JP7282364B2 - Balloon catheter, method for folding balloon of balloon catheter, and balloon forming apparatus - Google Patents

Description

The present invention relates to a balloon catheter, a method for folding a balloon of a balloon catheter, and a balloon forming apparatus.

A balloon catheter having a bent portion has been proposed as a catheter suitable for indwelling along a curved blood vessel or lumen.

A balloon catheter having such a bent portion includes a long shaft composed of an inner tube and an outer tube, and a balloon provided on the distal end side of the shaft. The proximal end of the balloon is tightly secured and liquid-tightly secured to the outer tube and fed into the interior of the balloon through a space formed between the inner tube and the outer tube. A balloon catheter in which the balloon is expanded and contracted by fluid pressure, wherein the balloon is preformed so as to have a curved shape with a curved portion on the way from the proximal end side to the distal end side of the balloon. The balloon is molded into the curved shape by being expanded with a pressure that does not stretch the membrane of the balloon, and the balloon is folded and wrapped around the inner tube. A balloon catheter has been proposed, which is characterized in that it assumes a helical shape in a contracted state due to a contraction (Patent Document 1).

However, it has been very difficult to evenly spirally fold a balloon catheter having such a curved portion in a straight state. In addition, there is a problem that it is difficult to expand the balloon smoothly.

Japanese Patent No. 5015772

SUMMARY OF THE INVENTION Accordingly, the present invention has been made to solve the above-described problems, and is a balloon catheter having a curved balloon, which can be easily folded in a straight state while improving the expansion function during expansion of the balloon. and to provide a folding method.

The present invention employs the following means to achieve the above objects.

In the balloon catheter according to the present invention,
It comprises an elongated shaft consisting of an inner tube and an outer tube, and a balloon provided on the distal end side of the shaft and pre-molded to have a bent or curved shape, the distal end of the balloon being in contact with the inner tube. liquid-tightly affixed, the proximal end of the balloon being liquid-tightly affixed to the outer tube, and supplied to the interior of the balloon through a space formed between the inner tube and the outer tube. A balloon catheter in which the balloon is expanded and contracted by the pressure of a fluid,
The balloon is characterized in that the balloon is folded into the inner tube in a deflated state such that a plurality of wings including at least a concave side wing formed on the concave side of the bent or curved shape is formed.

When the balloon is to be folded, the air inside the balloon is released to make it contracted before folding. In this deflated state, the balloon catheter of the present invention is deflated to form wings, at least one of which is formed on the concave side in the flexed or curved state of the balloon to form a concave side wing. It is folded after being shrunk. By forming the concave side wing in this way, the concave side wing is likely to wrinkle when folded, and the balloon can be easily straightened. Therefore, the balloon can be straightened and can be easily folded.

Further, in the balloon catheter according to the present invention, the concave side wings may be in a contracted state such that at least some of the wings are longer than the other wings. .

By forming the concave side blades longer than the other blades, the concave side blades are easily wrinkled, the balloon can be easily straightened, and the straightened balloon can be easily folded.

Further, in the balloon catheter according to the present invention, the concave side wing may be formed longer than the convex side wing formed on the convex side of the bent or curved shape. .

By forming the concave side blades longer than the convex side blades, when the balloon is straightened, the concave side blades have a large amount of room for extension, so that the balloon can be straightened and folded easily. In particular, it is suitable when a stretchable material is used for the material of the balloon.

Further, in the balloon catheter according to the present invention, the convex side wings formed on the convex side of the bent or curved shape may be formed longer than the concave side wings. .

To make it easier to straighten a balloon while forming wrinkles on the convex side wings when the balloon is straightened by forming the convex side wings longer than the concave side wings, and to facilitate straightening and folding. can be done. In particular, it is suitable when a non-elastic material is used for the material of the balloon.

Further, in the balloon catheter according to the present invention, the concave side vanes are bent or curved in a portion other than 10% of the distal end and the proximal end with respect to the total length of the balloon catheter. It may be characterized in that the blades are formed to be long.

When the concave portion of the balloon is straightened, it is most stretched around the center of the concave side blades, so by forming the concave side blades in this area to be long, the balloon can be straightened. This makes it easier to keep the balloon straight when folded.

Furthermore, in the balloon catheter according to the present invention, the vanes other than the vanes on the concave side may be arranged on the convex side with respect to the inner tube.

By adopting such a configuration, the other blades are in the direction of contraction even when the balloon is straightened, so that the other blades can be prevented from hindering the straightening of the balloon.

Furthermore, the balloon catheter according to the present invention may be characterized in that the concave side vanes of the vanes are folded so as to form the outermost periphery.

By folding the concave side blades to the outermost periphery, the longest concave side blades are expanded when the liquid or gas for expansion is inserted, so the balloon is expanded smoothly without interference between the blades. can do.

Further, the method for folding the balloon of the balloon catheter according to the present invention includes:
An elongated shaft comprising an inner tube and an outer tube, and a balloon provided on the distal end side of the shaft and preformed to have a bent or curved shape, the distal end of the balloon being the inner tube. and the proximal end of the balloon is liquid-tightly fixed to the outer tube, supplying the inside of the balloon through a space formed between the inner tube and the outer tube. A method for folding a balloon of a balloon catheter in which the balloon is expanded and contracted by the pressure of applied fluid, characterized by comprising the following steps.
(1) The balloon of the balloon catheter is pressed from three directions, that is, the convex side of the curved or curved shape and the concave side of the curved or curved shape, and three wings are formed so that the wings on the concave side are the longest. process to do.
(2) straightening the bent or curved shape of the balloon of the balloon catheter;
(3) A step of folding the inner tube so that the concave side blade of the three blades is the outermost circumference.

By adopting such a folding method, it is possible to provide a balloon catheter having the folding method described above.

The present invention also provides a balloon forming device for a balloon catheter. The balloon molding device according to the present invention includes:
An elongated shaft comprising an inner tube and an outer tube, and a balloon provided on the distal end side of the shaft and preformed to have a bent or curved shape, the distal end of the balloon being the inner tube. and the proximal end of the balloon is liquid-tightly fixed to the outer tube, supplying the inside of the balloon through a space formed between the inner tube and the outer tube. In a balloon forming apparatus for forming to roll a balloon of a balloon catheter in which the balloon is expanded and contracted by the pressure of the applied fluid,
The molding device includes a mold for molding the balloon into a predetermined shape before folding,
A mold that is placed on the convex side of a balloon that is curved during molding, and has a concave portion along the convex curve of the inner tube in the balloon, and the cross section of the concave portion is formed in a chevron shape, a middle claw type in which a recessed groove formed in a concave shape in which the inner tube is arranged is formed over the entire length of the recessed part at the vertex;
When the curved balloon is pressed from the downward direction on one side, it has a convex portion that is curved along the inner tube inside the balloon, and is formed in a concave shape at the apex of which the inner tube is arranged. A back nail type in which a concave groove is formed over the entire length of the convex portion;
When the balloon is curved at the time of molding and is pressed from the other side downward direction, it has a convex portion that is curved along the inner tube inside the balloon, and is formed into a concave shape where the inner tube is arranged at the vertex of the convex portion. a front claw type in which a recessed groove is formed over the entire length of the convex portion;
characterized by comprising

By using such a balloon forming apparatus, the balloon can be easily folded into the shape of the balloon of the aforementioned balloon catheter.

According to the balloon catheter according to the present invention, even a curved balloon can be easily folded straight.

FIG. 1 is a side view of a balloon catheter 100 according to an embodiment. FIG. 2 is a side view showing a folded state of the balloon catheter 100 according to the embodiment. FIG. 3 is a cross-sectional view showing a contracted state before folding the balloon catheter 100 according to the embodiment. FIG. 4 is a cross-sectional view showing another embodiment of the contracted state before folding the balloon catheter 100 according to the embodiment. FIG. 5 is a cross-sectional view showing yet another embodiment of the balloon catheter 100 in a contracted state prior to folding. FIG. 6 is a cross-sectional view showing yet another embodiment of the balloon catheter 100 according to the embodiment in a contracted state prior to folding. FIG. 7 is a cross-sectional view showing yet another embodiment of the balloon catheter 100 according to the embodiment in a contracted state before being folded. FIG. 8 is a cross-sectional view showing yet another embodiment of the balloon catheter 100 in a contracted state prior to folding. FIG. 9 is a perspective view of the balloon molding device 200 when deflating the balloon catheter 100 according to the embodiment. FIG. 10 is a perspective view showing a mold of the balloon molding device 200 when deflating the balloon catheter 100 according to the embodiment. FIG. 11 is a diagram showing the shape of the wire 80 used for molding when contracting the balloon catheter 100 according to the embodiment.

Next, an embodiment of the balloon catheter 100 according to the present invention will be described in detail with reference to the drawings. It should be noted that the embodiments and drawings described below illustrate a part of the embodiments of the present invention, and are not used for the purpose of limiting to these configurations, and do not depart from the gist of the present invention. It can be changed as appropriate within the range.

FIG. 1 is a side view of a balloon catheter 100 according to an embodiment. FIG. 2 is a cross-sectional view taken along the line AA of FIG. 1, showing a state in which the balloon catheter 100 has been deflated by expelling gas before folding the balloon catheter 100. As shown in FIG.

A balloon catheter 100 according to this embodiment mainly includes an elongated shaft 10 and a balloon 20 provided on the distal end side of the shaft 10, as shown in FIG.

The shaft 10 has a double-tube structure of an inner tube 11 and an outer tube 12. A lumen 11a in the inner tube 11 is mainly used for passing a guide wire, and a lumen 11a between the inner tube 11 and the outer tube 12 is used. The lumen 12a is used as a space for introducing gas or liquid for expanding the balloon 20 (hereinafter also referred to as "expansion fluid"). The inner tube 11 extends to the distal end side of the balloon 20 and is liquid-tightly fixed to the distal end of the balloon 20 at or near the distal end, and the inner tube 11 is disposed within the balloon 20. there is The outer tube 12 extends to the proximal end side of the balloon 20, and the distal end of the outer tube 12 or the vicinity of the distal end and the proximal end of the balloon 20 are fixed in a liquid-tight manner.

The inner tube 11 is made of tubular resin such as high-density polyethylene, polyamide, polyimide, polyetheretherketone, polyethylene terephthalate, polyurethane, polypropylene, and fluorine resin.

The outer tube 12 is also made of tubular resin, and examples thereof include polyamide, polyethylene, polyimide, polyetheretherketone, polyethyleneterephthalate, polyurethane, and polypropylene.

The balloon 20 is formed of a hollow film-like body made of resin, and is formed so as to be expandable by pressure by injecting gas or liquid thereinto and to be contracted by suction. Balloons according to the present invention are molded to have a bent or curved shape when inflated. The torsion rate and curvature rate of the balloon are not limited, and can be appropriately selected according to the intended use. Examples of the material forming the balloon 20 include polyamide, polyamide elastomer, polyethylene terephthalate, polyester elastomer, polyurethane, and the like.

The balloon 20 and the inner tube 11 preferably have a positional relationship such that the inner tube 11 does not come into contact with the inner surface of the balloon 20 during expansion as shown in FIG. This is because if the balloon 20 and the inner tube 11 come into contact with each other, the expanded shape of the balloon 20 may be deformed because the inner tube 11 has higher rigidity than the balloon 20 .

Additionally, balloon catheter 100 optionally has one or more radiopaque markers 70 attached to inner tube 11 within balloon 20 so that the position and bending or bending state of balloon 20 can be ascertained. Also good.

Moreover, a connector 50 may be attached to the proximal end of the balloon catheter 100 for connection with a fluid supply device for inserting a guide wire into the balloon catheter 100 or for inserting dilation fluid. A known form of the connector 50 can be appropriately selected and used.

As shown in FIG. 2, the balloon catheter 100 thus manufactured is in a state in which the balloon 20 and the inner tube 11 are folded in a straight line and housed in a sheath or the like in the initial state before use for surgery or the like. available for use.

Here, a method for folding the balloon catheter 100 will be described.

(Folding method in first contracted state)
The balloon 20 of the balloon catheter 100 of the present invention is fabricated with the balloon 20 expanded rather than fully deflated after fabrication. The balloon 20 is folded from this state, but as shown in FIG. 3, it is necessary to discharge the air inside the balloon 20 so that it is deflated before folding. In the contracted state, the balloon 20 is pressed against the inner tube 11 side, and the surplus balloon 20 has a plurality of wings (21, 22, 23) extending radially. The extended portions (21, 22, 23) of the balloon 20 are referred to as "wings" in this specification and claims. In FIG. 3, the blades are shown spaced apart for easy understanding, but they are actually formed so as to overlap each other exactly. Further, the length of the blade refers to the distance from the central portion of the radially formed blade, as shown in FIG. In this embodiment, three vanes (21, 22, 23) are shown, but the number of vanes is not limited to three. One of the vanes (21, 22, 23) is formed with a concave side vane 21 located on the concave side of the curved balloon 20 (lower side in FIG. 3). As shown in FIG. 1, the concave side blades 21 refer to blades that are on the concave side with respect to the temporary center line (θ in the figure) of the balloon 20 when viewed from the side of the curved balloon 20. The convex side blades 22 and 23 refer to blades on the convex side with respect to the provisional center line (θ in the drawing) of the balloon 20 . The concave side blades 21 are formed in the direct downward direction in FIG. 3, but the direct downward direction is not necessarily required, and as shown in FIG. 4, a certain angle may be formed. At this time, in the first contracted state, the length α from the center of the concave side blade 21 is longer than the length β of the convex side blades 22 and 23 as shown in FIG. By forming the concave side blades 21 in this way, if a relatively soft material is used for the material of the balloon 20, wrinkles will be formed. Therefore, the balloon 20 can be easily straightened in a deflated state, and the blades (21, 22, 23) can be easily folded. Further, when a stretchable material is used for the material of the balloon 20, since the concave side blades 21 are formed long, the expansion margin becomes large and the blades 21 and 22 can be easily straightened. , 23 can be folded. When folding, if the concave side blades 21 are formed long, it is preferable to fold the concave side blades 21 to the outermost side. By folding in this way, when expanding the balloon 20, the largest concave side blade 21 can be expanded first, so the other blades 22 and 23 can be smoothly expanded without interfering with each other. Furthermore, it is preferable to arrange all the blades 22 and 23 other than the concave side blade 21 on the convex side of the balloon 20 from the center of the inner tube 11 . By forming the balloon 20 in this manner, the blades 22 and 23 other than the concave side blade 21 are contracted when the balloon 20 is straightened. The range in which this concave side blade 21 is longer than the other blades 22 and 23 is preferably formed in a position other than the range of 10% of the total length of the balloon 20 from the proximal end and distal end of the balloon 20 . This is because when the balloon 20 is straightened, the concave side vanes 21 are less likely to obstruct the vicinity of the distal end and the proximal end of the balloon 20 because the curvature is not corrected so much. In addition, as shown in FIG. 5, the blades may be pre-curved in the folding direction so that the blades can be easily folded.

(Folding method in second contracted state)
In the second deflated state, as shown in FIG. 6, at least one of the vanes (21, 22, 23) has a convex side (21, 22, 23) positioned on the convex side (upper side in FIG. 3) of the curved balloon 20. shaped side blades 22 and 23 are formed. At this time, the length β from the center of some or all of the convex side blades 22 and 23 is longer than the length α of the concave side blade 21 . By forming the convex side wings 22 and 23 long in this way, wrinkles are more likely to occur in the convex side wings 22 and 23 when the balloon 20 is straightened, and the balloon 20 is made of a relatively rigid material. Even in the case of Therefore, the blades (21, 22, 23) can be easily folded. When folding, it is preferable to fold one of the convex side blades 22 and 23 so as to be on the outermost side. By folding the balloon 20 in this way, the large convex side wings 22 and 23 can be expanded first when expanding the balloon 20, so that the other blades can be smoothly expanded without interfering with each other. In the case of forming three blades, as shown in FIG. 7, the convex side blades 22 and 23 and the angle δ may be formed so that the angle γ formed by is small. By forming in this way, the convex side wings 22 and 23 are arranged in a direction in which wrinkles are more likely to occur, so the balloon 20 can be made straighter. In addition, the range in which the convex side wings 22 and 23 are longer than the concave side wings 21 should be formed in a position other than the range of 10% of the total length of the balloon 20 from the proximal end and the distal end of the balloon 20. is preferred as in the first contraction state.

In both the first contracted state and the second contracted state, the inner tube 11 does not necessarily have to be in the central portion of the contracted state, and may be arranged in the blade portion as shown in FIG.

Next, a molding method for molding the contracted state of the balloon 20 of the balloon catheter 100 will be described. First, the balloon forming apparatus 200 for forming the shape of the balloon 20 before folding will be described. A perspective view of an embodiment of a balloon shaping device 200 for use in folding the balloon catheter 100 of the present invention is shown in FIG. The balloon molding apparatus 200 mainly includes molds 211, 212, and 213 for molding the balloon 20 into a predetermined shape before folding, and clamps arranged at the proximal end side and the distal end side for fixing the balloon catheter 100. 220.

The mold consists of a middle claw mold 211 , a back claw mold 212 and a front claw mold 213 . The middle claw mold 211 is a mold that is arranged on the convex side of the balloon 20 that is curved at the time of molding, and as shown in FIG. The cross section of the recessed portion 211a is formed in a mountain shape, and a recessed groove 211b in which the inner pipe 11 is arranged is formed over the entire length of the recessed portion 211a at the top of the recessed portion 211a. As shown in FIG. 10B, the back nail mold 212 is pressed against the balloon 20, which is curved at the time of molding, from one side and the downward direction of the inner tube 11 so as to follow the inner tube 11 inside the balloon 20. It has a curved convex portion 212a, and a concave groove 212b in which the inner pipe 11 is arranged is formed over the entire length of the convex portion 212a. The front nail mold 213 has a convex portion 213a that curves along the inner tube 11 of the balloon 20 when pressed from the lower side on the other side surface of the balloon 20, which is curved at the time of molding. A recessed groove in which the inner pipe 11 is arranged is formed at the vertex over the entire length of the protruded portion 213a. Since the front nail mold 213 is manufactured symmetrically with respect to the back nail shape, its illustration is omitted. As shown in FIG. 9, the mold thus produced has a middle nail mold 211 arranged on the convex side of the curve of the balloon 20, and a back nail mold 212 and a front claw mold 213 positioned laterally and downwardly. , and formed to be radially movable with respect to the inner tube 11 . When the molds are clamped with the balloon 20 arranged, the inner tube 11 is supported by the back nail mold 212 and the front nail mold 213, and the inner tube 11 pushes the balloon 20 toward the middle nail mold 211 inside the balloon 20. Made to shrink.

The clamp 220 is a member that clamps and fixes the distal end side and the proximal end side of the balloon 20 when the balloon catheter 100 is attached to the mold. Any form may be used as long as the distal end side and the proximal end side of the balloon catheter 100 can be fixed. In this embodiment, it is fixed by sandwiching it between the upper mold 220a and the lower mold 220b.

A method for forming the contracted state of the balloon 20 of the balloon catheter 100 using the balloon forming apparatus 200 configured in this way will be described.

When the balloon catheter 100 is manufactured, it is in a state in which gas is inserted into the balloon catheter 100 and is in an expanded state. The balloon catheter 100 is set in the balloon molding device 200 from this state. At this time, as shown in FIG. 11, a wire 80 bent to match the curvature of the balloon and provided with a clamping support portion 81 at its tip to be sandwiched between clamps is inserted into the inner tube 11 to fix the shape. good. By tightening the mold from this state, the balloon 20 is pushed from three directions to form vanes extending in three directions between the molds. At this time, by quickly pressing the middle claw mold 211 against the back claw mold 212 and the front claw mold 213, the concave side blade 21 is formed long, and the middle claw mold 211 is formed into the back claw mold 212 and the front claw mold 213. By pressing slowly against, the convex side wings 22, 23 can be made longer. By discharging the internal gas in this state, vanes are formed in three directions, and the contracted balloon 20 is molded. From this state, the blades 21, 22, and 23 are folded or wound along the inner tube 11 while the balloon 20 is straightened, so that the balloon can be wound while maintaining the straightness.

The balloon catheter 100 manufactured as described above is used as follows. While introducing a guide wire that has been inserted and indwelled in the blood vessel in advance into the inner tube 11 . The balloon catheter 100 is inserted along the guidewire to the target position. The blood vessel or lumen at the target location of the balloon catheter 100 according to the present invention becomes a curved portion. During this insertion, the balloon 20 is straight, not curved. When the balloon reaches the target position, a balloon expansion fluid is supplied to expand the balloon 20 . When the fluid for expanding the balloon is supplied to the inside of the balloon 20, the blades arranged on the outermost side are unraveled first. Fluid is applied and the whole is gradually unfolded to expand into a bent or curved shape, as shown in FIG.

As described above, according to the balloon catheter 100 of the present invention, the shape of the balloon 20 is curved when inflated. Even if there is, the balloon 20 can be indwelled according to the expanded shape of the balloon 20, and uniform pressure can be applied to the walls of curved blood vessels and lumens.

It goes without saying that the present invention is by no means limited to the above-described embodiments, and can be embodied in various forms as long as they fall within the technical scope of the present invention.

As shown in the embodiment described above, it can be used as a balloon catheter.

DESCRIPTION OF SYMBOLS 10... Shaft, 11... Inner tube, 11a... Lumen, 12... Outer tube, 12a... Lumen, 20... Balloon, 21... Concave side wing, 22... Convex side wing, 50... Connector, 70... X-ray opaque marker , 80... Wire, 81... Supporting part for clamp, 100... Balloon catheter, 200... Balloon molding device, 211... Intermediate nail type, 211a... Concave part, 211b... Concave groove, 212... Back nail type, 212a... Convex part , 212b... concave groove, 213... front claw type, 213a... convex portion, 220... clamp, 220a... upper die, 220b... lower die

Claims (4)

It comprises an elongated shaft consisting of an inner tube and an outer tube, and a balloon provided on the distal end side of the shaft and pre-molded to have a bent or curved shape, the distal end of the balloon being in contact with the inner tube. liquid-tightly affixed, the proximal end of the balloon being liquid-tightly affixed to the outer tube, and supplied to the interior of the balloon through a space formed between the inner tube and the outer tube. A balloon catheter in which the balloon is expanded and contracted by the pressure of a fluid,
A plurality of vanes extending in the radial direction are formed in a contracted state in which the balloon is pressed against the inner tube side, and the vanes are convex radially formed on the convex side with respect to the temporary center line of the curved balloon. having a side wing and one concave side wing located on the concave side;
A balloon catheter according to claim 1, characterized in that a material of said balloon has elasticity, and said concave side wings are formed longer than said convex side wings. The concave side wing is formed so that the concave side wing on the bent or curved concave side is longer than 10% of the distal end and the proximal end with respect to the total length of the balloon. 2. The balloon catheter of claim 1, comprising: 3. The balloon catheter according to claim 1, wherein said concave side wings are folded so as to form the outermost periphery. A method for folding a balloon of a balloon catheter according to any one of claims 1 to 3, characterized by comprising the following steps.
(1) The balloon of the balloon catheter is pressed from three directions, that is, the convex side of the curved or curved shape and the concave side of the curved or curved shape, and three wings are formed so that the wings on the concave side are the longest. process to do.
(2) straightening the bent or curved shape of the balloon of the balloon catheter;
(3) A step of folding the three blades into the inner tube so that the blade on the concave side becomes the outermost circumference.

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