JP5002417B2 - Balloon catheter - Google Patents

Description

  The present invention relates to a balloon catheter that is used by being inserted into a living body at the time of performing an expansion treatment of a stenosis site or a blockage site of a blood vessel.

  Conventionally, balloon catheters have been used in treatments such as PTCA (percutaneous coronary angioplasty). For example, as shown in Patent Document 1 and Patent Document 2, a general balloon catheter is configured by joining a balloon that can be inflated and deflated by adjusting internal pressure to the distal end side of a catheter tube.

In addition, a balloon catheter having an elongated element around the balloon has been proposed. For example, in the balloon catheter shown in Patent Document 3, elongated elements are provided on the outer peripheral side of the balloon so as to straddle the balloon in the longitudinal direction. When the balloon is inflated, the elongated element meshes with the lesion due to the inflation of the balloon, and an axial channel is formed in the lesion by the elongated element. Here, although the structure which fixes an elongate element over the whole longitudinal direction with respect to the expansion | swelling area | region of a balloon is also considered, the softness | flexibility of a balloon will be impaired in this case. On the other hand, by providing the elongate element so as to straddle the inflating region of the balloon as described above, the effect of providing the elongate element can be exhibited while preventing the flexibility of the balloon as much as possible. .
JP 2002-253678 A JP-A-11-33122 JP 2005-517474 A

  However, the elongate element is provided outside the balloon, and the elongate element directly touches the inner wall of the blood vessel in the living body when PTCA is treated. Then, although the above-described advantages can be obtained by providing the elongated elements, there may be some inconveniences.

  As the inconvenience, for example, it is conceivable that the elongated element is caught on the inner wall of the blood vessel or the like when the balloon catheter is inserted into or removed from the living body. Further, for example, it is conceivable that the elongated element comes off when the balloon is inflated. Thus, there is still room for improvement in balloon catheters with elongated elements.

  The present invention has been made in view of the above circumstances, and provides a balloon catheter having a slender element around the balloon, and a balloon catheter capable of improving the configuration relating to the attachment of the slender element. This is the main purpose.

  Hereinafter, means and the like effective for solving the above-described problems will be described while showing functions and effects as necessary. In the following, in order to facilitate understanding, a corresponding configuration example in the embodiment of the invention is appropriately shown in parentheses, etc., but is not limited to the specific configuration shown in parentheses.

Means 1. A catheter tube (catheter tube 11 etc.);
A hollow balloon (balloon 13 or the like) that is provided on the distal end side of the catheter tube so as to cover the catheter tube from the outside and expands or contracts when fluid flows through the fluid lumen of the catheter tube;
The balloon is provided so as to straddle at least the inflation region in the longitudinal direction, the proximal end is fixed to the proximal side of the inflation region, and the distal end is distal to the inflation region. An elongated element (such as a linear member 31) that displaces outward in the radial direction of the balloon following the inflation of the balloon;
With
One of the fixing points on the proximal end side or the distal end side of the elongated element has a strength against the tensile force when a tensile force is applied to the elongated element. A balloon catheter characterized in that the balloon catheter is set lower than the other of the fixed portions on the side and the elongated element itself.

  In the configuration in which the elongated element is provided so as to straddle at least the inflated region of the balloon in the longitudinal direction on the outer peripheral side of the balloon, the elongated element has a certain strength so as not to be broken when the balloon is inflated. Need to be. On the other hand, in the configuration in which the elongate element is provided as described above, there is a concern that the elongate element may be caught by a lesion portion that forms a stenosis site in a living body, an indwelling stent, or the like. In this case, since the elongated element has a certain strength as described above, there is a possibility that the extraction operation cannot be performed satisfactorily even if the balloon catheter is extracted from the living body. On the other hand, according to the means 1, one of the fixing points on the proximal end side or the distal end side of the elongated element has a strength against the tensile force when a tensile force is applied to the elongated element. However, since it is set lower than the other of the fixing points on the proximal end side or the distal end side and the elongated element itself, when the balloon catheter is extracted from the living body, the fixing on the side where the strength is low The elongated element is detached at the location, and the hooked state can be released. Even in this case, the other of the fixing points is set to have a higher strength against the tensile force than the above-mentioned one, so that only one of them is separated and the elongated element is released from the catheter tube side. This is suppressed.

Mean 2. A catheter tube (catheter tube 11 etc.);
A hollow balloon (such as a balloon 13) that is provided on the distal end side of the catheter tube so as to cover the catheter tube from the outside and expands or contracts when fluid flows through the fluid lumen of the catheter tube;
The balloon is provided so as to straddle at least the inflation region in the longitudinal direction, the proximal end is fixed to the proximal side of the inflation region, and the distal end is distal to the inflation region. An elongated element (such as a linear member 31) that displaces outward in the radial direction of the balloon following the inflation of the balloon;
With
The fixing point on the distal end side of the elongated element has a strength against the tensile force when a tensile force is applied to the elongated element, and the fixing point on the proximal end side of the elongated element and the elongated element A balloon catheter characterized by being set lower than itself.

  According to the means 2, in addition to the effects described in the means 1, the following excellent effects can be obtained. In other words, when a tensile force is applied to the elongated element, the strength against the tensile force is such that the fixed position on the distal end side of the elongated element is lower than the fixed position on the proximal end side and the elongated element itself. Therefore, when the balloon catheter is pulled out from the living body in the hooked state, the elongated element is detached at the distal end side. Then, when the elongated element is disengaged on the distal end side, the free end of the elongated element is positioned on the distal side in the extraction direction of the balloon catheter.

  For example, in the configuration in which the elongated element is detached on the proximal end side, the free end of the elongated element is located on the distal end side in the extraction direction. In order to release the hooked state of the elongated element, the free end of the elongated element needs to pass through the hooked position, and the free end passes through the hooked position in a situation where the free end is located on the proximal end side. In order to do so, it is necessary to push the balloon catheter in the insertion direction and to pull out the balloon catheter after the free end has passed through the hooked portion. Further, if the balloon catheter is to be pulled out without being pushed in the insertion direction, the free end needs to be turned to the distal side in the pulling direction so as to pass through the hooked portion, and the hooked state may not be released satisfactorily. . On the other hand, according to the configuration of the present means, the free end is positioned on the distal side in the extraction direction as described above, so that the hooked state can be satisfactorily released, and the balloon catheter is extracted accordingly. Work can be performed well.

  Note that the “elongated element” in the means 1 or 2 may have a function as a non-slip for engaging with a lesion when the balloon is inflated to prevent the balloon from slipping. It may have a function as a cutting blade for opening a lesion when it is inflated, or may have a function of forming a bite channel in the lesion. It may have a function as a contrast body for confirming the position in the body outside the living body.

  The catheter tube does not need to be a single tube, and includes an outer tube and an inner tube that is inserted into the inner tube and extended to the distal end side of the outer tube. It may be. In this case, the balloon is fixed at its proximal end to the distal end of the outer tube and the distal end is fixed to the extension region of the inner tube so that fluid flow to the balloon is through the lumen of the outer tube. It is recommended that

  Means 3. The elongated element is fixed to an object to be fixed using an adhesive at least on the side where the strength against the tensile force is set low at each of the fixing points of the elongated element. Or the balloon catheter of 2.

  According to the means 3, it is possible to easily set the strength against the tensile force by selecting the type of adhesive or setting the application area.

Means 4. An adhesive layer (adhesive layer 46) made of the adhesive is provided between the elongated element and the object to be fixed on the side where the strength against the tensile force is set low in each fixing portion of the elongated element. Formed,
Means 3, wherein when a predetermined tensile force is applied, cohesive failure or interface failure of the adhesive layer occurs before the elongated element and the substrate to be fixed are destroyed. Balloon catheter.

  According to the means 4, when the elongated element is caught in the living body, the elongated element is detached without requiring the destruction of the elongated element itself or the fixing target itself of the elongated element. Therefore, the hooked state can be released without difficulty.

  Means 5. An elastic body (distal fixation) that is provided on the side where the strength against the tensile force is set low in each fixing portion of the elongated element and elastically deforms in accordance with the displacement of the elongated element when the balloon is inflated. The balloon catheter according to any one of the means 1 to 4, further comprising a tube 41 for use.

  According to the means 5, when the balloon is inflated, the elastic body is elastically deformed in accordance with the displacement of the elongated element, and a part of the load applied to the elongated element during the displacement is received by the elastic body. In addition, since the elastic body is provided on the side where the strength against the tensile force in each fixed portion of the elongated element is set low, in the configuration that can be satisfactorily released from the hooked state in the living body When the balloon is inflated, a part of the load at that time can be received by the elastic body, and it is possible to prevent the elongated element from being detached at the time of the inflation.

  Means 6. Of the fixed portions of the elongate element, provided on the side where the strength against the tensile force is set to be low, it has an endless or endless annular shape, and further part of the outer peripheral surface in the longitudinal direction of the catheter tube The first ring portion (first fixed ring portion 42 and the like) fixed so as to surround the outer periphery of the tube and the end of the elongated element are fixed in a state of covering from the outside, and the elongated element is displaced when the balloon is inflated. Means 1 to 2 further comprising an elastic body (distal fixation tube 41 and the like) integrally formed with a second ring portion (second fixing ring portion 43 and the like) which is elastically deformed in accordance with 4. The balloon catheter according to any one of 4 above.

  According to the means 6, when the balloon is inflated, the elastic body is elastically deformed in accordance with the displacement of the elongated element, and a part of the load applied to the elongated element during the displacement is received by the elastic body. In particular, the elastic body has an endless or endless annular shape, and is fixed so as to surround a part of the outer peripheral surface in the longitudinal direction of the catheter tube in the circumferential direction. Thereby, the elastic body can be firmly fixed to the catheter tube. Further, since the elastic body is fixed in a state where the end of the elongated element is covered from the outside, it is possible to reliably receive a part of the load at the time when the balloon is inflated. In addition, since the elastic body is provided on the side where the strength against the tensile force in each fixed portion of the elongated element is set low, in the configuration that can be satisfactorily released from the hooked state in the living body When the balloon is inflated, a part of the load at that time can be received by the elastic body, and it is possible to prevent the elongated element from being detached at the time of the inflation. That is, according to this configuration, it is possible to satisfy both conflicting demands of suppressing the detachment of the elongated element during the inflation of the balloon and improving the release of the hooked state.

  Mean 7 The second annular portion has an inner circumferential surface spaced outward from the outer circumferential surface of the catheter tube, and an end of the elongated element is fixed to the inner circumferential surface of the second annular portion. The balloon catheter according to means 6 described above.

  According to the means 7, since the inner peripheral surface of the second ring portion is spaced outward from the outer peripheral surface of the catheter tube, the elastic deformation is favorably performed. And since the edge part of an elongate element is being fixed with respect to the internal peripheral surface of the said 2nd ring part, a part of load when an elongate element is displaced at the time of expansion | swelling of a balloon is due to elastic deformation of a 2nd ring part. It is possible to prevent the elongated element from being detached during the expansion.

  Furthermore, the outer peripheral surface of the balloon catheter is defined by the outer peripheral surface of the annular elastic body at the fixing portion of the end portion of the elongated element. Compared to the configuration in which the elongated element is fixed to the outer peripheral surface of the elastic body, It is possible to make the outer peripheral surface of the fixed portion less uneven. Therefore, it is possible to improve the passability when the balloon catheter is inserted into the living body.

  In addition, by fixing the elongated element to the inner peripheral surface of the second ring portion using an adhesive, it is possible to suppress the separation of the elongated element when the balloon is inflated and to improve the release of the hooked state. It becomes possible to implement | achieve suitably.

Means 8. Of each of the fixing points of the elongated element, the side set with a low strength against the tensile force is the distal end side,
The first ring part and the second ring part are continuously formed so as to be located on the same axis,
Further, the elastic body is arranged such that the first ring portion is located on the distal end side, and a space between the inner peripheral surface of the second ring portion and the outer peripheral surface of the catheter tube is close. It is open toward the top end side,
The distal end portion of the elongated element is inserted between the second ring portion and the catheter tube from the opened side, and is fixed to the inner peripheral surface of the second ring portion. The balloon catheter according to means 7.

  According to the means 8, in the configuration that has the function and effect described in the means 7, the outer peripheral surface of the balloon catheter has a smooth shape with less irregularities when viewed from the distal end side of the balloon catheter. Therefore, it is possible to improve the passability when the balloon catheter is inserted into the living body.

  Means 9. Any one of means 6 to 8, wherein a plurality of the elongate elements are provided, and the end portions on the elastic body side of the elongate elements are all fixed to the second ring portion of the elastic body. The balloon catheter described.

  According to the means 9, in the configuration in which a plurality of elongated elements are provided, the above-described excellent effect can be obtained for all the elongated elements. Further, the number of members constituting the balloon catheter can be reduced as compared with a configuration in which an elastic body is individually provided for each elongated element.

  Means 10. The balloon catheter according to any one of means 4 to 9, wherein the elastic body is formed so as to be more flexible than the catheter tube and the elongated element.

  According to the means 10, the effects described in the means 5 and the means 6 are preferably exhibited.

Means 11. A catheter tube (catheter tube 11 etc.);
A hollow balloon (balloon 13 or the like) that is provided on the distal end side of the catheter tube so as to cover the catheter tube from the outside and expands or contracts when fluid flows through the fluid lumen of the catheter tube;
The balloon is provided so as to straddle at least the inflation region in the longitudinal direction, the proximal end is fixed to the proximal side of the inflation region, and the distal end is distal to the inflation region. An elongated element (such as a linear member 31) that displaces outward in the radial direction of the balloon following the inflation of the balloon;
With
2. The balloon catheter according to claim 1, wherein the elongate element has a region where the breaking strength of the elongate element itself is set lower than that at the proximal end side from the center, at the distal end side from the center in the longitudinal direction.

  In the configuration in which an elongated element is provided on the outer peripheral side of the balloon so as to straddle at least the inflated region of the balloon in the longitudinal direction, a lesion part where the elongated element forms a stenosis site in a living body, a stent that is indwelling, etc. There is a concern that it will be caught in On the other hand, according to the means 11, the elongate element has a region where the breaking strength of the elongate element itself is set lower than the center in the distal end side than the center in the longitudinal direction. Therefore, when an attempt is made to remove the balloon catheter from the living body, the elongated element breaks in a region where the breaking strength is set low, and the hooked state can be released.

  In addition, when the elongated element itself is broken, the broken portion is located on the distal end side from the center, and each divided piece of the elongated element divided by breaking is located on the distal end side rather than the proximal end side. Shorter. Of the segment pieces of the elongated element, the free end of the segment piece on the proximal end side is located on the distal side in the extraction direction of the balloon catheter with respect to the fixed end, and the free end of the segment piece on the distal end side is the fixed end In contrast, it is located on the distal end side in the extraction direction of the balloon catheter. In this case, when the balloon catheter is withdrawn, the distal end side divided piece is in the middle of the removal path, the other lesioned part, the bent part, and the stent already placed in place, compared with the proximal end side divided piece. It is thought that it is easy to get caught in etc. On the other hand, each of the elongated elements divided by breaking as described above is made shorter at the distal end side than at the proximal end side, so that the divided pieces at the time of removing the balloon catheter can be obtained. Is less likely to occur.

  Means 12. The elongated element is formed of the same material throughout the longitudinal direction, and the region where the breaking strength is set lower is the cross-sectional area of the cross section perpendicular to the longitudinal direction than the proximal end side than the center. The balloon catheter according to the means 11, wherein the balloon catheter is a region formed so as to be small.

  According to the means 12, the effect of the means 11 can be obtained with a relatively simple configuration in which the cross-sectional area of the cross section of the elongated element is adjusted.

  Means 13. The balloon catheter according to means 12, wherein the region where the breaking strength is set low is a region including a fixing portion on the distal end side of the elongated element.

  According to the means 13, when the elongated element itself is broken, the length of the split piece on the distal end side can be shortened as much as possible, and the split piece may be caught when the balloon catheter is pulled out. It is further reduced.

  The following means can be considered in place of the above means 1 to 13.

Means 14. A catheter tube (catheter tube 11 etc.);
A hollow balloon (balloon 13 or the like) that is provided on the distal end side of the catheter tube so as to cover the catheter tube from the outside and expands or contracts when fluid flows through the fluid lumen of the catheter tube;
The balloon is provided so as to straddle at least the inflation region in the longitudinal direction, the proximal end is fixed to the proximal side of the inflation region, and the distal end is distal to the inflation region. An elongated element (such as a linear member 31) that displaces outward in the radial direction of the balloon following the inflation of the balloon;
The elongated element is provided at at least one of the proximal end and the distal end, has an endless or endless annular shape, and further surrounds a circumferential surface of a part of the longitudinal direction of the catheter tube in the circumferential direction. The fixed first ring portion (first fixed ring portion 42 and the like) and the end of the elongated element are fixed in a state of covering from the outside, and elastically deformed in accordance with the displacement of the elongated element when the balloon is inflated. An elastic body (distal fixation tube 41 and the like) integrally formed with the second ring portion (second fixation ring portion 43 and the like);
A balloon catheter comprising:

  According to the means 14, the elastic body has an endless or endless annular shape and is fixed so as to surround a part of the outer peripheral surface in the longitudinal direction of the catheter tube in the circumferential direction. It becomes possible to fix to. In addition, since the elastic body is fixed in a state in which the end of the elongated element is covered from the outside, it is possible to reliably receive a part of the load at the time when the balloon is inflated. It is possible to prevent the elongated element from coming off.

  Means 15. The second annular portion has an inner circumferential surface spaced outward from the outer circumferential surface of the catheter tube, and an end of the elongated element is fixed to the inner circumferential surface of the second annular portion. The balloon catheter according to means 14 described above.

  According to the means 15, since the inner peripheral surface of the second ring portion is spaced outward from the outer peripheral surface of the catheter tube, the elastic deformation is favorably performed. And since the edge part of an elongate element is being fixed with respect to the internal peripheral surface of the said 2nd ring part, a part of load when an elongate element is displaced at the time of expansion | swelling of a balloon is due to elastic deformation of a 2nd ring part. It is possible to prevent the elongated element from being detached during the expansion.

  Furthermore, the outer peripheral surface of the balloon catheter is defined by the outer peripheral surface of the annular elastic body at the fixing portion of the end portion of the elongated element. Compared to the configuration in which the elongated element is fixed to the outer peripheral surface of the elastic body, It is possible to make the outer peripheral surface of the fixed portion less uneven. Therefore, it is possible to improve the passability when the balloon catheter is inserted into the living body.

Means 16. The elastic body is provided with respect to the distal end of the elongated element (such as the distal end 33),
The first ring part and the second ring part are continuously formed so as to be located on the same axis,
Further, the elastic body is arranged such that the first ring portion is located on the distal end side, and a space between the inner peripheral surface of the second ring portion and the outer peripheral surface of the catheter tube is close. It is open toward the top end side,
The distal end portion of the elongated element is inserted between the second ring portion and the catheter tube from the opened side, and is fixed to the inner peripheral surface of the second ring portion. The balloon catheter according to means 15.

  According to the means 16, the outer peripheral surface of the balloon catheter is formed into a smooth shape with less irregularities when viewed from the distal end side of the balloon catheter in the configuration that achieves the operational effects described in the means 15. Therefore, it is possible to improve the passability when the balloon catheter is inserted into the living body.

  Means 17. Any one of means 14 to 16, wherein a plurality of the elongated elements are provided, and the end portions on the elastic body side of the elongated elements are all fixed to the second ring portion of the elastic body. The balloon catheter described.

  According to the means 17, in the configuration in which a plurality of elongated elements are provided, the above-described excellent effect can be obtained for all the elongated elements. Further, the number of members constituting the balloon catheter can be reduced as compared with a configuration in which an elastic body is individually provided for each elongated element.

  Means 18. The balloon catheter according to any one of means 14 to 17, wherein the elastic body is formed so as to be more flexible than the catheter tube and the elongated element.

  According to the means 18, the effects described in the means 14 and the like are suitably exhibited.

(First embodiment)
Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic overall side view of a balloon catheter 10.

  As shown in FIG. 1, a balloon catheter 10 includes a catheter tube (catheter shaft) 11, a hub 12 attached to a proximal end (base end) of the catheter tube 11, and a distal end of the catheter tube 11. And a balloon 13 attached to the portion (tip portion).

  The catheter tube 11 is composed of a plurality of tubes (tubular shafts) and has an inner / outer multiple tube structure (inner / outer double tube structure) from at least a midway position in the longitudinal direction (axial direction) to the position of the balloon 13. Specifically, the catheter tube 11 includes an outer tube (outer tube) 15 and an inner tube (inner tube) 16 having an inner diameter and an outer diameter smaller than those of the outer tube 15. The inner and outer multiple tube structures are formed by inserting 16.

  Incidentally, both the outer tube 15 and the inner tube 16 are made of polyamide resin so as to have a predetermined flexibility. However, as long as it has flexibility, it is not limited to polyamide resin, and synthetic resin materials such as polyethylene resin, polypropylene resin, polyurethane resin, and polyimide resin can be used. An additive may be mixed with the base material using the synthetic resin materials described above. Further, the outer tube 15 and the inner tube 16 may be formed using different synthetic resin materials.

  The inner tube 16 is provided to extend to the distal end side from the outer tube 15, and the balloon 13 is provided for the extended region of the inner tube 16 and the distal end portion of the outer tube 15. .

  Next, the configuration of the balloon 13 and its surroundings will be described in detail with reference to FIGS. FIG. 2A is a schematic side view of the configuration of the balloon 13 in the deflated state and its periphery, and FIG. 2B is a cross-sectional view of FIG. FIG. 3A is a schematic side view of the inflated balloon 13 and its surrounding structure, and FIG. 3B is a cross-sectional view of FIG. 4A is a longitudinal sectional view of FIG. 3A, FIG. 4B is an enlarged view of a region C1 in FIG. 4A, and FIG. 4C is a region C2 in FIG. 4A. FIG.

  The balloon 13 is made of a polyamide resin. However, as long as it has flexibility, it is not limited to polyamide resin, and polyethylene resin, polypropylene resin, polyurethane resin, polyimide resin, silicon rubber, natural rubber, etc. may be used. it can.

  As shown in FIG. 4 and the like, the balloon 13 has a proximal end joined to the outer tube 15 and a distal end joined to the inner tube 16. The outer peripheral surface of the inner tube 16 is covered from the outside. In this case, the lumen 15a of the outer tube 15 constitutes a fluid lumen for guiding the compressed fluid supplied through the hub 12 into the balloon 13, and the lumen 16a of the inner tube 16 constitutes a guide wire lumen. Yes. Note that the bonding of the balloon 13 to the outer tube 15 and the inner tube 16 is performed by heat welding, but the present invention is not limited to this and may be performed using an adhesive or the like.

  The balloon 13 is formed so that the inner diameter and the outer diameter are changed in a plurality of stages in the inflated state. That is, as shown in FIGS. 3 and 4, the balloon 13 has a proximal end side leg region (proximal end side joining region) 21 joined to the outer tube 15 and an inner diameter and an outer side toward the distal end side. The proximal end side cone region (proximal end side inclined region or proximal end side tapered region) 22 is tapered so that the diameter is increased, and the inner diameter and the outer diameter are the same throughout the longitudinal direction. The straight tube region 23 that forms the maximum outer diameter region of the balloon 13 and the distal end side cone region that is tapered so that the inner diameter and the outer diameter are reduced toward the distal end side. Region or distal end tapered region) 24 and a distal end leg region (distal end joining region) 25 joined to the inner tube 16 in this order from the proximal end side.

  The balloon 13 is formed in a plurality of wings (specifically, three wings), and in the contracted state, a plurality of wings (flaps or wings) 26 are formed as shown in FIG. As described above, the expansion region composed of the proximal end cone region 22, the straight tube region 23, and the distal end cone region 24 is folded. Then, each of the wings 26 is wound around the inner tube 16. More specifically, when the balloon 13 is changed from the inflated state to the deflated state, the inflated region of the balloon 13 is folded so that a plurality of wings 26 standing perpendicular to the longitudinal direction are formed at equal intervals. Each wing 26 is wound around the inner tube 16.

  Here, the present balloon catheter 10 includes a linear member (linear element or elongated element) 31 outside the balloon 13. Therefore, the linear member 31 will be described in detail below.

  The linear member 31 is formed in the form of a wire or a monofilament so as to have suitable rigidity and flexibility. Specifically, the material forming the linear member 31 is formed of a polyamide-based resin. In addition, if it has suitable rigidity and flexibility, it will not be limited to a polyamide-type resin, Another synthetic resin can be used. Moreover, it is not limited to a synthetic resin, You may use stainless steel, a Ni-Ti alloy, or a carbon fiber.

  The length of the linear member 31 is larger than the length of the balloon 13 in the longitudinal direction, and as shown in FIG. 4, the linear member 31 straddles at least the inflation region of the balloon 13 in the longitudinal direction on the outer peripheral side of the balloon 13. Thus, only the both ends are fixed. In this case, the proximal end portion 32 of the linear member 31 is fixed to a proximal side fixing tube 37 provided closer to the proximal end side of the outer tube 15 than the proximal end side leg region 21 of the balloon 13. By being present, it is held by the outer tube 15. Further, the distal end portion 33 of the linear member 31 is fixed to a distal side fixing tube 41 provided on the distal end side of the inner tube 16 relative to the distal end side leg region 25 of the balloon 13. Thus, the inner tube 16 is held. Between the proximal end portion 32 and the distal end portion 33, the linear member 31 straddles the entire region of the balloon 13 in the longitudinal direction.

  Here, the linear member 31 is fixed only at the proximal end portion 32 and the distal end portion 33, and is not fixed at all to the balloon 13. Thereby, compared with the structure which fixes the linear member 31 with respect to the expansion | swelling area | region of the balloon 13 over the whole longitudinal direction, it can provide the linear member 31 so that the softness | flexibility of the balloon 13 may not be impaired as much as possible. it can. Further, a configuration in which at least one of both ends of the linear member 31 is fixed to the leg regions 21 and 25 of the balloon 13 is also conceivable. In this case, in the leg regions 21 and 25, a region and a linear shape for fixing the balloon 13 are considered. There is a possibility that the region for fixing the member 31 overlaps and the balloon catheter 10 becomes locally hard in the overlapped region. If it does so, we are anxious about the kink resistance of the balloon catheter 10 falling. On the other hand, the linear member 31 is provided while preventing the kink resistance from being lowered as much as possible by shifting the region for fixing the linear member 31 with respect to the leg regions 21 and 25 as described above. Can do.

  A plurality of linear members 31 are provided, and these linear members 31 are arranged at equal intervals in the circumferential direction on the outer peripheral side of the balloon 13. Specifically, three linear members 31 are provided in one-to-one correspondence with the wings 26 of the balloon 13, and each linear member 31 is arranged at 120 ° intervals in the circumferential direction on the outer peripheral side of the balloon 13. ing. In the deflated state of the balloon 13, as shown in FIG. 2B, each linear member 31 is positioned on the root side of the corresponding wing 26, and the wings 26 are folded, so that each linear shape A portion of the member 31 that overlaps each wing 26 is covered from the outside by the corresponding wing 26. In the inflated state of the balloon 13, as shown in FIG. 3 (b), each linear member 31 follows the inflating of the balloon 13 and the portion overlapping the wings 26 is displaced outward in the radial direction. It becomes. In this case, the intermediate portion of each linear member 31 is located on the outer peripheral surface of the balloon 13. Each linear member 31 is formed in a triangular shape in cross section, and when the balloon 13 is in an inflated state, one side of the triangular shape of each linear member 31 is located on the outer peripheral surface of the balloon 13, and the triangular shape One corner protrudes outward from the outer peripheral surface of the balloon 13. Each linear member 31 does not necessarily have a triangular shape in the cross section, and may have a circular shape in the cross section as long as the function of preventing slipping when the balloon 13 is inflated to be described later is fulfilled. The surface may be rectangular.

  Next, a characteristic configuration related to the fixing of the linear member 31 will be described. In addition, since the structure regarding fixation in each linear member 31 is all the same, in the following description, the one linear member 31 is demonstrated fundamentally.

  The proximal end portion 32 of the linear member 31 is fixed to the proximal side fixing tube 37 as described above.

  The proximal side fixing tube 37 is formed of a thermoplastic elastomer as a base material so as to have higher flexibility than the outer tube 15 and the linear member 31. Specifically, it is formed using a polyamide-based elastomer as a base material. However, as long as it has higher flexibility than the outer tube 15 and the linear member 31, it is not limited to a polyamide-based elastomer, and a thermoplastic such as a butadiene-based, urethane-based, or silicone-based polymer or copolymer. An elastomer can be used. The proximal fixing tube 37 is formed in an endless annular shape, and has the same outer diameter and inner diameter throughout the axial direction. The inner diameter of the proximal fixing tube 37 is the same as the outer diameter of the outer tube 15.

  The proximal end portion 32 of the linear member 31 is thermally welded to the proximal side fixing tube 37. In this case, the linear member 31 is formed using a polyamide-based resin as a base material, and the proximal-side fixing tube 37 is formed of a polyamide-based elastomer. Further, the heat welding is performed on the linear member 31 and the proximal side. Since both the fixing tubes 37 are melted, no boundary is formed between the proximal end portion 32 of the linear member 31 and the proximal fixing tube 37 after the thermal welding. Thereby, the linear member 31 and the proximal side fixing tube 37 are firmly fixed. The fixing may be performed using an adhesive as long as the fixing strength is higher than the fixing portion of the distal end portion 33 described later.

  The proximal-side fixing tube 37 in which the linear member 31 is integrated is fixed to the outer peripheral surface of the outer tube 15. This fixing is performed using an adhesive, and an adhesive layer 35 is interposed between the proximal side fixing tube 37 and the outer peripheral surface of the outer tube 15 as shown in FIG. ing. In this case, adhesion between the proximal side fixing tube 37 and the outer tube 15 is performed by a cyanoacrylate adhesive. However, the type of the adhesive is arbitrary as long as both can be firmly fixed, and an ultraviolet curable acrylic resin adhesive may be used. In addition, urethane resin-based adhesives, ethylene-vinyl acetate resin-based adhesives, epoxy resin-based adhesives, silicone-based adhesives, etc. may be used. These adhesives are reactive, solution-based, and water-dispersed. Either a system or a solid system may be used.

  Further, the adhesive strength is arbitrary as long as it is firmly fixed, but cohesive failure in which the adhesive layer 35 breaks when performing a tensile inspection by tension, or the adhesive layer 35 and the linear member 31. Alternatively, it is preferable that the destruction of the base material that destroys either the proximal-side fixing tube 37 or the outer tube 15 occurs without causing the interface destruction that breaks the interface with the outer tube 15. However, cohesive failure or interface failure may occur as long as the adhesive strength is higher than the fixing portion of the distal end portion 33 described later. Further, if the fixing strength is higher than the fixing portion of the distal end portion 33 described later, the proximal side fixing tube 37 and the outer tube 15 may be fixed by at least one heat welding. Good.

  The distal end 33 of the linear member 31 is fixed to the distal side fixing tube 41 as described above. Here, the distal side fixing tube 41 will be described.

  The distal side fixing tube 41 is formed using a thermoplastic elastomer as a base material so as to have higher flexibility than the inner tube 16 and the linear member 31. Specifically, it is formed using a polyamide-based elastomer as a base material. However, as long as it has higher flexibility than the inner tube 16 and the linear member 31, it is not limited to polyamide elastomer, and thermoplastics such as butadiene, urethane, and silicone polymers and copolymers. An elastomer can be used.

  The distal side fixing tube 41 is formed in an endless annular shape, and is positioned on the same axis with respect to the first fixing ring portion 42 fixed to the inner tube 16 and the first fixing ring portion 42. A second fixed ring portion 43 that is provided continuously and to which the linear member 31 is fixed. The first fixed ring portion 42 is formed so as to have the same inner diameter over the entire axial direction, and the outer peripheral surface is tapered so as to taper toward the distal end portion. On the other hand, the second fixed ring portion 43 is formed by expanding the inner diameter and the outer diameter with respect to the first fixed ring portion 42. Specifically, the second fixed ring portion 43 is a tapered stepped portion 44 that is continuous from the first fixed ring portion 42, and the same diameter portion 45 that is continuous from the stepped portion 44 and has the same inner diameter and outer diameter. And. The stepped portion 44 is not limited to a tapered shape as long as it has a function of expanding the diameter from the first fixed ring portion 42.

  The distal side fixing tube 41 is disposed on the outer peripheral surface of the inner tube 16 from the distal end portion of the inner tube 16 so that the second fixing ring portion 43 is on the proximal end side of the balloon catheter 10. The first fixed ring portion 42 is fixed to the outer peripheral surface of the inner tube 16. In this case, using the fact that the inner tube 16 is formed using a polyamide-based resin as a base material and the distal-side fixing tube 41 is formed using a polyamide-based elastomer as a base material, the inner tube 16 is fixed by thermal welding of both. Has been done. Since the fixing is performed by heat welding as described above, the step of the first fixing ring portion 42 with respect to the distal end portion of the inner tube 16 is reduced.

  The fixing between the first fixing ring portion 42 and the inner tube 16 is not limited to the heat welding, and the fixing may be performed using the adhesive as exemplified above. Further, the entire inner peripheral surface of the first fixed ring portion 42 is fixed to the outer peripheral surface of the inner tube 16.

  As described above, since the second fixed ring portion 43 has the stepped portion 44 for expanding the diameter with respect to the first fixed ring portion 42, as shown in FIG. The inner peripheral surface is separated from the outer peripheral surface of the inner tube 16 by a distance X. In this case, since the distal side fixing tube 41 is formed of a thermoplastic elastomer as described above, the same-diameter portion 45 has an essentially elastically deformable function. Since the inner peripheral surface of the diameter portion 45 is separated from the outer peripheral surface of the inner tube 16, the elastic deformation of the same diameter portion 45 is allowed.

  Since the distal fixation tube 41 is arranged such that the second fixation ring portion 43 is on the proximal end side of the balloon catheter 10, the opening of the same diameter portion 45 is opened toward the proximal end side. ing. Through this opening, the distal end portion 33 of the linear member 31 is inserted into the space between the same diameter portion 45 and the inner tube 16, and the distal end portion 33 is formed on the inner peripheral surface of the same diameter portion 45. It is fixed. The fixing of the distal end portion 33 to the inner peripheral surface of the same diameter portion 45 is performed for all the linear members 31.

  The distal end portion 33 and the same diameter portion 45 of the linear member 31 are fixed by using an adhesive, and a gap between the distal end portion 33 and the inner peripheral surface of the same diameter portion 45 is illustrated in FIG. As shown in 4 (c), an adhesive layer 46 is interposed. In this case, the adhesion between the distal end portion 33 and the same diameter portion 45 is performed when the linear member 31 is proximal to the linear member 31 when a predetermined tensile force larger than that when the balloon 13 is inflated is applied to the linear member 31. The adhesive strength is set so that the linear member 31 is detached from the same diameter portion 45 at a stage before the end portion 32 is detached from the outer tube 15 and the linear member 31 itself is broken.

  Specifically, the adhesion between the distal end portion 33 and the same diameter portion 45 of the linear member 31 is performed by a cyanoacrylate adhesive, and the adhesive is bonded when a tensile inspection is performed by tension. A material having a degree of cohesive failure that destroys the agent layer 46 or an interface failure that destroys the interface of the adhesive layer 46 is used.

  Here, 15 test pieces are respectively prepared from the proximal end side and the distal end side among the fixed portions of the linear member 31 in the balloon catheter 10, and Shimadzu Autograph AGS-H (Co., Ltd.) is used as a measuring instrument. Tensile tests were performed using Shimadzu Corporation. Moreover, in the said tension test, it tested until the linear member 31 removed | separated with the tension | pulling speed of 200 mm / min, and measured the maximum intensity | strength in that case as a breaking strength. As a result, the proximal end side had a maximum breaking strength of 7.1 N, a minimum breaking strength of 4.0 N, and an average breaking strength of 6.0 N. On the other hand, on the distal end side, the maximum breaking strength was 2.6 N, the minimum breaking strength was 1.6 N, and the average breaking strength was 2.0 N.

  Note that the type of adhesive is arbitrary as long as the distal end portion 33 and the same diameter portion 45 of the linear member 31 can be fixed as described above, and an ultraviolet curable acrylic resin adhesive. May be used. In addition, urethane resin-based adhesives, ethylene-vinyl acetate resin-based adhesives, epoxy resin-based adhesives, silicone-based adhesives, etc. may be used. These adhesives are reactive, solution-based, and water-dispersed. Either a system or a solid system may be used. Even in this case, the type of adhesive and the area where the adhesive is applied (for example, the length in the longitudinal direction of the adhesive layer) are set so that the breaking strength at the distal end is in the above range. By selecting, when a predetermined tensile force larger than that when the balloon 13 is inflated is applied to the linear member 31, the proximal end portion 32 of the linear member 31 is detached from the outer tube 15 and is linear. The linear member 31 can be detached from the same diameter portion 45 at a stage before the destruction of the member 31 itself.

  Next, the manufacturing process of the balloon catheter 10 will be briefly described.

  As a preparation process, each component is manufactured. In this preparation step, the three linear members 31 are fixed to the proximal side fixing tube 37. As described above, the linear members 31 are integrated with the proximal-side fixing tube 37 in advance, so that the linear members 31 are arranged at intervals of 120 °.

  Thereafter, the inner tube 16 is inserted into the outer tube 15, and the balloon 13 is fixed to each of the outer tube 15 and the inner tube 16. Note that, at a timing before the balloon 13 is arranged, the proximal side fixing tube 37 in which the three linear members 31 are integrated is arranged on the outer peripheral surface side of the outer tube 15. However, at this timing, the proximal side fixing tube 37 is not fixed to the outer tube 15.

  Subsequently, the distal side fixing tube 41 is fixed to the inner tube 16. In this case, the first welding ring portion 42 of the distal side fixing tube 41 and the inner tube 16 are thermally welded after the distal side fixing tube 41 is disposed on the outer peripheral surface of the inner tube 16. This is performed by pressing a heat welder against the outer peripheral surface side of the fixed ring portion 42. At this time, in order to prevent the inner diameter of the inner tube 16 from being crushed, the inner diameter of the inner tube 16 is within the inner tube 16. And a hot welding jig having substantially the same outer diameter.

  Thereafter, the distal end portion 33 of each linear member 31 is fixed to the inner peripheral surface of the second fixing ring portion 43 in the distal side fixing tube 41. Subsequently, the balloon-side catheter 10 is manufactured by fixing the proximal-side fixing tube 37 to the outer tube 15. The hub 12 is fixed at an arbitrary timing.

  Next, a method for using the balloon catheter 10 will be described with reference to FIG.

  First, a guiding catheter is inserted into a sheath introducer inserted into a blood vessel, and is introduced to the coronary artery entrance by pushing and pulling. Next, the guide wire is inserted into the guide wire lumen of the balloon catheter 10 and introduced from the coronary artery entrance to the peripheral site through the stenosis. Subsequently, the balloon catheter 10 is inserted along the guide wire to the stenosis site while performing a push-pull operation. Thereby, as shown to Fig.5 (a), the balloon 13 of a contracted state will be located in a constriction location.

  In this case, as described above, the first fixing ring portion 42 constituting the distal end side of the distal side fixing tube 41 is fixed to the inner tube 16 by heat welding, and is fixed using an adhesive or the like. The level | step difference in the said 1st fixed ring part 42 is small compared with the structure to be performed. Further, the distal end portion 33 of the linear member 31 is fixed to the inner peripheral surface of the same-diameter portion 45 of the distal-side fixing tube 41 and is accommodated in the same-diameter portion 45. That is, as compared with the configuration in which the distal end portion 33 of the linear member 31 is fixed to the outer peripheral surface of the same diameter portion 45, local protrusions are not generated when viewed in the circumferential direction of the balloon catheter 10. Furthermore, when viewed from the distal end side of the balloon catheter 10, the outer peripheral surface of the balloon catheter 10 has a smooth shape with few irregularities. Therefore, the passage of the balloon catheter 10 is improved.

  Thereafter, the balloon 13 is inflated by injecting a compressed fluid into the balloon 13 from the hub 12 side using a pressurizer. At the time of inflation, the linear member 31 projects outwardly following the inflation of the balloon 13, and the linear member 31 engages with the lesion 51 forming the narrowed portion, and this engagement serves as an anti-slip of the balloon 13. Is fulfilled. As a result, the balloon 13 is prevented from slipping from the stenosis when the balloon 13 is inflated, and the stenosis can be expanded well as shown in FIG. 5B.

  In this case, as described above, the distal end portion 33 of the linear member 31 is fixed to the inner peripheral surface of the same-diameter portion 45 of the distal-side fixing tube 41, and further the inner periphery of the same-diameter portion 45. Since the surface is separated from the outer peripheral surface of the inner tube 16, elastic deformation of the same diameter portion 45 is allowed. That is, a part of the load when the linear member 31 is in the overhanging state is received by elastic deformation of the same diameter portion 45. Therefore, the possibility that the linear member 31 is detached from the catheter tube 11 when the balloon 13 is inflated is reduced.

  Thereafter, the compressed air injected into the balloon 13 is extracted to contract the balloon 13, and the balloon catheter 10 is extracted from the body.

  Here, in the configuration in which the linear member 31 is provided so as to straddle the entire region of the balloon 13 in the longitudinal direction, as shown in FIG. It is conceivable that the linear member 31 is caught by the lesion part 51. If the balloon catheter 10 is extracted in this situation, the blood vessel 52 may be damaged. On the other hand, as described above, the adhesion between the distal end portion 33 of the linear member 31 and the same diameter portion 45 of the distal fixing tube 41 is greater than that when the balloon 13 is inflated with respect to the linear member 31. When a large predetermined tensile force is applied, the linear member 31 has a linear shape from the same diameter portion 45 at a stage before the proximal end portion 32 of the linear member 31 is detached from the outer tube 15 and the linear member 31 itself is broken. The adhesive strength is set so that the member 31 is detached. As a result, when the balloon catheter 10 is removed as shown in FIGS. 5D and 5E, the distal end portion 33 of the linear member 31 is detached from the catheter tube 11, and the balloon catheter 10 is removed. The free end of the linear member 31 that is removed from the catheter tube 11 is located at the end in the direction. Therefore, it is possible to release the state where the linear member 31 is caught by the lesion part 51. Even in this case, since the proximal end portion 32 of the linear member 31 is firmly fixed to the catheter tube 11, only the distal end portion 33 comes off preferentially, and the linear member 31. Is prevented from being released from the catheter tube 11 side.

  In particular, in this configuration, the distal end portion 33 of the linear member 31 is detached from the catheter tube 11 and the free end of the linear member 31 is positioned at the end in the extraction direction of the balloon catheter 10. The balloon catheter 10 can be satisfactorily extracted. For example, in the configuration in which the linear member 31 is detached at the proximal end portion 32, the free end of the linear member 31 is located on the distal end side in the extraction direction. In order to release the hooked state of the linear member 31, it is necessary for the free end of the linear member 31 to pass through the hooked portion, and in the situation where the free end is located at the proximal end portion 32, the hooked portion is free end. In order to pass through the balloon catheter 10, it is necessary to push the balloon catheter 10 in the insertion direction and pull out the balloon catheter 10 after the free end has passed through the hooked portion. Further, if the balloon catheter 10 is to be pulled out without being pushed in the insertion direction, the free end needs to be turned to the end side in the extraction direction so as to pass through the hooked portion, and there is a possibility that the hooked state cannot be released satisfactorily. is there. On the other hand, when the distal end portion 33 of the linear member 31 is detached, the free end of the hooked portion is successfully passed along with the extraction of the balloon catheter 10. Therefore, the extraction operation of the balloon catheter 10 in the above situation can be performed satisfactorily.

  In addition, since the free end of the linear member 31 is positioned at the end of the balloon catheter 10 in the extraction direction, it can be used against other lesions, bends, stents that have already been placed, etc. in the middle of the extraction path. It is possible to prevent the linear member 31 from being caught again.

  The force necessary for releasing the hooked state is such that it does not cause damage to a living body such as a blood vessel. The balloon catheter 10 is mainly passed through a blood vessel as described above and used for treating blood vessels such as coronary arteries, femoral arteries, and pulmonary arteries. It can also be applied to “tubes” and “body cavities”.

  According to the embodiment described in detail above, the following excellent effects are obtained.

  Adhesion between the distal end portion 33 of the linear member 31 and the distal fixing tube 41 is linear when a predetermined tensile force greater than that when the balloon 13 is inflated is applied to the linear member 31. Before the separation of the proximal end 32 of the member 31 from the outer tube 15 and the destruction of the linear member 31 itself, the bonding is performed such that the distal end 33 is detached from the distal fixing tube 41. Strength is set. Thereby, even if the linear member 31 is caught in a lesion or the like in the living body, the balloon catheter 10 can be satisfactorily extracted as described above.

  Further, since the distal end portion 33 of the linear member 31 is fixed to the distal-side fixing tube 41 with an adhesive, adjusting the type and application area of the adhesive, the above-mentioned Thus, the strength setting can be performed satisfactorily.

  Further, the distal end portion 33 of the linear member 31 is formed on the inner peripheral surface of the same-diameter portion 45 of the distal-side fixing tube 41 formed of a material that is more flexible than the inner tube 16 and the linear member 31. Furthermore, the inner peripheral surface of the same-diameter portion 45 is spaced from the outer peripheral surface of the inner tube 16. Thereby, when the balloon 13 is inflated, the same-diameter portion 45 is elastically deformed in accordance with the displacement of the linear member 31, and a part of the load applied to the linear member 31 during the displacement is received by the same-diameter portion 45. It is possible to prevent the linear member 31 from being separated from the catheter tube 11 when 13 is expanded.

  In particular, the first fixing ring portion 42 of the distal side fixing tube 41 is fixed so as to surround a part of the outer peripheral surface in the longitudinal direction of the inner tube 16 in the circumferential direction. Thereby, the distal side fixing tube 41 can be firmly fixed to the inner tube 16.

  Further, by fixing the distal end portion 33 of the linear member 31 that is preferentially removed when the linear member 31 is caught in the lesion, the distal end fixing tube 41 is fixed, so that it is caught in the living body. In the configuration in which the state can be satisfactorily released, when the balloon 13 is inflated, a part of the load at that time can be received by the distal side fixing tube 41, and the linear member 31 is detached during the inflation. Can be prevented. That is, according to this configuration, it is possible to satisfy both contradictory requirements of suppressing the separation of the linear member 31 when the balloon 13 is inflated and improving the release of the hooked state.

  In the configuration in which a plurality of linear members 31 are provided, the distal end portions 33 of all the linear members 31 are fixed to the distal side fixing tubes 41, and the above configuration relating to the release of the hooked state of all the distal end portions 33 Applied. Thereby, the said outstanding effect can be acquired about all the distal end parts 33. FIG. Further, the number of members constituting the balloon catheter 10 can be reduced as compared with a configuration in which an elastic body for fixing is individually provided for each linear member 31.

(Second Embodiment)
In the balloon catheter 60 of the present embodiment, the configuration relating to the fixing of the linear member 61 is different from that of the first embodiment. The difference will be described below with reference to FIG. FIG. 6 is a longitudinal sectional view of the balloon catheter 60.

  Similar to the balloon catheter 10 in the first embodiment, the balloon catheter 60 includes a balloon 62 and a linear member 61, and the linear member 61 is an entire region of the balloon 62 on the outer peripheral side of the balloon 62. Are provided so as to straddle in the longitudinal direction.

  Unlike the first embodiment, the proximal end portion 63 of the linear member 61 is directly fixed to the outer tube 64. Further, unlike the first embodiment, the distal end portion 65 of the linear member 61 is directly fixed to the inner tube 66. That is, unlike the first embodiment, the balloon catheter 60 does not include the proximal side fixing tube 37 and the distal side fixing tube 41, and the proximal end portion 63 of the linear member 61 is While being fixed to the outer tube 64 from the outside, the distal end portion 65 of the linear member 61 is fixed to the inner tube 66 from the outside.

  The proximal end 63 of the linear member 61 and the outer tube 64 are fixed using an adhesive. The distal end 65 of the linear member 61 and the inner tube 66 are also fixed using an adhesive. As this adhesive, those exemplified in the first embodiment can be used. In this case, the distal end portion 65 and the inner tube 66 are bonded to each other when the predetermined tensile force larger than that when the balloon 62 is inflated is applied to the linear member 61. The adhesive strength is set such that the distal end 65 of the linear member 61 is detached from the inner tube 66 before the part 63 is detached from the outer tube 64 and the linear member 61 itself is destroyed. Yes.

  Specifically, the adhesion of the proximal end portion 63 and the adhesion of the distal end portion 65 are performed by a cyanoacrylate adhesive. In this case, the application area of the adhesive at the adhesion portion of the distal end portion 65 is set smaller than the application area of the adhesive at the adhesion portion of the proximal end portion 63. The adhesive strength of the distal end portion 65 is lower than the strength. Further, the adhesive strength at the distal end portion 65 is such that when a tensile force is applied to the linear member 61 and the tensile force is increased, the adhesive before the linear member 61 itself breaks down. The layer is such that cohesive failure or interface failure occurs. As a result, as illustrated with reference to FIG. 5 in the first embodiment, even if the linear member 61 is caught in a lesion or the like in the living body, the release can be performed satisfactorily. it can.

  Needless to say, both the adhesive strength at the proximal end portion 63 and the adhesive strength at the distal end portion 65 are set to such an extent that cohesive failure or interface failure does not occur when the balloon 62 is inflated.

  Further, as a specific method for making the adhesive strength of the distal end portion 65 lower than the adhesive strength of the proximal end portion 63, instead of adjusting the application area, the proximal end portion 63 and the distal end portion 65 The adhesive strength of the distal end portion 65 may be made lower than the adhesive strength of the proximal end portion 63 by making the type of adhesive used at the end portion 65 different. More specifically, for the proximal end portion 63, an adhesive that provides an adhesive strength that causes a base material breakage upon breakage is used, and for the distal end portion 65, cohesive failure or interface breakage occurs upon breakage. An adhesive that provides a certain degree of adhesive strength may be used.

  In addition, the proximal end portion 63 and the outer tube 64 are fixed by at least one heat welding, and the distal end portion 65 and the inner tube 66 are fixed by using an adhesive as described above. The fixing strength of the distal end portion 65 may be lower than the fixing strength of the distal end portion 63.

(Third embodiment)
In the balloon catheter 70 of the present embodiment, the configuration relating to the fixing of the linear member 71 is different from that of the first embodiment. The difference will be described below with reference to FIG. FIG. 7 is a longitudinal sectional view of the balloon catheter 70.

  Similar to the balloon catheter 10 in the first embodiment, the balloon catheter 70 includes a balloon 72 and a linear member 71, and the linear member 71 is an entire region of the balloon 72 on the outer peripheral side of the balloon 72. Are provided so as to straddle in the longitudinal direction. Further, the proximal end portion 73 and the distal end portion 74 of the linear member 71 are made of a material that is more flexible than each of the tubes 75 and 76 and the linear member 71 (for example, illustrated in the first embodiment). It is fixed to fixing tubes 77 and 78 formed of thermoplastic elastomer).

  Specifically, a distal side fixing tube 77 is fixed to the inner tube 75 on the distal end side of the distal end side leg region of the balloon 72. The configuration of the distal side fixing tube 77 is the same as that of the distal side fixing tube 41 in the first embodiment, and includes a first fixing ring portion 81 and a second fixing ring portion 82. Yes.

  Further, in the outer tube 76, a proximal side fixing tube 78 is fixed to the proximal end side of the proximal end side leg region of the balloon 72. Similar to the distal side fixing tube 77, the proximal side fixing tube 78 includes a first fixing ring portion 83 and a second fixing ring portion 84. However, the proximal fixing tube 78 is fixed to the outer tube 76, and the outer tube 76 has an outer diameter larger than that of the inner tube 75. Accordingly, the proximal fixing tube 78 is formed so as to have an inner diameter and an outer diameter larger than that of the distal fixing tube 77 correspondingly.

  Similarly to the distal side fixing tube 41 in the first embodiment, the distal side fixing tube 77 is arranged such that the opening of the second fixing ring portion 82 faces the proximal end side of the balloon catheter 70. The first fixed ring portion 81 is fixed to the inner tube 75. In this case, the inner peripheral surface of the second fixed ring portion 82 is separated from the outer peripheral surface of the inner tube 75, and a predetermined space is formed between them.

  On the other hand, the proximal side fixing tube 78 is arranged so that the opening of the second fixing ring portion 84 faces the distal end side of the balloon catheter 70, and the first fixing ring portion 83 is fixed to the outer tube 76. Yes. In this case, the inner peripheral surface of the second fixed ring portion 84 is separated from the outer peripheral surface of the outer tube 76, and a predetermined space is formed between them.

  In the above configuration, the distal end portion 74 of the linear member 71 is bonded to the inner peripheral surface of the second fixing ring portion 82 in the distal side fixing tube 77, and the proximal end portion 73 of the linear member 71 is The proximal fixing tube 78 is bonded to the inner peripheral surface of the second fixing ring portion 84. Thus, by fixing the distal end portion 74 and the proximal end portion 73 to the flexible fixing tubes 77 and 78, respectively, the linear member 71 projects in accordance with the expansion of the balloon 72. In this case, both the proximal fixing tube 78 and the distal fixing tube 77 are elastically deformed, and the load applied to the linear member 71 is the proximal fixing tube 78 and the distal fixing tube. 77 will be received at both. Therefore, when the balloon 72 is inflated, the possibility that the linear member 71 is detached from the catheter tube 79 is reduced as compared with the first embodiment.

  Here, also in the present balloon catheter 70, when a predetermined tensile force larger than that when the balloon 72 is inflated is applied to the linear member 71, the linear member 71 is detached from the proximal-side fixing tube 78. The adhesive strength is set so that the linear member 71 is detached from the distal fixing tube 77 before the linear member 71 is destroyed.

  Specifically, the adhesion between the proximal end 73 of the linear member 71 and the distal fixing tube 77 and the adhesion between the distal end 74 of the linear member 71 and the proximal fixing tube 78 are: This is done with a cyanoacrylate adhesive. In this case, the distal end portion 74 of the linear member 71 and the distal side fixing are compared with the application area of the adhesive at the bonding portion between the proximal end portion 73 of the linear member 71 and the proximal side fixing tube 78. The application area of the above-mentioned adhesive in the bonding portion with the tube 77 is set to be small, and the bonding strength of the distal end portion 74 is lower than the bonding strength of the proximal end portion 73. Further, the adhesive strength at the distal end portion 74 is such that when a tensile force is applied to the linear member 71 and the tensile force is increased, the adhesive before the linear member 71 itself breaks down. The layer is such that cohesive failure or interface failure occurs. Thereby, as illustrated with reference to FIG. 5 in the first embodiment, even if the linear member 71 is caught in a lesion or the like in the living body, the release can be performed satisfactorily. it can.

  Needless to say, both the adhesive strength at the proximal end portion 73 and the adhesive strength at the distal end portion 74 are set to such an extent that cohesive failure or interface failure does not occur when the balloon 72 is inflated.

  Further, as a specific method for making the adhesive strength of the distal end portion 74 lower than the adhesive strength of the proximal end portion 73, instead of adjusting the application area, the proximal end portion 73 and the distal end portion 74 The adhesive strength of the distal end portion 74 may be made lower than the adhesive strength of the proximal end portion 73 by making the type of adhesive used for the end portion 74 different. More specifically, for the proximal end portion 73, an adhesive that provides an adhesive strength that causes a base material breakage at the time of breakage is used, and for the distal end portion 74, a cohesive failure or an interface breakage occurs at the time of breakage. An adhesive that provides a certain degree of adhesive strength may be used.

  In addition, the proximal end 73 and the outer tube 76 are fixed by at least one heat welding, and the distal end 74 and the inner tube 75 are fixed by using an adhesive as described above. The fixing strength of the distal end portion 74 may be lower than the fixing strength of the distal end portion 73.

(Fourth embodiment)
In the present embodiment, the configuration of the linear member is different from those of the above embodiments. Therefore, the configuration of the linear member 31 in the present embodiment will be described below with reference to FIG.

  The linear member 31 shown in FIG. 8 (a) is formed of the same material over the entire length thereof, and the region R1 is a region where the proximal fixing tube 37 is thermally welded. R2 is a region corresponding to the proximal end side leg region 21 and the proximal end side cone region 22 of the balloon 13, the region R3 is a region corresponding to the straight tube region 23 of the balloon 13, and the region R4 is the region of the balloon 13. The region corresponding to the distal end side cone region 24 and the distal end side leg region 25 is a region where the region R5 is bonded to the distal side fixing tube 41.

  Unlike the above embodiments, the linear member 31 has a breaking strength from the center to the distal end when the breaking strength from the center to the proximal end is compared with the breaking strength from the center to the distal end. Is formed to be lower. Further, the breaking strength set to be low is set lower than the strength at each of the fixed positions on the distal end side and the proximal end side of the linear member 31.

  Specifically, the cross-sectional area of the cross section (surface orthogonal to the longitudinal direction) of the linear member 31 is formed so as to change stepwise along the longitudinal direction. That is, the cross section of the region R3 has a triangular shape as shown in FIG. Further, as shown in FIG. 8B, the cross section of the region R1 and the region R2 has a trapezoidal shape with the upper corner portion cut off in the cross section of the region R3, and the cross-sectional area is next to the region R3. It is a big one. Further, as shown in FIG. 8D, the cross section of the region R4 has a trapezoidal shape with the upper side cut out in the cross sections of the region R1 and the region R2, and the cross-sectional area is next to the regions R1 and R2. It is a big one. Further, as shown in FIG. 8E, the cross section of the region R5 has a trapezoidal shape with the upper side cut away in the region R4, and the cross-sectional area is minimum.

  According to the above configuration, the breaking strength of the linear member 31 is region R3> region R1, R2> region R4> region R5. Thereby, even if the linear member 31 is caught in a lesion or the like in the living body, the linear member 31 has a fragile portion (region R4 or region R5) having a low breaking strength. When the catheter 10 is to be extracted from the living body, the linear member 31 is broken at the weakened portion, and the hooked state can be released.

  Further, when the linear member 31 is broken, the broken portion is on the distal end side with respect to the center, and each divided piece of the linear member 31 divided by the breaking is on the distal end side with respect to the proximal end side. Is shorter. Of the divided pieces of the linear member 31, the free end of the divided piece on the proximal end side is located on the distal side in the extraction direction of the balloon catheter 10 with respect to the fixed end, and Is located on the distal end side in the extraction direction of the balloon catheter 10 with respect to the fixed end. In this case, when the balloon catheter 10 is removed, the other lesioned part, the bent part, or the like in the middle of the extraction path is already placed in the distal end side divided piece compared to the proximal end side divided piece. It is thought that it is easily caught on a stent or the like. On the other hand, when the balloon catheter 10 is withdrawn, each piece of the linear member 31 divided by breaking as described above is made shorter on the distal end side than on the proximal end side. The possibility of occurrence of catching of the divided pieces at is reduced. Moreover, according to this structure, the said effect can be acquired with the comparatively simple structure of adjusting the cross-sectional area of the linear member 31. FIG.

  The configuration of the linear member 31 is limited to the above as long as the breaking strength of the linear member 31 itself can be lower on the distal end side than on the proximal end side. For example, the cross-sectional area of the cross section may be changed to two stages, three stages, or five stages or more instead of four stages. Further, the weakened portion may be formed by cutting or the like on the distal end side from the center of the linear member 31 within a range where the strength does not become weaker than the fixed portion on the distal end side of the linear member 31.

(Other embodiments)
The present invention is not limited to the description of the above embodiments, and may be implemented as follows, for example.

  (1) In each of the above embodiments, the linear members 31, 61, 71 are provided as the elongated elements for suppressing the slipping when the balloons 13, 62, 72 are inflated. Instead, as the elongated elements, In addition, a linear member for a cutting blade for incising a lesion portion when the balloons 13, 62, 72 are inflated may be provided. In this case, the linear member is formed of stainless steel or the like, and the strength of the linear member itself is higher than that of the linear members 31, 61, 71 in the above embodiments. Moreover, you may provide the linear member for imaging | contrast for confirming the position of the balloon 13,62,72 inserted in the living body as an elongate element out of the body. In this case, the linear member is formed of a Ni—Ti alloy or the like, and the strength of the linear member itself is higher than that of the linear members 31, 61, 71 in the above embodiments. Even in these configurations, by applying the configuration in each of the above embodiments, the separation of the linear members 31, 61, 71 when the balloons 13, 62, 72 are inflated and the release of the hooked state are eliminated. It is possible to satisfy both conflicting requirements for improvement. A strip-shaped element may be used as the elongated element.

  (2) In the first embodiment, when the distal end portion 33 of the linear member 31 is detached from the catheter tube 11, the distal end portion 33 causes the adhesive layer 46 to undergo cohesive failure or interface failure. The distal end 33 is fixed to the distal side fixing tube 41 so that the base material of the distal side fixing tube 41 is destroyed. You may make it fix to. However, in this configuration, when the tensile force is applied to the linear member 31, the strength of the distal-side fixing tube 41 against the tensile force as a base material is the proximal end of the linear member 31. It is necessary to select the material of the distal side fixing tube 41 so as to be lower than the fixing portion of the part and the linear member 31 itself. In this configuration, since the distal fixing tube 41 needs to be broken, the strength required until the distal end portion 33 of the linear member 31 is detached may be higher than that in the first embodiment. However, the hooked state can be released by pulling out the balloon catheter 10. In this configuration, the distal end portion 33 of the linear member 31 may be fixed by thermal welding of the distal side fixing tube 41. Further, this configuration may be applied to the third embodiment.

  (3) When a tensile force is applied to the linear members 31, 61, 71, the strength against the tensile force is closer to the proximal end side of each of the fixed portions of the linear members 31, 61, 71. May be configured to be lower than the distal end side. The said structure is realizable by reversing the structure regarding fixation of the distal end part of the linear members 31, 61, 71 in each said embodiment, and the structure regarding fixation of a proximal end part. Even in this configuration, even if the linear members 31, 61, 71 are caught on a lesion in a living body, the proximal end can be detached by pushing the balloon catheters 10, 60, 70 again. It is possible to release the hooked state with the proximal end portion as a free end.

  (4) In the first embodiment, at least one of the proximal side fixing tube 37 and the distal side fixing tube 41 is fixed to the portion of the catheter tube 11 where the leg region of the balloon 13 is fixed. May be. In the second embodiment, at least one of the proximal end portion 63 and the distal end portion 65 of the linear member 61 is fixed to the place where the leg region of the balloon 62 in the catheter tube 68 is fixed. May be. Further, in the third embodiment, at least one of the distal side fixing tube 77 and the proximal side fixing tube 78 is fixed to the portion of the catheter tube 79 where the leg region of the balloon 72 is fixed. May be. Moreover, in each said embodiment, a part of area | region which straddles a balloon in a linear member may be fixed to the expansion | swelling area | region of a balloon.

  (5) In the first embodiment, the distal-side fixing tube 41 formed in an endless ring shape is used. Instead, a far end formed in a ring shape having a closed end such as a C-shaped cross section is used. A distal side fixing tube may be used. Further, an elliptical distal fixation tube may be used instead of a circular cross section. Such a configuration may be applied to the third embodiment.

  (6) In the first embodiment, the proximal-side fixing tube 37 formed in an endless annular shape is used. Instead, a proximal end-shaped annular shape such as a C-shaped cross section is used instead. A distal side fixing tube may be used. Moreover, you may use the tube for a proximal side fixation of an elliptical shape instead of a cross section.

  Further, the proximal side fixing tube 37 may be omitted, and the proximal end portion 32 of the linear member 31 may be directly fixed to the outer tube 15. In this case, if both are fixed using an adhesive, it is performed firmly like the fixing of the proximal fixing tube 37 and the outer tube 15 using the adhesive in the first embodiment. Like that. Accordingly, when the linear member 31 is caught in the living body, the distal end portion 33 of the linear member 31 can be preferentially removed when the balloon catheter 10 is extracted. The same effects as those of the first embodiment can be obtained. The proximal end portion 32 of the linear member 31 may be fixed to the outer tube 15 by heat welding.

  (7) The linear member having a fragile portion as in the fourth embodiment is applied to the first embodiment, the second embodiment, or the third embodiment. May be. In this case, the breaking strength of the fragile portion in the linear member is higher than the strength of the fixed portion on the distal end side of the linear member, and when the hooked state of the linear member is released, the fixed portion on the distal end side is released. The linear member will come off. However, even in this configuration, the linear member may be broken, and in this case, it is broken at the fragile portion, so that the effect described in the fourth embodiment can be obtained. .

  (8) In each of the above embodiments, the inner tube may have a configuration in which a tip end body is attached to the distal end portion thereof. In this case, you may make it fix the distal end side leg area | region of a balloon, the distal end part of a linear member, or the tube for fixation to the said tip part. A balloon catheter may be used for stent expansion.

1 is a schematic overall side view showing a configuration of a balloon catheter according to a first embodiment. (A) is a schematic side view which shows the structure of the balloon in the contracted state, and its periphery, (b) is a cross-sectional view of Fig.2 (a). (A) is a schematic side view which shows the structure of the balloon in the inflated state, and its periphery, (b) is a cross-sectional view of Fig.3 (a). 3A is a longitudinal sectional view of FIG. 3A, FIG. 4B is an enlarged view of a region C1 in FIG. 4A, and FIG. 4C is an enlarged view of a region C2 in FIG. Explanatory drawing for demonstrating the usage method of a balloon catheter. The longitudinal cross-sectional view of the balloon catheter in 2nd Embodiment. The longitudinal cross-sectional view of the balloon catheter in 3rd Embodiment. Explanatory drawing for demonstrating the structure of the linear member in 4th Embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Balloon catheter, 11 ... Catheter tube, 13 ... Balloon, 31 ... Linear member, 41 ... Fixing tube, 43 ... 2nd fixing ring part, 60 ... Balloon catheter, 61 ... Linear member, 62 ... Balloon, 68 ... catheter tube, 70 ... balloon catheter, 71 ... linear member, 72 ... balloon, 77 ... distal fixation tube, 78 ... proximal fixation tube, 79 ... catheter tube, 82 ... second fixation ring, 83 ... 2nd stationary ring part.

Claims (10)

A catheter tube;
A hollow balloon provided on the distal end side of the catheter tube so as to cover the catheter tube from the outside and inflating or deflating when fluid flows through the fluid lumen of the catheter tube;
The balloon is provided so as to straddle at least the inflation region in the longitudinal direction, the proximal end is fixed to the proximal side of the inflation region, and the distal end is distal to the inflation region. Elongate element that is displaced and is displaced radially outward of the balloon following the inflation of the balloon;
With
One of the fixing points on the proximal end side or the distal end side of the elongated element has a strength against the tensile force when a tensile force is applied to the elongated element. A balloon catheter characterized in that the balloon catheter is set lower than the other of the fixed portions on the side and the elongated element itself. A catheter tube;
A hollow balloon provided on the distal end side of the catheter tube so as to cover the catheter tube from the outside and inflating or deflating when fluid flows through the fluid lumen of the catheter tube;
The balloon is provided so as to straddle at least the inflation region in the longitudinal direction, the proximal end is fixed to the proximal side of the inflation region, and the distal end is distal to the inflation region. Elongate element that is displaced and is displaced radially outward of the balloon following the inflation of the balloon;
With
The fixing point on the distal end side of the elongated element has a strength against the tensile force when a tensile force is applied to the elongated element, and the fixing point on the proximal end side of the elongated element and the elongated element A balloon catheter characterized by being set lower than itself.   The elongate element is fixed to an object to be fixed using an adhesive on at least a side where the strength against the tensile force is set low in each fixing portion of the elongate element. The balloon catheter according to 1 or 2. An adhesive layer made of the adhesive is formed between the elongated element and the object to be fixed on the side where the strength against the tensile force is set low in each of the fixing points of the elongated element,
4. The adhesive layer according to claim 3, wherein when a predetermined tensile force is applied, cohesive failure or interface failure of the adhesive layer occurs before the elongated element and the base material to be fixed are destroyed. Balloon catheter.   An elastic body is further provided that is provided on the side where the strength against the tensile force is set low in each of the fixed portions of the elongate element and elastically deforms in accordance with the displacement of the elongate element when the balloon is inflated. The balloon catheter according to any one of claims 1 to 4, wherein:   Of the fixed portions of the elongate element, provided on the side where the strength against the tensile force is set to be low, it has an endless or endless annular shape, and further part of the outer peripheral surface in the longitudinal direction of the catheter tube And a second ring that is fixed in a state of covering the end of the elongated element from the outside and elastically deforms in accordance with the displacement of the elongated element when the balloon is inflated. The balloon catheter according to claim 1, further comprising an elastic body integrally formed with the portion.   The second annular portion has an inner circumferential surface spaced outward from the outer circumferential surface of the catheter tube, and an end of the elongated element is fixed to the inner circumferential surface of the second annular portion. The balloon catheter according to claim 6. Of each of the fixing points of the elongated element, the side set with a low strength against the tensile force is the distal end side,
The first ring part and the second ring part are continuously formed so as to be located on the same axis,
Further, the elastic body is arranged such that the first ring portion is located on the distal end side, and a space between the inner peripheral surface of the second ring portion and the outer peripheral surface of the catheter tube is close. It is open toward the top end side,
The distal end portion of the elongated element is inserted between the second ring portion and the catheter tube from the opened side, and is fixed to the inner peripheral surface of the second ring portion. The balloon catheter according to claim 7.   A plurality of the elongate elements are provided, and end portions on the elastic body side of the elongate elements are all fixed to the second ring portion of the elastic body. The balloon catheter according to 1. A catheter tube;
A hollow balloon provided on the distal end side of the catheter tube so as to cover the catheter tube from the outside and inflating or deflating when fluid flows through the fluid lumen of the catheter tube;
The balloon is provided so as to straddle at least the inflation region in the longitudinal direction, the proximal end is fixed to the proximal side of the inflation region, and the distal end is distal to the inflation region. Elongate element that is displaced and is displaced radially outward of the balloon following the inflation of the balloon;
With
2. The balloon catheter according to claim 1, wherein the elongate element has a region where the breaking strength of the elongate element itself is set lower than that at the proximal end side from the center, at the distal end side from the center in the longitudinal direction.

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