JP2020171601A - Balloon catheter - Google Patents

Abstract

To provide a balloon catheter, when a balloon is deflated for being stored in a sheath, capable of improving a passing property thereof in the narrow sheath by causing a user to compress a stretching part at the hand to extend the balloon and remove creases.SOLUTION: A balloon catheter 100 according to the present invention, comprises an elongated shaft 10 consisting of an inner tube 11 and an outer tube 12, and a balloon 20, where the balloon includes a distal end that is joined with the inner tube and a proximal end that is joined with the outer tube, and the balloon is inflated and deflated by a pressure of a fluid supplied to the inside of the baloon via a space formed between the inner tube and the outer tube. The balloon catheter is characterized by including a stretching part 30 between the outer tube and the hand side, for allowing the outer tube to move in the axial direction, with respect to the inner tube.SELECTED DRAWING: Figure 1

Description

The present invention relates to a balloon catheter.

In a balloon catheter, the removable diameter may be larger than the insertable diameter. A typical example is a balloon catheter used in the aorta, one for touch-up that mainly aims to crimp the inner wall of the blood vessel of the stent graft placed in the aorta, and the other that occludes the inside of the blood vessel and controls blood flow. Occlusion (for occlusion) and balloon catheters for IAB are known.

In the case of balloon catheters for stent graft expansion and balloon catheters for occlusion used in the aorta, it is necessary to greatly expand the balloon in order to make a wide range of contact so that the balloon adheres to the inner wall in the blood vessel or in the stent graft. A balloon having a large expansion diameter and a large injection capacity of an expansion medium is used as compared with other balloon catheters for endovascular treatment.

On the other hand, when inserting a catheter, a sheath as thin as possible is required as long as the performance is not affected from the viewpoint of minimal invasiveness.

To meet this conflicting requirement, the balloon is generally made of a highly extensible material, the balloon membrane is also formed as thin as possible, and it is folded thin to improve the sheath passage during insertion. I am using the one that is wrapped.

However, when a sheath with the smallest diameter into which a thinly folded balloon can be inserted is used, once the balloon is expanded in a blood vessel or the like, the wrapping state is released, so the balloon is pulled back into the sheath when it is removed. If the balloon cannot be removed from the body, it must be removed with the sheath.

Therefore, if you need to insert another catheter after using the balloon catheter, or if you need to remove the balloon several times during treatment, you have to choose a thick sheath that allows the balloon catheter to be inserted from the beginning. There was a problem of not getting.

In addition, in order to avoid this, a balloon catheter may be inserted directly into the blood vessel without a sheath. Even in this case, there is a problem that it is difficult to pull out the balloon when it is pulled out once the balloon that has been expanded and contracted becomes large.

In addition, during use, in order to bring the balloon into close contact with the inner wall inside the blood vessel or stent, the balloon may be expanded (hyperinflated) far beyond the volume (standard diameter) at the time of molding. In this case, after the balloon comes into contact with the inner wall of the blood vessel, it is restricted by the inner wall and does not become larger in the radial direction, but because it is an extensible material, it tries to expand in the unregulated axial direction. At this time, the membrane of the balloon may be inverted at the joint with the inner tube and the outer tube and may overlap with the tubular portion of the distal portion and the proximal portion (see FIG. 5). In this case, even if an extensible material is used, if the balloon is inflated excessively, it will undergo plastic deformation and will not return to its original shape. Even if the catheter is subjected to negative pressure in this state and the balloon is contracted, there is a problem that the balloon portion overlaps with the tubular portion in the distal portion or the proximal portion and the outer diameter becomes thick, making it difficult to pass through the sheath.

Furthermore, since IAB is left in the body for a long period of time due to the characteristics of the product, a thin sheath is desired so as not to interfere with peripheral blood circulation. Although it is not intentionally overinflated, the thickness of the balloon is made as thick as possible due to durability issues. Therefore, the balloon is neatly wrapped to allow it to pass through the sheath before insertion. After use, the balloon is inflated and cannot be folded neatly inside the body, making it difficult to pass through the sheath, which is also usually removed with the sheath.

In order to leave the sheath for later treatment or use of hemostatic devices, a sheath larger than the insertable size must be selected before use, but even in that case, the resistance when passing through the sheath is large, especially. In the case of IAB, the balloon length was long, the resistance in the sheath increased, and the balloon was gradually stretched and biased to the distal side, which sometimes made it difficult to remove.

Regarding this problem, the stainless rod inserted into the catheter tube is joined to the distal side of the balloon, and the outer tube is joined to the proximal side of the balloon, so that the stainless rod slides and contracts when the balloon is extended. A balloon catheter has been proposed in which wrinkles are smoothed by increasing the diameter and the passage through the sheath is improved (Patent Document 1).

However, such a balloon catheter has a structure in which the inner tube and the outer tube are not fixed, the inner tube penetrates the outer tube, and the inner tube can rotate freely with respect to the outer tube. The balloon can be easily wound by rotating it, but it is necessary to establish an inner tube that penetrates the outer tube, fix the inner tube when the balloon is expanded, and prevent leakage of the expansion medium. Therefore, there is a problem that the structure becomes complicated and the manufacturing process becomes complicated. Further, there is a problem that it is necessary to adjust the fixed position of the inner during the treatment according to the work.

Japanese Unexamined Patent Publication No. 11-169463

Therefore, the present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a balloon catheter capable of easily storing a balloon catheter expanded in the body in a thin sheath. To do.

The present invention has taken the following measures to achieve the above object.

The balloon catheter according to the present invention
It has a long shaft consisting of an inner tube and an outer tube, and a balloon.
The balloon is formed between the inner tube and the outer tube by directly or indirectly joining the distal end to the inner tube and directly or indirectly joining the proximal end to the outer tube. In a balloon catheter in which the balloon expands and contracts due to the pressure of the fluid supplied to the inside of the balloon through the space provided.
The outer pipe is characterized by having an expansion / contraction portion between the outer pipe and the hand side so that the outer pipe can be moved in the axial direction with respect to the inner pipe.

By adopting such a configuration, the inner tube connected to the distal end of the balloon and the inner tube connected to the proximal end of the balloon can be moved in the axial direction, so that the proximal part of the balloon can be moved. The distance between the ends and the distal ends can be changed. Therefore, when the balloon is contracted to be housed in the sheath, the user can compress the elastic part at hand to stretch the balloon and remove wrinkles, and improve the passageability with a thin sheath. .. That is, it can be contracted thinner, and the balloon can be stored in a thinner sheath.

Further, in the balloon catheter according to the present invention, the telescopic portion may be characterized by having a bellows structure, a Miura fold structure or a spiral structure.

By forming such a telescopic portion, the outer pipe can be efficiently moved with respect to the inner pipe.

Further, in the balloon catheter according to the present invention, the telescopic portion may be characterized by including a spring member that assists the expansion and contraction.

By adopting such a configuration, the outer tube can be urged in a certain direction, so that the distance between the proximal end and the distal end of the balloon catheter can be adjusted by operating only in one direction.

Further, in the balloon catheter according to the present invention, the expansion / contraction portion may be provided with a stopper for holding the expansion / contraction state.

By adopting such a configuration, the distance between the distal end and the proximal end of the balloon can be fixed at a constant distance, so that a balloon catheter that is easier to use can be obtained.

Further, in the balloon catheter according to the present invention, the telescopic portion may be arranged on the outer peripheral side of the outer tube.

By adopting such a configuration, when the chemical solution or the like is injected, the chemical solution or the like does not come into direct contact with the elastic part, so that the unevenness due to the inner surface of the elastic part disturbs the flow of the chemical solution or the like when the chemical solution or the like is injected. Can be prevented.

Further, in the balloon catheter according to the present invention, the telescopic portion may be characterized in that the telescopic portion has a tapered shape in the axial direction.

By forming the taper shape, either the distal end or the proximal end can be thickened, so that the telescopic portion can be easily operated.

Further, the balloon catheter according to the present invention may be characterized in that a connector is provided at the proximal end of the shaft, and the telescopic portion is arranged adjacent to the connector.

By adopting such a configuration, the telescopic portion is arranged near the connector, so that it is easy to operate on the hand side and can be operated with one hand.

According to the balloon catheter according to the present invention, when the balloon is contracted to be housed in the sheath, the user compresses the elastic part at hand to stretch the balloon to remove wrinkles, and the thin sheath is used. It is possible to provide a balloon catheter that can improve the passage.

FIG. 1 is a schematic view of the balloon catheter 100 according to the first embodiment. FIG. 2 is a schematic view showing an example of the configuration of the telescopic portion 30 of the balloon catheter 100 according to the first embodiment. FIG. 3 is a schematic view showing an example of the configuration of the telescopic portion 30 of the balloon catheter 100 according to the first embodiment. FIG. 4 is a schematic view showing a state in which the telescopic portion 30 of the balloon catheter 100 according to the first embodiment is contracted. FIG. 5 is a schematic view showing a state in which the balloon 20 is over-expanded. FIG. 6 is a schematic view showing the telescopic portion 30 of the balloon catheter 100 according to the second embodiment. FIG. 7 is a schematic view showing the telescopic portion 30 of the balloon catheter 100 according to the third embodiment. FIG. 8 is a schematic view showing the telescopic portion 30 of the balloon catheter 100 according to the fourth embodiment. FIG. 9 is a schematic view showing the telescopic portion 30 of the balloon catheter 100 according to the fifth 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 exemplify a part of the embodiments of the present invention, are not used for the purpose of limiting to these configurations, and do not deviate from the gist of the present invention. It can be changed as appropriate within the range. For convenience of explanation, in the claims and the specification, the "distal end" and the "proximal end" refer to the hand side with respect to the balloon catheter 100 as the "proximal end", and the tip thereof. The side is called the "distal end".

The balloon catheter 100 according to the first embodiment is mainly provided on a long shaft 10 including an inner tube 11 and an outer tube 12 and a distal end side of the shaft 10, as shown in FIGS. 1 and 2. The balloon 20 and the telescopic portion 30 provided on the shaft 10 are provided.

The shaft 10 has a double pipe structure of an inner pipe 11 and an outer pipe 12, and the lumen 11a in the inner pipe 11 is mainly used for passing a guide wire, and is between the inner pipe 11 and the outer pipe 12. The lumen 12a of the above is mainly used as a space for introducing an expansion fluid for expanding the balloon 20. The inner tube 11 extends to the distal end side of the balloon 20 and is liquidtightly joined to the distal end side of the balloon 20 directly or indirectly via a ring near the distal end or the distal end, and the inner tube 11 is formed. 11 is arranged in the balloon 20. The outer tube 12 extends to the proximal end side of the balloon 20, and the distal end or the vicinity of the distal end of the outer tube 12 and the proximal end of the balloon 20 are joined directly or indirectly via a ring in a liquid-tight manner. Has been done. The inner pipe 11 and the outer pipe 12 are provided so that their relative positions can be changed in the axial direction.

The inner tube 11 is made of a tubular resin, and examples thereof include high-density polyethylene, polyamide, polyimide, polyetheretherketone, polyethylene terephthalate, polyurethane, polypropylene, and fluororesin.

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

The balloon 20 is formed of a resin-made film-like hollow body, and is formed to expand by pressure by supplying an expansion fluid composed of gas or liquid to the inside, and to be contractible by suction. .. Examples of the material constituting the balloon 20 include polyamide, polyamide elastomer, polyethylene terephthalate, polyester elastomer, and polyurethane.

The telescopic portion 30 is attached to a part of the outer tube 12 of the balloon 20 as shown in FIG. The telescopic portion 30 has a tubular body formed continuously so as to be sealed with respect to the outer tube 12, or a tapered shape in which either the distal end side or the proximal end is formed thinner than the other. It is formed. It is preferable to provide the telescopic portion 30 at a position within 10 cm from the hand side so that the telescopic portion 30 can be easily operated. By extending or contracting the telescopic portion 30 in the axial direction, the position of the outer pipe 12 on the distal end side of the telescopic portion 30 with respect to the inner pipe 11 can be moved in the axial direction.

The form of the telescopic portion 30 is not particularly limited as long as the position of the outer tube 12 on the distal end side of the telescopic portion 30 can be moved, but for example, as shown in FIG. It may be formed into a structure, a spiral structure as shown in FIG. 2B, or a so-called Miura fold structure (including a PCCP shell structure) as shown in FIG.

The balloon catheter 100 produced in this manner has an inner tube 11 connected to the distal end of the balloon 20 and a proximal of the balloon 20 by making the telescopic portion 30 contract in the axial direction or in the stretched state. Since the axial relative position with respect to the outer tube 12 connected to the end can be changed, the distance between the distal end and the proximal end of the balloon 20 can be changed.

By using such a balloon catheter 100, when the balloon 20 is expanded in the blood vessel, as shown in FIG. 4, when the balloon 20 at the tip is axially overinflated, the expansion / contraction portion 30 is axially contracted. By causing an axial displacement between the inner tube 11 and the outer tube 12, even when the balloon membrane widely contacts the inner wall 80 of the blood vessel, the inner tube 11 and the outer tube 12 as shown in FIG. 5 It is possible to reduce overexpansion beyond the connection with the.

Further, when the balloon 20 is contracted, as shown in FIG. 5, the balloon 20 is excessively expanded beyond the overlap near the joint portion of the distal end or the proximal end of the balloon 20, and the balloon 20 is folded over the shaft 10. As shown in FIG. 4, the user compresses the telescopic portion 30 at hand even when the balloon 20 is stretched due to plastic deformation of the material of the balloon 20 to make it difficult to pass through the sheath. The balloon 20 can be stretched to remove wrinkles and improve passage with a thin sheath.

(Second Embodiment)
A partially enlarged view of the telescopic portion 30 of the balloon catheter 100 according to the second embodiment is shown in FIG. 6A. The configuration of the long shaft 10 composed of the inner pipe 11 and the outer pipe 12 according to the second embodiment, the balloon 20 provided on the distal end side of the shaft 10, and the telescopic portion 30 provided on the shaft 10 Since it is the same as the first embodiment, the description thereof will be omitted.

The second embodiment is different from the first embodiment in that the telescopic portion 30 is provided with a spring member 60 that assists the expansion and contraction. By providing the spring member 60 in the telescopic portion 30, the operability can be improved because it is only necessary to apply a force in one direction to move the telescopic portion 30. That is, when the spring member 60 for maintaining the stretchable portion 30 in the stretched state is provided in advance, the force needs to be applied only when the stretchable portion 30 is contracted, and when returning to the original state, the hand is released from the stretchable portion 30. By doing so, it can be automatically returned to the initial state.

When arranging the spring member 60 in the telescopic portion 30, as shown in FIG. 6B, a spiral shape is used for the telescopic portion 30, and the rotation pitch of the spring member 60 is set to the spiral pitch of the telescopic portion 30. By matching, the spring member 60 can be inserted into the spiral fold portion, and the spring member 60 having a larger outer diameter can be arranged. With such a configuration, the possibility that the spring member 60 becomes a resistance when injecting the expansion fluid can be reduced.

(Third Embodiment)
A partially enlarged view of the telescopic portion 30 of the balloon catheter 100 according to the third embodiment is shown in FIG. Since the configuration of the shaft 10 according to the third embodiment, the balloon 20 provided on the distal end side of the shaft 10, and the telescopic portion 30 provided on the shaft 10 is the same as that of the first embodiment, the description thereof will be omitted. To do.

In the third embodiment, the expansion / contraction portion 30 is provided with a stopper 70, and can be fixed at an arbitrary expansion / contraction ratio position according to the expansion / contraction state of the expansion / contraction portion 30. As the stopper 70, for example, as shown in FIG. 7, a clip or the like that holds both sides of the telescopic portion 30 and can adjust the distance between the holding portions on both sides to an arbitrary position can be considered. By providing such a stopper 70, after moving the expansion / contraction position of the expansion / contraction portion 30, the work can be performed without changing the expansion / contraction state even if the hand is released.

(Fourth Embodiment)
A partially enlarged view of the telescopic portion 30 of the balloon catheter 100 according to the fourth embodiment is shown in FIG. The shaft 10 of the balloon catheter 100 according to the fourth embodiment and the balloon 20 provided on the distal end side of the shaft 10 are the same as those of the first embodiment, and thus the description thereof will be omitted.

In the fourth embodiment, the telescopic portion 30 is arranged on the outer peripheral side of the outer tube 12, the proximal end of the telescopic portion 30 is connected adjacent to the connector 90 on the hand side, and the distal end side is the outer side. It is connected to a tubular member 35 formed by tightening the pipe 12 with a constant frictional force. Although the tubular member 35 can be moved by human power, it is tightened to such an extent that it cannot be moved by a normal balloon expansion / contraction operation, and has a function as a stopper.

In the balloon catheter 100 thus produced, a part of the outer tube 12 can enter the connector 90 by contracting the telescopic portion 30, and the relative position between the inner tube 11 and the outer tube 12 can be changed, and the balloon can be changed. The distance between the distal and proximal ends of 20 can be adjusted.

By adopting such a configuration, since the expansion fluid does not come into contact with the inner surface of the expansion / contraction portion 30, it is possible to prevent the fluid flow from being disturbed due to the unevenness of the inner surface of the expansion / contraction portion 30.

(Fifth Embodiment)
A partially enlarged view of the telescopic portion 30 of the balloon catheter 100 according to the fifth embodiment is shown in FIG. Since the balloon 20 related to the balloon catheter 100 according to the fifth embodiment is the same as that of the first embodiment, the description thereof will be omitted.

In the balloon catheter 100 according to the fifth embodiment, the outer tube 12 of the shaft 10 is formed by being divided into two at the telescopic portion 30, and one outer tube 12c is inserted inside the other outer tube 12b. It is formed like this. By adopting such a configuration, the telescopic portion 30 can be arranged on the outer peripheral side of the outer pipe 12. Therefore, since the expansion fluid does not come into contact with the inner surface of the expansion / contraction portion 30, it is possible to prevent the flow of the fluid from being disturbed due to the unevenness of the inner surface of the expansion / contraction portion 30.

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

10 ... shaft, 11 ... inner tube, 11a ... lumen, 12 ... outer tube, 12a ... lumen, 12b ... outer tube, 12c ... outer tube, 20 ... balloon, 30 ... telescopic part, 35 ... tubular member, 60 ... spring Member, 70 ... Stopper, 80 ... Inner wall, 90 ... Connector, 100 ... Balloon catheter

Claims (7)

It has a long shaft consisting of an inner tube and an outer tube, and a balloon.
The balloon is formed between the inner tube and the outer tube by directly or indirectly joining the distal end to the inner tube and directly or indirectly joining the proximal end to the outer tube. In a balloon catheter in which the balloon expands and contracts due to the pressure of the fluid supplied to the inside of the balloon through the space provided.
The balloon catheter is characterized in that the outer tube is provided with a telescopic portion between the outer tube and the hand side so that the outer tube can be moved axially with respect to the inner tube. The balloon catheter according to claim 1, wherein the telescopic portion has a bellows structure, a Miura fold structure, or a spiral structure. The balloon catheter according to claim 1 or 2, wherein the telescopic portion includes a spring member that assists the expansion and contraction. The balloon catheter according to any one of claims 1 to 3, wherein the telescopic portion includes a stopper for holding the stretched state. The balloon catheter according to any one of claims 1 to 4, wherein the telescopic portion is arranged on the outer peripheral side of the outer tube. The balloon catheter according to any one of claims 1 to 5, wherein the telescopic portion has a tapered shape in the axial direction. The balloon catheter according to any one of claims 1 to 6, wherein a connector is provided at a proximal end of the shaft, and the telescopic portion is arranged adjacent to the connector.

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