JP2007301062A - Stent delivery catheter and balloon for stent delivery catheter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a stent delivery catheter which shows trackability performance equivalent to that of a delivery catheter without a mechanism of preventing stent movements and increases strength against a fall of the stent, and a balloon for a stent delivery catheter. <P>SOLUTION: The stent delivery catheter showing the trackability performance equivalent to that of the delivery catheter without the mechanism 6 of preventing stent movements is constituted by increasing the strength against the fall of the stent 5 through forming the mechanism 6 of preventing stent movements on the surface of the balloon and by retaining flexibility through forming the mechanism 6 at least partially on the surface of the balloon. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a stent delivery catheter used for inserting a stent into a blood vessel, an esophagus, a trachea, a urethra, a bile duct or the like to expand the inside of the tube and maintain a body cavity, and a balloon for the stent delivery catheter.

  Stents are widely used to expand a stenosis formed in a body vessel and secure a path. A stent is folded and placed in a catheter called a delivery catheter, inserted into the body, and expanded.

  There are two types of known delivery catheters. One is a balloon-expandable stent in which a balloon expanded by a pressure fluid using a conventional balloon catheter expands the stent by its expansion force. is there. The other is a self-expandable stent having an expandability formed by a shape memory alloy or the like.

  In the case of balloon expandable stents, the stent was folded and clamped to the shaft to attach the stent to the delivery catheter. However, in order to hold the stent, the clamping force of the stent from the outside is weak, and the stent is bent at the bent part of a blood vessel such as a blood vessel due to friction with the hemostack valve and the guide catheter during insertion and friction in the meandering vessel. There is a possibility that the stent may be displaced from the initial placement position of the balloon catheter or may be dropped due to being caught or frictional resistance thereof. If it deviates from the initial arrangement position, the stent does not expand uniformly and the stenosis cannot be expanded sufficiently. In addition, if it falls off, it may remain in the body and is dangerous. The following prior art documents disclose methods for preventing such movement and dropping of the stent.

  In Patent Document 1, it is disclosed that a plurality of protrusions (projections) are provided on the surface of the balloon, thereby preventing the stent from falling off by hooking the stent onto the protrusion or embedding it on the protrusion. Yes.

  However, with this technique, it is difficult to form protrusions on the balloon surface and the inner surface, and there is concern that the protrusions may be caught and embedded in a stent having a complicated shape.

  In Patent Document 2, the movement of the stent is suppressed by hooking the stent by providing a ridge in the circumferential direction of the balloon surface.

  Also by this technique, since a ridge is provided in the circumferential direction of the balloon to form the balloon in a pleat shape, a crimping profile (an outer diameter of the stent after the stent is folded) is increased. Increasing the crimping profile increases the shaft diameter at the catheter tip and decreases flexibility.

  Patent Document 3 also discloses a technique of increasing the drop-off strength by embedding a stent in the outer layer of the balloon by making the balloon into a multilayer. Since it is a multi-layer balloon, there is a problem that the stent diameter after folding becomes large and the trackability performance (trackability to the inside of the blood vessel) deteriorates.

In these prior arts, protrusions and multilayers are formed on the entire surface of the balloon. When the stent is folded and arranged using such a method, the crimping profile becomes large as compared with a case where a mechanism for preventing the movement of the stent is not included. Increasing the crimping profile increases the shaft diameter at the distal end of the catheter. Therefore, since the flexibility is deteriorated, there is a problem that the passage resistance is increased at the time of entering the blood vessel, and the trackability performance is deteriorated.
Special table 2002-539888 Special table 2004-527285 Special table 2001-505116

  The problem to be solved by the present invention is to provide a delivery catheter and a balloon for stent delivery catheter that have the same trackability performance as that of a delivery catheter without a stent movement prevention mechanism and have improved stent dropout strength.

In order to solve the above problems, the present invention has the following features.
(1) One of the features of the present invention is a balloon for a stent delivery catheter connected to a stent delivery catheter, wherein the balloon is provided at a straight tube portion and at least one end of the straight tube portion. The tapered portion has a sleeve portion at an end portion of the tapered portion, and the balloon is further provided with a stent movement prevention mechanism on at least a part of the surface of each portion.
(2) In another feature of the present invention, at least a part of the stent movement prevention mechanism is fixed to the balloon.
(3) Another feature of the present invention is that the stent movement prevention mechanism further includes a distal end portion and a rear end portion extending in a longitudinal direction coinciding with the catheter axial direction, and at least a part of the distal end portion is the balloon. The rear end portion is fixed to either the sleeve portion or the taper portion on the rear end side of the balloon, and is fixed to the straight tube portion of the balloon. Is not fixed.
(4) Another feature of the present invention is that the stent movement prevention mechanism further includes a distal end portion and a rear end portion extending in a longitudinal direction coinciding with the catheter axial direction, and the distal end portion is on a distal end side of the balloon. The rear end portion exists on the straight tube portion or the taper portion or the sleeve portion on the rear end side of the balloon, but is not fixed.
(5) Another feature of the present invention is that the stent movement prevention mechanism further includes a distal end portion and a rear end portion extending in a longitudinal direction coinciding with a catheter axial direction, and the rear end portion is a rear end of the balloon. It is fixed to a sleeve portion or a taper portion on the side, and the tip portion exists on the straight tube portion of the balloon or on the taper portion or sleeve portion on the tip portion side but is not fixed.
(6) Another feature of the present invention is that the balloon is folded around the catheter axial direction, and the stent movement prevention mechanism is provided at least in a portion corresponding to the outside of the folded balloon. Is fixed.
(7) Another feature of the present invention is that the stent is further folded at least partially in a portion corresponding to the inside of the folded balloon, the balloon being folded about the catheter axial direction. Is fixed.
(8) Another feature of the present invention is that the longitudinal direction of the stent movement prevention mechanism is coincident with the catheter axial direction.
(9) According to another feature of the present invention, the longitudinal direction of the stent movement prevention mechanism coincides with the circumferential direction of the catheter.
(10) Another feature of the present invention is that the stent movement prevention mechanism is made of resin.
(11) Another feature of the present invention is that the Shore D hardness of the resin is equal to or lower than the Shore D hardness of the balloon.
(12) Another feature of the present invention is that the stent movement prevention mechanism is in the form of a film.
(13) Another feature of the present invention is a balloon with a stent, wherein the stent is fixed to any one of the balloons via the stent movement prevention mechanism.
(14) Another feature of the present invention is a stent delivery catheter characterized in that any one of the balloons or the balloon with a stent is connected.

  Other features of the present invention and their advantages will become apparent from the following embodiments and drawings.

  According to the present invention, the stent drop-off strength is increased by forming a stent movement prevention mechanism on the balloon surface, and the flexibility is maintained by at least partial formation on the balloon surface, and there is no stent movement prevention mechanism. Provided are a stent delivery catheter and a stent delivery catheter balloon having trackability performance equivalent to the case.

  Embodiments of a catheter and a balloon according to the present invention will be described below with reference to the drawings. The catheter as an embodiment of the present invention can take any structure of a known fast exchange type catheter as shown in FIG. 1 and an over-the-wire type catheter shown in FIG. The catheter of the embodiment is not limited as long as it has a balloon on the distal end side of the catheter, and includes a tube or lumen for flowing pressure fluid through the balloon, and a tube or lumen for passing a guide wire. A stent delivery catheter obtained by providing a stent movement prevention mechanism at least partially on the surface of a medical balloon.

Hereinafter, the structure of the stent delivery catheter will be described in detail with reference to a coaxial type high-speed exchange type in which an outer tube and an inner tube are coaxial, and embodiments of the present invention (such as a balloon provided in the catheter) will be described in detail. .
1. As shown in FIG. 3, the medical balloon 1 in the embodiment of the overall configuration of the balloon has a cylindrical straight tube portion 2, a conical tip tapered portion 3 a on the tip side of the straight tube portion 2, and a conical shape on the rear end side. And a rear end taper portion 3b. As shown in FIG. 3, the front end side taper portion 3a has a columnar front end sleeve portion 4a at the front end, and a rear end side taper portion 3b has a cylindrical rear end sleeve portion 4b at the rear end. Preferably there is. Each of the straight pipe portion 2, each sleeve portion, and each taper portion has an example of a cylindrical shape or a conical shape as an example. However, the shape is not limited to such a shape, and a shape well known to those skilled in the art is adopted. Also good.

As an example different from the embodiment, when a stent in a contracted state is placed by folding a balloon provided in a stent delivery catheter that does not have a stent movement prevention mechanism to be described later, since it is held only by the clamping force of the stent, Friction with the hemostack valve and guide catheter that occurs when the stent is inserted into the body, and friction within the meandering vessel, can cause the stent to move or fall off the surface of the balloon.
2. The stent movement-preventing mechanism Therefore, in this embodiment, is disposed stent movement prevention mechanism 6 is the balloon 1 on the surface, as shown in FIG. 4, by which the stent 5 is placed thereon, the stent movement prevention mechanism of the stent 5 6 Indentation and friction are generated on the surface, and the stent 5 can efficiently prevent movement on the stent delivery catheter, and the most dangerous stent can be prevented from falling off. The structure and number of the stent movement prevention mechanisms 6 can be changed by means well known to those skilled in the art, as illustrated in the embodiments described later.

  In a more preferred embodiment, as shown in FIG. 5, the stent movement prevention mechanism 6 may be disposed at least partially on the balloon surface. In the embodiment in which the stent movement prevention mechanism 6 is partially provided on the surface of the balloon 1, the stent crimping profile can be reduced, flexibility is not impaired, and the trackability performance is greatly different from the case where the stent is simply clamped to the catheter. It is preferable in that it can be suppressed to the extent that there is no occurrence.

As another embodiment of the stent movement prevention mechanism 6, as shown in each of FIGS. 6a, b, c and FIG. 7, at least a part thereof may be fixed to the balloon. By reducing the number of fixing parts, hardening around the fixing part and an increase in profile can be prevented. When the number of fixing parts is not reduced, productivity increases slightly due to an increase in fixing work (manufacturing man-hours) as the number of fixing parts increases.
The stent movement prevention mechanism 6 may not be fixed to the balloon straight tube portion 2 (see FIG. 3). Specifically, as shown in FIG. 8, the distal end side of the stent movement prevention mechanism 6 is fixed to the distal end side sleeve portion 4a or the distal end side tapered portion 3a, and the rear end side is rear end side tapered portion 3b or rear end side sleeve portion 4b. It may be fixed to. In the drawing, an example in which three stent movement prevention mechanisms 6 are arranged is shown. However, the embodiment is not limited to three, and the effect of the stent movement prevention mechanism 6 can be obtained as long as the number is one or more. In a preferred embodiment, the number of stent movement prevention mechanisms 6 is the same as the number of balloons folded.

Moreover, it is not necessary to fix both the front end side and the rear end side of the stent movement preventing mechanism 6 to the balloon 1 (see FIG. 3), and may be fixed to either one as shown in FIGS. When only one side is fixed, the length of the stent movement prevention mechanism 6 in the longitudinal direction does not need to reach from the front end side sleeve 4a to the rear end side sleeve 4b, but from the fixed end to the balloon straight tube portion 2. It is sufficient that the stent movement prevention mechanism 6 exists on the lower side of the stent 5. In the drawing, an example in which three stent movement prevention mechanisms 6 are arranged is shown, but the embodiment is not limited to three, and the above-described effects can be achieved if one or more. In a preferred embodiment, the number of stent movement prevention mechanisms 6 is the same as the number of balloons folded. When the stent movement preventing mechanism 6 is not fixed on the balloon straight tube portion 2, the distal end side of the stent movement preventing mechanism 6 is hooked on the distal end side sleeve portion 4a of the balloon as shown in FIG. The rear end side may be hooked on the balloon rear end side sleeve portion 4b.
3. Stent Crimping To crimp a stent, the stent is placed by folding the balloon into several sheets and wrapping it along the inner center around the catheter axis. It is possible to fold the balloon into two or more by techniques known to those skilled in the art. As for the method of winding, as long as there are two sheets, a method of winding a folded balloon in the same rotational direction (S wrap) and a method of winding each in the opposite direction (C wrap) can be used. If there are three or more sheets, a method of winding in the same direction is generally used.

The arrangement of the stent movement prevention mechanism after folding is such that when the balloon is folded into at least two sheets and wound around the catheter axial direction, the outer surface of the balloon wall (see FIG. 12) becomes the outer side as shown in FIG. 12a), or a portion corresponding to the inside of the folded balloon (FIG. 12b) is preferred. More preferably, the stent movement prevention mechanism 6 is fixed at least partially on the surface of the balloon 1.
4). Other Variations of Stent Movement Prevention Mechanism A plurality of modifications of the stent movement prevention mechanism 6 will be described with reference to the drawings.

  On the surface of the balloon, as shown in FIG. 13a, the longitudinal direction of the stent movement preventing mechanism 6 is arranged so as to coincide with the catheter axial direction, and has the same length as the straight tube portion of the balloon. A stent is placed. As shown in FIG. 13b, the length of the stent movement preventing mechanism 6 in the longitudinal direction may be shorter than the length of the balloon straight tube, or may be two or more rows in the catheter axial direction. Moreover, it may be arranged at intervals, and when the arrangement is further separated at intervals (FIG. 13c), or the stent movement prevention mechanism 6 may be combined with a long one and a short one (FIG. 13d). ).

In the drawing, only three rows are arranged with respect to the circumference of the balloon surface, but the embodiment is not limited to three rows. The number is preferably the same as the number of folded balloons. If one or more rows are arranged, the function can be exhibited.
As shown in FIG. 14a, the longitudinal direction of the stent movement prevention mechanism 6 is arranged on the surface of the catheter so as to coincide with the circumferential direction of the catheter. Also in this case, a plurality of the stent movement prevention mechanisms 6 may be arranged in a case where the longitudinal direction makes one round of the circumference and shorter than the circumference of the balloon straight tube as shown in FIG. 14b. A plurality of arrangements may be arranged apart from each other (FIG. 14c). Further, it may be in a combined state (FIG. 14d) in which one round is made or a plurality of rounds are arranged. In the drawing, the arrangement is made in three rows with a predetermined length with respect to the circumference of the balloon surface. However, the number and length are not limited to this, and one or more rows are arranged in other lengths. Even if it exists, there exists the above-mentioned effect regarding the stent movement prevention mechanism 6.
5. Example of material for stent movement prevention mechanism Here, the stent movement prevention mechanism 6 is preferably made of a resin, and as a material, polyolefin, polyolefin elastomer, polyester, polyester elastomer, polyamide, polyamide elastomer, polyurethane, polyurethane elastomer, or the like can be used.

  More preferably, the Shore D hardness of the resin is equal to or lower than that of the balloon. Furthermore, it is preferable to produce it into a film shape (film thickness 5-50 micrometers).

In order to produce a resin in the form of a film, it is optimal to process the heated resin into a thin plate with a press, but there are other methods that can be processed into a film, such as injection molding, blow molding, and dipping. Not limited. By making it into a film, the thickness can be controlled, processing is easy, and placement on the delivery catheter is also easy.
6). Example of balloon material The material of the medical balloon 1 does not affect the effect of the present invention as long as it is a biaxially stretchable material. Polyolefin, polyolefin elastomer, polyester, polyester elastomer, polyamide, polyamide Elastomer, polyurethane, polyurethane elastomer and the like can be used, and polyester, polyester elastomer, polyamide, and polyamide elastomer are preferable from the viewpoint of realizing a compressive strength that sufficiently expands the stent.
7). Balloon Manufacturing Method A balloon is produced by blow molding in which pressure is applied in a heated mold using a tube called a parison. The method for producing the balloon is not limited to this method, and may be a method for producing the balloon by dipping a resin on the outside of the mold. As a method for producing a balloon, there are dipping molding, blow molding and the like, and it is possible to select a suitable method. However, blow molding is preferable in order to realize sufficient pressure resistance necessary for a balloon for stent expansion. . For example, a tubular parison having an arbitrary size is first formed by extrusion molding or the like. A balloon having the same shape as the mold shape can be formed by disposing the tubular parison in a mold having a shape corresponding to the balloon shape and stretching it in the axial direction and the radial direction by a biaxial stretching process. . The axial stretching may be performed simultaneously with or before or after the radial stretching, and may be annealed to stabilize the shape and dimensions of the balloon.
8). Examples of materials of inner tube, outer tube, and hub The material of the inner tube 7 does not affect the effect of the present invention and is not particularly limited. In the case of a coaxial structure having a double pipe on the same axis, polyolefin, polyolefin elastomer, polyester, polyester elastomer, polyamide, polyamide elastomer, polyurethane, polyurethane elastomer, etc. can be used as the inner tube 7, depending on the inner surface of the inner tube 7. Since the guide wire lumen is defined, in consideration of the sliding property of the guide wire, polyethylene, particularly high-density polyethylene is preferable. Further, the inner tube 7 may have a multilayer structure, and the innermost layer may be made of a high-density polyethylene and the outermost layer may be made of a material that can be bonded or fused to the balloon 1 in order to ensure the slidability of the guide wire. Further, in order to further improve the slidability of the guide wire, it is possible to apply a lubricious coating such as silicon or polytetrafluoroethylene on the inner surface of the inner tube 7. Even in the case of a biaxial structure in which tubes are arranged in two rows in parallel or in other cases, it is possible to select a suitable material in consideration of the above contents.

  The material of the outer tube 8 is not particularly limited as in the case of the inner tube 7, and polyolefin, polyolefin elastomer, polyester, polyester elastomer, polyamide, polyamide elastomer, polyurethane, polyurethane elastomer, and the like can be used.

  As the material constituting the hub 9, polycarbonate, polyamide, polyurethane, polysulfone, polyarylate, styrene-butadiene copolymer, polyolefin, and the like can be suitably used.

The method for joining the balloon, the outer tube, and the inner tube is not particularly limited, and known adhesion, fusion, and the like can be used. Further, the composition and chemical structure of the adhesive used and the curing type are not limited. From the point of composition and chemical structure, adhesives such as urethane type, silicone type, epoxy type and cyanoacrylate type can be used. From the point of curing type, two-component mixed type, UV curable type, water absorption curable type Adhesives such as heat curing type and radiation curing type can be used. However, when an adhesive is used, the rigidity of the joint does not change discontinuously before and after the joint at the joint between the rear end sleeve portion of the balloon and the outer tube and between the balloon front end sleeve portion and the inner tube. It is preferable to use an adhesive having a degree of hardness after curing, which can be selected in consideration of the rigidity of the balloon, outer tube, and inner tube.
9. The placement of the stent movement-preventing mechanism 6 to Installation balloon 1 on the surface of the stent movement-preventing mechanism 6 can fusion or adhesion. For the installation of the stent movement prevention mechanism on the surface of the balloon 1, a method of applying an adhesive between the balloon and the stent movement prevention mechanism and providing an adhesive layer or bonding the material of the stent movement prevention mechanism to a liquid surface It may be coated and dried and fixed. As the adhesive, urethane type, silicone type, epoxy type, cyanoacrylate type and the like, which are the same as those for the balloon, outer tube, and inner tube, can be used. Adhesives such as liquid mixing type, UV curable type, water absorption curable type, heat curable type, and radiation curable type can be used. More preferably, the Shore hardness of the adhesive is also smaller than that of the balloon material. Further, if the balloon surface and the stent movement prevention mechanism are compatible, they may be fixed by welding with a laser or heat induction. If necessary, the fixing force may be increased by activating the interface by plasma irradiation or the like.

In addition, a hydrophilic coating can be applied to the outer surface of the stent delivery catheter to facilitate insertion. That is, it is preferable to apply a hydrophilic coating that exhibits lubricity when in contact with blood to a portion that comes into contact with blood. The kind of hydrophilic coating is not particularly limited, and hydrophilic polymers such as poly (2-hydroxyethyl methacrylate), polyacrylamide, and polyvinylpyrrolidone, or blends thereof can be suitably used, and the coating method is not particularly limited.
10. Stent The stent according to the present invention (for example, a body cavity opening stent) may be a balloon expandable stent, and the material is not particularly limited, but stainless steel such as SUS316L, cobalt chromium alloy, or the like can be used. Further, the design of the stent is not limited at all.
11. Stent delivery catheter As an example of the “stent delivery catheter” according to the present invention, a catheter described in Example 1 described later is connected to a balloon crimped with the stent (corresponding to “balloon with stent”), for example. Is mentioned. In addition to the catheter shown in Example 1, a catheter produced by means well known to those skilled in the art can be used. The catheter preferably has a flexible shaft. A fluid supply port may be provided on the rear end side of the shaft.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited at all by these Examples.

Example 1
A catheter was prepared according to the procedure described below. The overall structure of the catheter of Example 1 and the description of the structure are the same as the structure illustrated in FIGS. 1 and 3 and the description of each structure described in the above embodiment.

  A tube-shaped parison (inner diameter 0.45 mm, outer diameter 0.87 mm) was prepared by extrusion molding using a polyamide elastomer (trade name: PEBAX7233SA01; manufactured by elfatochem), and then biaxially stretched blow using this parison. The outer diameter of the straight pipe portion is 3.00 mm × length 18 mm by molding, the thickness of the tip side taper portion is approximately 22 μm, the thickness of the straight tube portion is substantially center portion is 17 μm, and the thickness of the rear end side taper portion is substantially center portion. A balloon having a thickness of 25 μm was produced. In addition, the thickness of the front-end side taper part substantially center part, the straight pipe part substantially center part, and the rear-end side taper part substantially center part was measured using the micrometer.

  The inner tube (inner diameter: 0.42 mm, outer diameter: 0.56 mm) and outer tube (inner diameter: 0.76 mm, outer diameter: 0.90 mm) were prepared by extrusion molding using polyamide elastomer (trade name: PEBAX7233SA01; manufactured by elf atchem). did.

  The stent was prepared by cutting a SUS316L tube (inner diameter 1.80 mm, outer diameter 2.05 mm) into a desired pattern by laser processing and then electrolytic polishing.

  After joining the outer tube and the balloon by heat welding, the inner tube was inserted into the tube and arranged in a coaxial double tube with the outer tube. At this time, the tip of the inner tube passed through the inside of the balloon, and the balloon and the inner tube were joined by heat welding at the balloon tip side sleeve portion. In joining, a core material of an arbitrary size coated with a highly lubricious material such as molded polytetrafluoroethylene was appropriately used to secure an inflation lumen or a guide wire lumen. A hub was bonded to the rear end side of the outer tube to create a delivery catheter.

  The stent movement prevention mechanism was prepared by heating using a pellet of polyamide elastomer (trade name: PEBAX2533SA01; manufactured by elf Atochem) and then rolling with a press machine to form a thin film (film thickness: 30 μm). Further, three pieces of this film having a length of 18 mm and a width of 1.5 mm were cut out and used as a constituent material of the stent movement prevention mechanism.

  While decompressing the delivery catheter, the balloon was folded into a triset shape (shape that folds the balloon into three blades), and the balloon was folded by applying urethane adhesive to the front and rear ends of the stent movement prevention mechanism. In the state, they were adhered to the three blades on the outside in a direction coinciding with the catheter axial direction. Furthermore, the stent was folded and placed thereon, and was crimped onto the surface of the stent movement prevention mechanism. The configuration of the stent movement prevention mechanism obtained by Example 1 is the same as the configuration illustrated in FIGS. 7 and 12.

(Comparative Example 1)
A delivery catheter was prepared in the same manner as in Example 1, and the balloon was folded in a triset, and then the stent was folded thereon. Comparative Example 1 does not have a stent movement prevention mechanism.

(Evaluation of trackability performance by simulated blood vessel plate)
The operability of inserting each sample (Example 1 and Comparative Example 1) into a simulated blood vessel was evaluated. For evaluation, a guide catheter (Launcher: 6Fr, JL3.5, manufactured by Medtronic), a hemostack valve, and a guide wire (Neo's Intermediate: manufactured by Asahi Intec Co., Ltd.) are placed in 37 ° C water, and the guide catheter is used as a simulated blood vessel. A system that was inserted into the plate and circulated water inside the guide catheter, hemostack valve, and plate was used. A sample was inserted from the inlet of the hemostack valve, the hand of the sample was chucked to a load meter, and the resistance value when passing through the plate was measured with the load meter.

(Evaluation of dropout strength of stent movement prevention mechanism)
While holding the rear end portion of the stent of each sample produced, the sample was pulled to the proximal side by a tensile tester, and the strength when the stent was moved or dropped was measured. For example, when the stent moved and then dropped, the strength when the stent moved was measured.

  (Evaluation results)

表１に示すように、本発明に係る実施例１と、比較例１において、模擬血管プレート内への通過荷重を比較すると、ステント移動防止機構を有する実施例と有さない比較例１とでは、ほとんど差はないことがわかった。一方、ステント脱落強度においては１Ｎもの差が生じておりステント移動防止機構を有している実施例１の方が強度が高いことが明らかとなった。これらのことからステント移動防止機構が設置されても柔軟性を維持することによってトラッカビリティ性能が劣らず、脱落強度も向上していることが確認できた。

As shown in Table 1, in Example 1 according to the present invention and Comparative Example 1, when comparing the passing load into the simulated blood vessel plate, the Example having the stent movement prevention mechanism and the Comparative Example 1 not having I found that there was almost no difference. On the other hand, in the stent dropout strength, a difference of 1N occurred, and it was revealed that Example 1 having a stent movement prevention mechanism has higher strength. From these facts, it was confirmed that maintaining the flexibility even when the stent movement prevention mechanism is installed, the trackability performance is not inferior and the drop-off strength is also improved.

FIG. 1 is a schematic view of a high-speed exchange type among general balloon catheters. FIG. 2 is a schematic view of an over-the-wire type of a general balloon catheter. FIG. 3 is a schematic view of a balloon of a stent delivery catheter according to an embodiment of the present invention. FIG. 4 is an example of a view in which a stent movement prevention mechanism according to the embodiment is arranged on a balloon and a view seen from the rear end side. FIG. 5 is an example in which the stent movement prevention mechanism according to the embodiment is arranged on a balloon. Each of FIGS. 6A, 6B, and 6C is an example in which the stent movement prevention mechanism according to the embodiment is arranged on a balloon. FIG. 7 is an example in which the stent movement prevention mechanism according to the embodiment is arranged on a balloon. FIG. 8 is an example of a view in which a stent movement prevention mechanism according to the embodiment is arranged on a balloon and a view from the rear end side. FIG. 9 is an example of a view in which the stent movement prevention mechanism according to the embodiment is arranged on a balloon and a view from the rear end side. FIG. 10 is an example of a view in which the stent movement prevention mechanism according to the embodiment is arranged on a balloon and a view seen from the rear end side. FIG. 11 is an example of a view in which a stent movement prevention mechanism according to the embodiment is arranged on a balloon and a view seen from the rear end side. Each of FIG. 12A and FIG. 12B is an example of a cross-sectional view in which the stent movement prevention mechanism according to the embodiment is arranged on a balloon. Each of FIGS. 13A, 13B, 13C, and 13D is an example of a view in which the stent movement prevention mechanism according to the embodiment is arranged on a balloon and a view seen from the rear end side. 14A, 14B, 14C, and 14D are examples of the stent movement preventing mechanism according to the embodiment arranged on the balloon and the view seen from the rear end side.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Balloon 2 Balloon straight pipe part 3 Balloon taper part 3a Front end side taper part 3b Rear end side taper part 4 Balloon sleeve part 4a Front end side sleeve part 4b Rear end side sleeve part 5 Stent 6 Stent movement prevention mechanism 7 Inner tube 8 Outer tube 9 Hub

Claims (14)

A balloon for a stent delivery catheter connected to a stent delivery catheter, wherein the balloon includes a straight tube portion, a tapered portion at least at one end of the straight tube portion, and a sleeve at an end portion of the tapered portion. And
The balloon is further provided with a stent movement prevention mechanism on at least a part of the surface of each part,
A balloon for a stent delivery catheter.   The balloon according to claim 1, wherein at least a part of the stent movement prevention mechanism is fixed to the balloon.   The stent movement prevention mechanism has a distal end portion and a rear end portion extending in a longitudinal direction that coincides with the catheter axial direction, and at least a part of the distal end portion is either a sleeve portion or a tapered portion on the distal end side of the balloon. 2. The balloon according to claim 1, wherein the rear end portion is fixed to one of a sleeve portion and a tapered portion on the rear end side of the balloon and is not fixed to a straight tube portion of the balloon.   The stent movement prevention mechanism has a distal end portion and a rear end portion extending in a longitudinal direction coinciding with the catheter axial direction, and the distal end portion is fixed to a sleeve portion or a tapered portion on the distal end side of the balloon, and the rear end portion 2. The balloon according to claim 1, wherein the portion exists on the straight tube portion of the balloon or on the tapered portion or the sleeve portion on the rear end side, but is not fixed.   The stent movement prevention mechanism has a distal end portion and a rear end portion extending in a longitudinal direction coinciding with a catheter axial direction, and the rear end portion is fixed to a sleeve portion or a taper portion on the rear end side of the balloon, 2. The balloon according to claim 1, wherein the portion exists on the straight tube portion of the balloon or on the tapered portion or the sleeve portion on the distal end side, but is not fixed.   The said balloon is folded centering on the said catheter axial direction, The said stent movement prevention mechanism is fixed to at least one part of the site | part equivalent to the outer side of the folded balloon. Balloon as described in.   3. The balloon according to claim 1, wherein the balloon is folded about the axial direction of the catheter, and the stent movement prevention mechanism is fixed at least partially at a portion corresponding to the inside of the folded balloon. Balloon as described in.   The balloon according to any one of claims 1 to 7, wherein a longitudinal direction of the stent movement prevention mechanism coincides with the catheter axial direction.   The balloon according to any one of claims 1, 2, 6, and 7, wherein a longitudinal direction of the stent movement preventing mechanism coincides with a circumferential direction of the catheter.   The balloon according to any one of claims 1 to 8, wherein the stent movement prevention mechanism is made of resin.   The balloon according to claim 10, wherein the Shore D hardness of the resin is equal to or lower than the Shore D hardness of the balloon.   The balloon according to claim 10, wherein the stent movement prevention mechanism is a film.   The balloon with a stent according to any one of claims 1 to 12, wherein the stent is fixed via the stent movement prevention mechanism. A stent delivery catheter comprising the balloon according to any one of claims 1 to 12 or the balloon with a stent according to claim 13.

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