WO2018181312A1

WO2018181312A1 - Balloon catheter and method for manufacturing medical elongated body

Info

Publication number: WO2018181312A1
Application number: PCT/JP2018/012433
Authority: WO
Inventors: 明彦垂永; 啓二福田
Original assignee: テルモ株式会社
Priority date: 2017-03-28
Filing date: 2018-03-27
Publication date: 2018-10-04
Also published as: JPWO2018181312A1; JP6982061B2

Abstract

[PROBLEM] To provide a balloon catheter capable of preventing fracture of an inner shaft in the vicinity of a base end opening portion of the balloon catheter, and to provide a method for manufacturing a medical elongated body. [SOLUTION] A balloon catheter 10 is provided with an inner shaft 140, a base end of which has a base end opening portion 105 that opens on the outer surface of an outer base end shaft 130, and the inner shaft 140 has a convex portion 150 on a portion of a circumferential portion 105a forming the base end opening portion 105.

Description

Balloon catheter and method for producing medical elongated body

The present invention relates to a balloon catheter and a method for producing a medical elongated body.

A balloon catheter is widely known as a medical device for dilating a lesion such as a stenosis formed in a body lumen such as a blood vessel. Balloon catheters generally include what is called an over-the-wire type and what is called a rapid exchange type.

As described in Patent Document 1 described below, a rapid exchange type balloon catheter has a guide wire lumen through which a guide wire is inserted only at the distal end side of the catheter shaft on which the balloon is disposed. For this reason, a guide wire port (proximal end opening) is provided at a predetermined position on the distal end side in the axial direction (longitudinal direction) of the catheter shaft so that the guide wire can be taken in and out of the guide wire lumen.

The catheter shaft used for the rapid exchange type balloon catheter is formed by integrating the outer distal shaft, the outer proximal shaft, and the inner shaft constituting the catheter shaft with each other in the vicinity of the guide wire port. The outer distal shaft and the outer proximal shaft are tubular members that form an expansion lumen through which a pressurized medium (working fluid) for balloon expansion flows. The inner shaft is a tubular member with a lumen that forms a guidewire lumen.

JP2015-93173A

An operator such as a doctor inserts a guide wire into a lesion such as a stenosis formed in a blood vessel in a procedure using a balloon catheter. The surgeon inserts the proximal end side of the guide wire into the guide wire lumen from the distal end side of the inner shaft, and guides the guide wire from the guide wire lumen through the guide wire port on the proximal end side of the inner shaft. Then, the surgeon guides the balloon of the balloon catheter to the lesion by moving the balloon catheter along the guide wire.

During the procedure, the operator moves the guide wire to the proximal side or the distal side with the guide wire inserted through the guide wire lumen of the balloon catheter, or removes the guide wire from the proximal end opening of the inner shaft. To do. When the surgeon performs these operations, if an excessive stress concentration occurs near the guide wire port of the inner shaft, the inner shaft of the balloon catheter may break. When the guide wire is sandwiched between the broken portions (the torn portions) of the inner shaft, it becomes difficult for the operator to move the guide wire smoothly, so that the operability of the guide wire is significantly reduced.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a balloon catheter capable of preventing the inner shaft from breaking near the proximal end opening of the balloon catheter, and a method for manufacturing a medical elongated body. And

A balloon catheter according to the present invention includes an outer distal shaft, and an outer proximal shaft fixed to the proximal end side of the outer distal shaft and having a lumen communicating with the lumen of the outer distal shaft. A shaft, an inner shaft in which a distal end side is disposed in a lumen of the outer distal shaft and a proximal end side is disposed on an outer surface of the outer proximal shaft, and a balloon fixed to the inner shaft and the outer distal shaft And a proximal end of the inner shaft has a proximal end opening that opens at an outer surface of the outer proximal shaft, and the inner shaft is a part of a peripheral edge that forms the proximal end opening. Have protrusions.

In addition, the manufacturing method of the medical elongated body according to the present invention includes an outer distal shaft, an outer proximal shaft, an inner shaft, a first mandrel disposed in a lumen of the inner shaft, and the outer distal shaft. A second mandrel disposed in a lumen and a lumen of the outer proximal shaft, wherein the first mandrel overlaps the first region and the proximal side of the first region in the axial direction, A second region extending proximally from the proximal end of the first region, a recess is formed between the first region and the second region, and the outer distal shaft The inner shaft is disposed in a lumen, and the first region of the first mandrel is inserted into the lumen of the inner shaft so that the proximal end of the inner shaft is axially aligned with the recess of the first mandrel. The first mandrel to overlap And arranging the outer proximal shaft such that the lumen of the outer distal shaft and the lumen of the outer proximal shaft are continuous with the inner shaft along the outer surface of the outer proximal shaft, The second mandrel is inserted into the outer distal shaft lumen and the outer proximal shaft lumen to cover the outer distal shaft, the outer proximal shaft, the inner shaft, and the second region of the first mandrel. The heat shrinkable tube is arranged in such a manner that heat is applied to the heat shrinkable tube to cause shrinkage, and the outer distal shaft, the outer proximal shaft, and the inner shaft are fused and disposed in the recess of the first mandrel. Forming a convex portion at the proximal end of the inner shaft.

The balloon catheter configured as described above has a convex portion formed at a part of the peripheral edge forming the proximal end opening of the inner shaft. The convex portion of the inner shaft can prevent the inner shaft from breaking even when excessive stress concentration occurs in the vicinity of the proximal end opening when the guide wire is taken out from the proximal end opening of the inner shaft. For this reason, the balloon catheter can prevent the inner shaft from being broken, and can prevent the operability of the guide wire from being lowered as the inner shaft is broken.

In the manufacturing method of the above-described medical elongated body, when the inner shaft and the outer shaft are fused, the first region included in the first mandrel is inserted into the inner shaft lumen, and the first region of the first mandrel is inserted. The base end of the inner shaft is disposed in a recess formed between the first mandrel and the second region of the first mandrel, and covers the outer tip shaft, the outer base shaft, the inner shaft, and the second region of the first mandrel. Place the heat shrink tube so that. And the said manufacturing method gives heat to a heat contraction tube, and is made to shrink | contract, while fuse | melting an outer front end shaft, an outer base end shaft, and an inner shaft, the inner shaft arrange | positioned in the recessed part of a 1st mandrel. A convex part is formed at the base end. Thereby, the said manufacturing method can provide a medical elongate body provided with the inner side shaft in which the convex part which prevents that a fracture | rupture arises in an inner side shaft near a base end opening part was formed.

It is a figure which shows the balloon catheter which concerns on embodiment. 2A is an enlarged cross-sectional view of a portion surrounded by a broken line portion 2A in FIG. 1, and FIG. 2B is an enlarged cross-sectional view of a portion surrounded by the broken line portion 2B in FIG. It is a figure which expands and shows the part enclosed with the broken-line part 3A in FIG. 2 (B). FIG. 4 is a view for explaining the method for manufacturing the medical elongated body according to the embodiment, and FIG. 4A is a cross-sectional view showing a state in which the inner shaft is disposed so as to overlap the outer tip shaft in the axial direction. 4B is a cross-sectional view showing a state where the first mandrel is inserted into the inner shaft, and FIG. 4C is a cross-sectional view showing a state where the outer proximal shaft is inserted into the lumen of the outer distal shaft. It is. FIG. 5 is a view for explaining the method for manufacturing the medical elongated body according to the embodiment, and FIG. 5 (A) shows the second mandrel in the lumen of the outer distal shaft and the lumen of the outer proximal shaft. FIG. 5B is a cross-sectional view showing a state in which a heat-shrinkable tube is arranged. FIG. 6 is a diagram for explaining a method for manufacturing a medical elongated body according to the embodiment, and FIG. 6A is an enlarged cross-sectional view illustrating a state where a convex portion is formed on the inner shaft. FIG. 6B is an enlarged cross-sectional view illustrating a state after the convex portion is formed on the inner shaft. It is sectional drawing for demonstrating the positional relationship of the large diameter part formed in a heat contraction tube and an outer front end shaft. It is an expanded sectional view showing the convex part of the inner side shaft concerning a modification. It is an expanded sectional view showing the convex part of the inner side shaft concerning a modification. It is an expanded sectional view which shows the convex part of the inner side shaft which concerns on another modification.

As shown in FIG. 1, the balloon catheter 10 according to the present embodiment expands a balloon 160 disposed on the distal end side of the shaft 100 at a lesion such as a stenosis formed in a living body lumen, thereby causing a lesion. Is a medical device that spreads and treats.

The balloon catheter 10 is configured as a PTCA treatment balloon catheter used to widen the stenosis of the coronary artery. However, the balloon catheter 10 is used to treat lesions such as stenosis formed in other blood vessels, bile ducts, trachea, esophagus, other gastrointestinal tract, urethra, ear nasal lumen, and other living organs. It can also be configured as the intended balloon catheter.

Hereinafter, the balloon catheter 10 will be described.

As shown in FIG. 1, a balloon catheter 10 includes a long shaft (corresponding to a “medical long body”) 100, a balloon 160 disposed on the distal end side of the shaft 100, and a proximal end of the shaft 100. And a hub 190 disposed on the side.

In the description of the embodiment, the side on which the balloon 160 is disposed is the distal end side of the balloon catheter 10, the side on which the hub 190 is disposed is the proximal end side of the balloon catheter 10, and the direction in which the shaft 100 extends is the axial direction. Further, in the description of the embodiments, the distal end portion means a certain range including the distal end (the most distal end) and the periphery thereof, and the proximal end portion means a certain range including the proximal end (the most proximal end) and the periphery thereof. Means range.

As shown in FIG. 1, the balloon catheter 10 is configured as a so-called rapid exchange type catheter in which a proximal end opening (guide wire port) 105 through which a guide wire 200 can enter and exit is formed near the distal end side of the shaft 100. ing.

As shown in FIGS. 2A and 2B, the shaft 100 is disposed in the outer shaft 110 including the inner lumen (expansion lumen) 115, the inner lumen 115 of the outer shaft 110, and the guide wire 200. And an inner shaft 140 provided with a lumen (guide wire lumen) 145 through which is inserted.

As shown in FIGS. 1 and 2B, the shaft 100 has a proximal end opening (corresponding to a “proximal opening of the inner shaft”) 105 that communicates with the lumen 145 of the inner shaft 140. Yes. The proximal end opening 105 is formed near the proximal end of the inner shaft 140.

As shown in FIG. 2B, the outer shaft 110 has an outer distal shaft 120 and an outer proximal shaft 130 fixed to the proximal end side of the outer distal shaft 120.

The outer front end shaft 120 is formed of a tubular member in which a lumen 125 extending in the axial direction is formed. Similarly, the outer proximal shaft 130 is formed of a tubular member in which a lumen 135 extending in the axial direction is formed.

The outer distal shaft 120 and the outer proximal shaft 130 are integrally connected (fused) with the inner shaft 140 in the vicinity of the proximal opening 105 of the shaft 100.

The lumen 125 of the outer distal shaft 120 and the lumen 135 of the outer proximal shaft 130 communicate with each other. In addition, the lumen 125 of the outer distal shaft 120 and the lumen 135 of the outer proximal shaft 130 are in communication with each other to form a lumen (expansion lumen) 115 that communicates with the expansion space 167 of the balloon 160.

The outer distal shaft 120 and the outer proximal shaft 130 are, for example, polyolefins such as polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, thermoplastic resins such as soft polyvinyl chloride, polyurethane elastomer, polyamide It can be formed of various elastomers such as elastomer and polyester elastomer, and crystalline plastics such as polyamide, crystalline polyethylene, and crystalline polypropylene.

2A, the distal end side of the inner shaft 140 is disposed in the lumen 125 of the outer distal shaft 120. As shown in FIG. A certain range on the distal end side of the inner shaft 140 is arranged so as to protrude toward the distal end side of the outer distal shaft 120. Further, as shown in FIG. 2B, the inner shaft 140 has the proximal end side of the inner shaft 140 disposed on the outer surface of the outer proximal shaft 130.

As shown in FIG. 2 (A), the inner shaft 140 has a tip member 180 disposed on the tip side. The tip member 180 has a lumen 181 through which the guide wire 200 can be inserted.

The inner shaft 140 is provided with the tip member 180 on the tip side, so that it is possible to prevent the living organ from being damaged when the tip of the balloon catheter 10 contacts the living body lumen (such as the inner wall of the blood vessel). The tip member 180 can be formed of, for example, a flexible resin material. However, the material of the tip member 180 is not particularly limited as long as it can be fixed to the inner shaft 140.

2A, the lumen 145 of the inner shaft 140 communicates with the lumen 181 of the tip member 180 on the tip side of the inner shaft 140. As shown in FIG. Further, as shown in FIG. 2B, the inner lumen 145 of the inner shaft 140 communicates with the proximal end opening 105 on the proximal end side of the inner shaft 140. A convex portion 150 described later is formed in the vicinity of the proximal end opening portion 105 of the inner shaft 140.

The inner shaft 140 can be formed of the same material as exemplified as the constituent material of the outer shaft 110, for example.

As shown in FIG. 2A, the balloon 160 is fixed to a tip 161 fixed to the tip 141 of the inner shaft 140 and a tip 111 of the outer shaft 110 (corresponding to “tip of the outer tip shaft”). A proximal end portion 163 and an intermediate portion 166 forming a maximum outer diameter portion formed between the distal end portion 161 of the balloon 160 and the proximal end portion 163 of the balloon 160. Further, the balloon 160 includes a distal end side tapered portion 164 formed between the distal end portion 161 of the balloon 160 and the intermediate portion 166 of the balloon 160, and a gap between the proximal end portion 163 of the balloon 160 and the intermediate portion 166 of the balloon 160. And a proximal end side taper portion 165 formed in the above.

The balloon 160 forms an expansion space 167 communicating with the lumen 115 of the outer shaft 110 between the outer peripheral surface of the shaft 100. When the fluid flows into the expansion space 167, the balloon 160 expands in a radial direction that intersects the axial direction of the balloon 160.

The balloon 160 is made of, for example, polyethylene, polypropylene, polyolefin of ethylene-propylene copolymer, polyester such as polyethylene terephthalate, polyvinyl chloride, ethylene-vinyl acetate copolymer, cross-linked ethylene-vinyl acetate copolymer, polyurethane, etc. It can be formed of thermoplastic resin, polyamide, polyamide elastomer, polystyrene elastomer, silicone rubber, latex rubber or the like.

As shown in FIG. 2 (A), the inner shaft 140 has a contrast marker 170 indicating the approximate center position of the intermediate portion 166 of the balloon 160 in the axial direction. The contrast marker 170 can be formed of, for example, a metal such as platinum, gold, silver, iridium, titanium, tungsten, or an alloy thereof. Note that the contrast marker 170 is located at the position indicating the boundary between the distal tapered portion 164 and the intermediate portion 166 on the inner shaft 140 and between the proximal tapered portion 165 and the intermediate portion 166 on the inner shaft 140. You may arrange | position in the position which shows a boundary part.

As shown in FIG. 1, the hub 190 has a port 191 that can be connected in a liquid-tight and air-tight manner to a supply device (not shown) such as an indeflator for supplying a fluid (for example, a contrast medium or physiological saline). is doing. The port 191 of the hub 190 can be configured by, for example, a known luer taper configured such that a tube or the like can be connected / separated.

Next, the inner shaft 140 will be described in detail.

As shown in FIG. 2B, a proximal end opening (guide wire port) 105 that opens on the outer surface of the outer proximal shaft 130 is formed on the proximal end side of the inner shaft 140.

Further, as shown in FIG. 3, the inner shaft 140 has a convex portion 150 on a part of the peripheral edge part 105 a (part along the circumferential direction of the peripheral edge part 105 a) forming the proximal end opening 105. Note that the convex portion 150 is formed from the proximal end side to the distal end side of the inner shaft 140 in order to ensure flexibility while preventing breakage of the peripheral edge portion 105a forming the proximal end opening portion 105, as shown in FIG. It is preferably formed by increasing the wall thickness. FIG. 3 is an enlarged cross-sectional view (enlarged cross-sectional view of the inner shaft 140 in the axial direction) of the 3A portion surrounded by a broken line shown in FIG.

The above-mentioned “having a convex portion whose thickness increases from the proximal end side to the distal end side of the inner shaft” means at least the circumferential direction of the peripheral edge portion 105 a that forms the proximal end opening 105 of the inner shaft 140. In part, the thickness of the portion of the inner shaft 140 fused to the proximal end 123 of the outer distal shaft 120 or the vicinity of the distal end of the portion where the inner shaft 140 and the proximal end 123 of the outer distal shaft 120 are fused or It means that a portion having a thickness larger than the thickness of the non-fused portion located in the vicinity of the base end side is formed. For example, as shown in FIG. 3, the convex portion 150 may have a cross-sectional shape in which the thickness continuously increases from the proximal end side to the distal end side of the inner shaft 140, or a later-described modification example As shown in FIG. 10 (see FIG. 10), it may be a cross-sectional shape in which the thickness increases stepwise (a shape in which the thickness increases to a certain size with an arbitrary portion in the axial direction as a boundary).

As shown in FIG. 3, the convex portion 150 is connected to the first inclined portion 151 inclined from the proximal end side to the distal end side of the inner shaft 140 and the distal end of the first inclined portion 151 in the cross section of the inner shaft 140. And a second inclined portion 152 that is inclined from the distal end of the first inclined portion 151 toward the distal end side of the inner shaft 140.

In the cross section shown in FIG. 3, the first inclined portion 151 is inclined radially outward (in a direction away from the axis of the inner shaft 140) from the peripheral edge portion 105 a of the inner shaft 140 toward the proximal end side of the inner shaft 140. ing. The first inclined portion 151 extends substantially parallel to the opening surface of the proximal end opening 105. That is, the 1st inclination part 151 and the base end opening part 105 exist on the same plane.

In the cross section shown in FIG. 3, the second inclined portion 152 extends from the distal end of the first inclined portion 151 to the distal end side of the inner shaft 140 so as to exhibit a cross-sectional shape different from that of the first inclined portion 151. Specifically, the proximal end side of the second inclined portion 152 is curved so as to draw an arc toward the distal end side of the inner shaft 140. The distal end side of the second inclined portion 152 has a cross-sectional shape that draws an arc from the proximal end side of the first inclined portion 151 toward the outer surface side of the inner shaft 140 so as to be connected to the outer surface of the inner shaft 140. .

In addition, since the 1st inclination part 151 and the 2nd inclination part 152 are integrally formed as a part of the inner side shaft 140, they are not divided clearly on drawing, but the boundary of both is shown in FIG. In the cross section, it exists in the boundary part of the convex part 150 which the direction (direction which leaves | separates from the axial center of the inner shaft 140) in which the 1st inclination part 151 inclines changes in a different direction (direction which goes to the axial center side of the inner shaft 140). .

As shown in FIG. 3, the axial length L1 of the first inclined portion 151 of the convex portion 150 is formed longer than the axial length L2 of the second inclined portion 152 of the convex portion 150. The length L1 in the axial direction of the first inclined portion 151 and the length L2 in the axial direction of the second inclined portion 152 are the length in the axial direction of the longest portion on the cross section shown in FIG. It is.

The axial length L1 of the first inclined portion 151 of the convex portion 150 can be formed, for example, to 0.2 mm to 1.0 mm, and the axial length L2 of the second inclined portion 152 of the convex portion 150 is, for example, , 0.1 mm to 0.8 mm.

The proximal end opening 105 of the inner shaft 140 is disposed closer to the proximal end than the proximal end 123 of the outer distal shaft 120. Further, the inner shaft 140 has a flexible portion 158 that is thinner than the convex portion 150 and is flexible between the base end 123 of the outer distal shaft 120 and the convex portion 150.

The flexible part 158 is formed so as to have a thinner wall thickness than the convex part 150 of the inner shaft 140. That is, the flexible portion 158 is located in the vicinity of the distal end of the inner shaft 140 where the inner shaft 140 and the proximal end 123 of the outer distal shaft 120 are fused, and the proximal opening 105 of the inner shaft 140 is formed. This is a portion having a smaller thickness than the convex portion 150 provided on at least a part of the peripheral edge portion 105a to be formed. In addition, the outer surface of the flexible portion 158 has a shape that is recessed inward of the inner shaft 140 relative to the convex portion 150 in the cross section shown in FIG. Specifically, the flexible portion 158 is located between the base end 123 of the outer front end shaft 120 and the convex portion 150, and from the position of the outer surface of the shaft 100 at the base end 123 of the outer front end shaft 120 and the convex portion 150. Is also in a recessed position. As will be described later, when the flexible portion 158 forms the convex portion 150 disposed on the proximal end side of the inner shaft 140 with respect to the flexible portion 158, the resin forming the inner shaft 140 forms the convex portion 150. It is formed by flowing in. For this reason, the thickness of the flexible part 158 is smaller than the convex part 150 and smaller than the part other than the part where the convex part 150 is formed on the inner shaft 140.

The convex portion 150 can be formed, for example, in the range of 0.1 mm to 1.0 mm from the peripheral edge portion 105 a forming the proximal end opening portion 105 to the distal end side in the axial direction of the inner shaft 140. The flexible portion 158 can be formed in the range of 0.5 mm to 3.0 mm from the proximal end 123 of the outer distal shaft to the proximal end side of the inner shaft 140, for example. In addition, the portion t1 having the largest thickness in the convex portion 150 can be formed to be 0.1 mm to 0.5 mm, for example. Further, the portion t2 having the smallest wall thickness in the flexible portion 158 can be formed to 0.02 mm to 0.2 mm, for example.

As shown in FIG. 3, the proximal end opening 105 of the inner shaft 140 is inclined from the proximal end side to the distal end side of the inner shaft 140 in the axial section of the inner shaft 140. In the present embodiment, the first inclined portion 151 of the convex portion 150 and the proximal end opening portion 105 are arranged substantially in parallel so as to overlap on the same plane, but the proximal end opening portion 105 is, for example, the convex portion 150. You may arrange | position in parallel with the 1st inclination part 151, and there is no restriction | limiting in particular in the angle etc. which incline.

As shown in FIG. 3, the peripheral edge portion 105 a of the base end opening 105 of the inner shaft 140 is formed with a curved surface in the axial section of the inner shaft 140. The cross-sectional shape of the peripheral edge portion 105a can be formed, for example, so as to be curved with a predetermined curvature from the peripheral edge portion 105a toward the proximal end opening 105 formed on the inside thereof, as shown in the figure.

The cross-sectional shape of the peripheral edge portion 105a is not limited to a curved shape, and may be, for example, a triangle or a rectangle.

As shown in FIG. 2, the outer front end shaft 120 has a large-diameter portion 126 formed with a predetermined outer diameter D1. Further, the outer diameter D2 formed by the outer shaft 110 and the inner shaft 140 at a portion corresponding to the convex portion 150 of the inner shaft 140 is smaller than the outer diameter D1 of the large diameter portion 126.

As will be described later, when the inner shaft 140 and the outer shaft 110 (the outer distal shaft 120 and the outer proximal shaft 130) are fused (see FIG. 5B), both the

shafts

110, 140 are heat-shrinkable tubes 400. A predetermined range (range indicated by arrow A1 in FIG. 7) is covered. When heat is applied to both

shafts

110 and 140 in this state, both

shafts

110 and 140 are contracted radially inward (in the direction toward the inside of the shaft 100) in the range covered with the heat-shrinkable tube 400. At this time, the outer diameter is maintained before and after the fusion of the

shafts

110 and 140 within a range not affected by heat. As shown in FIG. 2B, a portion where the outer diameter of the outer front end shaft 120 is maintained before and after the fusion forms a large diameter portion 126.

Note that the outer diameter of the portion where the outer diameter is reduced after the

shafts

110 and 140 are fused, that is, the portion covered with the heat-shrinkable tube 400 when the

shafts

110 and 140 are fused is larger than the outer diameter portion 126. A small small diameter portion 127 is formed. Further, between the large diameter portion 126 and the small diameter portion 127, a boundary portion 128 is formed in which the outer diameter gradually increases from the small diameter portion 127 toward the large diameter portion 126 due to the effect of heat applied to the heat shrinkable tube 400. The

When the shaft 100 is manufactured, the region (indicated by the arrow A1 in FIG. 7) where the heat-shrinkable tube 400 is disposed is the region where the heat-shrinkable tube 400 is the outer distal shaft 120, the outer proximal shaft 130, the inner shaft 140, and the There is no particular limitation as long as it covers the second region 312 of the one mandrel 310. The distal end of the heat-shrinkable tube 400 is disposed at a position away from the distal end of the proximal end opening 105 of the inner shaft 140 toward the distal end side, and the proximal end of the heat-shrinkable tube 400 is the base of the proximal end opening 105 of the inner shaft 140. It arrange | positions in the position away from the end to the base end side.

As shown in FIG. 3, the convex portion 150 of the inner shaft 140 has a width along the axial direction of the inner shaft 140. Note that “having a width along the axial direction” as used herein means a portion (indicated by a broken line arrow w in the figure) in which the convex portion 150 extends along the axial direction in the cross section shown in FIG. It has a region to be shown).

As shown in FIG. 3, the width of the convex portion 150 of the inner shaft 140 increases toward the outer shaft 110 (outer proximal shaft 130) side. That is, the outer peripheral shape of the convex portion 150 is formed in such a shape that the contact area (fused area) with the outer shaft 110 gradually increases in the width direction toward the proximal end side along the axial direction of the inner shaft 140. ing.

In the present embodiment, in the cross section shown in FIG. 3, the convex portion 150 has a shape that is inclined so as to widen toward the outer shaft 110 side toward the proximal end side of the inner shaft 140. However, the shape of the convex part 150 is not limited to such a shape. For example, the convex portion 150 has a shape that is inclined so that the width decreases toward the outer shaft 110 side toward the proximal end side of the inner shaft 140, or a constant width toward the proximal end side of the inner shaft 140. You may form so that it may be formed.

Next, a method for manufacturing the shaft (long medical body) 100 will be described.

First, an operator who manufactures the shaft 100 supplies (preparation) the outer distal shaft 120, the outer proximal shaft 130, and the inner shaft 140.

The operator prepares, for example, a tubular member having an outer diameter and an inner diameter substantially constant in the axial direction as the outer tip shaft 120. In addition, the operator may use, for example, a tubular member whose outer base end shaft 130 is inclined obliquely from the front end side toward the base end side, and a portion other than the front end has a substantially constant outer diameter and inner diameter in the axial direction. Prepare. In addition, the operator may, for example, as the inner shaft 140, a tubular member having a base end inclined obliquely from the base end side toward the front end side, and a portion other than the base end having a substantially constant outer diameter and inner diameter in the axial direction. (Refer to FIG. 4C for examples of shapes of the

shafts

120, 130, and 140).

An operator may have a first mandrel 310 disposed in the lumen (guidewire lumen) 145 of the inner shaft 140, and a second mandrel disposed in the lumen 125 of the outer distal shaft 120 and the lumen 135 of the outer proximal shaft 130. 320 is supplied (prepared) (see FIG. 5A).

As shown in FIG. 4A, the first mandrel 310 includes a first region 311 disposed in the inner lumen 145 of the inner shaft 140 and a first end of the first region 311 while overlapping the proximal end side of the first region 311 in the axial direction. A second region 312 extending to the base end side of the base end of the region 311. A recess 313 is formed between the first region 311 of the first mandrel 310 and the second region 312 of the first mandrel 310.

The first region 311 of the first mandrel 310 extends substantially linearly in the axial direction. The second region 312 of the first mandrel 310 has a tip inclined toward the tip side, and forms a predetermined space with the first region 311. The concave portion 313 of the first mandrel 310 is formed so that the shape of the portion 313a facing the base end of the inner shaft 140 is the base end so that the peripheral edge portion 105a of the base end opening 105 of the inner shaft 140 can be formed in a curved cross-sectional shape. Curved concavely toward the side.

The worker arranges the inner shaft 140 in the inner cavity 125 of the outer tip shaft 120 as shown in FIG.

Next, the worker places the first mandrel 310 in the inner lumen 145 of the inner shaft 140 as shown in FIG. Specifically, the operator inserts the first mandrel 310 into the inner lumen 145 of the inner shaft 140 and the first mandrel 310 so that the proximal end of the inner shaft 140 overlaps the recess 313 of the first mandrel 310 in the axial direction. Place. At this time, the worker arranges the first mandrel 310 so that a part of the inner shaft 140 is exposed between the base end 123 of the outer distal shaft 120 and the recess 313 of the first mandrel 310.

Next, as shown in FIG. 4C, the operator places the inner shaft 140 along the outer surface of the outer proximal shaft 130, the lumen 125 of the outer distal shaft 120, and the inner proximal shaft 130. The outer proximal shaft 130 is arranged so that the cavities 135 are continuous.

Next, the operator inserts the second mandrel 320 into the inner cavity 125 of the outer distal shaft 120 and the inner cavity 135 of the outer proximal shaft 130 as shown in FIG. The second mandrel 320 may be a known one that extends substantially linearly in the axial direction.

The operator performs an operation of placing the inner shaft 140 in the inner cavity 125 of the outer distal shaft 120, an operation of arranging the first mandrel 310 on the inner shaft 140, and an operation of arranging the outer proximal shaft 130 on the outer distal shaft 120. The operation of inserting the second mandrel 320 into the lumen 125 of the outer distal shaft 120 and the lumen 135 of the outer proximal shaft 130 can be performed in any order.

Next, as shown in FIG. 5C, the worker covers the outer distal shaft 120, the outer proximal shaft 130, the inner shaft 140, and the second region 312 of the first mandrel 310 so as to cover the heat contraction tube 400. Place. As the heat-shrinkable tube 400, for example, a hollow cylindrical member made of polyolefin or the like can be used.

The worker applies heat to the heat-shrinkable tube 400 in a state where the heat-shrinkable tube 400 is arranged, and fuses the outer distal shaft 120, the outer proximal shaft 130, and the inner shaft 140. The heat-shrinkable tube 400 contracts when heated, and deforms such that the inner diameter of the heat-shrinkable tube 400 after heating is smaller than the inner diameter of the heat-shrinkable tube 400 before heating.

At this time, as shown in FIG. 6A, the inner shaft 140 is melted at a portion exposed from the concave portion 313 of the first mandrel 310 of the inner shaft 140, and the resin constituting the inner shaft 140 is made of resin of the first mandrel 310. The resin flows into the concave portion 313 side (in FIG. 6A, the resin flowing into the concave portion 313 side is indicated by a symbol f).

As shown in FIG. 6B, the resin constituting the inner shaft 140 that has flowed into the concave portion 313 side of the first mandrel 310 has increased in thickness from the proximal end side to the distal end side of the inner shaft 140. The convex part 150 is formed. At this time, the operator has exposed the portion where the thickness of the inner shaft 140 is reduced (exposed from the recess 313) due to the resin flowing into the recess 313 side between the base end 123 of the outer tip shaft 120 and the tip of the projection 150. The flexible part 158 is formed in the part).

As shown in FIG. 7, a small diameter portion 127 is formed in a portion (range indicated by arrow A <b> 1 in FIG. 7) covered with the heat shrink tube 400 in each

shaft

120, 130, 140. A boundary portion 128 is formed on the uncovered portion (the tip side from the small diameter portion 127), and a large diameter portion 126 is formed on the tip side of the boundary portion 128.

The operator performs the above-described steps to obtain the inner shaft 140 formed with the convex portion 150 and the flexible portion 158, and the outer shaft 110 constituted by the outer distal shaft 120 and the outer proximal shaft 130. The provided shaft 100 can be manufactured.

Next, the operation of the balloon catheter 10 according to this embodiment and the operation of the method for manufacturing the shaft 100 will be described.

The balloon catheter 10 according to this embodiment includes an outer distal shaft 120 and an outer proximal shaft having a lumen 135 that is fixed to the proximal end side of the outer distal shaft 120 and communicates with the lumen 125 of the outer distal shaft 120. 130, an inner shaft 140 whose distal end side is disposed in the lumen 125 of the outer distal shaft 120 and whose proximal end is disposed on the outer surface of the outer proximal shaft 130, and the inner shaft 140. And a balloon 160 fixed to the outer distal shaft 120. The base end of the inner shaft 140 has a base end opening (guide wire port) 105 that opens on the outer surface of the outer base end shaft 130, and the inner shaft 140 has a peripheral edge that forms the base end opening 105. A part of 105a has a convex portion 150 whose thickness increases from the proximal end side toward the distal end side.

In the balloon catheter 10 configured as described above, a convex portion 150 is formed on a part of the peripheral edge portion 105a that forms the proximal end opening portion 105 of the inner shaft 140. The convex portion 150 of the inner shaft 140 breaks the inner shaft 140 even when excessive stress concentration occurs in the vicinity of the proximal end opening 105 when the guide wire 200 is taken out from the proximal end opening 105 of the inner shaft 140. Can be prevented. For this reason, the balloon catheter 10 can prevent the inner shaft 140 from being broken, and can prevent the operability of the guide wire 200 from being lowered as the inner shaft 140 is broken.

The proximal end opening 105 of the inner shaft 140 is disposed on the proximal end side with respect to the proximal end 123 of the outer distal shaft 120, and the inner shaft 140 is disposed between the proximal end 123 of the outer distal shaft 120 and the convex portion 150. Further, the flexible portion 158 is thinner than the convex portion 150 and is flexible.

The balloon catheter 10 configured as described above has a flexible portion 158 formed on the distal end side of the inner shaft 140 with respect to the convex portion 150. Therefore, when a stress acts on the convex portion 150 from the guide wire 200 when the guide wire 200 is operated, the inner shaft 140 is deformed (bent) so that the vicinity of the convex portion 150 is swollen starting from the flexible portion 158. Therefore, it is possible to prevent stress concentration from occurring near the proximal end opening 105 of the inner shaft 140. Thereby, the balloon catheter 10 can more preferably prevent the proximal end opening 105 of the inner shaft 140 from being broken. Further, since the balloon catheter 10 has a flexible portion 158 formed on the distal end side of the inner shaft 140 with respect to the convex portion 150, the flexible portion 158 is moved by the guide wire 200 along the guide wire 200 when the balloon catheter 10 is moved. Following 200 is easily curved, and the followability to guide wire 200 is enhanced.

Further, the proximal end opening 105 of the inner shaft 140 is inclined from the proximal end side toward the distal end side in the axial section of the inner shaft 140. For this reason, the opening area of the proximal end opening 105 can be formed larger than when the proximal end opening 105 of the inner shaft 140 is opened so as to be orthogonal to the axial direction of the inner shaft 140. Thereby, the operator can easily take out the guide wire 200 through the proximal end opening 105 of the balloon catheter 10.

The outer tip shaft 120 has a large-diameter portion 126 formed with a predetermined outer diameter, and the outer shaft 110 and the inner shaft 140 are formed at portions corresponding to the convex portions 150 formed on the inner shaft 140. The diameter is smaller than the outer diameter of the large diameter portion 126.

When an operator inserts the balloon catheter 10 into a living body lumen such as a blood vessel, for example, using one catheter (a known guiding catheter or the like), the balloon catheter 10 and another medical device (for example, a balloon catheter) are used. In some cases, another balloon catheter or a catheter device used for diagnostic imaging may be inserted. At this time, if the outer diameter of the shaft 100 at the convex portion 150 formed on the balloon catheter 10 is excessively large, the balloon catheter 10 and other medical devices interfere with each other in the catheter, and the smooth movement of both is hindered. Sometimes. The balloon catheter 10 is formed on the inner shaft 140 because the outer diameter of the convex portion 150 formed on the inner shaft 140 is smaller than the outer diameter of the large diameter portion 126 of the outer tip shaft 120 as described above. Regardless of the formation of the convex portion 150, it is possible to suitably prevent interference with other medical devices in the lumen of the catheter.

Further, the convex portion 150 of the inner shaft 140 has a width along the axial direction of the inner shaft 140, and the width of the convex portion 150 increases toward the outer shaft 110 side. As a result, the inner shaft 140 has a larger contact area (fusion area) where the convex portion 150 and the outer surface of the outer shaft 110 are in contact with each other on the proximal end side of the inner shaft 140. Fixing force can be increased.

In addition, the convex portion 150 formed on the inner shaft 140 includes a first inclined portion 151 that is inclined from the proximal end side toward the distal end side in the axial section of the inner shaft 140, and the distal end of the first inclined portion 151. And a second inclined portion 152 that is inclined from the distal end of the first inclined portion 151 toward the distal end side of the inner shaft 140. The length of the first inclined portion 151 in the axial direction is longer than the length of the second inclined portion 152 in the axial direction.

The balloon catheter 10 configured as described above has a relatively long axial length of the first inclined portion 151 formed on the proximal end side of the convex portion 150, so that the inner side in the axial direction of the inner shaft 140 is formed. The region where the outer diameter of the shaft 140 changes (the region from the base end of the convex portion 150 to the maximum outer diameter portion of the convex portion 150) becomes longer. That is, since the inner shaft 140 has a longer axial length in a region where the outer diameter of the convex portion 150 changes so as to increase, a sudden decrease in the outer diameter of the convex portion 150 can be suppressed. Accordingly, in the balloon catheter 10, the amount of increase in the outer diameter from the proximal end side to the distal end side of the convex portion 150 becomes gradual, so that a kink or the like of the inner shaft 140 caused by a sudden increase in the outer diameter occurs. Can be prevented.

Further, the peripheral edge portion 105a of the base end opening 105 of the inner shaft 140 is formed as a curved surface. For this reason, when the operator takes out the guide wire 200 from the proximal end opening 105 of the inner shaft 140, the guide wire 200 can be prevented from being caught by the peripheral edge 105a of the proximal end opening 105, and the guide wire 200 can be smoothly moved. It can be taken out.

The manufacturing method of the shaft 100 according to the present embodiment includes the outer distal shaft 120, the outer proximal shaft 130, the inner shaft 140, the first mandrel 310 disposed in the lumen 145 of the inner shaft 140, and the outer distal shaft 120. , And a second mandrel 320 disposed in the lumen 135 of the outer proximal shaft 130, and the first mandrel 310 has a first region 311, a proximal end side of the first region 311 and a shaft A second region 312 extending closer to the base end side than the base end of the first region 311 while overlapping in the direction, and a recess 313 is formed between the first region 311 and the second region 312. Yes. In the manufacturing method, the inner shaft 140 is disposed in the inner lumen 125 of the outer tip shaft 120, and the first region 311 of the first mandrel 310 is inserted into the inner lumen 145 of the inner shaft 140. The first mandrel 310 is disposed so that the proximal end thereof overlaps the concave portion 313 of the first mandrel 310 in the axial direction, and the inner shaft 140 is disposed along the outer surface of the outer proximal shaft 130, and the lumen 125 of the outer distal shaft 120 is disposed. And the outer proximal shaft 130 are arranged so that the inner lumen 135 of the outer proximal shaft 130 is continuous, and the second mandrel 320 is inserted into the inner lumen 125 of the outer distal shaft 120 and the inner lumen 135 of the outer proximal shaft 130. Outer distal shaft 120, outer proximal shaft 130, inner shaft 140, and first mandrel 31 The heat-shrinkable tube 400 is disposed so as to cover the second region 312, and heat is applied to the heat-shrinkable tube 400 to contract, and the outer distal shaft 120, the outer proximal shaft 130, and the inner shaft 140 are fused, A convex portion 150 is formed at the proximal end of the inner shaft 140 disposed in the concave portion 313 of the first mandrel 310.

In the manufacturing method of the shaft 100 described above, when the inner shaft 140 and the outer shaft 110 are fused, the first region 311 provided in the first mandrel 310 is inserted into the lumen 145 of the inner shaft 140 and the first mandrel 310 is inserted. The base end of the inner shaft 140 is disposed in a recess 313 formed between the first region 311 of the first mandrel 310 and the second region 312 of the first mandrel 310, and the outer distal shaft 120, the outer proximal shaft 130, and the inner shaft 140 and the heat shrink tube 400 are arranged to cover the second region 312 of the first mandrel 310. In the manufacturing method, heat is applied to the heat shrinkable tube 400 to cause the heat shrinkable tube 400 to shrink, thereby fusing the outer distal shaft 120, the outer proximal shaft 130, and the inner shaft 140 to the recess 313 of the first mandrel 310. A convex portion 150 is formed at the proximal end of the arranged inner shaft 140. Therefore, the manufacturing method can provide the shaft 100 including the inner shaft 140 in which the convex portion 150 that prevents the inner shaft 140 from breaking near the proximal end opening 105 is formed.

Further, in the method for manufacturing the shaft 100, the first mandrel 310 has the inner shaft 140 exposed so that the inner shaft 140 is exposed between the proximal end 123 of the outer distal shaft 120 and the distal end of the second region 312 of the first mandrel 310. Placed in. The portion of the inner shaft 140 exposed from the first mandrel 310 flows into the proximal end side of the inner shaft 140 so as to form a convex portion 150 when heat is applied to the heat shrinkable tube 400 and contracted. A flexible portion 158 having a thickness smaller than that of the convex portion 150 is formed.

The above manufacturing method of the shaft 100 can form the convex portion 150 on the inner shaft 140 and can form the flexible portion 158 on the distal end side of the inner shaft 140 with respect to the convex portion 150. The inner shaft 140 is deformed (bent) so that when the guide wire 200 is operated and stress is applied to the convex portion 150 from the guide wire 200, the vicinity of the convex portion 150 is swollen starting from the flexible portion 158. Further, stress concentration is prevented from occurring near the proximal end opening 105 of the inner shaft 140. Further, when the balloon catheter 10 is moved along the guide wire 200, the flexible portion 158 easily curves following the guide wire 200, thereby improving the followability of the balloon catheter 10 with respect to the guide wire 200.

Further, in the method for manufacturing the shaft 100, the recess 313 of the first mandrel 310 is formed in a shape in which a portion 313a facing the base end of the inner shaft 140 is curved. The proximal end of the inner shaft 140 is formed in a curved shape by the recess 313 of the first mandrel 310.

In the manufacturing method of the shaft 100 described above, the peripheral edge portion 105a of the proximal end opening 105 formed at the proximal end of the inner shaft 140 is formed in a curved sectional shape (curved sectional shape). Accordingly, when the operator takes out the guide wire 200 from the proximal end opening 105 of the inner shaft 140, the guide wire 200 can be prevented from being caught by the peripheral edge 105a of the proximal end opening 105, and the guide wire 200 can be smoothly moved. It can be taken out.

Next, a modification of the above-described embodiment will be described. Note that configurations, members, manufacturing processes, and the like that are not particularly mentioned in the modification can be the same as those in the above-described embodiment, and a description thereof is omitted.

<Modification>
FIG. 8 is a cross-sectional view showing a convex portion 550 of a balloon catheter according to a modification.

The balloon catheter according to Modification 1 is different from the balloon catheter 10 according to the embodiment described above in the cross-sectional shape of the convex portion 550 formed on the inner shaft 140.

As shown in FIG. 8, the convex portion 550 formed on the inner shaft 140 is a first inclination that is inclined from the proximal end side toward the distal end side in the axial cross section of the inner shaft 140 (the cross section shown in FIG. 7). Part 551 and a second inclined part 552 connected to the tip of the first inclined part 551.

The first inclined portion 551 extends substantially linearly at a predetermined inclination angle from the proximal end side to the distal end side of the inner shaft 140. The peripheral edge portion 105a of the base end opening 105 formed near the base end of the first inclined portion 551 is formed with a curved surface.

The second inclined portion 552 is inclined from the distal end of the first inclined portion 551 toward the distal end side of the inner shaft 140. The cross-sectional shape of the tip of the first inclined portion 551 is switched from the first inclined portion 551 extending in a substantially linear shape toward the curved second inclined portion 552 in the cross-sectional view shown in FIG. Present) at the boundary.

The second inclined portion 552 extends from the distal end of the first inclined portion 551 to the distal end side of the inner shaft 140 so as to exhibit a different cross-sectional shape from the first inclined portion 551 in the cross section shown in FIG. Specifically, the proximal end side of the second inclined portion 552 has a cross-sectional shape that draws an arc from the distal end of the first inclined portion 551 toward the distal end side. Further, the distal end side of the second inclined portion 552 has a cross-sectional shape that draws an arc from the proximal end side of the second inclined portion 552 toward the outer surface side of the inner shaft 140 so as to be connected to the outer surface of the inner shaft 140. ing.

As shown in FIG. 8, the axial length L1 of the first inclined portion 551 of the convex portion 550 is shorter than the axial length L2 of the second inclined portion 552 of the convex portion 550. The length L1 in the axial direction of the first inclined portion 551 and the length L2 in the axial direction of the second inclined portion 552 are the length in the axial direction of the longest portion on the cross section shown in FIG. It is.

The length L1 in the axial direction of the first inclined portion 551 of the convex portion 550 can be formed to be 0.1 mm to 0.8 mm, for example, and the length L2 in the axial direction of the second inclined portion 552 of the convex portion 550 is, for example, , 0.2 mm to 1.0 mm.

When forming the convex portion 550 according to the present modification, the operator prepares a mandrel having a concave portion having a cross-sectional shape corresponding to the cross-sectional shape of the convex portion 550 as the first mandrel. Similarly, when forming

convex portions

650 and 750 according to each modification described below, the operator prepares a first mandrel having a cross-sectional shape corresponding to the cross-sectional shape of each

convex portion

650 and 750.

As described above, the balloon catheter according to the present modification includes the first inclined portion in which the convex portion 550 formed on the inner shaft 140 is inclined from the proximal end side toward the distal end side in the axial section of the inner shaft 140. 551 and a second inclined portion 552 that is continuous with the distal end of the first inclined portion 551 and is inclined from the distal end of the first inclined portion 551 toward the distal end side of the inner shaft 140. The length of the first inclined portion 551 in the axial direction is shorter than the length of the second inclined portion 552 in the axial direction.

Even when the balloon catheter has the convex portion 550 having a cross-sectional shape as described in the present modified example formed on the inner shaft 140, when the guide wire 200 is taken out from the proximal end opening 105 of the inner shaft 140, etc. It is possible to prevent the inner shaft 140 from being broken near the proximal end opening 105, and to prevent the operability of the guide wire 200 from being lowered as the inner shaft 140 is broken.

In the balloon catheter according to the modification of FIG. 8, the axial length L1 of the first inclined portion 551 of the convex portion 550 and the axial length L2 of the second inclined portion 552 of the convex portion 550 are the same length. You may have. Even in this case, the balloon catheter can prevent the inner shaft 140 from breaking near the proximal end opening 105 when the guide wire 200 is taken out from the proximal end opening 105 of the inner shaft 140. It is possible to prevent the operability of the guide wire 200 from being lowered due to the breakage of the guide wire 200.

<Modification example>
As long as the thickness of the convex portion formed on the inner shaft 140 increases from the proximal end side to the distal end side of the inner shaft 140, the specific cross-sectional shape and the like are not particularly limited. For example, as shown in FIG. 9, the convex portion 650 has a cross-sectional shape in which the first inclined portion 651 is inclined obliquely toward the distal end side, and the second inclined portion 652 is extended substantially perpendicular to the direction orthogonal to the axial direction. You may have. Moreover, as shown in FIG. 10, the convex part 750 may have a substantially rectangular cross-sectional shape in which the first inclined part and the second inclined part are not formed. Further, as shown in FIGS. 9 and 10, the inner shaft 140 may not have the peripheral edge portion 105 a of the proximal end opening portion 105 formed in a curved surface (curved shape).

The balloon catheter has a cross-sectional shape as shown in FIGS. 9 and 10, and even when the

convex portions

650 and 750 are formed, when the guide wire 200 is taken out from the proximal end opening 105 of the inner shaft 140, It is possible to prevent the inner shaft 140 from being broken near the proximal end opening 105, and to prevent the operability of the guide wire 200 from being lowered as the inner shaft 140 is broken.

As mentioned above, although the manufacturing method of the balloon catheter which concerns on this invention, and a medical elongate body through embodiment etc. was demonstrated, this invention can be variously modified based on description of a claim, and each described embodiment It is not limited only to the contents.

For example, as long as the convex portion formed on the inner shaft is formed on a part of the peripheral edge portion forming the proximal end opening of the inner shaft, the range to be formed is not particularly limited.

Further, for example, the structure of the balloon catheter and the arrangement of the members described in the embodiments and the like can be changed as appropriate, and the use of the additional members described with reference to the drawings is omitted, or other additional operations that are not particularly described. The use of such a member can be performed as appropriate. Similarly, each step relating to the method for producing a medical long body and instruments used for production can be appropriately changed.

This application is based on Japanese Patent Application No. 2017-063765 filed on Mar. 28, 2017, the disclosure of which is incorporated by reference in its entirety.

10 balloon catheter,
100 shaft (medical long body),
105 proximal end opening (inner shaft proximal end opening),
105a peripheral edge,
110 outer shaft,
115 lumen of the outer shaft,
120 outer tip shaft,
123 proximal end of outer distal shaft,
125 lumen of the outer tip shaft,
126 Large diameter part,
127 Small diameter part,
128 border,
130 outer proximal shaft,
135 lumen of the outer proximal shaft,
140 inner shaft,
145 lumen of the inner shaft,
150, 550, 650, 750 convex portion,
151, 551 first inclined portion,
152, 552 second inclined portion,
158 flexible part,
160 balloon,
200 guide wire,
310 first mandrel,
311 first region,
312 second region,
313 recess,
313a a portion facing the proximal end of the inner shaft,
320 Second mandrel,
400 heat shrink tube.

Claims

An outer shaft comprising: an outer distal shaft; and an outer proximal shaft fixed to a proximal end side of the outer distal shaft and having a lumen communicating with the lumen of the outer distal shaft;
An inner shaft having a distal end disposed in the lumen of the outer distal shaft, and a proximal end disposed on an outer surface of the outer proximal shaft;
A balloon fixed to the inner shaft and the outer tip shaft;
The proximal end of the inner shaft has a proximal opening that opens at the outer surface of the outer proximal shaft;
The inner shaft has a convex portion at a part of a peripheral edge forming the proximal end opening.
The proximal end opening is disposed closer to the proximal side than the proximal end of the outer distal shaft,
The balloon catheter according to claim 1, wherein the inner shaft has a flexible portion that is thinner than the convex portion and is flexible between the proximal end of the outer distal shaft and the convex portion.
The balloon catheter according to claim 1 or 2, wherein the proximal end opening portion is inclined from the proximal end side toward the distal end side in an axial section of the inner shaft.
The outer tip shaft has a large diameter portion formed with a predetermined outer diameter,
The balloon catheter according to any one of claims 1 to 3, wherein an outer diameter formed by the outer shaft and the inner shaft at a portion corresponding to the convex portion is smaller than an outer diameter of the large diameter portion.
The convex portion has a width along the axial direction of the inner shaft,
The balloon catheter according to any one of claims 1 to 4, wherein a width of the convex portion increases toward the outer shaft side.
In the axial cross section of the inner shaft, the convex portion is connected to the first inclined portion inclined from the proximal end side toward the distal end side, and the distal end of the first inclined portion, and from the distal end of the first inclined portion. A second inclined portion that is inclined toward the tip side of the inner shaft,
The balloon catheter according to any one of claims 1 to 5, wherein an axial length of the first inclined portion is longer than an axial length of the second inclined portion.
The balloon catheter according to any one of claims 1 to 6, wherein a peripheral edge portion of the proximal end opening is formed with a curved surface.
An outer distal shaft, an outer proximal shaft, an inner shaft, a first mandrel disposed in the lumen of the inner shaft, a lumen disposed in the lumen of the outer distal shaft and a lumen of the outer proximal shaft; The first mandrel extends in the proximal direction from the proximal end of the first region while overlapping the first region and the proximal end side of the first region in the axial direction. A second region, and a recess is formed between the first region and the second region,
Placing the inner shaft in the lumen of the outer tip shaft;
By inserting the first region of the first mandrel into the lumen of the inner shaft, the first mandrel is arranged so that the proximal end of the inner shaft overlaps the recess of the first mandrel in the axial direction;
The outer proximal shaft is arranged so that the lumen of the outer distal shaft and the lumen of the outer proximal shaft are continuous with the inner shaft along the outer surface of the outer proximal shaft,
Inserting the second mandrel into the lumen of the outer distal shaft and the lumen of the outer proximal shaft;
A heat-shrinkable tube is disposed to cover the outer distal shaft, the outer proximal shaft, the inner shaft, and the second region of the first mandrel;
Heat is applied to the heat-shrinkable tube to cause the tube to shrink, and the outer distal shaft, the outer proximal shaft, and the inner shaft are fused to the proximal end of the inner shaft disposed in the recess of the first mandrel. The manufacturing method of the medical elongate body including forming a convex part.
The first mandrel is disposed on the inner shaft so as to expose the inner shaft between a proximal end of the outer distal shaft and a distal end of the second region of the first mandrel;
The portion exposed from the first mandrel in the inner shaft flows into the proximal end side of the inner shaft so as to form the convex portion when the heat shrinkable tube is contracted by applying heat to the convex portion. The manufacturing method of the medical elongate body of Claim 8 which forms the flexible part whose thickness is thinner than a part.
The concave portion of the first mandrel is formed in a shape in which a portion facing the proximal end of the inner shaft is curved,
The method for producing a medical elongated body according to claim 8 or 9, wherein a proximal end of the inner shaft is formed in a shape curved by the recess.