catheter

Abstract

To provide a catheter capable of achieving excellent operability.SOLUTION: A catheter 100 as a catheter 100 which is detained in the coronary sinus of the heart and supplies a heart muscle protective liquid to the coronary artery comprises: a tubular body 10 having a plurality of lumens 20; a pore part 13 for supplying a heart muscle protective liquid, formed in a distal end part 10a of the tubular body 10, and communicated with a first lumen 21; a reinforcement tube 40 inserted into a second lumen 22; and an operation wire 50 inserted into the reinforcement tube 40. The reinforcement tube 40 extends from a proximal side to the distal end part 10a of the tubular body 10. A tip 50a of the operation wire 50 is derived from a distal end of the reinforcement tube 40, and is fixed to the distal end part 10a of the tubular body 10 at a distal side from a distal end 40a of the reinforcement tube 40.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a catheter. [Background technology]

[0002] An example of the catheter is described in Patent Document 1. The catheter of Patent Document 1 is configured with a tubular body (referred to in the document as a catheter tube) having a first lumen (referred to in the document as a main lumen) and a second lumen (referred to in the document as a wire lumen), and two operating wires (referred to in the document as a first wire and a second wire) inserted into the second lumen. The tips of the two operating wires are each fixed to the distal end of the tubular body. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2015-173821 A Summary of the Invention [Problem to be solved by the invention]

[0004] According to the investigations of the present inventors, there is room for improvement in the operability of the catheter structure of Patent Document 1.

[0005] The present invention has been made in consideration of the above problems, and an object of the present invention is to provide a catheter that can achieve good operability. [Means for solving the problem]

[0006] According to the present invention, there is provided a catheter for supplying cardioplegia to a coronary artery by being placed in the coronary sinus of a heart, comprising: A tubular body having a plurality of lumens; a hole for supplying the cardioplegia solution formed at a distal end of the tubular body and communicating with the first lumen; A reinforcing tube inserted into the second lumen; An operating wire inserted through the reinforcing tube; having the material constituting the reinforcing tube is a material having a bending rigidity greater than that of the material constituting the tubular body, the stiffening tube extends from the proximal end of the tubular body to the distal end, A tip end of the operating wire is led out from the distal end of the reinforcing tube and fixed to the distal end of the tubular body on the distal side of the distal end of the reinforcing tube. And, When the operating wire is pulled, a portion of the tubular body distal to the distal end of the reinforcing tube is selectively bent. A catheter is provided. Effect of the Invention

[0007] According to the present invention, good operability of the catheter can be achieved. [Brief description of the drawings]

[0008] [Figure 1] 1 is a diagram showing the overall configuration of a catheter according to an embodiment. FIG. [Diagram 2] 2(a) and 2(b) are views showing the distal end portion of a catheter according to an embodiment, where FIG. 2(a) is a side view and FIG. 2(b) is a cross-sectional view taken along the axial direction of the catheter. [Diagram 3] Figures 3(a) and 3(b) are diagrams showing a catheter according to an embodiment, with Figure 3(a) being a cross-sectional view taken along line AA in Figure 2(a) and Figure 3(b) being a cross-sectional view taken along line BB in Figure 2(a). [Figure 4] 1 is a diagram showing the overall configuration of an introducer to which a catheter according to an embodiment is connected. FIG. [Diagram 5]Figures 5(a) and 5(b) are diagrams showing the state in which a catheter of this embodiment is connected to an introducer, with Figure 5(a) showing a state in which the distal end of the catheter does not protrude from the distal end of the introducer, and Figure 5(b) showing a state in which the distal end of the catheter protrudes from the distal end of the introducer. [Figure 6] Figures 6(a) and 6(b) are diagrams showing the connection structure between a catheter and an introducer in this embodiment, with Figure 6(a) showing a state in which the catheter and introducer are separated, and Figure 6(b) showing a state in which the catheter and introducer are connected. [Figure 7] FIG. 13 is a diagram showing the overall configuration of a catheter according to a first modified example. [Figure 8] Figures 8(a) and 8(b) are side views showing the internal structure of the operating part in the first modified example, of which Figure 8(a) shows a state in which the operating part is swung in one circumferential direction, and Figure 8(b) shows a state in which the operating part is swung in the opposite circumferential direction. [Figure 9] FIG. 11 is a plan view of an operation unit in a first modified example. [Figure 10] Figures 10(a) to 10(f) are figures for explaining the operation of the catheter of the first modified example, of which Figure 10(a) shows a state in which the distal end is extended, Figure 10(b) shows a state in which the distal end is bent, Figure 10(c) shows a state in which the distal end is further bent than the state shown in Figure 10(b), Figure 10(d) is a side view showing the internal structure of the operating unit in a state corresponding to Figure 10(a), Figure 10(e) is a side view showing the internal structure of the operating unit in a state corresponding to Figure 10(b), and Figure 10(f) is a side view showing the internal structure of the operating unit in a state corresponding to Figure 10(c). [Figure 11]Figures 11(a) to 11(f) show the operation receiving portion in the first modified example, with Figure 11(a) being an oblique view, Figure 11(b) being a plan view, Figure 11(c) being a bottom view, Figure 11(d) being a side view showing the operation receiving portion 75 and its surrounding structure, Figure 11(e) being a cross-sectional view along line AA shown in Figure 11(d), and Figure 11(f) being a cross-sectional view along line BB shown in Figure 11(d). [Figure 12] Figures 12(a) and 12(b) are side views of the operating part in the second modified example, of which Figure 12(a) shows a state in which the operating part is swung in one circumferential direction, and Figure 12(b) shows a state in which the operating part is swung in the opposite circumferential direction. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment of the present invention will be described with reference to Fig. 1 to Fig. 6(b). In all the drawings, the same components are denoted by the same reference numerals, and the description thereof will be omitted where appropriate. In Fig. 1, the balloon 60 is shown in an inflated state for the sake of convenience, but in reality, the balloon 60 is not inflated in normal times before use. In addition, the left-right positional relationship between the connecting part 15 and the second connecting part 113 is reversed between Figs. 5(a) and 5(b) and Figs. 6(a) and 6(b). The second hole portion 13b faces the front side of the paper in Fig. 2(a) and faces downward in Fig. 2(b). Fig. 2(a) shows the distal end portion of the catheter 100 as viewed in the direction of the arrow A shown in Fig. 3(a) and Fig. 3(b), and Fig. 2(b) is a cross-sectional view taken along the line B-B shown in Fig. 3(a) and Fig. 3(b). In Fig. 2(a), the first lumen 21 and the balloon 60 are shown by dashed lines, but the second lumen 22, the third lumen 23, and the fourth lumen 24 are not shown. In Fig. 2(b), the third lumen 23 is shown by a dashed line.

[0010] The embodiment described below is merely an example for facilitating understanding of the present invention, and is not intended to limit the present invention. In other words, the shapes, dimensions, arrangements, and other aspects of the components described below may be changed or improved without departing from the spirit of the present invention, and the present invention includes equivalents thereof. It is not necessary that the various components of the catheter 100 of the present invention exist independently of one another. It is acceptable for multiple components to be formed as a single member, for one component to be formed from multiple members, for one component to be a part of another component, or for part of one component to overlap with part of another component. In the following description, the distal side of the catheter 100 is also referred to as the tip side, and the proximal side is also referred to as the base side. The distal end portion refers to a certain range including the distal end (the most distal end) and its periphery, and the proximal end portion refers to a certain range including the proximal end (the most proximal end) and its periphery.

[0011] As shown in any one of FIG. 1 to FIG. 3(b), a catheter 100 according to this embodiment is placed in the coronary sinus of the heart to supply cardioplegia to the coronary arteries. The catheter 100 has a tubular body 10 (FIG. 1, etc.) having a plurality of lumens 20 (FIG. 3(a), etc.), a hole portion 13 (FIGS. 2(a), 2(b) etc.) for supplying myocardial protection solution formed at the distal end portion 10a of the tubular body 10 and communicating with the first lumen 21 (FIGS. 2(a), 2(b) etc.), a reinforcing tube 40 (FIG. 3(a) etc.) inserted into the second lumen 22 (FIG. 3(a) etc.), and an operating wire 50 (FIG. 2(b) etc.) inserted into the reinforcing tube 40. The reinforcing tube 40 extends from the proximal side to the distal end 10a of the tubular body 10, and the tip 50a of the operating wire 50 is led out from the distal end 40a of the reinforcing tube 40 and fixed to the distal end 10a of the tubular body 10 distal to the reinforcing tube 40.

[0012] According to this embodiment, the portion of the tubular body 10 proximal to the distal end 40a of the reinforcing tube 40 is reinforced by the reinforcing tube 40, thereby providing the tubular body 10 with appropriate stiffness and facilitating insertion of the catheter 100 into the biological lumen. On the other hand, a portion of the tubular body 10 distal to the distal end 40a of the reinforcing tube 40 (hereinafter referred to as the flexible portion 14) is not reinforced by the reinforcing tube 40 and is therefore more flexible than the portion proximal thereto. Therefore, by pulling the operating wire 50, a localized area of ​​the tubular body 10, i.e., the flexible portion 14, can be selectively bent with a large curvature. Moreover, since the flexible portion 14 can be easily bent with a large curvature, the branching selectivity of the catheter 100 is good. In this way, since the tubular body 10 can have both appropriate stiffness and good flexibility, the catheter 100 can have good operability.

[0013] The catheter 100 according to this embodiment is an intravascular catheter used by inserting the tubular body 10 into a blood vessel. By operating the operation unit 70 described below, the flexible portion 14 (see FIG. 1) of the tubular body 10 can be bent to orient the catheter 100 in one direction. More specifically, the flexible portion 14 refers to the range from the distal end 40 a of the reinforcing tube 40 to the distalmost end of the operating wire 50 in the tubular body 10 .

[0014] In this embodiment, the tubular body 10 is a long tubular member, and has a plurality of lumens 20 formed inside the tubular body 10 along the longitudinal direction of the tubular body 10 .

[0015] 2(a), the multiple lumens 20 include a first lumen 21, a second lumen 22, a third lumen 23, and a fourth lumen 24. However, the number of lumens 20 that the tubular body 10 has is not particularly limited, and may be, for example, five or more, or may be, for example, three or less.

[0016] The diameter (equivalent circle diameter) of the first lumen 21 is set to be larger than any of the diameters (equivalent circle diameters) of the second lumen 22, the third lumen 23, and the fourth lumen 24. More specifically, the diameter of the first lumen 21 is, for example, ⅔ or more of the diameter of the tubular body 10. The diameter of the second lumen 22 is set to a size larger than the diameters of the third lumen 23 and the fourth lumen 24, for example. The diameter of the fourth lumen 24 is set to be, for example, larger than the diameter of the third lumen 23 . However, the relationship between the diameters of the lumens 20 is not limited to the above example, and can be set appropriately depending on the application of each lumen 20.

[0017] The lumens 20 are arranged, for example, dispersed within the cross section of the tubular body 10 . More specifically, for example, the center of each lumen 20 is disposed eccentrically with respect to the axis of the tubular body 10. The second lumen 22, the third lumen 23, and the fourth lumen 24 are each disposed around the first lumen 21, and are disposed in the circumferential direction of the tubular body 10 in the order of the third lumen 23, the second lumen 22, and the fourth lumen 24. Also, the second lumen 22, the third lumen 23, and the fourth lumen 24 are each disposed eccentrically in the opposite direction to the direction in which the first lumen 21 is eccentric with respect to the axis of the tubular body 10.

[0018] The first lumen 21 is used, for example, as a fluid supply lumen for supplying a cardioplegic solution to a coronary artery. As described above, the first lumen 21 into which the cardioplegic solution is injected is formed with a relatively large diameter, so that the cardioplegic solution can be smoothly circulated in the inner cavity of the tubular body 10. The first lumen 21 is formed over the entire length of the tubular body 10. The distal end of the first lumen 21 opens at the distal end of the tubular body 10, and the proximal end of the first lumen 21 communicates with a liquid supply branch tube 31 (see FIG. 1). The cross-sectional shape of the first lumen 21 is not particularly limited, but is substantially circular in this embodiment. The diameter of the first lumen 21 may be uniform regardless of the position in the axial direction of the tubular body 10, or may vary depending on the position in the axial direction.

[0019] As described above, the hole 13 is formed in the distal end 10a of the tubular body 10. The hole 13 communicates with the first lumen 21, and the cardioplegic solution injected into the first lumen 21 is discharged from the hole 13 into the coronary artery.

[0020] The tubular body 10 has, as hole portions 13, a first hole portion 13a formed at the distal end of the tubular body 10 and a second hole portion 13b formed on the circumferential surface of the distal end portion 10a of the tubular body 10. The first hole 13a is an opening at the distal end of the first lumen 21. The second hole portion 13b is disposed proximal to the distal end of the tubular body 10. The second hole portion 13b is a side hole whose depth direction is perpendicular to the axis of the tubular body 10. One end of the second hole portion 13b communicates with the first lumen 21, and the other end of the second hole portion 13b opens on the outer circumferential surface of the distal end portion 10a of the tubular body 10. As an example, the second hole portion 13b is formed at a position opposed to the second lumen 22 by 180 degrees in the circumferential direction of the tubular body 10. However, the position where the second hole portion 13b is formed is not particularly limited, and it may be at a position on the circumferential surface of the distal end portion 10a of the tubular body 10 that provides good communication with the first lumen 21.

[0021] Since two holes 13 (first hole 13a and second hole 13b) are formed in the tubular body 10, even if one of the first hole 13a and the second hole 13b is blocked by biological tissue, the myocardial protective solution can be discharged smoothly from the other of the first hole 13a and the second hole 13b.

[0022] A reinforcing tube 40 is inserted into the inner cavity of the second lumen 22, and an operating wire 50 is inserted into the inner cavity of the reinforcing tube 40. The second lumen 22 is formed, for example, from the proximal end to the distal end 10a of the tubular body 10. The distal end of the second lumen 22 terminates proximally relative to the distal end of the tubular body 10, and the proximal end of the second lumen 22 is connected to a branch portion 30 described below. The cross-sectional shape of the second lumen 22 is not particularly limited, but in this embodiment, it is a substantially elliptical shape that is elongated in the circumferential direction of the tubular body 10. The diameter of the second lumen 22 may be uniform regardless of the position in the axial direction of the tubular body 10, or may vary depending on the position in the axial direction.

[0023] The third lumen 23 can be used, for example, to inject a liquid into a balloon 60, which will be described later. The third lumen 23 is formed from the proximal end to the distal end 10a of the tubular body 10. The distal end of the third lumen 23 is disposed in a region where a balloon 60 (described later) is formed, and the proximal end of the third lumen 23 is communicated with a balloon branch tube 32 (see FIG. 1). The cross-sectional shape of the third lumen 23 is not particularly limited, but is generally elliptical in this embodiment. The diameter of the third lumen 23 may be uniform regardless of the position in the axial direction of the tubular body 10, or may vary depending on the position in the axial direction.

[0024] The fourth lumen 24 is used, for example, to measure fluid pressure inside a biological lumen. The fourth lumen 24 is formed from the proximal end to the distal end of the tubular body 10. The distal end of the fourth lumen 24 opens at the distal end of the tubular body 10, and the proximal end of the fourth lumen 24 communicates with a branch tube 33 for pressure monitoring (see FIG. 1). The cross-sectional shape of the fourth lumen 24 is not particularly limited, but in this embodiment, it is a substantially elliptical shape that is elongated in the circumferential direction of the tubular body 10. The diameter of the fourth lumen 24 may be uniform regardless of the position in the axial direction of the tubular body 10, or may vary depending on the position in the axial direction.

[0025] The tubular body 10 is made of, for example, a resin material such as polyurethane, polyamide, etc. By making the tubular body 10 of a resin material such as polyurethane, polyamide, etc., the processability of the tubular body 10 becomes good.

[0026] It is also preferable that, for example, a hydrophilic layer (not shown) is formed on the outer circumferential surface of the tubular body 10. This can reduce the sliding resistance when the catheter 100 is inserted into the lumen of the introducer 110 described below or into the coronary sinus. The hydrophilic layer may be formed over the entire length of the tubular body 10, or may be formed over a partial length region on the distal end side of the tubular body 10. The material of the hydrophilic layer is not particularly limited, but examples thereof include hydrophilic resin materials such as maleic anhydride polymers such as polyvinyl alcohol (PVA) and copolymers thereof, and polyvinylpyrrolidone.

[0027] The diameter of the tubular body 10 is not particularly limited, but is preferably 2 mm or more and 5 mm or less. The total length of the tubular body 10 is not particularly limited, but is preferably 500 mm or more and 1000 mm or less. As shown in Figures 2(a) and 2(b), the outer diameter of the most distal end of the tubular body 10 may be slightly enlarged toward the distal side.

[0028] As described above, the reinforcing tube 40 is inserted into the second lumen 22. In the present embodiment, the diameter of the second lumen 22 is larger than the diameter of the reinforcing tube 40. Therefore, when the tubular body 10 is bent by operating the operating wire 50, the reinforcing tube 40 is allowed to move relative to the tubular body 10 in the axial direction. The reinforcing tube 40 is formed, for example, in the shape of a long hollow tube. For example, the inner diameter and the outer diameter of the reinforcing tube 40 are constant, and therefore the wall thickness of the reinforcing tube 40 is constant. However, the reinforcing tube 40 may be formed, for example, in a tapered shape in which the inner and outer diameters become smaller toward the distal side.

[0029] The reinforcing tube 40 is made of a metal material such as stainless steel (SUS). However, the material constituting the reinforcing tube 40 is not particularly limited, and may be any material having a bending rigidity greater than that of the material constituting the tubular body 10 .

[0030] The reinforcing tube 40 extends from the proximal side of the tubular body 10 to a portion near the proximal side of the arrangement region of the balloon 60. More specifically, the distal end 40a of the reinforcing tube 40 is arranged proximal to the arrangement region of the balloon 60. In other words, the balloon 60 is provided on the flexible section 14. Therefore, by pulling the operating wire 50 and bending the flexible section 14, the orientation (posture) of the balloon 60 can be adjusted. The reinforcing tube 40 is introduced, for example, from the second lumen 22 into the inside of the branched portion 30, which will be described later.

[0031] The operating wire 50 is inserted through the reinforcing tube 40 so as to be slidable relative to the reinforcing tube 40. The tip portion 50a of the operating wire 50 is led out to the distal side from the distal end 40a of the reinforcing tube 40. The tip portion 50a of the operating wire 50 led out from the reinforcing tube 40 passes through the second lumen 22 and is fixed to the distal end of the tubular body 10.

[0032] The tip 50a of the operating wire 50 is fixed to the distal end 10a of the tubular body 10, distal to the region where the balloon 60 is formed. When the operating wire 50 is pulled, the tubular body 10 is bent. When the tubular body 10 is bent, it is mainly the portion distal to the distal end 40a of the reinforcing tube 40, i.e., the flexible portion 14, that is bent.

[0033] The operating wire 50 is, for example, a stranded wire formed by twisting together a plurality of wires. However, the operating wire 50 may be formed from a single wire. The diameter of the operating wire 50 is not particularly limited, but is preferably 0.2 mm or more and 1 mm or less. The operating wire 50 is not particularly limited, but examples thereof include a metal wire such as low carbon steel (piano wire), stainless steel (SUS), a corrosion-resistant coated steel wire, titanium or a titanium alloy, or tungsten.

[0034] For example, a ring-shaped marker 11 is embedded near the distal end of the tubular body 10. The outer circumferential surface of the marker 11 may be exposed to the outer circumferential surface of the tubular body 10, for example. The tip 50a of the operating wire 50 is fixed to the marker 11, for example. More specifically, as shown in FIG. 2(b), a tip portion 50a of the operating wire 50 is fixed to the marker 11 by, for example, an adhesive 12. However, the method for fixing the operating wire 50 to the marker 11 is not particularly limited, and solder bonding, crimping, or the like may be used.

[0035] The marker 11 is made of an X-ray impermeable material such as platinum, tungsten, etc. By using the position of the marker 11 as an index, the position of the distal end portion 10a of the tubular body 10 in the lumen of the living body can be accurately recognized under X-ray (radiation) observation.

[0036] As shown in Figures 2(a) and 2(b), the catheter 100 further includes a balloon 60, for example, provided on the outer periphery of the distal end portion 10a of the tubular body 10 and in communication with the third lumen 23.

[0037] The balloon 60 is, for example, a stretchable member formed in a sheet shape from a soft resin material. The soft resin material is not particularly limited, but examples thereof include soft resin materials such as polyamide, polyolefin, polyvinyl chloride, polyurethane, polyphenylene sulfide, fluororesin, and polyester, as well as rubber materials such as polyurethane elastomer, polyamide elastomer, silicone rubber, and latex rubber.

[0038] The balloon 60 is made of, for example, a single-layer or two or more-layer resin sheet. The balloon 60 is molded into a cylindrical shape or the like, and is attached to the tubular body 10 in a liquid-tight manner in a state where it circumferentially surrounds the outer circumferential surface of the distal end portion 10a of the tubular body 10. In the present embodiment, as an example, the distal end 61 and the proximal end 62 of the balloon 60 are each provided with an adhesive or other fastening portion (not shown), and the balloon 60 is fixed in a liquid-tight and circumferential manner to the tubular body 10. The portion of the balloon 60 that is not fixed to the outer circumferential surface of the tubular body 10 (the intermediate portion excluding the distal end 61 and the proximal end 62) is referred to as an intermediate portion 63. However, the method of attaching the balloon 60 to the tubular body 10 is not particularly limited, and the balloon 60 may be attached to the tubular body 10 by wrapping a string-like member around the proximal end 62 and the distal end 61 of the balloon 60, respectively.

[0039] Here, the tubular body 10 has a balloon hole 23a formed on the outer circumferential surface of the distal end portion 10a of the tubular body 10. The balloon hole 23a communicates with the third lumen 23, and liquid (not shown) such as physiological saline injected into the third lumen 23 is discharged into the balloon 60 from the balloon hole 23a. More specifically, the balloon hole 23a is formed in the formation region of the balloon 60. The balloon hole 23a is, for example, a side hole whose depth direction is perpendicular to the axial direction of the tubular body 10. One end of the balloon hole 23a communicates with the inside of the balloon 60, and the other end of the balloon hole 23a communicates with the distal end of the third lumen 23.

[0040] When a liquid such as physiological saline is injected into the balloon 60 through the third lumen 23 and the balloon hole 23a, the balloon 60 expands outward from the tubular body 10 (see FIG. 2(b)). More specifically, as shown in FIG. 2(a), when the balloon 60 is not expanded, the circumferential surface of the balloon 60 is disposed along the outer circumferential surface of the tubular body 10. When the balloon 60 is expanded, as shown in FIG. 2(b), the middle portion 63 of the balloon 60 expands (protrudes) outward from the tubular body 10. In this embodiment, the region where the balloon 60 is formed is a region of the tubular body 10 that is proximal to the second hole portion 13b.

[0041] As shown in Fig. 1, the proximal end of the tubular body 10 is connected to a cylindrical branch section 30. The branch section 30 is provided with a branch tube 31 for liquid delivery, a branch tube 32 for a balloon, and a branch tube 33 for a pressure monitor.

[0042] For example, four through holes are formed inside the branching portion 30 along the axial direction of the branching portion 30. Here, the four through holes are referred to as a first through hole, a second through hole, a third through hole, and a fourth through hole, respectively. A first lumen 21 is connected to the first through hole. A liquid supply branch tube 31 is connected to the first through hole. Thus, the first lumen 21 and the liquid supply branch tube 31 communicate with each other via a branch section 30. A liquid supply connector 31a (see FIG. 1) is provided at the proximal end of the liquid supply branch tube 31. A liquid supply syringe (not shown) is attached to the liquid supply connector 31a. The second through-hole is connected to the second lumen 22. The reinforcing tube 40 and the operating wire 50 are inserted through the second through-hole. From the second through-hole, the proximal end portions of the reinforcing tube 40 and the operating wire 50 are led out toward the operating section 70 (see FIG. 1). The third through-hole is connected to the third lumen 23. The third through-hole is connected to the balloon branch pipe 32. Thus, the third lumen 23 and the balloon branch pipe 32 communicate with each other via the branch section 30. A balloon connector 32a (see FIG. 1) is provided at the proximal end of the balloon branch pipe 32. A balloon syringe (not shown) is attached to the balloon connector 32a. A fourth lumen 24 is connected to the fourth through hole. A pressure monitor branch pipe 33 is connected to the fourth through hole. Thus, the fourth lumen 24 and the pressure monitor branch pipe 33 communicate with each other via the branch portion 30. A pressure monitor connector 33a (see FIG. 1) is provided at the proximal end of the pressure monitor branch pipe 33. The pressure monitor connector 33a is connected to a pressure measuring device (not shown). In addition, a pressure monitor cap 33b is attached to the proximal end of the pressure monitor connector 33a.

[0043] In this embodiment, by supplying myocardial protection fluid from the fluid delivery syringe to the fluid delivery connector 31a, the myocardial protection fluid can be injected into the coronary artery through the fluid delivery branch tube 31, the first through hole, the first lumen 21, the first hole portion 13a and the second hole portion 13b. 1, an opening / closing member 34 is attached to the outer circumferential surface of the fluid supply branch tube 31. By opening and closing the opening / closing member 34, it is possible to switch between supplying and stopping the cardioplegia solution. In the present embodiment, the opening / closing member 34 is, for example, a Robert clamp. However, the opening / closing member 34 is not particularly limited, and examples thereof include a roller clamp, a pinch clamp, and the like. When the opening / closing member 34 is closed, the opening / closing member 34 clamps the fluid supply branch tube 31, thereby blocking the lumen (flow path) of the fluid supply branch tube 31, and the supply of the cardioplegia solution is stopped. When the opening / closing member 34 is opened, the lumen (flow path) of the fluid supply branch tube 31 is opened, and the cardioplegia fluid is supplied.

[0044] 1, the operating section 70 is connected to the proximal end of the operating wire 50 leading out from the proximal end of the branching section 30 (the second through hole). By operating the operating section 70, the tubular body 10 can be bent.

[0045] In this embodiment, the operation unit 70 is configured to include a main body case 72 that is held by the surgeon, and a wheel operation unit 71 that is rotatably provided with respect to the main body case 72. A proximal end (not shown) of the operation wire 50 that is led out from the reinforcing tube 40 is directly or indirectly connected to the wheel operation unit 71. The proximal end of the reinforcing tube 40 may be introduced inside the main body case 72 or may be disposed outside the main body case 72 .

[0046] By rotating the wheel operating portion 71 in one direction, the operating wire 50 can be pulled toward the base end side, and the tubular body 10 can be bent in one direction. More specifically, when the wheel operating unit 71 is rotated in one direction, the flexible portion 14 of the tubular body 10 is mainly bent toward the side of the second lumen 22 through which the operating wire 50 is inserted, based on the axis of the tubular body 10.

[0047] The operating section 70 also has a holding mechanism 74 (see FIG. 1) that holds the operating wire 50 in a state where it is pulled, for example. By operating the holding mechanism 74, the bending operation of the catheter 100 is restricted, and the shape of the distal end portion 10a of the tubular body 10 is held in an extended or bent state. Thus, the catheter 100 of this embodiment further includes an operating unit 70 for bending the distal end 10a of the tubular body 10 by pulling the operating wire 50, and the operating unit 70 has a main body case 72 held by the surgeon and an operating receiver (wheel operating unit 71) to which the base end 50b of the operating wire 50 is fixed and which is pivotally supported so as to be swingable relative to the main body case 72, the pulling operation being an operation for swinging the operating receiver 75, and the operating unit 70 further includes a holding mechanism 74 for holding the distal end 10a in a bent state.

[0048] In the reinforcing tube 40 and the operating wire 50, the portion extending from the branching portion 30 to the inside of the operating portion 70 (the portion located between the branching portion 30 and the operating portion 70) is, for example, inserted into the inner cavity of a cylindrical cover member 35 (see Figure 1). The cover member 35 is formed, for example, in a tapered shape tapered toward the distal side. A base end portion of the cover member 35 is attached to a tip portion of the operation section 70.

[0049] In this embodiment, by supplying a liquid such as physiological saline from the balloon syringe to the balloon connector 32a, the liquid is injected into the balloon 60 through the balloon branch tube 32, the third through-hole, the third lumen 23, and the balloon hole 23a. This causes the balloon 60 to change from a contracted state (see FIG. 2(a)) to an expanded state (see FIG. 2(b)). Note that the liquid preferably contains, for example, a contrast agent, which allows the balloon 60 to be recognized as having expanded to a desired diameter under X-ray (radiation) observation.

[0050] The balloon connector 32a has, for example, a one-way valve (not shown) that regulates the flow of liquid from the distal side to the proximal side, thereby maintaining the balloon 60 in an inflated state.

[0051] In this embodiment, the catheter 100 is connected to a pressure measuring device through the fourth lumen 24, the pressure monitor branch tube 33, and the pressure monitor connector 33a. The pressure measuring device is used to measure and monitor the pressure within the coronary sinus with the balloon 60 inflated and deflated, respectively. The pressure measuring device is not particularly limited, but may be a transducer for detecting liquid pressure.

[0052] As shown in Figures 5(a) and 5(b), the catheter 100 of this embodiment is inserted into a vein, for example, through an introducer 110 percutaneously inserted into the vein, and further comprises a flexible sleeve 65 that is fitted around the tubular body 10 and is stretchable in the axial direction, and a cylindrical connecting portion 15 that is liquid-tightly arranged around the distal end of the sleeve 65 and is axially slidable relative to the tubular body 10, and the connecting portion 15 is detachably connectable to the introducer 110.

[0053] As shown in FIG. 1, the sleeve 65 is formed, for example, in the shape of a long hollow tube. The sleeve 65 is made of, for example, a soft resin material and can easily expand and contract in the axial direction. The soft resin material is not particularly limited, but examples thereof include soft resin materials such as polyamide, polyolefin, polyvinyl chloride, polyurethane, polyphenylene sulfide, fluororesin, and polyester.

[0054] The proximal end of the sleeve 65 is fixed in a circumferential manner and liquid-tight to the proximal end of the tubular body 10, for example, by the branching portion 30. The distal end of the sleeve 65 is fixed in a circumferential manner and liquid-tight to the connecting portion 15, and is slidable in the axial direction relative to the tubular body 10. Therefore, as the connecting portion 15 slides in the axial direction relative to the tubular body 10, the distal end of the sleeve 65 also slides relative to the tubular body 10. On the other hand, the proximal end of the sleeve 65 is fixed to the proximal end of the tubular body 10 by the branching portion 30, and is not displaced relative to the tubular body 10. More specifically, as shown in Fig. 6(a), when the connecting portion 15 slides toward the proximal side of the tubular body 10, the sleeve 65 shortens in an accordion-like manner in the axial direction. When the sleeve 65 shortens, the portion of the tubular body 10 exposed from the sleeve 65 becomes longer. On the other hand, as shown in Fig. 6(b), when the connecting portion 15 slides toward the distal side of the tubular body 10, the sleeve 65 extends in the axial direction. Furthermore, when the sleeve 65 extends, the portion of the tubular body 10 exposed from the sleeve 65 becomes shorter.

[0055] The overall length of the sleeve 65 in the most extended state is not particularly limited, but is, for example, longer than the overall length of the tubular body 10. This allows the coupling portion 15 to slide to the distal end of the tubular body 10. In other words, the entire tubular body 10 can be accommodated inside the sleeve 65.

[0056] As shown in FIGS. 6(a) and 6(b), the connecting portion 15 is, for example, a cylindrical member. The inner diameter of the connecting portion 15 is set to, for example, a dimension slightly larger than the outer diameter of the tubular body 10. This allows the connecting portion 15 to slide relative to the tubular body 10 in the axial direction.

[0057] The connecting portion 15 is formed of, for example, a hard resin material. The hard resin material is not particularly limited, but examples thereof include polyolefins such as polyethylene and polypropylene, polyamide, polycarbonate, and polystyrene. The connecting portion 15 may be integrally formed as a whole, or may be formed by combining separate members.

[0058] As shown in Figures 4 and 5, the introducer 110 comprises a tubular main body 112 through which the tubular body 10 can be inserted, and a second connecting portion 113 which is formed in a cylindrical shape through which the tubular body 10 can be inserted and which is liquid-tightly arranged around the proximal end of the tubular main body 112. In the present embodiment, the connecting portion 15 can be connected to the second connecting portion in a circumferential manner in a liquid-tight manner.

[0059] The cylindrical body 112 is formed, for example, in a long cylindrical shape. The distal end of the cylindrical body 112 is formed in a tapered shape that is slightly narrowed toward the tip side. The inner diameter of the cylindrical main body 112 is set to be larger than the outer diameter of the tubular body 10. Therefore, the tubular body 10 can be inserted into the inner cavity of the cylindrical main body 112.

[0060] The cylindrical main body 112 is made of, for example, a hard resin material. The hard resin material is not particularly limited, but examples thereof include polyolefin, polyolefin elastomer, crosslinked polyolefin, polyvinyl chloride, polyamide, polyamide elastomer, polyester, polyester elastomer, polyurethane, polyurethane elastomer, fluororesin, polycarbonate, polystyrene, polyacetal, polyimide, polyetherimide, and the like.

[0061] 4, the second connecting portion 113 is formed, for example, in a cylindrical shape. The outer diameter and the inner diameter of the second connecting portion 113 are constant, and therefore the wall thickness of the second connecting portion 113 is also constant. The inner cavity of the second connecting portion 113 is in communication with the inner cavity of the tubular main body 112 . The second connecting portion 113 has a plurality of (for example, two) protrusions 116 formed on the outer circumferential surface of the base end portion thereof, protruding radially outward. The two protruding portions 116 are formed, for example, at positions opposed to each other by 180 degrees in the circumferential direction of the second connecting portion 113.

[0062] Here, for example, the connecting portion 15 is formed with a notch 18 that is open toward the distal end side. The cutout portion 18 has, for example, a straight portion 18a and an intersecting portion 18b that are connected to each other. The straight portion 18a extends linearly from the distal end of the connecting portion 15 toward the proximal side along the axial direction. Intersection 18b extends from the proximal end of straight section 18a in a direction intersecting the extension direction of straight section 18a. Intersection 18b extends in a direction having a circumferential component and an axial component of coupling section 15, and is displaced proximally as it moves away from the proximal end of straight section 18a. In the case of this embodiment, for example, two notch shaped portions 18 are formed in the connecting portion 15. The two notch shaped portions 18 are, for example, disposed 180 degrees opposite each other in the circumferential direction of the connecting portion 15 and are rotationally symmetrical with each other.

[0063] The outer diameter of the second connecting portion 113 is set to be slightly smaller than the inner diameter of the connecting portion 15. The diameter of the protrusion 116 is equal to or slightly smaller than the width of the cutout portion 18.

[0064] To interconnect the connecting portion 15 and the second connecting portion 113, first, the second connecting portion 113 is inserted into the connecting portion 15 from the opening on the distal end side of the connecting portion 15. At this time, each of the convex portions 116 is inserted into each of the cutout portions 18 from the opening on the distal end side of the straight portion 18a of each of the cutout portions 18, and reaches the boundary between the straight portion 18a and the intersection portion 18b. Next, the connecting portion 15 and the second connecting portion 113 are rotated relatively around the axis. For example, the second connecting portion 113 is rotated in the direction of the arrow shown in Fig. 6(b). As a result, each of the protruding portions 116 is guided by the intersection portion 18b and moves to the proximal end of the intersection portion 18b (see Fig. 6(b)). This causes the connecting portion 15 and the second connecting portion 113 to be connected to each other, and restricts relative displacement of the tubular body 10 in the axial direction with respect to the cylindrical main body 112. In this manner, the introducer 110 is attached to the catheter 100. Here, as each convex portion 116 moves toward the proximal end of the intersection portion 18b, the second connecting portion 113 is inserted deeper into the connecting portion 15. During this insertion operation, it is also preferable that at least one of the outer peripheral surface of the second connecting portion 113 and the inner peripheral surface of the connecting portion 15 is formed in a tapered shape so that the second connecting portion 113 is pressed into the connecting portion 15.

[0065] Furthermore, when the connecting part 15 is connected to the second connecting part 113 (the state shown in Figure 6(b)), the connecting part 15 can be removed from the second connecting part 113 as shown in Figure 6(a) by rotating the connecting part 15 in the opposite direction of the arrow shown in Figure 6(b). 6(b), each of the protrusions 116 is guided by the intersection 18b and moves from the proximal end of the intersection 18b to the boundary between the straight portion 18a and the intersection 18b. In this state, the tubular body 10 is removed from the cylindrical main body 112 by pulling the catheter 100 proximally.

[0066] The second connecting portion 113 is made of, for example, a hard resin material. The hard resin material is not particularly limited, but examples thereof include polyolefins such as polyethylene and polypropylene, polyamide, polycarbonate, and polystyrene.

[0067] 4, the second connecting part 113 is formed with, for example, a cylindrical side port 114 that is in communication with the inner cavity of the second connecting part 113 and the inner cavity of the cylindrical main body 112. One end of a tube 114a made of, for example, a long tubular member is liquid-tightly connected to the end of the side port 114 that is not connected to the second connecting part 113. For example, a three-way stopcock 114b is attached to the other end of the tube 114a. A liquid such as physiological saline can be injected into the introducer 110 from the three-way stopcock 114b via the tube 114a.

[0068] Also, for example, a check valve (not shown) that regulates the flow of liquid from the distal end side to the proximal end side may be provided inside the second connecting part 113. By providing a check valve inside the second connecting part 113, unintended leakage of blood flowing through the biological lumen can be suppressed when the catheter 100 is removed from the introducer 110 and the biological lumen. The check valve is not particularly limited, but may be, for example, a duckbill type check valve.

[0069] Furthermore, for example, the connecting portion 15 may be provided with a lock operation portion 17 that can lock and unlock the connecting portion 15 at a desired position relative to the tubular body 10. By rotating the lock operation part 17 about its axis at a desired position in the tubular body 10, it is possible to restrict sliding of the connecting part 15 in the axial direction of the tubular body 10. In other words, it is possible to lock the insertion and removal of the tubular body 10 into and from the cylindrical main body 112.

[0070] An example of a method of using the catheter 100 of this embodiment will now be described. The following description will be given from the state in which introducer 110 has been percutaneously inserted into a vein such as the jugular vein in advance, and introducer 110 communicates between the inside and outside of a body lumen. In this state, at least the distal end of the tubular body 112 of the introducer 110 is retained inside the biological lumen, and the second connecting portion 113 provided at the proximal end of the tubular body 112 is exposed from the biological lumen. The following describes a method of inserting the distal end 10a of the tubular body 10 into the jugular vein, right atrium, and coronary sinus in that order under X-ray fluoroscopy, and delivering cardioplegia solution retrogradely to the coronary artery.

[0071] First, the distal end 10a of the tubular body 10 of the catheter 100 is inserted into the introducer 110 from an opening on the proximal end side of the introducer 110. In this state, the connecting portion 15 and the sleeve 65 are fitted to the second connecting portion 113 on the proximal side of the second connecting portion 113. Then, the connecting portion 15 and the second connecting portion 113 are rotated relatively around the axis to move each convex portion 116 from the straight portion 18a to the proximal end of the intersection portion 18b, thereby connecting the connecting portion 15 to the second connecting portion 113. In this way, the catheter 100 is attached to the introducer 110.

[0072] With the second connecting portion 113 connected to the connecting portion 15, the surgeon moves the operating portion 70 closer to the introducer 110, whereby the tubular body 10 is introduced into the jugular vein via the inner cavity of the tubular body 112. Here, since the sleeve 65 is fixed to the connecting portion 15, it is not introduced into the inner cavity of the tubular body 112 or the jugular vein, and is shortened into a bellows shape as shown in Fig. 6(b).

[0073] Next, the surgeon advances the distal end 10a of the tubular body 10 to the right atrium. Then, the surgeon pulls the operating wire 50 to bend the distal end 10a into a J-shape. Then, the surgeon torques the operating unit 70 so that the distal end of the tubular body 10 faces the desired insertion direction, i.e., toward the coronary sinus, while the distal end 10a is bent into a J-shape by pulling the operating wire 50. Furthermore, the surgeon adjusts the bending angle and pushing amount of the tubular body 10 as necessary. This allows the flexible portion 14 and the balloon 60 to be inserted into the coronary sinus. Next, the holding mechanism 74 of the operating unit 70 is operated.

[0074] Next, cardioplegic fluid is injected from a fluid-supply syringe (not shown) filled with cardioplegic fluid via the fluid-supply connector 31a. The injected cardioplegic fluid passes through the fluid-supply branch 31 and the first lumen 21, and is supplied to the coronary sinus from the holes 13 (the first hole 13a and the second hole 13b). The surgeon then inserts the flexible section 14 and the balloon 60 further into the coronary sinus while checking the fluid pressure at the distal end of the catheter 100 with a pressure measuring device. If necessary, a contrast medium is injected from a syringe (not shown) into the liquid supply connector 31a to confirm that the distal end portion 10a is inserted into the coronary sinus.

[0075] Next, a balloon syringe (not shown) filled with a liquid such as physiological saline is attached to the balloon connector 32a. The surgeon injects the liquid from the balloon syringe into the balloon connector 32a. The injected liquid passes through the balloon branch tube 32 and the third lumen 23, and is injected into the balloon 60 from the balloon hole 23a, thereby inflating the balloon 60. The inflated balloon 60 is fixed to the coronary sinus by pressing against the inner wall of the coronary sinus. This makes it possible to prevent the distal end portion 10a of the tubular body 10 from being displaced from a desired position relative to the coronary sinus. In addition, since the balloon connector 32a is provided with a one-way valve, the flow of liquid from the distal side to the proximal side is restricted when liquid is injected into the balloon 60 and when the balloon 60 is inflated. As described above, the distal end 40a of the reinforcing tube 40 is disposed proximal to the region where the balloon 60 is disposed, and the region where the balloon 60 is disposed is included in the flexible section 14. The flexible section 14 including the balloon 60 is allowed to oscillate around the proximal end of the flexible section 14 as a fulcrum. Therefore, during the process of expanding the balloon 60, the balloon 60 is autonomously adjusted to a stable posture inside the coronary sinus, and the balloon 60 fits well to the coronary vein.

[0076] Once the balloon 60 is secured to the coronary sinus, the surgeon supplies cardioplegia fluid into the coronary artery. During the injection of cardioplegia fluid, the surgeon can monitor the pressure inside the coronary sinus by checking the pressure measured by the pressure measuring device. Furthermore, the surgeon switches between supplying and stopping the cardioplegia solution by opening and closing the opening / closing member 34 depending on the situation during the procedure.

[0077] When removing the balloon 60 from the coronary vein, the balloon 60 is changed from an inflated state to a deflated state by discharging the liquid inside the balloon 60. Then, with the second connecting part 113 still connected to the connecting part 15, the operating part 70 is grasped to pull the catheter 100, and the tubular body 10 is removed from the biological lumen to the outside via the cylindrical main body 112. At this time, it is assumed that blood is attached to the portion of the tubular body 10 that was inserted into the living body. However, in the case of this embodiment, the tubular body 10 that has been removed from the living body is housed inside the sleeve 65. More specifically, the portion of the tubular body 10 that was inserted into the living body is removed from the living body and the introducer 110 while being housed inside the sleeve 65 without being exposed to the outside. Therefore, it is possible to prevent the surgeon from coming into contact with blood attached to the tubular body 10.

[0078] After removing the entire tubular body 10 from the inside of the biological lumen and the introducer 110, the surgeon releases the connection of the connecting portion 15 to the second connecting portion 113, and removes the catheter 100 from the introducer 110. As described above, since the overall length of the sleeve 65 is longer than the overall length of the tubular body 10, the tubular body 10 can be accommodated inside the sleeve 65 from the proximal end to the distal most end. Furthermore, when the connecting portion 15 is provided with the above-mentioned lock operating portion 17, the surgeon can operate the lock operating portion 17 when the connecting portion 15 is positioned near the distal end of the tubular body 10, and lock the sliding of the connecting portion 15 in the axial direction of the tubular body 10, thereby preferably maintaining the state in which the sleeve 65 and the connecting portion 15 accommodate the entire tubular body 10. Also, for example, a check valve (not shown) that regulates the flow of liquid from the proximal side to the distal side may be provided inside the connecting part 15. The check valve can prevent blood adhering to the tubular body 10 from leaking out from the opening on the distal side of the connecting part 15 to the outside.

[0079] In the above, an example has been described in which the catheter 100 is inserted into a biological lumen under X-ray fluoroscopy, but the present invention is not limited to this example, and the catheter 100 may be inserted into a biological lumen under transesophageal echocardiography in combination with a transesophageal ultrasonic endoscope.

[0080] <First Modification> Next, a first modified example of the embodiment will be described with reference to FIG. 7 to FIG. 11(f). The catheter 100 of this modified example differs from the catheter 100 of the above embodiment in the respects described below, but is otherwise configured in the same manner as the catheter 100 of the above embodiment. In the following description, the upper side (upper side) in Fig. 8(a) and Fig. 8(b) will be simply referred to as the upper side, and the lower side (lower side) in Fig. 8(a) and Fig. 8(b) will be simply referred to as the lower side. The depth direction in Fig. 8(a) and Fig. 8(b) will be referred to as the left-right direction. In the left-right direction, the near side in Fig. 8(a) and Fig. 8(b) will be referred to as the left side, and the opposite side will be referred to as the right side. In addition, in the description of the operation unit 70, the left side in Figures 8(a) and 8(b) is referred to as the distal end side, and the right side in Figures 8(a) and 8(b) is referred to as the proximal end side. Also, the direction toward the distal end side and the proximal end side is referred to as the tip-proximal end direction. However, the positional relationship of each part (particularly the vertical positional relationship) when the catheter 100 is in use is not limited to the positional relationship described in this specification.

[0081] The catheter 100 of this modified example, like the above embodiment, further includes an operating unit 70 for bending the distal end 10a of the tubular body 10 by pulling the operating wire 50, and the operating unit 70 has a main body case 72 held by the surgeon and an operating receiver 75 to which the base end 50b of the operating wire 50 is fixed and which is axially supported so as to be swingable relative to the main body case 72, and the pulling operation is an operation for swinging the operating receiver 75, and the operating unit 70 further includes a holding mechanism 74 for holding the distal end 10a in a bent state. However, in this modified example, the holding mechanism 74 of the operation unit 70 is a mechanism that holds the operation receiving unit 75 at any one of a plurality of preset swing angles. As will be described in a second modified example below, the holding mechanism 74 may be a mechanism that holds the operation receiving unit 75 at a stepless swing angle.

[0082] According to this modification, the holding mechanism 74 of the operating unit 70 can hold the operation receiving unit 75 at any one of a plurality of preset swing angles, so that the distal end 10a of the tubular body 10 can be bent at a plurality of bending angles. Therefore, the distal end 10a of the tubular body 10 can be bent by a pulling operation to selectively direct the catheter 100 in a plurality of directions, so that better operability of the catheter 100 can be realized.

[0083] The main body case 72 is a hollow member and is formed, for example, in a generally rectangular parallelepiped shape that is elongated in one direction and tapers toward the tip side. 8(a), 8(b), and 9, a sectorial section 80 (described later), a contact member 77, and a biasing section 79 are disposed inside the main body case 72. In FIG. 9, the sectorial section 80 of the internal structure of the main body case 72 is shown by a dashed line. 9, in this modified example, the main body case 72 has, for example, a first main body member 72a and a second main body member 72b, and the first main body member 72a and the second main body member 72b are assembled together to form the main body case 72. Note that the second main body member 72b is not shown in Figures 8(a), 8(b), 10(d), 10(e), and 10(f), and these figures are side views in which the internal structure can be seen. The first body member 72a and the second body member 72b are formed in a generally symmetrical shape in the left-right direction.

[0084] 8(a) and 8(b), in the case of this modification, the base end of the reinforcing tube 40 is, for example, introduced inside the main body case 72 and fixed to the main body case 72. The base end 50b of the operating wire 50 drawn out from the opening on the base end side of the reinforcing tube 40 is connected to the operation receiving portion 75. The base end 50b of the operating wire 50 is disposed along the longitudinal direction of the main body case 72, and the base end of the reinforcing tube 40 is also disposed along the longitudinal direction of the main body case 72, for example.

[0085] Here, as shown in Figures 8(a), 8(b) and 9, in this embodiment, the holding mechanism 74 has a concave-convex structure portion 76 including a plurality of concave-convex portions 76a, and an engaging portion 78 that engages with the concave-convex portions 76a among the plurality of concave-convex portions 76a of the concave-convex structure portion 76 according to the swing angle of the operation receiving portion 75. Either the uneven structure portion 76 or the fitting portion 78 is formed on the operation receiving portion 75, and the fitting portion 78 fits into any of the unevennesses 76a of the uneven structure portion 76, thereby holding the operation receiving portion 75 at any of multiple swing angle stages. More specifically, in the case of this modification, the operation unit 70 can selectively fit the fitting portion 78 into any one of the irregularities 76a of the uneven structure portion 76 by adjusting the swing angle of the operation receiving portion 75 by a pulling operation. Therefore, when the pulling operation is released, the operation receiving portion 75 can be held at the swing angle when the pulling operation is released. This improves the operability of the catheter 100.

[0086] In the present modified example, as an example, a concave-convex structure 76 is formed in the operation receiving portion 75, and the holding mechanism 74 has a contact member 77 including an engaging portion 78, and a biasing portion 79 that biases the contact member 77 so that the engaging portion 78 is pressed against the operation receiving portion 75. As a result, in a state in which the fitting portion 78 is fitted into any of the concaves and convexes 76a of the concave-convex structure portion 76, the fitting portion 78 is biased by the biasing portion 79 to be pressed against the operation receiving portion 75. Therefore, when the towing operation is released, the operation receiving portion 75 can be more reliably held at the swing angle when the towing operation was released.

[0087] 11(a) to 11(f), the operation receiving portion 75 has, for example, a sector portion 80 formed in a sector shape, and is pivotally supported so as to be swingable in the circumferential direction of the sector portion 80, and a plurality of projections and recesses 76a are arranged in the circumferential direction of the arc-shaped peripheral surface 80a of the sector portion 80. In other words, the projection-recess structure portion 76 is formed on the peripheral surface 80a of the sector portion 80. This allows the uneven structure 76 to be formed on the peripheral surface 80a with a larger radius of curvature, and allows the operation receiving portion 75 to be housed in the compact main body case 72. Furthermore, with a smaller swing angle of the operation receiving portion 75, a sufficient distance of pulling operation can be performed, and the bending angle range of the distal end portion 10a can be satisfactorily secured. Fig. 11(b) is a plan view of the sector portion 80 when the swing angle of the operation receiving portion 75 is the angle shown in Fig. 8(a), and Fig. 11(c) is a bottom view of the sector portion 80 when the swing angle of the operation receiving portion 75 is the angle shown in Fig. 8(a). Also, Figs. 11(d) to 11(f) show a third shaft member 88, which will be described later. In the following description, the circumferential direction of the peripheral surface 80a of the sector-shaped portion 80 may be simply referred to as the circumferential direction.

[0088] The sector portion 80 is formed, for example, in a sector shape in side view. More specifically, the sector portion 80 has a plate-shaped portion 81b formed in a sector shape in side view, an arc-shaped peripheral wall portion 81a disposed along the arc-shaped peripheral edge portion of the plate-shaped portion 81b, and a first wall portion 81c and a second wall portion 81d each extending in the radial direction of the sector portion 80. The assembly of the peripheral wall portion 81a, the first wall portion 81c and the second wall portion 81d forms a fan-shaped frame body in a side view, and the plate-shaped portion 81b is a plate-shaped portion formed in the same shape as the frame body and is arranged inside the frame body. More specifically, the plate-shaped portion 81b is formed in a flat plate shape. The plate-shaped portion 81b is disposed with each plate surface facing in the left-right direction. Here, the plate-like portion 81b has side edges extending in the radial direction on both circumferential side edges of the plate-like portion 81b. Of these edges, a first wall portion 81c is disposed along the edge on the tip end side, and a second wall portion 81d is disposed along the edge on the base end side. The first wall portion 81c and the second wall portion 81d are each formed in a flat plate shape. The first wall portion 81c and the second wall portion 81d are disposed such that their respective plate surfaces face in the circumferential direction of the sector portion 80. The peripheral wall portion 81a, the first wall portion 81c, and the second wall portion 81d stand upright in the left-right direction from the plate-shaped portion 81b. The peripheral wall portion 81a, the first wall portion 81c, and the second wall portion 81d have the same left-right width dimensions. Further, the radially outer end of the first wall portion 81c is connected to the tip end of the peripheral wall portion 81a, and the radially outer end of the second wall portion 81d is connected to the base end of the peripheral wall portion 81a. Further, the radially inner end of the first wall portion 81c and the radially inner end of the second wall portion 81d are connected to each other. Therefore, the angle between the first wall portion 81c and the second wall portion 81d is the central angle of the sector portion 80 in side view. The central angle of the sectoral portion 80 is not particularly limited, but is preferably 70 degrees or more and 170 degrees or less, and more preferably 90 degrees or more and 150 degrees or less. In addition, in the peripheral wall portion 81a, the first wall portion 81c side is the tip end side, and the second wall portion 81d side is the base end side. Inside the main body case 72, the sector portion 80 is supported in such a manner that the peripheral surface 80a faces upward and the oscillation axis of the sector portion 80 faces downward.

[0089] In this modified example, the sector portion 80 is pivotally supported at the center of the sector portion 80 (near the connection between the first wall portion 81c and the second wall portion 81d). The swing axis of the sector portion 80 extends in the left-right direction. Therefore, the operation receiving portion 75 can swing, for example, in one direction in the circumferential direction of the peripheral surface 80a of the sector portion 80 and in the opposite direction in the circumferential direction of the peripheral surface 80a of the sector portion 80. The swing axis of the sector portion 80 is perpendicular to the longitudinal direction of the main body case 72, i.e., a direction including a component in the tip-proximal direction. Therefore, the swing direction of the sector portion 80, i.e., the swing direction of the operation receiving portion 75, is a direction including a component in the tip-proximal direction, and the pulling direction of the operating wire 50 is also a direction including a component in the tip-proximal direction. In this modified example, by swinging the operation receiving portion 75 in one circumferential direction, the operation wire 50 can be pulled toward the base end side to apply tension. Also, by swinging the operation receiving portion 75 in the opposite circumferential direction, the operation wire 50 can be moved toward the tip end side to be relaxed. In this manner, the distal end portion 10a of the tubular body 10 can be bent or stretched.

[0090] More specifically, as shown in Figs. 8(a) and 8(b), a first shaft hole 85 is formed in the center of the sector portion 80, penetrating the sector portion 80 in the left-right direction. Furthermore, a holding portion (not shown) is formed in each of the inner surfaces of the first main body member 72a and the second main body member 72b at a location facing the first shaft hole 85. The holding portion has a holding hole arranged coaxially with the first shaft hole 85. A first shaft member 86 formed in a rod shape long in the left-right direction is inserted from one holding hole through the first shaft hole 85 to the other holding hole. In this way, the sector portion 80 is supported by the first shaft member 86.

[0091] 11(e) and 11(f), a void 95 is formed in the plate-shaped portion 81b. The void 95 is formed over the entire plate-shaped portion 81b in the thickness direction. The void 95 extends in the circumferential direction along the peripheral wall portion 81a. In addition, in the portions of the plate-shaped portion 81b corresponding to the blank spaces 95, for example, second plate-shaped portions 87a and 87b are disposed. The second plate-shaped portions 87a and 87b are each formed in a flat plate shape. The plate surfaces of the second plate-shaped portions 87a and 87b are disposed facing the left-right direction. The second plate-shaped portions 87a and 87b are disposed opposite each other. The left side surface of the second plate-shaped portion 87a is disposed on the same plane as the right side surface of the plate-shaped portion 81b. The right side surface of the second plate-shaped portion 87b is disposed on the same plane as the left side surface of the plate-shaped portion 81b. The second plate-shaped portion 87a closes the gap 95 from the right side. The second plate-shaped portion 87b closes the base end side end of the gap 95 from the left side, and the portion of the gap 95 on the tip side of the second plate-shaped portion 87b opens toward the left side. Furthermore, the second plate-shaped portions 87a and 87b are provided with cylindrical portions 84a and 84b, respectively (see Figs. 11(e) and 11(f)). The cylindrical portion 84a provided on the second plate-shaped portion 87a protrudes toward the first main body member 72a, and the cylindrical portion 84b provided on the second plate-shaped portion 87b protrudes toward the second main body member 72b. The cylindrical portions 84a, 84b are formed symmetrically with respect to the axis of the main body case 72. The cylindrical portions 84a, 84b are each formed cylindrically, and their axial direction is parallel to the pivot axis of the operation receiving portion 75. The cylindrical portions 84a, 84b are also arranged coaxially with each other. The second plate-shaped portion 87a has a through hole arranged coaxially with the cylindrical portion 84a, and the second plate-shaped portion 87b has a through hole arranged coaxially with the cylindrical portion 84b. Here, one third shaft member 88 formed in a rod shape long in the left-right direction is inserted from the inner cavity of the cylindrical portion 84a through the second shaft hole portion 77d to the inner cavity of the cylindrical portion 84b. The inner cavity of each of the cylindrical portions 84a, 84b communicates with the space 95 via the through-holes of the second plate-like portions 87a, 87b, and the central portion in the longitudinal direction of the third shaft member 88 is disposed inside the space 95. The base end portion 50b of the operating wire 50 is connected to the central portion of the third shaft member 88. More specifically, the base end of the operating wire 50 is a ring-shaped hook portion 51, and the base end portion 50b of the operating wire 50 is connected to the operating receiving portion 75 by engaging the hook portion 51 with the third shaft member 88. When the operation receiving portion 75 swings, the third shaft member 88 swings in an arc shape around the first shaft member 86, and the base end portion 50b of the operating wire 50 is pulled along with the third shaft member 88 in an arc shape path.

[0092] As shown in FIGS. 11(a), 11(b) and 11(c), a slit portion 83a is formed between the peripheral wall portion 81a and the first wall portion 81c. In this modified example, the slit portion 83a is connected to the space 95, and the base end portion 50b of the operating wire 50 pulled out from the opening on the base end side of the reinforcing tube 40 is guided to the third axis member 88 in the space 95, for example, via the slit portion 83a. The shape and dimensions of the slit portion 83a are set so that the sector portion 80 and the base end portion 50b of the operating wire 50 do not interfere with each other regardless of the angle of the operation receiving portion 75. More specifically, a portion of the slit portion 83a is formed, for example, in a portion on the tip side of the circumferential surface 80a, and the remaining portion of the slit portion 83a is formed in a portion on the tip side of the first wall portion 81c. In the slit portion 83a, a portion formed in the peripheral wall portion 81a extends in the circumferential direction and penetrates the peripheral wall portion 81a in the radial direction of the sector portion 80. In addition, in the slit portion 83a, a portion formed in the first wall portion 81c extends in the radial direction of the sector portion 80 and penetrates the first wall portion 81c in the circumferential direction of the sector portion 80.

[0093] In this modified example, the outer peripheral surface of the peripheral wall portion 81a constitutes the peripheral surface 80a. That is, the peripheral wall portion 81a is formed with an uneven structure 76 including a plurality of unevennesses 76a. More specifically, the concave-convex structure 76 is formed on a base end side portion of the circumferential surface 80a. The multiple concave-convex structures 76a are disposed adjacent to one another in the circumferential direction. Each of the concave portions of the multiple irregularities 76a is formed concavely toward the radially inward direction of the sector portion 80, and each of the convex portions of the multiple irregularities 76a is formed convexly toward the radially outward direction of the sector portion 80. In the present modified example, as an example, the number of the projections and recesses 76a is 7. Therefore, the operation receiving portion 75 is held at any one of the seven swing angles, and the bending angle of the tubular body 10 is also held at any one of the seven bending angles. However, the number of projections and recesses 76a is not particularly limited, and can be set appropriately according to the desired number of stages of the swing angle.

[0094] Here, a recess is disposed at the tip of the plurality of projections and recesses 76a, and the bottom surface of the recess constitutes, for example, a sliding portion 75a (see FIG. 8(b) and the like) along which the fitting portion 78 slides without fitting into a fixed position. In addition, the remaining projections and recesses 76a (hereinafter may be simply referred to as the remaining projections and recesses 76a) of the plurality of projections and recesses 76a, excluding the recess in which the sliding portion 75a is formed, are formed in the same shape as one another, and are arranged, for example, in the order of projections and recesses, alternating from the tip side. More specifically, in the circumferential direction, the length dimension of the recess in which the sliding portion 75a is formed is greater than the length dimension of each recess in the remaining irregularities 76a. The sliding portion 75a is an arc-shaped smooth curved surface centered on the pivot axis of the operation receiving portion 75 as a whole. Therefore, the sliding portion 75a has the same distance from the pivot axis regardless of its position in the circumferential direction. In addition, the formation depth of the recess in which the sliding portion 75a is formed is greater than the formation depth of each recess in the remaining irregularities 76a. That is, the position of the sliding portion 75a is closer to the axis of the sector portion 80 than the deepest part of each recess in the remaining irregularities 76a. In addition, the inclination of the convex portion defining the recess in which the sliding portion 75a is formed is greater (steeper) than the inclination of each convex portion in the remaining irregularities 76a. Moreover, each of the recesses of the remaining irregularities 76a is arc-shaped in side view. In the present modified example, such approximately arc-shaped recesses are arranged in a row, and the boundaries between the recesses are convex portions. Therefore, each of the protrusions of the remaining irregularities 76a is tapered toward the tip side (the tip side in the protruding direction of the protrusions) in side view. In the present modified example, the portion between the apex of one protrusion and the apex of the next protrusion in the remaining irregularities 76a is a concave portion. In addition, in the remaining irregularities 76a, the dimensions of each protrusion are equal to each other, and the distance from the oscillation axis of the sector portion 80 to the apex of each protrusion is equal to each other. 9, each of the recesses of the plurality of irregularities 76a is formed, for example, as a groove extending along the oscillation axis of the sector-shaped portion 80. That is, each recess is a curved surface recessed toward the center. Therefore, each of the protrusions is a ridge extending along the oscillation axis of the sector-shaped portion 80.

[0095] The sector portion 80 is integrally molded as a whole from, for example, a hard resin material. Examples of the hard resin material include, but are not limited to, polyolefins such as polyethylene and polypropylene, polyamides, polycarbonates, polystyrene, and acrylonitrile butadiene styrene copolymers. It should be noted that the sector-shaped portion 80 may be formed, for example, by combining separate members.

[0096] As shown in FIGS. 8(a) and 8(b), in this modified example, a contact member 77 is pivotally supported relative to the main body case 72 so as to be able to swing. More specifically, the abutting member 77 is formed with a second shaft hole portion 77d penetrating the abutting member 77 in the left-right direction. Also, a second retaining portion (not shown) is formed on each of the inner surfaces of the first main body member 72a and the second main body member 72b at a location facing the second shaft hole portion 77d. Each second retaining portion has a second retaining hole arranged coaxially with the second shaft hole portion 77d. One second shaft member 721c formed in a rod shape long in the left-right direction is inserted from one second retaining hole through the second shaft hole portion 77d to the other second retaining hole. In this way, the abutment member 77 is able to swing around the axis of the second shaft member 721c. Therefore, the swing direction of the abutment member 77 coincides with the swing direction of the operation receiving portion 75. Note that, inside the main body case 72, the position of the swing axis of the abutment member 77 is disposed, for example, on the base end side of the swing axis of the operation receiving portion 75. Also, the swing region of the abutment member 77 is disposed, for example, on the base end side of the swing region of the operation receiving portion 75.

[0097] Here, in the contact member 77, a fitting portion 78 is formed at a portion facing the plurality of projections and recesses 76a. Further, in the abutting member 77, a biasing portion 79 acts on the surface opposite to the side on which the fitting portion 78 is formed. In this modified example, the biasing portion 79 is, for example, a coil spring. Here, inside the main body case 72, a housing portion 89 for housing the biasing portion 79 is formed. More specifically, three plate-shaped portions are formed on the inner surface of the first main body member 72a and arranged in a U-shape in side view (a U-shape opening toward the sector portion 80). Each plate-shaped portion stands up from a portion of the inner surface of the first main body member 72a facing the second main body member 72b toward the second main body member 72b. The three plate-shaped portions include a pair of first plate-shaped portions 89a arranged parallel to each other, and a second plate-shaped portion 89b connecting the ends of the pair of first plate-shaped portions 89a. The accommodation portion 89 is defined by a pair of first plate-shaped portions 89a, a second plate-shaped portion 89b, an inner side surface of the first main body member 72a, and an inner side surface of the second main body member 72b. The biasing portion 79 is disposed, for example, inside the accommodation portion 89. The urging portion 79 is sandwiched between the second plate-shaped portion 89b and the abutment member 77, and urges the abutment member 77 toward the peripheral surface 80a of the sector-shaped portion 80. More specifically, one end of the urging portion 79 abuts against the abutment member 77, and the other end of the urging portion 79 abuts against the second plate-shaped portion 89b. The pair of first plate-shaped portions 89a guide the expansion and contraction of the urging portion 79 in the axial direction. Further, a cylindrical protrusion 77a is formed on the surface of the abutting member 77 on which the urging portion 79 acts so as to prevent the coil spring from shifting, and the urging portion 79 is fitted onto the protrusion 77a. Thus, in this modified example, the holding mechanism 74 has a contact member 77 including a fitting portion 78 and a biasing portion 79 that biases the contact member 77 so that the fitting portion 78 is pressed against the operation receiving portion 75.

[0098] The contact member 77 is integrally molded as a whole from, for example, a hard resin material. Examples of the hard resin material include, but are not limited to, polyolefins such as polyethylene and polypropylene, polyamide, polycarbonate, polystyrene, and acrylonitrile butadiene styrene copolymers. The contact member 77 may be formed, for example, by combining separate members.

[0099] As shown in FIGS. 8(a) and 8(b), the contact member 77 is formed, for example, in the shape of a plate bent into a dogleg shape (an L-shape with an obtuse central angle) when viewed from the side. More specifically, the abutting member 77 has a tip side portion 77b in which the fitting portion 78 is formed, and a base side portion 77c connected to the tip side portion 77b. The distal end portion 77b and the proximal end portion 77c are each formed in a flat plate shape, with the plate surfaces of the distal end portion 77b and the proximal end portion 77c being disposed along the left-right direction. In the tip side portion 77b, a fitting portion 78 is formed on a surface facing the multiple projections and recesses 76a, and a protrusion portion 77a is formed on the opposite surface, against which a biasing portion 79 abuts. A second shaft hole portion 77d is formed in the center of the base side portion 77c (the center in the extending direction of the base side portion 77c). The fitting portion 78 is formed, for example, in a cylindrical shape protruding from the tip side portion 77b toward the unevenness 76a. The protruding direction of the fitting portion 78 is, for example, approximately the same as the radial direction of the sector portion 80. Moreover, the protruding portion 77a protrudes in a direction opposite to the protruding direction of the fitting portion 78. A tip end portion of the protruding portion 77a (a tip end portion of the protruding portion 77a in the protruding direction) is disposed inside the accommodation portion 89, for example. In the case of this modified example, the biasing direction of the biasing portion 79 is, for example, approximately the same as the protruding direction of the fitting portion 78 .

[0100] The biasing portion 79 biases the tip portion 77b toward the peripheral surface 80a of the sector-shaped portion 80, so that at least a portion of the tip surface 78a of the fitting portion 78 abuts against the peripheral surface 80a. More specifically, depending on the pivot angle of the operation receiving portion 75, the tip surface 78a of the fitting portion 78 abuts against either the concave-convex structure portion 76 or the sliding portion 75a. As shown in FIG. 8(a), the operation receiving portion 75 is urged by the urging portion 79 so that the fitting portion 78 fits into one of the projections and recesses 76a, thereby restricting the swinging of the operation receiving portion 75. By swinging the operation receiving portion 75, the engagement of the engagement portion 78 with the corresponding concave-convex portion 76a can be released, and the engagement portion 78 can be engaged with another concave-convex portion 76a or moved onto the sliding portion 75a. More specifically, the circumferential dimension of each recess of the multiple projections and recesses 76a is set to, for example, a dimension that is approximately equal to the diameter of the fitting portion 78. Therefore, the fitting portion 78 fits well with the projections and recesses 76a. Furthermore, as shown in FIG. 8(b), in a state in which the tip surface 78a of the fitting portion 78 abuts against the sliding portion 75a, the operation receiving portion 75 is not held at any angle among the multiple swing angles. More specifically, the length of the sliding portion 75a is set to be, for example, larger than the diameter of the fitting portion 78. Therefore, the fitting portion 78 is displaceable with respect to the operation receiving portion 75 in a state in which the fitting portion 78 is in contact with the sliding portion 75a. As described above, the depth of the recess in which the sliding portion 75a is formed is greater than the depth of each recess in the remaining irregularities 76a. Therefore, in a state in which the fitting portion 78 abuts against the sliding portion 75a, compared to a state in which the fitting portion 78 abuts against the remaining irregularities 76a, the biasing portion 79 is in a state in which it extends further in the axial direction, and the biasing force of the biasing portion 79 is smaller. Therefore, the operation receiving portion 75 can easily swing. It is to be noted that the operation receiving portion 75 does not have to have, for example, the sliding portion 75a. In this case, the multiple projections and recesses 76a have, for example, the same shape as each other.

[0101] Here, a protrusion 82 that receives a pulling operation is formed on the peripheral surface 80a. As an example, the protrusion 82 is formed on a portion on the tip side of the region where the plurality of irregularities 76a are formed. The protrusion 82 (see Figs. 9 and 11(a)) is formed protruding outward in the radial direction of the sector portion 80. The tip portion 82a of the protrusion 82 (the tip portion in the extension direction of the protrusion 82) is formed, for example, to be wider in the circumferential direction than the base portion 82b of the protrusion 82 (the base portion in the extension direction of the protrusion 82) and tapers toward the tip side.

[0102] Furthermore, an opening 73 (see FIG. 9 and the like) is formed at the upper end of the main body case 72, which communicates the internal space of the main body case 72 with the outside of the main body case 72. The opening 73 is formed, for example, in a substantially rectangular shape that is long in the longitudinal direction of the main body case 72 in a plan view. A tip 82a of the protrusion 82 protrudes to the outside of the main body case 72 through the opening 73. For example, while holding the main body case 72 with one hand, the surgeon can swing the tip 82a in the circumferential direction with the fingers of the hand holding the main body case 72, thereby swinging the operation receiving portion 75. That is, the surgeon can easily perform the traction operation while holding the main body case 72 with one hand. More specifically, for example, the operating unit 70 has a structure suitable for operating the protruding portion 82 with the first finger while gripping the lower portion of the main body case 72 with the second finger to the fifth finger and the palm. The finger that operates the protruding portion 82 is not particularly limited, and may be the second finger, etc.

[0103] In addition, in the case of this modified example, the range of the pivot angle of the protruding portion 82 is limited by the opening 73, and therefore the range of the pivot angle of the operation receiving portion 75 is limited. More specifically, the protrusion 82 is movable within an angular range from a position where the base end 82b of the protrusion 82 abuts against the edge of the tip end of the opening 73 (see FIG. 8(a)) to a position where the base end 82b of the protrusion 82 abuts against the edge of the base end of the opening 73 (see FIG. 8(b)). Therefore, the operation receiving portion 75 is swingable within an angular range from the edge of the tip end of the opening 73 to the edge of the base end of the opening 73. In addition, by limiting the range of the swing angle of the operation receiving portion 75, the fitting portion 78 does not come into contact with the region of the circumferential surface 80a that is closer to the tip side than the sliding portion 75a, and is prevented from climbing over the protruding portion disposed at the most proximal end side (preventing the fitting portion 78 from falling off to the proximal end side). In other words, at any swing angle of the operation receiving portion 75, the fitting portion 78 comes into contact with either the sliding portion 75a or the uneven structure portion 76.

[0104] In the case of this modification, the operating wire 50 can be pulled toward the base end side and tensioned by swinging the protruding portion 82 in a direction approaching the edge on the base end side of the opening 73. Also, the operating wire 50 can be moved toward the tip side and relaxed by swinging the protruding portion 82 in a direction approaching the edge on the tip end side of the opening 73. In this manner, the distal end portion 10a of the tubular body 10 can be bent or stretched.

[0105] 10(a) and 10(d), for example, the distal end 10a of the tubular body 10 is extended (not bent) when the base end 82b of the protrusion 82 is in contact with the edge of the tip side of the opening 73. Also, the fitting portion 78 is fitted into the irregularity 76a located at the most base end side. 10(b) and 10(e), when the protruding portion 82 is swung toward the base end side from the state shown in Fig. 10(a), the base end portion 50b of the operating wire 50 is pulled toward the base end side, and the distal end portion 10a of the tubular body 10 is bent toward the second lumen 22 side through which the operating wire 50 is inserted, with the axis of the tubular body 10 as a reference. Also, the fitting portion 78 is pressed by the operation receiving portion 75 and swings in the opposite direction to the swinging direction of the operation receiving portion 75, and fits into any of the irregularities 76a that are located further distal than the irregularities 76a located closest to the base end. Next, when the operation receiving portion 75 is further swung in a direction approaching the edge portion on the base end side of the opening 73 from the state shown in FIG. 10(b) as shown in FIG. 10(c) and FIG. 10(f), the base end portion 50b of the operating wire 50 is further pulled toward the base end side, and the distal end portion 10a of the tubular body 10 is bent at a larger bending angle toward the second lumen 22 side through which the operating wire 50 is inserted, based on the axis of the tubular body 10. Also, the fitting portion 78 is fitted into any of the irregularities 76a arranged on the more distal end side. Then, when the operation receiving portion 75 is swung to a position where the base end portion 82b abuts against or is close to the edge portion on the base end side of the opening 73, the fitting of the fitting portion 78 with the irregularities 76a is released, and the fitting portion 78 abuts against the sliding portion 75a arranged on the distal end side of the uneven structure portion 76. On the other hand, when the operation receiving portion 75 is swung in a direction approaching the edge on the tip side of the opening 73, the base end portion 50b moves toward the tip side, so that the operation wire 50 relaxes and the bending angle of the distal end portion 10a becomes smaller. Then, as shown in Figures 10(a) and 10(d), when the operation receiving portion 75 is swung in one direction until the protruding portion 82 abuts against the edge on the tip side of the opening 73, the distal end portion 10a of the tubular body 10 is extended. That is, by swinging the operation receiving portion 75 in the other direction until the protruding portion 82 abuts against the front end portion of the opening 73, the bent state of the distal end portion 10a of the tubular body 10 can be released. In this way, by operating the operating portion 75 of the operating unit 70 to pull or relax the operating wire 50, the distal end 10a of the tubular body 10 can be selectively bent in multiple directions that are all contained in the same plane.

[0106] The range of the swing angle of the operation receiving portion 75 is not particularly limited, but is preferably set to, for example, 20 degrees or more and 60 degrees or less, and more preferably, 30 degrees or more and 50 degrees or less. By setting the range of the swing angle of the operation receiving portion 75 to 20 degrees or more, the range of the bending angle of the distal end portion 10a of the tubular body 10 can be sufficiently secured. By setting the range of the swing angle of the operation receiving unit 75 to 60 degrees or less, the operation receiving unit 75 can be easily swung from the minimum swing angle to the maximum swing angle with the fingers of the hand holding the operation unit 70 while maintaining the state in which the operation unit 70 is held in one hand.

[0107] <Second Modification> Next, a second modified example of the embodiment will be described with reference to FIGS. 12(a) and 12(b). The catheter 100 according to the second modification differs from the catheter 100 according to the first modification in the points described below, and is otherwise configured similarly to the catheter 100 according to the first modification. Note that the second body member 72b is not shown in Figures 12(a) and 12(b).

[0108] The holding mechanism 74 in this modified example is, for example, a mechanism for holding the operation receiving portion 75 at a stepless swing angle. As a result, the holding mechanism 74 of the operating unit 70 can hold the operation receiving unit 75 at any angle of the stepless swing angle, so that the distal end portion 10a of the tubular body 10 can be adjusted to a stepless bending angle. This allows the bending angle of the distal end portion 10a to be adjusted more finely.

[0109] In this manner, the catheter 100 according to this modified example further includes an operating unit 70 for bending the distal end 10a of the tubular body 10 by pulling the operating wire 50, and the operating unit 70 includes a main body case 72 that is held by the surgeon, and an operating receiver 75 to which the base end 50b of the operating wire 50 is fixed and which is pivotally supported so as to be swingable relative to the main body case 72, and the pulling operation is an operation for swinging the operating receiver 75, and the operating unit 70 further includes a holding mechanism 74 that holds the distal end 10a in a bent state, and the holding mechanism 74 is a mechanism that holds the operating receiver 75 at a stepless swing angle.

[0110] In the present modified example, as shown in Figures 12(a) and 12(b), the holding mechanism 74 has a friction portion 91 and a pressure contact portion 92 that is pressed against the friction portion 91, and the operation receiving portion 75 is held at any angle of a stepless swing angle by the pressure contact portion 92 being pressed against the friction portion 91. More specifically, the operation section 70 is configured such that, for example, when a traction operation is performed, the pressure contact portion 92 is pressed against any region of the friction portion 91. In this state, the rocking of the operation receiving section 75 is restricted by the pressure contact portion 92. Therefore, when the traction operation is released, the operation receiving section 75 can be held at the rocking angle at which the traction operation was released without performing another operation. This improves the operability of the catheter 100. In the case of this modified example, the pressure contact portion 92 can be pressure-contacted with any region of the friction portion 91. Therefore, the operation receiving portion 75 can be held at a stepless swing angle. More specifically, in a state in which the pressure-contact portion 92 is in pressure contact with the friction portion 91, a tip corner of a tip surface 92a of the pressure-contact portion 92 bites into the friction portion 91, for example.

[0111] In this modification, a friction portion 91 is provided on the arc-shaped peripheral surface 80a of the sector portion 80 instead of the concave-convex structure portion 76. Similarly to the first modification, a sliding portion 93 is provided on the peripheral surface 80a. In the present modified example, the frictional force generated between the friction portion 91 and the pressure-contact portion 92 is greater than the frictional force generated between the sliding portion 93 and the pressure-contact portion 92. When the pressure-contact portion 92 is in pressure contact with any region of the friction portion 91, the swinging of the operation receiving portion 75 is restricted, and the operation receiving portion 75 is held at any angle of the stepless swinging angle. When the pressure-contact portion 92 is in pressure contact with the sliding portion 93, the swinging of the operation receiving portion 75 is not restricted. The sliding portion 93 has a structure similar to that of the sliding portion 75a in the first modified example, for example. That is, a recess recessed toward the inside in the radial direction of the sector portion 80 is formed in the portion of the circumferential surface 80a closer to the base end than the friction portion 91, and the bottom surface of the recess constitutes the sliding portion 93. In addition, the pressure contact portion 92 also has the same structure as, for example, the fitting portion 78 in the first modified example. Therefore, the pressure contact portion 92 is biased by the biasing portion 79 and is pressed against the operation receiving portion 75. In addition, by performing a pulling operation, the position of the friction portion 91 relative to the pressure contact portion 92 can be changed, and the swing angle of the operation receiving portion 75 can be changed.

[0112] The friction portion 91 is formed, for example, by attaching a sheet material made of a material having a larger friction coefficient than the resin material that makes up the sector-shaped portion 80 described above. Such a material is not particularly limited, but may be a rubber material such as polyurethane elastomer, polyamide elastomer, silicone rubber, or latex rubber. However, the friction portion 91 may be, for example, a rough surface on which a plurality of minute projections and recesses are formed.

[0113] Although the embodiments have been described above with reference to the drawings, these are merely examples of the present invention, and various configurations other than those described above can also be adopted.

[0114] For example, in the above description, an example has been described in which the inner wall of the tubular body 10 defines multiple lumens 20, but the present invention is not limited to this example, and multiple tubes may be embedded inside the tubular body 10, and the inner walls of the multiple tubes may define multiple lumens 20, respectively.

[0115] In the first modified example, the uneven structure 76 is formed on the operation receiving portion 75, but, for example, the uneven structure 76 may be formed on the inner surface of the main body case 72. In this case, for example, a fitting portion 78 is provided on the plate-shaped portion 81b of the sector portion 80 (operation receiving portion 75), and the fitting portion 78 fits into the uneven structure 76, so that the swing angle of the operation receiving portion 75 is maintained within a predetermined angle range.

[0116] Also, for example, in the second modified example, an example has been described in which the swinging of operation receiving portion 75 is restricted by friction between friction portion 91 disposed on operation receiving portion 75 and pressure contact portion 92 included in abutment member 77. However, the present invention is not limited to this example, and the swinging of operation receiving portion 75 may be restricted by friction between operation receiving portion 75 and the inner surface of main body case 72. More specifically, for example, a friction portion 91 may be formed on the sector portion 80 and a pressure contact portion 92 may be formed on the inner surface of the main body case 72, or a pressure contact portion 92 may be formed on the sector portion 80 and a friction portion 91 may be formed on the inner surface of the main body case 72. When the friction portion 91 is formed on the inner surface of the main body case 72, the pressure contact portion 92 is preferably formed, for example, on the side surface of the sector portion 80. Also, it is preferable that the inner surface of the main body case 72 is respectively formed, for example, with a thin portion having a relatively small thickness in the left-right direction and a thick portion having a relatively large thickness in the left-right direction. The thin portion and the thick portion allow switching between a state in which the pressure contact portion 92 is in pressure contact with the friction portion 91 and a state in which the pressure contact portion 92 is not in pressure contact with the friction portion 91. In addition, the thin portion and the thick portion may be formed in the sector portion 80 . Furthermore, it is also preferable that a protruding region that protrudes relatively toward the sector portion 80 and a non-protruding region where the protruding region is not formed are formed on the inner side of the main body case 72. The protruding region and the non-protruding region make it possible to switch between a state in which the pressure contact portion 92 is in pressure contact with the friction portion 91 and a state in which the pressure contact portion 92 is not in pressure contact with the friction portion 91. The protruding regions and the non-protruding regions may each be formed in the sector portion 80 .

[0117] Also, for example, in the second modified example, an example has been described in which the swinging of operation receiving portion 75 is restricted by friction between friction portion 91 disposed on operation receiving portion 75 and pressure contact portion 92 included in abutment member 77. However, the present invention is not limited to this example, and the swinging of operation receiving portion 75 may be restricted by friction between sector portion 80 and first shaft member 86 supporting sector portion 80. More specifically, for example, the swinging of the operation receiving portion 75 may be restricted by friction between a first shaft member 86 that pivotally supports the sector portion 80 and a first shaft hole portion 85 of the sector portion 80. In this case, a friction portion 91 may be formed on the first shaft member 86 and a pressure contact portion 92 may be formed on the inner circumferential surface of the first shaft hole portion 85, or a pressure contact portion 92 may be formed on the first shaft member 86 and a friction portion 91 may be formed on the inner circumferential surface of the first shaft hole portion 85. Furthermore, for example, the swinging of the operation receiving portion 75 may be restricted by friction between the first shaft member 86 and a holding portion formed on the main body case 72. In this case, the friction portion 91 may be formed on the holding portion and the pressure contact portion 92 may be formed on the first shaft member 86, or the pressure contact portion 92 may be formed on the holding portion and the friction portion 91 may be formed on the first shaft member 86.

[0118] Also, for example, in the first and second modified examples, an example has been described in which the range of the angle of swing of operation receiving portion 75 is restricted by protruding portion 82 abutting against the tip or base end of opening 73. However, the present invention is not limited to this example, and the swing of operation receiving portion 75 may be configured such that the range of the angle of swing of operation receiving portion 75 is restricted by, for example, a convex portion (not shown) formed on the inner surface of main body case 72 abutting against operation receiving portion 75.

[0119] The present embodiment encompasses the following technical ideas. (1) A catheter that is placed in the coronary sinus of the heart to supply cardioplegia to the coronary arteries, A tubular body having a plurality of lumens; a hole for supplying the cardioplegia solution formed at a distal end of the tubular body and communicating with the first lumen; A reinforcing tube inserted into the second lumen; An operating wire inserted through the reinforcing tube; having the stiffening tube extends from the proximal end of the tubular body to the distal end, A catheter in which the tip of the operating wire is led out from the distal end of the reinforcing tube and fixed to the distal end of the tubular body distal to the distal end of the reinforcing tube. (2) a balloon provided on the outer periphery of the distal end of the tubular body and communicating with the third lumen; The catheter according to (1), wherein the reinforcing tube extends from the proximal side of the tubular body to a region near the proximal side of the balloon placement region. (3) A catheter according to (2), wherein the distal end of the reinforcing tube is positioned proximal to the placement area of ​​the balloon. (4) A catheter described in any one of (1) to (3), having as the hole a first hole formed in the distal end of the tubular body and a second hole formed on the circumferential surface of the distal end of the tubular body. (5) The catheter is inserted into a vein through an introducer that is percutaneously inserted into the vein; a flexible sleeve that is inserted around the tubular body and is expandable and contractible in the axial direction; a cylindrical coupling portion that is circumferentially and fluid-tightly provided on the distal end portion of the sleeve and is axially slidable relative to the tubular body; Further comprising: A catheter described in any one of (1) to (4), wherein the connecting portion is detachably connectable to the introducer. (6) Further comprising an operating unit for bending the distal end portion of the tubular body by pulling the operating wire, The operation unit includes: A main body case that is held by a surgeon; an operation receiving portion to which a base end of the operation wire is fixed and which is pivotally supported relative to the main body case so as to be swingable; having The towing operation is an operation of swinging the operation receiving unit, The operation unit further has a holding mechanism for holding the distal end portion in a bent state, The catheter according to any one of (1) to (5), wherein the holding mechanism is a mechanism for holding the operation receiving part at one of a plurality of preset swing angles, or a mechanism for holding the operation receiving part at a stepless swing angle. (7) The holding mechanism includes a concave-convex structure portion including a plurality of concaves and convexes, and a fitting portion that fits into a concave-convex portion corresponding to a pivot angle of the operation receiver, among the plurality of concaves and convexes of the concave-convex structure portion; Either the concave-convex structure portion or the fitting portion is formed on the operation receiving portion, The catheter according to (6), wherein the engagement portion is engaged with any one of the projections and recesses of the uneven structure portion, thereby holding the operation receiving portion at any one of the multiple swing angles. (8) The operation receiving portion has a sector portion formed in a sector shape and is supported pivotally so as to be swingable in a circumferential direction of the sector portion, The catheter according to (7), wherein the plurality of projections and recesses are arranged in a line in the circumferential direction of the arcuate peripheral surface of the sector portion. (9) The uneven structure portion is formed on the operation receiving portion, The catheter according to (7) or (8), wherein the holding mechanism has an abutment member including the fitting portion, and a biasing portion that biases the abutment member so that the fitting portion is pressed against the operation receiving portion. [Explanation of symbols]

[0120] 10 Tubular body 10a Distal end 11 Marker 12. Adhesive 13 Hole 13a 1st hole 13b 2nd hole 14 Flexible section 15 Connecting part 17 Lock operation section 18 Notch shape 18a Straight section 18b Intersection 20 lumens 21 First Lumen 22 Second Lumen 23 The Third Lumen 23a Balloon hole 24 The Fourth Lumen 30 Branch 31 Branch pipe for liquid supply 31a Liquid delivery connector 32 Balloon branch tube 32a Balloon connector 33 Pressure monitor branch pipe 33a Pressure monitor connector 33b Pressure monitor cap 34 Opening and closing members 35 Cover material 40 Reinforcement tube 40a Distal end 50 Operating Line 50a Tip 50b Proximal end 51 Hook 60 Balloon 61 Distal end 62 Proximal end 63 Middle Section 65 Sleeve 70 Operation section 71 Wheel operation unit 72 Main unit case 72a First body member 721c 2nd shaft member 72b Second body member 73 Opening 74 Retention mechanism 75 Operation receiver 75a Sliding part 76 Uneven structure 76a Unevenness 77 Contact member 77a Protrusion 77b Tip side part 77c proximal part 77d 2nd shaft hole 78 Fitting part 78a Tip surface 79a Tip corner 79 Pressurizing part 80 Sector 80a circumferential surface 81a Peripheral wall part 81b Plate-shaped part 81c 1st wall 81d Second wall 82 Protrusion 82a Tip 82b Proximal end 83a Slit section 84a, 84b Cylindrical part 85 First shaft hole 86 First shaft member 87 Second plate-shaped part 88 Third shaft member 89 Storage unit 89a First plate-shaped part 89b Second plate-shaped portion 91 Friction part 92 Pressure Welding Part 92a Tip surface 93 Sliding Part 95 Blank 100 Catheters 110 Introducer 112 Cylindrical body 113 2nd connection part 114 Side Port 114a tube 114b Three-way stopcock 116 Protrusion

Claims

1. A catheter for supplying cardioplegia to a coronary artery by being placed in the coronary sinus of a heart, A tubular body having a plurality of lumens; a hole for supplying the cardioplegia solution formed at a distal end of the tubular body and communicating with the first lumen; A reinforcing tube inserted into the second lumen; An operating wire inserted through the reinforcing tube; having the material constituting the reinforcing tube is a material having a bending rigidity greater than that of the material constituting the tubular body, the stiffening tube extends from the proximal end of the tubular body to the distal end, a tip end of the operating wire is led out from the distal end of the reinforcing tube and fixed to the distal end of the tubular body on the distal side of the distal end of the reinforcing tube, A catheter in which a portion of the tubular body distal to the distal end of the reinforcing tube is selectively bent when the operating wire is pulled.

2. A catheter as described in claim 1, wherein the reinforcing tube is made of a metal material.

3. a balloon disposed on an outer periphery of the distal end of the tubular body and in communication with the third lumen; the third lumen is for injecting a liquid into the balloon; the first lumen, the second lumen, and the third lumen are spaced apart from one another within a transverse cross-section of the tubular body; 3. The catheter according to claim 1, wherein the reinforcing tube extends from a proximal side of the tubular body to a region near the proximal side of the region in which the balloon is disposed.

4. The catheter according to claim 3 , wherein the distal end of the reinforcing tube is disposed proximally relative to the region in which the balloon is disposed.

5. The first lumen and the second lumen are spaced apart from each other within a cross section of the tubular body, The catheter according to claim 1 , wherein the first lumen is separated from the second lumen by a wall of the tubular body up to the distal end of the tubular body.

6. The inner diameter of the second lumen is smaller than the inner diameter of the first lumen, the second lumen extends distally beyond the distal end of the stiffening tube; The catheter according to claim 1 , wherein the operating wire is disposed within the second lumen extending distally beyond the distal end of the reinforcing tube.

7. 7. The catheter according to claim 1, wherein the hole portion comprises a first hole portion formed in the distal end of the tubular body and a second hole portion formed in the circumferential surface of the distal end portion of the tubular body.

8. The catheter is inserted into a vein through an introducer that is percutaneously inserted into the vein; a flexible sleeve that is inserted around the tubular body and is expandable and contractible in the axial direction; a cylindrical coupling portion that is circumferentially and fluid-tightly provided on the distal end portion of the sleeve and is axially slidable relative to the tubular body; Further comprising: The catheter of claim 1 , wherein the connecting portion is detachably connectable to the introducer.

9. The distal end of the tubular body is bent by a pulling operation of the operating wire. The operation unit includes: A main body case that is held by a surgeon; an operation receiving portion to which a base end of the operation wire is fixed and which is pivotally supported relative to the main body case so as to be swingable; having The towing operation is an operation of swinging the operation receiving unit, The operation unit further has a holding mechanism for holding the distal end portion in a bent state, The catheter according to any one of claims 1 to 8, wherein the holding mechanism is a mechanism for holding the operation receiving part at any one of a plurality of preset swing angles, or a mechanism for holding the operation receiving part at a stepless swing angle.

10. the holding mechanism has a concave-convex structure portion including a plurality of concaves and convexes, and a fitting portion that fits into a concave-convex portion corresponding to a pivot angle of the operation receiving portion among the plurality of concaves and convexes of the concave-convex structure portion, Either the concave-convex structure portion or the fitting portion is formed on the operation receiving portion, The catheter according to claim 9, wherein the engagement portion is engaged with any of the projections and recesses of the uneven structure portion, thereby holding the operation receiver at any of the multiple swing angles.

11. The operation receiving portion has a sector portion formed in a sector shape, and is supported pivotally so as to be swingable in a circumferential direction of the sector portion, The catheter according to claim 10, wherein the plurality of projections and recesses are arranged in a circumferential direction of the arcuate peripheral surface of the sector portion.

12. The concave-convex structure is formed on the operation receiving portion, The catheter according to claim 10 or 11, wherein the holding mechanism comprises: a contact member including the fitting portion; and a biasing portion that biases the contact member so that the fitting portion is pressed against the operation receiving portion.

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