a lumen 125 through which the guide wire 300 can be inserted, an outer tube shaft 130 disposed so as to cover a part of the inner tube shaft 120, and the inner tube shaft 120. An inner catheter 100 including a distal end portion 121 and an expansion member 140 disposed at the distal end portion 131 of the outer tube shaft 130; and an outer catheter 200 including a lumen 215 into which the inner catheter 100 can be inserted. The expansion member 140 includes a distal end taper portion 143, a proximal end taper portion 145, and an intermediate portion 146 disposed between the distal end taper portion 143 and the proximal end taper portion 145. The expansion member 140 is an expansion member. When the member 140 is expanded, the maximum outer diameter portion 143a of the distal end tapered portion 143 is changed to the maximum outer diameter portion 146a of the intermediate portion 146 and the proximal end tapered portion 145. Maximum outer diameter 145a, and is configured to be larger than the inner diameter of the outer catheter 200, the outer surface of the intermediate portion 146 has a higher coefficient of friction than the outer surface of the tip tapered portion 143.

  In the medical device 10 configured as described above, when the expansion member 140 is expanded in a state where a part of the expansion member 140 protrudes from the distal end of the outer catheter 200, the distal end portion of the expansion member 140 extends outward from the distal end of the outer catheter 200. Cover from the distal end side of the catheter 200. Therefore, the medical device 10 inserts the assembly 10 </ b> A into the living body lumen in a state where the tip tapered portion 143 of the expansion member 140 fills the step generated on the outer surface of the outer catheter 200 and the outer surface of the expansion member 140. Enable. As a result, the assembly 10A in which the inner catheter 100 and the outer catheter 200 are combined prevents the distal end of the outer catheter 200 from being caught on the puncture portion and the inner wall of the living body lumen when the assembly 10A is inserted into the living body lumen. Can be prevented. Thereby, the medical instrument 10 can reduce the insertion resistance of the assembly 10A into the living body lumen. Further, since the expansion member 140 has a frictional resistance higher than that of the tip tapered portion 143, the expansion member 140 prevents the expansion member 140 from being displaced with respect to the outer catheter 200 in a state where the assembly 10A is formed. Can do. Thereby, the medical instrument 10 is improved in the passage through the living body lumen in a state where the assembly 10A is formed.

  In the medical device 10, the outer surface of the intermediate portion 146 of the expansion member 140 has a region (second covering portion 152) formed with a higher coefficient of friction than the inner surface forming the lumen 215 of the outer catheter 200. . Therefore, the operator can smoothly move the medical device relative to the outer catheter 200 when the medical device is inserted into the lumen 215 of the outer catheter 200 after removing the inner catheter 100 from the outer catheter 200. Become.

  Further, in the medical instrument 10, the expansion member 140 configures a first expanded state and a second expanded state in which the maximum outer diameter portion 146a of the intermediate portion 146 is larger than that in the first expanded state. When the expansion member 140 is in the first expanded state, the maximum outer diameter portion 146a of the intermediate portion 146 is smaller than the inner diameter of the outer catheter 200, and the maximum outer diameter portion 143a of the tip tapered portion 143 is smaller than the inner diameter of the outer catheter 200. Also grows. Therefore, the surgeon moves the inner catheter 100 to the proximal end side with respect to the outer catheter 200 in a state where the expansion member 140 is deformed to the first expanded state, whereby the proximal end of the distal end tapered portion 143 of the expansion member 140 is moved. The portion can be easily aligned with the distal end portion of the outer catheter 200.

  In the medical instrument 10, the outer catheter 200 includes a main body 210 and a distal end member 240 that is disposed on the distal end side of the main body 210 and is more flexible than the main body 210. The axial length d3 of the intermediate portion 146 of the expansion member 140 is longer than the axial length d1 of the portion of the distal end member 240 that protrudes more distally than the main body portion 210. Therefore, when the expansion member 140 is expanded, the medical device 10 can reliably apply an expansion force from the intermediate portion 146 of the expansion member 140 to the distal end member 240 of the outer catheter 200. Thereby, when the expansion member 140 expands, the tip member 240 is deformed so as to be in close contact with the intermediate portion 146 of the expansion member 140. Thereby, the medical device 10 can prevent a gap from being formed between the distal end member 240 and the intermediate portion 146 of the expansion member 140.

  Further, in the medical device 10, the main body 210 of the outer catheter 200 includes a first region 216 and a second region 217 in which the reinforcing body 218 is disposed while being disposed on the proximal end side of the first region 216. I have. The axial length d3 of the intermediate portion 146 of the expansion member 140 is the axial length d1 of the portion of the distal end member 240 that protrudes more distally than the main body 210 and the axial length d2 of the first region 216. It is longer than the number added. Therefore, when the expansion member 140 is expanded, the expansion member 140 can apply an expansion force from the intermediate portion 146 of the expansion member 140 to the second region 217 of the main body portion 210 of the outer catheter 200. Thereby, the expansion member 140 presses the inner surface of the second region 217 of the main body 210 having higher rigidity than the first member 216 and the first region 216 of the main body 210, and against the first region 217 of the main body 210. It is fixed while firmly adhering. Therefore, the surgeon can prevent the expansion member 140 from being displaced from the outer catheter 200 when moving the assembly 10A in a state where the assembly 10A is formed.

  Further, in the medical instrument 10, the distal end portion of the main body portion 210 of the outer catheter 200 has a distal end side curved portion 219 that is curved with respect to the axial direction of the main body portion 210. The distal-side bending portion 219 expands in a state where the intermediate portion 146 of the expansion member 140 is disposed at a position including the proximal end side with respect to the proximal end 219a of the distal-end-side bending portion 219. It deforms into a shape. Therefore, the surgeon expands the expansion member 140 and deforms the distal-side curved portion 219 of the main body 210 of the outer catheter 200 into a substantially linear shape, whereby the assembly 10A in which the outer catheter 200 and the inner catheter 100 are combined. Can be smoothly moved in the living body lumen. Further, the operator can deform the outer catheter 200 into a shape in which the distal-side bending portion 219 is formed by contracting and removing the inner catheter 100 inserted into the outer catheter 200. Therefore, the surgeon can appropriately engage the distal side bending portion 219 of the outer catheter 200 to a desired position in the living body lumen by deforming the outer catheter 200 into a shape having the distal side bending portion 219.

  In the medical instrument 10, the expansion member 140 forms a stepped portion 144 between the proximal end (maximum outer diameter portion) 143 a of the distal tapered portion 143 and the distal end of the intermediate portion 146 when expanded. The stepped portion 144 has a curved portion 144a that is curved from the tip tapered portion 143 side toward the intermediate portion 146 side. Therefore, the medical instrument 10 can suitably prevent the living body lumen from being damaged when the stepped portion 144 comes into contact with the living body lumen.

  Further, the medical method according to the present embodiment includes an inner tube shaft 120 having an inner lumen 125 through which the guide wire 300 can be inserted, an outer tube shaft 130 disposed so as to cover a part of the inner tube shaft 120, an inner tube An inner catheter 100 including an expansion member 140 disposed at a distal end portion 121 of the tube shaft 120 and a distal end portion 131 of the outer tube shaft 130; an outer catheter 200 including a lumen 215 into which the inner catheter 100 can be inserted; The expansion member 140 includes a distal tapered portion 143, a proximal tapered portion 145, and an intermediate portion 146 disposed between the distal tapered portion 143 and the proximal tapered portion 145, and the outer catheter 200. The inner catheter 100 is inserted into the inner lumen 215 and a part of the expansion member 140 protrudes from the distal end of the outer catheter 200. The expansion member 140 is expanded by the first internal pressure, the inner catheter 100 is moved so that the maximum outer diameter portion 143a of the distal end tapered portion 143 of the expansion member 140 contacts the distal end portion of the outer catheter 200, and the expansion member 140 is moved to the first position. The assembly is expanded with a second internal pressure larger than the internal pressure to form an assembly 10A of the outer catheter 200 and the inner catheter 100, and the assembly 10A is inserted into the living body lumen percutaneously.

  In the medical method described above, the expansion member 140 is expanded with the first internal pressure in a state where a part of the expansion member 140 included in the inner catheter 100 protrudes from the distal end of the outer catheter 200. Then, in the medical method, the inner catheter 100 is moved so that the maximum outer diameter portion 143 a of the distal end tapered portion 143 of the expansion member 140 is in contact with the distal end portion of the outer catheter 200. Thereby, in the medical method, the distal end tapered portion 143 of the expansion member 140 can be easily disposed on the distal end side of the outer catheter 200. In the medical method, when the expansion member 140 is expanded, the distal end portion of the expansion member 140 can cover the distal end of the outer catheter 200 from the distal end side of the outer catheter 200. Therefore, in the medical method, the assembly 10 </ b> A can be inserted into the living body lumen in a state in which the tip tapered portion 143 of the expansion member 140 fills the step generated on the outer surface of the outer catheter 200 and the outer surface of the expansion member 140. it can. Thereby, the medical method can reduce the insertion resistance into the living body lumen.

  In the medical method described above, the expansion member 140 has a third internal pressure that is lower than the first internal pressure so that the maximum outer diameter portion 143a of the tip tapered portion 143 of the expansion member 140 is smaller than the inner diameter of the outer catheter 200. The inner catheter 100 is removed from the lumen 215 of the outer catheter 200 in a state where the outer catheter 200 is indwelled in the living body lumen. In the above medical method, when the inner catheter 100 is removed, the proximal end portion of the distal end tapered portion 143 of the expansion member 140 is smaller than the inner diameter of the main body portion 210 of the outer catheter 200. Therefore, the operator can easily remove the inner catheter 100 from the outer catheter 200.

  As mentioned above, although the medical elongate body, the medical device, and the medical method which concern on this invention were demonstrated through embodiment, this invention is not limited only to the content demonstrated in embodiment, and description of a claim It is possible to change appropriately based on this.

  For example, the cross-sectional shape of the expansion member, the size relationship of the dimensions of each part, and the like are not limited to those described with reference to the drawings, and can be changed as appropriate.

  For example, each constituent member constituting the medical elongate body and the medical instrument can be replaced with any component that can exhibit the same function. Further, the medical elongated body and the medical instrument may be appropriately added with any component (member) or the like not specifically described in the specification, or may omit the member to be used as appropriate. it can.

10 medical devices,
10A assembly,
100 inner catheter (medical long body),
110 shaft,
120 inner tube shaft,
121 The tip of the inner tube shaft,
125 lumen of the inner tube shaft,
126 the first region of the inner tube shaft,
127 the second region of the inner tube shaft,
130 outer tube shaft,
131 The tip of the outer tube shaft,
135 lumen of outer tube shaft,
140 expansion member,
143 Tapered tip,
143a The maximum outer diameter portion of the tip tapered portion,
144 Stepped part,
144a curved portion,
144b vertical wall,
145 proximal end taper,
145a The maximum outer diameter portion of the proximal tapered portion,
146 middle part,
146a maximum outer diameter portion of the intermediate portion,
146b the tip of the middle part,
151 first covering portion,
152 second covering portion,
200 outer catheter,
210 body,
215 lumen of the body,
216 the first region of the outer catheter;
217 outer catheter second region,
218 reinforcement,
219 distal side bending portion,
219a, a proximal end of the distal side bending portion,
240 tip member,
300 guidewire,
d1 The axial length of the portion of the tip member that protrudes further toward the tip than the main body,
d2 the axial length of the first region of the main body,
d3 The axial length of the intermediate portion of the expansion member.

Claims (13)

An inner tube shaft having a lumen through which a guide wire can be inserted;
An outer tube shaft arranged to cover a part of the inner tube shaft;
An expansion member disposed at the tip of the inner tube shaft and the tip of the outer tube shaft,
The expansion member has a distal end tapered portion, a proximal end tapered portion, and an intermediate portion disposed between the distal end tapered portion and the proximal end tapered portion,
The expansion member is configured such that when the expansion member is expanded, the maximum outer diameter portion of the tip tapered portion is larger than the maximum outer diameter portion of the intermediate portion and the maximum outer diameter portion of the proximal end taper portion. And
The medical long body, wherein the outer surface of the intermediate portion has a higher coefficient of friction than the outer surface of the tapered end portion. The inner tube shaft includes a first region and a second region having a color different from that of the first region,
The medical long body according to claim 1, wherein the first region is formed at a position corresponding to the tip tapered portion of the inner tube shaft. The outer surface of the tip tapered portion includes a first covering portion having a lower coefficient of friction than the outer surface of the intermediate portion,
The expansion member has a step portion between a base end of the tip tapered portion and a tip of the intermediate portion,
The medical elongated body according to claim 1, wherein the first covering portion is disposed so as to cover at least the stepped portion. A hydrophobic second covering portion having a higher coefficient of friction than the constituent material of the expansion member is disposed on at least a part of the outer surface of the intermediate portion,
The first covering portion is a hydrophilic covering portion having a lower coefficient of friction than the second covering portion, and is also disposed in a part of the intermediate portion located on the base end side with respect to the stepped portion. The medical elongated body according to claim 3. An inner tube shaft having a lumen through which a guide wire can be inserted;
An outer tube shaft arranged to cover a part of the inner tube shaft;
An inner catheter comprising: an expansion member disposed at a distal end portion of the inner tube shaft and a distal end portion of the outer tube shaft;
An outer catheter having a lumen into which the inner catheter can be inserted,
The expansion member has a distal end tapered portion, a proximal end tapered portion, and an intermediate portion disposed between the distal end tapered portion and the proximal end tapered portion,
When the expansion member is expanded, the expansion member has a maximum outer diameter portion of the distal end taper portion, a maximum outer diameter portion of the intermediate portion, a maximum outer diameter portion of the proximal end taper portion, and an inner diameter of the outer catheter. Is configured to be larger than
The medical device according to claim 1, wherein the outer surface of the intermediate portion has a higher coefficient of friction than the outer surface of the tip tapered portion.   The medical device according to claim 5, wherein an outer surface of the intermediate portion of the expansion member has a region formed with a higher coefficient of friction than an inner surface forming a lumen of the outer catheter. The expansion member constitutes a first expanded state and a second expanded state in which the maximum outer diameter portion of the intermediate portion is larger than the first expanded state,
When the expansion member is in the first expanded state, the maximum outer diameter portion of the intermediate portion is smaller than the inner diameter of the outer catheter, and the maximum outer diameter portion of the tip tapered portion is smaller than the inner diameter of the outer catheter. The medical device according to claim 5 or 6, which is large. The outer catheter includes a main body portion, and a distal end member that is disposed on a distal end side of the main body portion and is more flexible than the main body portion,
The length in the axial direction of the intermediate portion of the expansion member is longer than the length in the axial direction of a portion of the distal end member that protrudes toward the distal end side relative to the main body portion. The medical device described.   The main body portion of the outer catheter includes a first region and a second region disposed on the proximal end side of the first region and a reinforcing body, and the axial direction of the intermediate portion of the expansion member The length of is longer than a numerical value obtained by adding an axial length of a portion of the distal end member protruding to the distal end side of the main body portion and an axial length of the first region. Medical instrument. The distal end portion of the body portion of the outer catheter has a distal-side curved portion that is curved with respect to the axial direction of the body portion,
The distal-side bending portion expands in a state in which the intermediate portion of the expansion member is disposed at a position including the proximal end side with respect to the proximal end of the distal-end bending portion, so that the distal-side bending portion is substantially straight with respect to the axial direction. The medical device according to claim 8 or 9, which is deformed into a shape. The expansion member, when expanded, forms a stepped portion between the proximal end of the distal tapered portion and the distal end of the intermediate portion,
The medical device according to any one of claims 5 to 10, wherein the stepped portion has a curved portion that is curved from the tip tapered portion side toward the intermediate portion side. An inner tube shaft having a lumen through which a guide wire can be inserted, an outer tube shaft disposed so as to cover a part of the inner tube shaft, a distal end portion of the inner tube shaft, and a distal end portion of the outer tube shaft; An expansion catheter disposed on the inner catheter, and an outer catheter including a lumen into which the inner catheter can be inserted. The expansion member includes a distal end taper portion, a proximal end taper portion, An intermediate portion disposed between a distal tapered portion and the proximal tapered portion,
Inserting the inner catheter into the lumen of the outer catheter;
With the part of the expansion member protruding from the distal end of the outer catheter, the expansion member is expanded with a first internal pressure,
Moving the inner catheter such that the maximum outer diameter portion of the tip tapered portion of the expansion member contacts the tip of the outer catheter;
Expanding the expansion member with a second internal pressure greater than the first internal pressure;
Forming an assembly of the outer catheter and the inner catheter;
A medical method, wherein the assembly is inserted percutaneously into a biological lumen. Contracting the expansion member to a third internal pressure lower than the first internal pressure so that the maximum outer diameter portion of the distal tapered portion of the expansion member is smaller than the inner diameter of the outer catheter;
A medical method of removing the inner catheter from the lumen of the outer catheter while the outer catheter is placed in the living body lumen.