WO2023157533A1

WO2023157533A1 - Balloon catheter

Info

Publication number: WO2023157533A1
Application number: PCT/JP2023/001209
Authority: WO
Inventors: 千菜美高嶋; 豊夫馬
Original assignee: 株式会社カネカ
Priority date: 2022-02-18
Filing date: 2023-01-17
Publication date: 2023-08-24

Abstract

Provided is a balloon catheter that has improved torque transmission properties and enables a guide wire to slide preferably.　This balloon catheter comprises: a shaft (10) which has an inner cavity (100) that includes a second lumen (120) and a first lumen (110) through which a guide wire (50) is passed; a balloon which is disposed at a distal portion of the shaft (10); and a tube (20) which is provided to the second lumen (120). The first lumen (110) and the second lumen (120) are connected with each other in a cross-section perpendicular to the longitudinal axis. The outer wall of the tube (20) is in abutment with the wall of the second lumen (120). The first lumen (110) does not encompass the center (P1) of the shaft (10). The shaft (10) has restriction parts (40) that restrict the tube (20) so as not to move from the second lumen (120) to the first lumen (110).

Description

balloon catheter

The present invention relates to balloon catheters.

Diseases such as angina pectoris and myocardial infarction may be caused by the formation of a hardened narrowed part due to calcification etc. on the inner wall of the blood vessel. One of these treatment methods is angioplasty such as percutaneous transluminal coronary angioplasty (PTCA) and percutaneous transluminal angioplasty (PTA) in which a balloon catheter is used to dilate a stenosis. Angioplasty is a widely practiced minimally invasive therapy that does not require an open chest like bypass surgery.

A balloon catheter used for angioplasty generally has a structure in which a balloon that can be expanded or contracted by adjusting internal pressure is joined to the distal end of a shaft, and a guide wire is inserted through the shaft. and a lumen for supplying a fluid for regulating the internal pressure of the balloon. In angioplasty, a guidewire is first inserted into a blood vessel and advanced until the distal end of the guidewire is past the site to be treated. A balloon is inserted into the blood vessel along the guide wire, and when the balloon is delivered to the treatment target, the balloon is expanded by introducing a fluid, and the balloon expands the blood vessel. After treatment, the balloon is deflated and withdrawn from the body by removing fluid from the balloon. In a series of processes, since the balloon catheter is operated from the proximal side exposed to the outside of the body, it is necessary to efficiently transmit manipulations from the proximal side to the distal side of the balloon catheter.

For example, Patent Document 1 discloses a catheter support used in combination with a therapeutic catheter, which has a shaft portion shaped to restrict radial movement of the therapeutic catheter over a certain axial length. , attempts to suppress the bending of the therapeutic catheter and improve the pushability of the therapeutic catheter in the axial direction.

JP 2010-119776 A

In order to push the balloon catheter through the bends and stenosis of the blood vessel to the treatment target site, it is necessary not only to push the balloon catheter in the direction of movement, but also to rotate the balloon catheter around the central axis in some cases. . In such a case, not only the ability to efficiently transmit the operation on the proximal side to the distal side to push the catheter (pushability) and the ability to smoothly deliver the catheter along the guidewire (trackability), Torque transmissibility is required so that the rotational force applied on the side is transmitted to the distal side. In addition, a guide wire inserted longitudinally through the shaft of the balloon catheter must be able to slide well within the shaft. However, conventional balloon catheters have room for improvement in terms of torque transmissibility and slidability of the guidewire within the shaft.

In view of the above circumstances, an object of the present invention is to provide a balloon catheter that has improved torque transmissibility and allows a guide wire to slide smoothly.

One embodiment of the balloon catheter of the present invention that can solve the above problems is as follows.
[1] A balloon catheter having a longitudinal distal end and a proximal end, the shaft extending longitudinally and having a lumen, the lumen of the shaft a shaft including a second lumen extending longitudinally therethrough and a first lumen through which a guidewire is passed; a balloon disposed distally of the shaft; and a balloon disposed in the second lumen. the first lumen and the second lumen communicate with each other in a cross section perpendicular to the longitudinal direction, and the outer wall of the tube communicates with the wall of the second lumen In abutting cross-section perpendicular to the longitudinal direction, the first lumen does not include the centroid P1 of the outer edge of the shaft, and the shaft extends from the second lumen to the first lumen. A balloon catheter having a restraining portion that restrains it from moving outwards.

Since the shaft has a restricting portion that restricts movement of the tube from the second lumen to the first lumen, the tube disposed in the second lumen of the lumen of the shaft can be inserted into the first lumen through which the guidewire is inserted. Movement to the 1-lumen side is suppressed, and entanglement between the guidewire and the tube can be prevented. As a result, the slidability of the guide wire within the shaft can be improved. In addition, since the first lumen does not include the centroid P1 of the outer edge of the shaft in a cross section perpendicular to the longitudinal direction, the guide wire inserted through the first lumen can be arranged at the peripheral edge of the shaft. As a result, when the shaft is rotated about the central axis, the radial deflection of the shaft with respect to the guide wire can be increased, making it easier to adjust the path of the balloon catheter by rotating the shaft. As a result, it is possible to obtain a balloon catheter with improved torque transmissibility that allows even a curved blood vessel to be easily pushed while rotating the balloon catheter.

The balloon catheter according to the embodiment of the present invention preferably has the following [2] to [10].
[2] In a cross section perpendicular to the longitudinal axis direction, when a straight line connecting the centroid P1 and the centroid P2 of the outer edge of the tube is L1, and a straight line perpendicular to the straight line L1 is L2, the restricting portion is positioned between a first position where the maximum diameter of the first lumen is located and a second position where the maximum diameter of the second lumen is located in a direction parallel to the straight line L2. A balloon catheter according to [1], wherein the thickness is greater than the wall thickness at the second location.

[3] The balloon catheter according to [1] or [2], wherein the shaft and the tube are made of different materials.

[4] The balloon catheter according to any one of [1] to [3], wherein the stiffness of the tube is higher than the stiffness of the shaft.

[5] The balloon catheter according to any one of [1] to [3], wherein the stiffness of the tube is lower than the stiffness of the shaft.

[6] In a cross section perpendicular to the longitudinal axis direction, when a straight line connecting the centroid P1 and the centroid P2 of the outer edge of the tube is L1, and a straight line perpendicular to the straight line L1 is L2, the shaft is In a direction parallel to the straight line L2, a third position is provided at which the width of the lumen of the shaft is minimized by the restricting portion. When a line segment parallel to is L3, the outer edge of the tube is in contact with the line segment L3 or has a portion existing on the opposite side of the centroid P2 with respect to the line segment L3 [1] The balloon catheter according to any one of -[5].

[7] In a cross section perpendicular to the longitudinal axis direction, when a line connecting the centroid P1 and the centroid P2 of the outer edge of the tube is L1, and a straight line perpendicular to the straight line L1 is L2, the shaft is In a direction parallel to the straight line L2, a third position is provided at which the width of the lumen of the shaft is minimized by the restricting portion. When a line segment parallel to is L3, the outer edge of the tube does not have a portion on the opposite side of the centroid P2 with respect to the line segment L3. Any one of [1] to [5] Balloon catheter as described.

[8] The balloon catheter according to any one of [1] to [7], wherein a portion of the outer wall of the tube facing the first lumen is coated with a hydrophilic coating or a hydrophobic coating.

"9" The balloon catheter according to any one of [1] to [8], wherein the lumen wall of the shaft forming the first lumen is coated with a hydrophilic coating or a hydrophobic coating.

[10] The balloon catheter according to any one of [1] to [9], wherein the inner wall of the tube is coated with a hydrophilic coating or a hydrophobic coating.

According to the above balloon catheter, the slidability of the guidewire inserted through the first lumen of the shaft can be improved. As a result, the operations of delivering the guidewire to the treatment target site prior to the balloon, and delivering the balloon to the treatment target site along the guidewire after delivery of the guidewire can be performed quickly and safely. In addition, since the torque transmissibility of the balloon catheter can be improved, it becomes possible to easily insert the balloon catheter even in a crooked blood vessel by manipulation on the proximal side. As a result, balloon catheters can improve the safety and efficiency of procedures.

1 depicts a side view of a balloon catheter according to one embodiment of the present invention; FIG. In the III-III cross-sectional view of FIG. 1, a cross-sectional view with the tube removed is shown. 2 represents a cross-sectional view taken along line III-III of FIG. 1; Fig. 3 shows a cross-sectional view perpendicular to the longitudinal direction of a balloon catheter according to another embodiment of the invention; 5 illustrates another example of the cross-sectional view of FIG. 4; FIG.

Hereinafter, the present invention will be described based on the embodiments, but the present invention is not limited by the following embodiments, and can be implemented by making appropriate changes within the scope that can conform to the gist of the preceding and following descriptions. are also possible, and all of them are included in the technical scope of the present invention. In each drawing, for the sake of convenience, hatching, member symbols, etc. may be omitted, but in such cases, the specification and other drawings shall be referred to. In addition, the dimensions of various members in the drawings may differ from the actual dimensions, since priority is given to helping to understand the features of the present invention.

A balloon catheter according to an embodiment of the present invention will be described with reference to FIGS. 1 to 5. FIG. However, the invention is not limited to the embodiments shown in the drawings. FIG. 1 depicts a side view of a balloon catheter according to one embodiment of the invention. FIG. 2 shows a cross-sectional view of the III-III cross-sectional view of FIG. 1 with the tube removed. FIG. 3 is a cross-sectional view taken along line III-III of FIG. 1, showing a mode in which the shaft and the restricting portion are made of different members. 4 and 5 are cross-sectional views perpendicular to the longitudinal axis direction of a balloon catheter according to another embodiment of the present invention, showing different modes in which the restricting portion is formed by the thick wall portion of the shaft. there is 2 to 5 show cross-sectional views of a state in which the guidewire is inserted through the first lumen.

As shown in FIG. 1, the balloon catheter 1 according to the embodiment of the present invention has a distal end and a proximal end in the longitudinal direction x. The proximal end is the end on the proximal side in the longitudinal axis direction x, and the proximal side refers to the extending direction of the balloon catheter 1, that is, the direction toward the user's hand side in the longitudinal axis direction x. The distal end is the end on the distal side in the longitudinal direction x, and the distal side refers to the direction opposite to the proximal side, that is, the direction toward the treatment target. A direction connecting a centroid P1 of the outer edge of the shaft 10 and a point on the outer edge of the shaft 10 in a cross section perpendicular to the longitudinal direction x is defined as a radial direction y.

As shown in FIGS. 1-3, the balloon catheter 1 is a shaft 10 extending in the longitudinal direction x and having a lumen 100, the lumen 100 of the shaft 10 extending in the longitudinal direction x. and a first lumen 110 through which the guidewire 50 is inserted; a balloon 30 disposed distally of the shaft 10; and a tube 20 .

The tube 20 is preferably a flow path for fluid that is introduced when the balloon 30 is inflated and is discharged when it is deflated. Fluid can be introduced or expelled using an indeflator (balloon pressurizer) to control inflation and deflation of balloon 30 . The fluid may be a pressurized fluid pressurized by a pump or the like.

The balloon catheter 1 in which the balloon 30 is arranged at the distal portion of the shaft 10 has a configuration in which the distal portion of the tube 20 arranged in the second lumen 120 of the shaft 10 and the proximal end portion of the balloon 30 are connected. can do. The distal portion of the tube 20 and the proximal end portion of the balloon 30 are joined by bonding with an adhesive, welding, or a ring-shaped member at the place where the distal portion of the tube 20 and the proximal end portion of the balloon 30 overlap. It can be done by means such as attaching and crimping. Above all, it is preferable that the tube 20 and the balloon 30 are joined by welding. Since the tube 20 and the balloon 30 are welded together, even if the balloon 30 is repeatedly expanded or contracted, the joint with the tube 20 is unlikely to be released, and the joint strength between the tube 20 and the balloon 30 can be easily improved. .

As shown in FIG. 2, the first lumen 110 and the second lumen 120 communicate with each other in a cross section perpendicular to the longitudinal direction x. Although FIG. 2 shows a cross-sectional view with the tube 20 removed, the communication between the first lumen 110 and the second lumen 120 means that the tube 20 is removed as shown in FIG. It means that the first lumen 110 and the second lumen 120 are connected. By arranging the tube 20 in the second lumen 120 of the shaft 10, a configuration as shown in FIG. 3 can be obtained.

As shown in FIG. 3 , the outer wall of the tube 20 placed in the second lumen 120 abuts against the wall of the second lumen 120 . Preferably, the tube 20 is arranged in the second lumen 120 so that there is no gap between it and the wall of the second lumen 120 . In this case, no space is formed between the wall of the second lumen 120 and the outer wall of the tube 20, but preferably the tube 20 is not fixed to the second lumen 120, and the tube 20 is connected to the second lumen of the shaft 10. 120 is a separate member.

With the above configuration, the tube 20 disposed in the second lumen 120 is a separate member from the shaft 10, unlike the case where the shaft has a guide wire lumen and an inflation lumen as a fluid flow path that are not in communication with each other. Therefore, the material of the tube 20 can be selected according to the type of fluid and the desired catheter conditions. In addition, by forming the shaft 10 and the tube 20 from different materials, the shaft 10 and the tube 20 can be manufactured to have different rigidity, so that the operability of the balloon catheter 1 can be adjusted according to the purpose. becomes possible.

It is preferable that the shaft 10 does not have a boundary provided between the first lumen 110 and the second lumen 120 so that they are independent of each other. This allows communication between the first lumen 110 and the second lumen 120 . However, if the shaft 10 does not have a boundary between the first lumen 110 and the second lumen 120 for most of the longitudinal direction x, it may have a boundary for a portion of the longitudinal direction x. acceptable.

As shown in FIGS. 2 and 3, the shaft 10 does not have a boundary between the first lumen 110 and the second lumen 120, so the first lumen 110 and the second lumen 120 are not separate lumens. Therefore, it can be said that the first lumen 110 and the second lumen 120 are parts of the lumen 100 of the shaft 10 . That is, the first lumen 110 is the portion of the lumen 100 of the shaft 10 through which the guide wire 50 is inserted, and the second lumen 120 is the portion of the lumen 100 of the shaft 10 in which the tube 20 is arranged.

As shown in FIG. 3, the first lumen 110 does not include the centroid P1 of the outer edge of the shaft 10 in a cross section perpendicular to the longitudinal direction x. Since the first lumen 110 through which the guidewire 50 is inserted does not include the centroid P<b>1 of the outer edge of the shaft 10 , the guidewire 50 placed in the first lumen 110 can be placed at the periphery of the shaft 10 . As a result, when the shaft 10 is rotated around the central axis, the swing width of the shaft 10 in the radial direction y with respect to the guide wire 50 can be increased, and the path of the balloon catheter 1 can be easily adjusted by rotating the shaft 10. Become. As a result, the balloon catheter 1 with improved torque transmissibility can be easily pushed while rotating the balloon catheter 1 even in a curved blood vessel.

As shown in FIG. 3, the shaft 10 has a restriction portion 40 that restricts movement of the tube 20 from the second lumen 120 to the first lumen 110. The regulating portion 40 may be provided as a member separate from the shaft 10 as shown in FIG. 3, or may be provided because the wall thickness of the shaft 10 is thick as described later. In either case, when the straight line connecting the centroid P1 of the outer edge of the shaft 10 and the centroid P2 of the outer edge of the tube 20 is L1, and the straight line perpendicular to the straight line L1 is L2, It is preferable that the lumen 100 is narrowed in the direction parallel to the straight line L2 by the restricting portion 40 . With such a configuration, the tube 20 placed in the second lumen 120 can be restricted from moving from the second lumen 120 to the first lumen 110 by the restricting portion 40 . As a result, the guide wire 50 inserted through the first lumen 110 and the tube 20 can be prevented from becoming entangled, and the slidability of the guide wire 50 can be improved.

Here, in this specification, the lumen 100 of the shaft 10 refers to the space formed inside the restricting portion 40 of the shaft 10 when the tube 20 as shown in FIG. 2 is removed. When the restricting portion 40 is provided as a separate member from the shaft 10 , the restricting portion 40 is provided on the inner wall of the shaft 10 . This is a portion formed inside the restricting portion 40 rather than a portion defined by the inner wall of the regulating portion 40 . Further, when the tube 20 is arranged in the second lumen 120 as shown in FIG. 3, the second lumen 120 is occupied by the tube 20, but when the tube 20 is removed as shown in FIG. A space formed inside the portion 40 will be described as a lumen 100 of the shaft 10 .

The restricting portion 40 is preferably formed so that the cross-sectional shapes of the first lumen 110 and the second lumen 120 perpendicular to the longitudinal axis direction x each have a circular or oval shape. If the cross-sectional shape of the second lumen 120 is a shape that includes a part of a circular or oval shape, the outer shape of the tube 20 is also circular or oval shape, thereby facilitating manufacture of the balloon catheter 1 . In addition, if the cross-sectional shape of the first lumen 110 is a shape including a part of a circular or oval shape, it becomes easy to insert the guide wire 50 through the first lumen 110, and the outer shape of the guide wire 50 is also circular or oval. By doing so, it becomes easier to reduce the resistance between the guide wire 50 and the wall of the first lumen 110 and improve the slidability of the guide wire 50 .

FIG. 3 shows a mode in which the restricting portions 40 are provided on both sides in the radial direction y of the bore 100 of the shaft 10, but the restricting portions 40 may be provided only on one side in the radial direction y. . From the viewpoint of enhancing the effect of suppressing movement of the tube 20 arranged in the second lumen 120 to the first lumen 110 and facilitating the arrangement of the tube 20 having a circular outer cross-sectional shape, the restricting portion 40 are preferably provided on both sides in the radial direction y.

When the restricting portion 40 is provided as a separate member from the shaft 10 , it is preferable that the restricting portion 40 is fixed to the inner wall of the shaft 10 . Further, when the portion where the restricting portion 40 protrudes most inward in the radial direction y is defined as the most protruding portion 41, in the direction of the straight line L1, the first lumen 110 is located on one side of the most protruding portion 41 and the other side thereof. It is preferable that the restricting portion 40 is provided so that the second lumen 120 is formed at the end. That is, in the direction of the straight line L1, it is preferable that the first lumen 110 is formed on one side of a line segment L3 described later, and the second lumen 120 is formed on the other side of the line segment L3.

As shown in FIG. 3, in a cross section perpendicular to the longitudinal axis direction x, a straight line connecting the centroid P1 and the centroid P2 of the outer edge of the tube 20 is L1, and a straight line perpendicular to the straight line L1 is L2. Preferably, in the direction of L2, the width _W41 of the lumen 100 of the shaft 10 at the location where the highest protrusion 41 is located is less than the length _W20 defined by the outer edge of the tube 20. Such a configuration can prevent the tube 20 from moving from the second lumen 120 to the first lumen 110 .

As shown in FIG. 4, in a cross section perpendicular to the longitudinal direction x, a straight line connecting a centroid P1 of the outer edge of the shaft 10 and a centroid P2 of the outer edge of the tube 20 is L1, and a straight line perpendicular to the straight line L1 is L2. , the restricting portion 40 is positioned at a first position S1 where the maximum diameter of the first lumen 110 is located and a second position S2 where the maximum diameter of the second lumen 120 is located in the direction parallel to the straight line L2. between, the wall thickness of the shaft 10 may be thicker than the wall thickness at the second position S2. With such a configuration, the restricting portion 40 can be formed integrally with the shaft 10, and the manufacturing of the balloon catheter 1 can be facilitated.

FIG. 4 shows an example in which the restricting portion 40 is formed such that the cross-sectional shapes perpendicular to the longitudinal axis direction x of the first lumen 110 and the second lumen 120 are each substantially circular. The shape of 40 is not particularly limited as long as it satisfies the above requirements even if it is formed by increasing the wall thickness of shaft 10 .

FIG. 4 shows an example in which the wall thickness of the shaft 10 is thicker than the wall thickness at the second position S2 on both sides in the radial direction y, so that the restriction portion 40 is formed. On one side in the radial direction y, the wall thickness of the shaft 10 may be thicker than the wall thickness at the second position S2. From the viewpoint of enhancing the effect of suppressing movement of the tube 20 arranged in the second lumen 120 to the first lumen 110 and facilitating the arrangement of the tube 20 having a circular outer cross-sectional shape, the restricting portion 40 are preferably formed on both sides in the radial direction y.

It is preferable that the shaft 10 is made of a material having both flexibility and biocompatibility. resin, vinyl chloride resin, silicone resin, natural rubber, and the like. These may use only 1 type and may use 2 or more types together. Among others, the material constituting the shaft 10 is preferably at least one of polyamide resin, polyolefin resin, and fluorine resin. As a result, the slipperiness of the surface of the shaft 10 can be enhanced, and the insertability of the balloon catheter 1 within the body cavity can be improved.

When the restricting portion 40 is formed of a member separate from the shaft 10 , the material configuring the shaft 10 can be referred to as the material configuring the restricting portion 40 . From the viewpoint of facilitating fixation of shaft 10 and restricting portion 40 , it is preferable that the material configuring restricting portion 40 is the same as the material configuring shaft 10 . For fixing the shaft 10 and the restricting portion 40, means such as welding or adhesion can be used. When the restricting portion 40 is formed by increasing the wall thickness of the shaft 10, a mold having a shape capable of forming the first lumen 110 and the second lumen 120 when forming the shaft 10 should be used. Thus, the shaft 10 having the restricting portion 40 can be manufactured.

As shown in FIG. 1, the balloon 30 includes an expansion portion, a proximal sleeve portion located proximal to the expansion portion, and a distal sleeve portion located distal to the expansion portion. It is preferable to have a part. With such a configuration, at least a portion of the proximal sleeve portion can be configured to be connected to the tube 20, and the fluid introduced through the tube 20 can expand the expanded portion to perform vasodilation or the like. Action can be taken. Preferably, the proximal sleeve portion and the distal sleeve portion do not expand even in the expanded state of the expansion portion. Thereby, the connection between the balloon 30 and the tube 20 can be stabilized even when the balloon 30 is expanded. The expanded portion of the balloon 30 has a straight tube portion, a proximal tapered portion located proximal to the straight tube portion, and a distal tapered portion located distal to the straight tube portion. may be

Examples of materials for forming the balloon 30 include polyolefin resins such as polyethylene, polypropylene, and ethylene-propylene copolymer; polyester resins such as polyethylene terephthalate and polyester elastomer; polyurethane resins such as polyurethane and polyurethane elastomer; and polyphenylene sulfide. system resin; polyamide system resin such as polyamide and polyamide elastomer; fluorine system resin; silicone system resin; natural rubber such as latex rubber, and the like. These may use only 1 type and may use 2 or more types together. Among them, polyamide-based resins, polyester-based resins, and polyurethane-based resins are preferably used. In particular, it is preferable to use an elastomer resin from the viewpoint of thinning the balloon 30 and flexibility. Among polyamide-based resins, nylon 12, nylon 11, and the like are suitable as the resin constituting the balloon 30, and nylon 12 is more suitable because it can be formed relatively easily in blow molding.

The tube 20 is preferably a flow path for fluid that is introduced when the balloon 30 is inflated and is discharged when it is deflated. The cross-sectional shape of the tube 20 perpendicular to the longitudinal axis direction x is preferably circular, oval, or a shape including a portion thereof. Moreover, the cross-sectional shape of the tube 20 perpendicular to the longitudinal axis direction x is preferably a shape along the cross-sectional shape of the second lumen 120 perpendicular to the longitudinal axis direction x. This makes it easy to bring the outer wall of the tube 20 into contact with the wall of the second lumen 120 in a cross section perpendicular to the longitudinal direction x.

Materials constituting the tube 20 include resins such as polyimide resins, polyamide resins, PEEK resins, polyester resins, polyolefin resins, fluorine resins, vinyl chloride resins, polyurethane resins, and silicone resins. , nickel-titanium alloys, cobalt-chromium alloys, tungsten alloys, titanium, and stainless steel. Among others, the tube 20 is preferably made of metal. As long as the tube 20 is made of metal, the tube 20 allows the shaft 10 to move freely even though the shaft 10 does not have independent boundaries between the first lumen 110 and the second lumen 120 . It is possible to increase the rigidity. Thereby, the pushability of the balloon catheter 1 can be improved. In addition, if the tube 20 is made of metal, it is easy to impart a predetermined or higher rigidity to the shaft 10 even if the outer shape of the shaft 10 is reduced, so the trackability of the balloon catheter 1 can be improved. be.

In the balloon catheter 1, the shaft 10 and the tube 20 are preferably made of different materials. By forming the shaft 10 and the tube 20 from different materials, the shaft 10 and the tube 20 can be manufactured so as to have different rigidity. It is possible to adjust the operability according to the purpose.

The tube 20 may be made of different materials in the longitudinal direction x. For example, the central portion of tube 20 may be made of metal, and the distal and/or proximal ends of tube 20 may be made of resin. With this configuration, the central portion of the tube 20 in the longitudinal direction x is made of metal to increase the rigidity, while the ends of the tube 20 connected to the balloon 30 or the like are made of resin. 20 can be easily joined to the balloon 30 or the like.

The rigidity of the tube 20 is preferably higher than that of the shaft 10. By forming the shaft 10 from resin and forming the tube 20 from metal, or by forming the tube 20 from a resin that can impart higher rigidity than the resin forming the shaft 10, the rigidity of the tube 20 can be adjusted to the rigidity of the shaft 10. can be higher than Alternatively, even if the shaft 10 and the tube 20 are made of the same material, the rigidity of the tube 20 may differ from that of the shaft 10 due to structural differences such as making the wall thickness of the tube 20 thicker than that of the shaft 10 . can be made higher than Since the rigidity of the tube 20 is higher than that of the shaft 10, pushability and trackability of the balloon catheter 1 can be improved.

The rigidity of the tube 20 is preferably lower than that of the shaft 10. The rigidity of the tube 20 can be adjusted to the rigidity of the shaft 10 by forming the tube 20 from a resin having lower rigidity than the resin forming the shaft 10 or by making the wall thickness of the tube 20 thinner than the wall thickness of the shaft 10 . can be made lower than Since the rigidity of the tube 20 is lower than the rigidity of the shaft 10, the flexibility of the balloon catheter 1 can be improved and the trackability can be improved.

In a cross section perpendicular to the longitudinal axis direction x, when the straight line connecting the centroid P1 and the centroid P2 of the outer edge of the tube 20 is L1, the length W ₁₁₀ of the first lumen 110 is the length of the guide wire 50 on the straight line L1. is preferably 2 times or less, more preferably 1.7 times or less, even more preferably 1.4 times or less, and preferably 1.1 times or more, 1.2 times or more of the length _W50 defined by the outer edge of is more preferred. If the length _W110 of the first lumen 110 is within the above range, the size of the space formed between the outer edge of the guidewire 50 and the wall of the first lumen 110 is within a predetermined range with respect to the diameter of the guidewire 50. Therefore, the slidability of the guide wire 50 within the first lumen 110 can be improved.

As shown in FIG. 4, in a cross section perpendicular to the longitudinal axis direction x, when the straight line connecting the centroid P1 and the centroid P2 of the outer edge of the tube 20 is L1, and the straight line perpendicular to the straight line L1 is L2, the shaft 10 has a third position S3 where the lumen 100 of the shaft 10 has the minimum width by the regulation part 40 in the direction parallel to the straight line L2. When a line segment parallel to the straight line L2 is L3, the outer edge of the tube 20 is in contact with the line segment L3, or has a portion on the opposite side of the centroid P2 of the outer edge of the tube 20 with respect to the line segment L3. preferably. That is, it is preferable that the outer edge of the tube 20 has a portion that is in contact with the line segment L3 or protrudes toward the first lumen 110 with respect to the line segment L3. Since the position where the inner cavity 100 of the shaft 10 becomes the minimum width by the restricting portion 40 in the direction parallel to the straight line L2 is the position where the most protruding portion 41 of the restricting portion 40 exists, the line segment L3 is the length of the shaft 10. A line segment connecting the maximum projecting portion 41 of the projecting portion 40 provided on one side with respect to the straight line L1 of the lumen 100 and the maximum projecting portion 41 of the restricting portion 40 provided on the other side with respect to the straight line L1. It can be said that there is.

For the above configuration, as shown in FIG. 4, it is preferable that both the tube 20 and the guide wire 50 have a circular outer shape in a cross section perpendicular to the longitudinal axis direction x. With such a configuration, the guide wire 50 inserted through the first lumen 110 and the tube 20 can make point contact in a cross section perpendicular to the longitudinal axis direction x, so that the guide wire 50 slides in the first lumen 110. The resistance when moving is reduced, and the slidability of the guide wire 50 can be improved.

Alternatively, if the restricting portion 40 is provided only on one side with respect to the straight line L1, a straight line L2 connecting the restricting portion 40 on one side and the wall of the bore 100 of the shaft 10 on the other side at the third position S3. When a line segment parallel to is L3, the outer edge of the tube 20 is in contact with the line segment L3 or has a portion that exists on the opposite side of the centroid P2 of the outer edge of the tube 20 with respect to the line segment L3. is preferred.

In FIG. 4, the shaft 10 has a regulating portion 40 formed between the first position S1 and the second position S2 by making the wall thickness of the shaft 10 thicker than the wall thickness at the second position S2. However, even if the restricting portion 40 is provided by a separate member as shown in FIG. A position where 100 has a minimum width can be defined as a third position S3. It is preferable to have a portion that is in contact with the line segment L3 or located on the opposite side of the centroid P2 of the outer edge of the tube 20 with respect to the line segment L3.

Alternatively, if the restricting portion 40, which is a separate member, is provided only on one side of the straight line L1, the restricting portion 40 on one side and the wall of the bore 100 of the shaft 10 on the other side are separated at the third position S3. When a line segment parallel to the connecting straight line L2 is L3, the outer edge of the tube 20 has a portion that is in contact with the line segment L3 or exists on the opposite side of the centroid P2 of the outer edge of the tube 20 with respect to the line segment L3. preferably.

As shown in FIG. 5, in a cross section perpendicular to the longitudinal axis direction x, when a straight line connecting the centroid P1 and the centroid P2 of the outer edge of the tube 20 is L1, and a straight line perpendicular to the straight line L1 is L2, the shaft 10 has a third position S3 where the lumen 100 of the shaft 10 has the minimum width by the regulation part 40 in the direction parallel to the straight line L2. Assuming that a line segment parallel to the straight line L2 is L3, the outer edge of the tube 20 preferably does not have a portion on the opposite side of the centroid P2 with respect to the line segment L3. That is, it is preferable that the outer edge of the tube 20 does not have a portion protruding toward the first lumen 110 with respect to the line segment L3.

For the above configuration, as shown in FIG. 5, the first lumen 110 is formed in a circular shape in a cross section perpendicular to the longitudinal axis direction x, and the portion of the tube 20 facing the first lumen 110 is recessed. It preferably has an oval shape, and the second lumen 120 preferably has a shape that follows the outer shape of the tube 20 . With such a configuration, the guide wire 50 can be easily accommodated in the recess of the tube 20, and even when the shaft 10 is rotated around the central axis, the guide wire 50 is less likely to sway in the radial direction y. It becomes easier to improve the transferability.

Alternatively, if the restricting portion 40 is provided only on one side with respect to the straight line L1, a straight line L2 connecting the restricting portion 40 on one side and the wall of the bore 100 of the shaft 10 on the other side at the third position S3. When a line segment parallel to is defined as L3, the outer edge of the tube 20 preferably does not have a portion that exists on the opposite side of the centroid P2 of the outer edge of the tube 20 with respect to the line segment L3.

In FIG. 5, the inner lumen 100 of the shaft 10 is formed between the first position S1 and the second position S2 so that the wall thickness of the shaft 10 is thicker than the wall thickness at the second position S2. 3, even if the restricting portion 40 is provided by a separate member as shown in FIG. 3, the shaft A third position S3 can be defined as the position where the lumen 100 of 10 has the minimum width. Preferably, the outer edge of tube 20 does not have a portion lying on the opposite side of centroid P2 of the outer edge of tube 20 with respect to line L3.

Alternatively, if the restricting portion 40, which is a separate member, is provided only on one side of the straight line L1, the restricting portion 40 on one side and the wall of the bore 100 of the shaft 10 on the other side are separated at the third position S3. When a line segment parallel to the connecting straight line L2 is L3, it is preferable that the outer edge of the tube 20 does not have a portion on the opposite side of the centroid P2 of the outer edge of the tube 20 with respect to the line segment L3.

A hydrophilic coating or a hydrophobic coating is preferably applied to the portion of the outer wall of the tube 20 facing the first lumen 110 . The portion of the outer wall of the tube 20 facing the first lumen 110 is a portion that may come into contact with the guide wire 50 inserted through the first lumen 110. Therefore, by coating this portion, the guide wire 50 slidability can be improved. Hydrophilic coating or hydrophobic coating can be performed by immersing the tube 20 in a hydrophilic coating agent or a hydrophobic coating agent, applying a hydrophilic coating agent or a hydrophobic coating agent to the outer wall of the tube 20, or applying a hydrophilic coating agent or a hydrophobic coating agent to the outer wall of the tube 20. It can be applied by coating with a hydrophilic coating agent or a hydrophobic coating agent. Depending on the material forming the guide wire 50, a coating agent that can reduce the resistance with the material may be selected.

Examples of the hydrophilic coating agent used for the portion of the outer wall of the tube 20 facing the first lumen 110 include hydrophilic polymers such as polyvinyl alcohol, polyethylene glycol, polyacrylamide, polyvinylpyrrolidone, and methyl vinyl ether maleic anhydride copolymer, or Hydrophilic coating agents made from any combination thereof and the like are included.

Hydrophobic coating agents used for the portion of the outer wall of tube 20 facing first lumen 110 include polytetrafluoroethylene (PTFE), fluoroethylene propylene (FEP), silicone oil, hydrophobic urethane resin, carbon coat, A diamond coat, a diamond-like carbon (DLC) coat, a ceramic coat, and a substance terminated with an alkyl group or a perfluoroalkyl group and having a small surface free energy can be used.

The wall of the lumen 100 of the shaft 10 forming the first lumen 110 is preferably coated with a hydrophilic coating or a hydrophobic coating. The wall of the lumen 100 of the shaft 10 that forms the first lumen 110 is a portion that may come into contact with the guide wire 50 that is passed through the first lumen 110. The slidability of the wire 50 can be enhanced. Hydrophilic coating or hydrophobic coating is applied by immersing the shaft 10 in a hydrophilic coating agent or a hydrophobic coating agent, applying a hydrophilic coating agent or a hydrophobic coating agent to the wall of the lumen 100 of the shaft 10, or applying a hydrophilic coating agent or a hydrophobic coating agent to the shaft. It can be applied by coating the walls of the 10 lumens 100 with a hydrophilic coating or a hydrophobic coating. Depending on the material forming the guide wire 50, a coating agent that can reduce the resistance with the material may be selected. A hydrophilic or hydrophobic coating that can be used on the wall of the lumen 100 of the shaft 10 that forms the first lumen 110 is a hydrophilic coating that can be applied to the portion of the outer wall of the tube 20 that faces the first lumen 110 . Reference can be made to coating agents or hydrophobic coating agents.

It is preferable that the inner wall of the tube 20 is coated with a hydrophilic coating or a hydrophobic coating. Hydrophilic coating or hydrophobic coating can be performed by immersing the tube 20 in a hydrophilic coating agent or a hydrophobic coating agent, applying a hydrophilic coating agent or a hydrophobic coating agent to the inner wall of the tube 20, or coating the inner wall of the tube 20. It can be applied by coating with a hydrophilic coating agent or a hydrophobic coating agent. Depending on the type of fluid flowing through the lumen of the tube 20, a coating agent that can reduce resistance to the fluid may be selected. This allows fluid to easily pass through the lumen of tube 20 . A hydrophilic coating agent or a hydrophobic coating agent that can be used for the inner wall of the tube 20 can refer to a hydrophilic coating agent or a hydrophobic coating agent that can be applied to a portion of the outer wall of the tube 20 facing the first lumen 110 .

As shown in FIG. 1, the balloon catheter 1 may have a hub 4 on the proximal side of the shaft 10, and the hub 4 may be provided with the fluid injection section 2 and the guidewire insertion section 3. . Since the balloon catheter 1 has a hub 4 having a fluid injection section 2 and a guidewire insertion section 3, it is possible to supply fluid to the inside of the balloon 30 to expand or contract the balloon 30 and to operate the guidewire 50. can be easily done. In addition to the so-called over-the-wire type in which the guide wire 50 is inserted from the distal side to the proximal side of the shaft 10 as shown in FIG. It can also be applied to a so-called rapid exchange type in which the guide wire 50 is inserted halfway from the side to the proximal side.

The joint between the shaft 10 and the hub 4 can be performed, for example, by means of adhesion, welding, or the like. Above all, it is preferable that the shaft 10 and the hub 4 are joined by adhesion. By bonding the shaft 10 and the hub 4 together, the shaft 10 and the hub 4 are configured such that, for example, the shaft 10 is made of a highly flexible material and the hub 4 is made of a highly rigid material. Since the joint strength can be increased even if the materials are different, the degree of freedom in selecting the materials that constitute the shaft 10 and the hub 4 can be improved.

Although not shown, the distal end of the balloon catheter 1 is preferably provided with a tip member. By providing the tip member, it is possible to prevent the distal end of the balloon catheter 1 from being damaged when it comes into contact with a biological organ such as a blood vessel wall or a lumen wall of an organ.

This application claims the benefit of priority based on Japanese Patent Application No. 2022-23389 filed on February 18, 2022. The entire contents of the specification of Japanese Patent Application No. 2022-23389 filed on February 18, 2022 are incorporated herein by reference.

1: Balloon catheter 2: Fluid injection part 3: Guide wire insertion part 4: Hub 10: Shaft 20: Tube 30: Balloon 40: Regulating part 41: Most protruding part 50: Guide wire 100: Lumen of shaft 110: First Lumen 120: Second lumen P1: Centroid of outer edge of shaft P2: Centroid of outer edge of tube L1: Straight line connecting P1 and P2: Straight line L2 perpendicular to L1: Line segment S1: First position S2: Second 2nd position S3: 3rd position _W20 : Length _W41 defined by the outer edge of the tube: Width _W50 of the lumen of the shaft at the point of maximum protrusion: Length _W110 defined by the outer edge of the guidewire: First lumen length x: longitudinal axis direction y: radial direction

Claims

A balloon catheter having a longitudinal distal end and a proximal end, comprising:
A shaft extending in the longitudinal direction and having a lumen, wherein the lumen of the shaft defines a second lumen extending in the longitudinal direction and a first lumen through which a guidewire is inserted. a shaft including;
a balloon positioned distally of the shaft;
a tube disposed in the second lumen;
In a cross section perpendicular to the longitudinal axis direction, the first lumen and the second lumen are in communication,
an outer wall of the tube abuts a wall of the second lumen;
In a cross section perpendicular to the longitudinal direction, the first lumen does not include the centroid P1 of the outer edge of the shaft,
The balloon catheter, wherein the shaft has a restriction portion that restricts movement of the tube from the second lumen to the first lumen.
In a cross section perpendicular to the longitudinal axis direction, when a straight line connecting the centroid P1 and the centroid P2 of the outer edge of the tube is L1, and a straight line perpendicular to the straight line L1 is L2, the restricting portion Between the first position where the maximum diameter of the first lumen is located and the second position where the maximum diameter of the second lumen is located in the direction parallel to the straight line L2, the wall thickness of the shaft is the first. 2. The balloon catheter of claim 1, wherein the wall thickness is greater than at two locations.
The balloon catheter according to claim 1 or 2, wherein the shaft and the tube are made of different materials.
The balloon catheter according to claim 1 or 2, wherein the stiffness of the tube is higher than the stiffness of the shaft.
The balloon catheter according to claim 1 or 2, wherein the stiffness of the tube is lower than the stiffness of the shaft.
In a cross section perpendicular to the longitudinal axis direction, the straight line connecting the centroid P1 and the centroid P2 of the outer edge of the tube is L1, and the straight line perpendicular to the straight line L1 is L2. In the direction parallel to the straight line L2, the restricting portion has a third position where the lumen of the shaft has a minimum width, and at the third position, the opposing lumen walls of the shaft are connected and parallel to the straight line L2. 3. When a line segment is L3, the outer edge of the tube has a portion that is in contact with the line segment L3 or exists on the opposite side of the centroid P2 with respect to the line segment L3. Balloon catheter as described.
In a cross section perpendicular to the longitudinal axis direction, when a line connecting the centroid P1 and the centroid P2 of the outer edge of the tube is L1, and a straight line perpendicular to the straight line L1 is L2, the shaft is aligned with the straight line L2. In the direction parallel to the straight line L2, the restricting portion has a third position where the lumen of the shaft has a minimum width, and at the third position, the opposing lumen walls of the shaft are connected and parallel to the straight line L2. 3. The balloon catheter according to claim 1 or 2, wherein when a line segment is L3, the outer edge of the tube does not have a portion on the opposite side of the centroid P2 with respect to the line segment L3.
The balloon catheter according to claim 1 or 2, wherein a portion of the outer wall of the tube facing the first lumen is coated with a hydrophilic coating or a hydrophobic coating.
The balloon catheter according to claim 1 or 2, wherein the lumen wall of the shaft forming the first lumen is coated with a hydrophilic coating or a hydrophobic coating.
3. The balloon catheter according to claim 1, wherein the inner wall of said tube is coated with a hydrophilic coating or a hydrophobic coating.