JP2018075163A - Balloon catheter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a balloon catheter having a protector that allows a balloon to be inflated while covering the balloon, and works so that the balloon contracted after being inflated can be restored to an original shape easily.SOLUTION: A balloon catheter 1 having a balloon 11 at the tip of a long shaft 10 includes a protector 41 that can be moved along an axial direction of the shaft 10. The protector 41 includes a plurality of linear parts 41a that surround the balloon 11 from outside, and can be expanded and contracted.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a balloon catheter having a balloon at the tip of a long shaft.

  A balloon catheter is widely used as a medical device for improving a lesion (stenosis) occurring in a living body lumen. A balloon catheter usually includes a long shaft and a balloon that is provided on the distal end side of the shaft and is radially expandable. The balloon that is deflated is passed through a thin biological lumen into the body. The lesion can be expanded by expanding after reaching the target location.

  On the other hand, if the lesioned part is forcibly expanded by a balloon, the endothelial cells may proliferate excessively and may cause new stenosis (restenosis) in the lesioned part. For this reason, a drug coated balloon (DCB) in which a drug for suppressing stenosis is coated on the outer surface of the balloon may be used. By expanding the drug application balloon, the drug coated on the outer surface can be released to the lesion, and the drug can be transferred to the living tissue, thereby suppressing restenosis.

  In a medical device having a substance such as a drug on the surface, it is necessary to prevent the substance on the surface from dropping off until the medical device is delivered to the lesion. For example, in Patent Document 1, a protective sleeve that covers the outer peripheral side of the balloon is provided in order to prevent the medicine on the surface of the balloon from falling off in vivo.

JP 2013-223664 A

  When a protective body such as a protective sleeve that protects the balloon is provided, a procedure is adopted in which the balloon is delivered to the lesion, and then the protective body is removed and the balloon is expanded. Since the situation of a lesion part is various, it may arise when it is appropriate to expand a balloon, without performing the procedure which removes a protection body. However, with a protector like Patent Document 1, the balloon cannot be expanded while the balloon is covered.

  In addition, the balloon is delivered to the lesion in a folded state. After the balloon is expanded, it is desirable that when the balloon is deflated and retrieved, the balloon returns to its original folded shape.

  The present invention has been made in order to solve the above-described problems. The balloon has a protective body that can expand the balloon while covering the balloon, and that can easily restore the balloon deflated after expansion to its original shape. An object is to provide a catheter.

A balloon catheter according to the present invention that achieves the above object is a balloon catheter having a balloon at the end of a long shaft,
It has a protector which can move along the axial direction of the shaft, and this protector has a plurality of linear parts which surround the balloon from the outside and can be expanded and contracted.

  The balloon catheter configured as described above can prevent contact of the balloon with the inner wall surface of the blood vessel when the balloon advances in the blood vessel by covering the balloon with a linear portion, and the drug provided on the surface of the balloon. Dropout can be suppressed. Further, even when the balloon is covered with a protective body, the balloon can be expanded to transfer the medicine to the living body, and the degree of freedom of the procedure can be increased.

  Further, a protective shaft is provided on the outer peripheral side of the shaft, and the protective body is provided at the tip of the protective shaft. As a result, the protector can be slid by the operator.

  Moreover, the said protection body has an opening part which can pass the said balloon in the front-end | tip part. Thereby, a protector can be moved to a base end side from a balloon, and it can be made easy to expose a balloon from a protector.

  Further, if the balloon has a plurality of wings in a folded state, and the protector has the same number of the linear parts as the wings, the linear parts can be removed when the balloon is collected. It can be made to contact | abut between blade | wing parts, and it can make it easy to return a balloon to the shape which has the original blade | wing part.

  Moreover, the said linear part has a shape where the axial direction center part swelled. Thereby, the balloon which has the shape where the axial direction center part swelled can be easily accommodated in a protector.

  Moreover, the front-end | tip part of the said linear part is mutually contacting with the front-end | tip part of another linear part, and the front-end | tip part of the said linear part separates by extending the said protective body, The said protective body It is also possible to open the front end of the. According to this, at the time of insertion of the balloon catheter, it is possible to open the distal end portion largely by expanding the protective body while reducing the diameter of the distal end portion of the protective body to improve the passage through the blood vessel. The balloon can be easily collected.

It is a front view of a balloon catheter. It is an expanded sectional view near the front-end | tip part of a balloon catheter. It is a front view of a protector. It is an enlarged front view of the balloon vicinity covered with the protector. It is an enlarged front view of the vicinity of the balloon in a state where the balloon is exposed by sliding the protector. It is sectional drawing which cut | disconnected the balloon by the plane orthogonal to an axial direction. It is sectional drawing of the deflated balloon stored in the inside of a protector. FIG. 5 is an enlarged front view of the vicinity of the balloon in a state where the balloon is expanded while being accommodated in a protective body. It is a front view of the protection body of the 2nd form. It is an enlarged front view of the balloon vicinity covered with the protection body of the 2nd form. It is an enlarged front view of the balloon vicinity pre-expanded in the state covered with the protection body of the 2nd form. It is an enlarged front view of the balloon vicinity in the state which made the slide of the protection body of a 2nd form expose the balloon. It is an enlarged front view of the balloon vicinity in the state which draws in the contracted balloon to the protection body of a 2nd form.

  Embodiments of the present invention will be described below with reference to the drawings. In addition, the dimension ratio of drawing is exaggerated on account of description, and may differ from an actual ratio. Further, in this specification, the side of the catheter that is inserted into the living body lumen is referred to as the “distal end” or “distal end side”, and the proximal side for operation is referred to as “proximal end” or “proximal end side”.

  The balloon catheter 1 of the present embodiment is a device for percutaneously inserting into a living body lumen and expanding and improving a lesioned part (stenosis part) generated in the living body lumen. As shown in FIG. 1, the balloon catheter 1 includes a long shaft 10, a balloon 11 provided at the distal end portion of the shaft 10, and a hub 12 provided at the proximal end portion of the shaft 10.

  As shown in FIG. 2, the shaft 10 includes an outer tube 20 and an inner tube 21 that are each formed in a long hollow shape and are arranged concentrically. The inner diameter of the outer tube 20 is larger than the outer diameter of the inner tube 21, and the inner tube 21 is accommodated in the hollow interior of the outer tube 20. A hollow interior of the inner tube 21 forms a guide wire lumen 23 through which a guide wire (not shown) is inserted. Further, an expansion lumen 22 through which the expansion fluid of the balloon 11 is circulated is formed inside the hollow of the outer tube 20 and outside the inner tube 21. In FIG. 2, the protective body 41 and the protective shaft 40 are omitted.

The inner tube 21 protrudes further to the distal end side than the distal end of the outer tube 20. The balloon 11 has a proximal end portion fixed to the distal end portion of the outer tube 20, and a distal end portion fixed to the distal end portion of the inner tube 21. Thereby, the inside of the balloon 11 communicates with the expansion lumen 22. The balloon 11 is expanded by injecting an expansion fluid through the expansion lumen 22. The expansion fluid may be a gas or a liquid. For example, a gas such as helium gas, CO ₂ gas, or O ₂ gas, or a liquid such as physiological saline or a contrast agent can be used.

  The outer tube 20 and the inner tube 21 are preferably formed of a material having a certain degree of flexibility. Examples of such a material include polyolefins such as polyethylene, polypropylene, polybutene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, ionomer, or a mixture of two or more thereof, soft polyvinyl chloride resin, Examples thereof include fluororesins such as polyamide, polyamide elastomer, polyester, polyester elastomer, polyurethane, polytetrafluoroethylene, silicone rubber, and latex rubber. The balloon 11 is formed of a flexible material like the outer tube 20 and the inner tube 21.

  The balloon 11 includes a proximal tapered portion 30 that expands from the proximal end toward the distal end, a straight portion 31 that has the same diameter along the axial direction, and a distal tapered that decreases in diameter from the proximal end toward the distal end. Part 32. A drug is provided on the surface of at least the straight portion 31 of the balloon 11.

  The hub 12 has a first opening 12 a that functions as a port through which the expansion fluid 22 flows in and communicates with the expansion lumen 22 of the outer tube 20, and a second opening 12 b that communicates with the guide wire lumen 23. . In addition, two protrusions 12 c are provided on the outer peripheral surface of the hub 12 so that the operator can easily apply a rotational force. The material of the hub 12 is not particularly limited. For example, a hard resin such as polycarbonate, polyethylene, or polypropylene can be used.

  A protective shaft 40 that is slidable along the axial direction of the shaft 10 is provided outside the shaft 10. A protective body 41 that surrounds the balloon 11 from the outside is provided at the tip of the protective shaft 40. In FIG. 1, the protective body 41 covers the balloon 11, but since the protective shaft 40 can slide along the axial direction of the shaft 10, the protective body 41 moves to the proximal end side from the balloon 11, 11 can be exposed outside the protector 41.

  As shown in FIG. 3, the protector 41 has a plurality of linear portions 41a. Moreover, the protection body 41 has the front-end | tip support part 41b which supports the linear part 41a in a front-end | tip part. The linear portion 41 a is formed of a stretchable resin material in a linear shape, and is provided so as to extend from the distal end portion of the protective shaft 40 to the distal end support portion 41 b of the protective body 41. In addition, the linear part 41a may be formed with the metal material. Four linear portions 41 a are provided in the circumferential direction in the protector 41. Moreover, the linear part 41a has the shape where the center part swelled in the axial direction. The tip support part 41b has an opening 41c through which the balloon 11 and the guide wire can be inserted.

  A treatment method using the balloon catheter 1 will be described. First, a blood vessel is punctured percutaneously with a catheter introducer (not shown) by the Seldinger method or the like. Next, a guiding catheter (not shown) with a guide wire inserted is inserted into the catheter introducer, the guide wire is protruded from the distal end, and then the distal end of the guiding catheter is inserted into the blood vessel from the distal opening of the catheter introducer. insert. Thereafter, the guiding catheter is gradually pushed to the target site while the guide wire is advanced.

  Next, the distal end of the guide wire is inserted into the distal end opening of the guide wire lumen 23 of the balloon catheter 1 in a state where the balloon 11 is deflated, and the guide wire is taken out from the second opening 12 b of the hub 12. Next, the balloon catheter 1 is inserted into the guiding catheter inserted into the blood vessel from the tip, and the balloon catheter 1 is pushed along the guide wire.

  When the balloon catheter 1 is inserted into the blood vessel, the balloon 11 is covered with a protective body 41 as shown in FIG. Since the linear portion 41a of the protector 41 is located on the outer peripheral side from the surface of the balloon 11, the contact of the balloon 11 with the inner wall surface of the blood vessel can be suppressed when the balloon 11 advances in the blood vessel. Thereby, dropping of the medicine provided on the surface of the balloon 11 can be suppressed.

  The balloon catheter 1 is inserted until the distal end portion including the balloon 11 protrudes from the distal end of the guiding catheter until the balloon 11 is positioned in the target stenosis. When the balloon 11 is inserted to the target position, as shown in FIG. 5, the protection shaft 40 is slid to the proximal end side, and the protection body 41 is moved to the proximal end side from the balloon 11. Thereby, the balloon 11 is located outside the protector 41. In this state, the expansion fluid is supplied into the balloon 11 from the first opening 12a of the hub 12 through the expansion lumen 22, and the balloon 11 is expanded. Thereby, the medicine on the surface of the balloon 11 can be transferred to the living body while the balloon 11 expands the narrowed portion.

  Thereafter, the expansion fluid is discharged from the balloon 11 to deflate the balloon 11. As shown in FIG. 6, the balloon 11 before expansion is folded along the peripheral surface of the outer tube 20 so that the outer diameter becomes as small as possible. In the present embodiment, the balloon 11 is folded so as to have four blade portions 33, and each blade portion 33 is laid down along the peripheral surface of the outer tube 20. Even after the balloon 11 is expanded and contracted, it is desirable that the balloon 11 returns to the folded shape as shown in FIG.

  The deflated balloon 11 is drawn to the proximal end side and stored inside the protector 41. As shown in FIG. 7, the linear portion 41 a of the protection body 41 abuts on the surface of the balloon 11 accommodated in the protection body 41. Four linear portions 41 a are provided in the circumferential direction, and each of the linear portions 41 a can come into contact with an intermediate position of a region that becomes the blade portion 33 on the surface of the balloon 11. Of the surface of the balloon 11, the position where the linear portion 41a abuts becomes a starting point at which the balloon 11 is folded again, and the four blade portions 33 can be easily formed as before expansion. Thereby, the outer diameter of the balloon 11 after contraction becomes small, and the recovery of the balloon catheter 1 can be facilitated.

  When the balloon 11 is deflated and accommodated in the protective body 41 and the balloon 11 is folded, the balloon catheter 1 is removed from the living body. When the balloon catheter 1 is removed, the guide wire is also removed. In addition, when performing another treatment continuously, the guide wire may be left. When the balloon catheter 1 is removed, the guiding catheter is removed from the catheter introducer, and the catheter introducer is also removed from the living body to complete the procedure.

  Further, the balloon 11 can be expanded as follows. The procedure is the same as the above-described treatment method until the balloon 11 is disposed in the target constriction. Here, without moving the protection body 41 to the proximal end side, the balloon 11 is expanded while being accommodated in the protection body 41 as shown in FIG. The protector 41 covers the balloon 11 with a plurality of linear portions 41a, and the linear portions 41a have elasticity. For this reason, when the balloon 11 is expanded, the linear portion 41a is expanded by the expansion force of the balloon 11, and the surface of the balloon 11 is exposed outward from the gap between the linear portions 41a. As described above, the balloon 11 and the linear portion 41a are integrally expanded, whereby the balloon 11 can expand the narrowed portion of the blood vessel and transfer the medicine on the surface of the balloon 11 to the living body.

  Thus, since the protection body 41 is formed by the plurality of linear portions 41a having elasticity, the balloon 11 can be expanded even when the balloon 11 is covered with the protection body 41, and the procedure is free. The degree can be increased. In addition, since the number of the linear portions 41 a matches the number of the blade portions 33 of the balloon 11, the balloon 11 can be easily returned to the original shape by the linear portions 41 a when the balloon 11 is collected.

  After the balloon 11 is expanded as shown in FIG. 8, the expansion fluid is discharged from the balloon 11 and the balloon 11 is deflated. At this time, the blade portion 33 is reliably formed by the linear portion 41 a of the protector 41. Thereafter, the protector 41 and the balloon 11 are both removed from the living body.

  Next, the protection body 42 according to the second embodiment will be described. As shown in FIG. 9, the protection body 42 of this embodiment is formed by a plurality of linear portions 42 a provided at the tip of the protection shaft 40. The linear part 42a has extensibility. The front end portion of the linear portion 42a is in contact with the other linear portions 42a and forms a streamline shape as a whole. For this reason, the diameter of the front-end | tip part of the protection body 42 is small. The linear portions 42 a forming the protection body 42 are not fixed to each other, and a guide wire or the balloon 11 can be inserted into the distal end portion of the protection body 42.

  As shown in FIG. 10, the point that the balloon 11 is protected by the linear portion 42a of the protector 42 is the same as that of the protector 41 of the above-described form. In this way, the balloon 11 is inserted into the blood vessel while being covered with the protector 42. At this time, since the diameter of the distal end portion of the protection body 42 is reduced due to the gathering of the plurality of linear portions 42a, the passage in the blood vessel can be improved.

  As shown in FIG. 11, when the balloon 11 reaches the target site, pre-expansion is performed to expand the balloon 11 to some extent while being covered with the protective body 42. As the balloon 11 is expanded, the protector 42 is also expanded so that its diameter increases. Since the tip portion of the linear portion 42a of the protector 42 is not fixed, the protector 42 is pushed apart and separated from each other, and the tip portion is greatly opened. The opening diameter is preferably larger than the inner diameter of the protective shaft 40.

  After pre-expansion, the balloon 11 is temporarily deflated. When the balloon 11 is deflated, the protection shaft 40 is slid to the proximal end side, and the protection body 42 is moved to the proximal end side from the balloon 11. At this time, the protector 42 is expanded and the tip portion remains open. Then, as shown in FIG. 12, the balloon 11 is expanded, and the medicine on the surface of the balloon 11 is transferred to the living body.

  When the balloon 11 is deflated, the balloon 11 is pulled to the proximal end side and housed in the protective body 42. At this time, the distal end portion of the protective body 42 is greatly opened, so that the deflated balloon 11 can be easily removed. It can be pulled into the protector 42. Further, the balloon 11 can be further pulled to the proximal end side and pulled into the protective shaft 40 to be collected.

  As described above, the balloon catheter 1 according to the present embodiment is the balloon catheter 1 having the balloon 11 at the distal end portion of the long shaft 10, and includes the protector 41 that can move along the axial direction of the shaft 10. The protection body 41 has a plurality of linear portions 41 a that surround the balloon 11 from the outside and can be expanded and contracted. Thus, by covering the balloon 11 with the linear portion 41a, when the balloon 11 advances in the blood vessel, the contact of the balloon 11 with the inner wall surface of the blood vessel can be suppressed, and the medicine provided on the surface of the balloon 11 is prevented from falling off. Can be suppressed. In addition, even when the balloon 11 is covered with the protector 41, the balloon 11 can be expanded to transfer the medicine to the living body, and the degree of freedom of the procedure can be increased.

  Further, a protective shaft 40 is provided on the outer peripheral side of the shaft 10, and a protective body 41 is provided at the tip of the protective shaft 40. Thereby, the protector 41 can be slid by the operator's hand.

  The protector 41 has an opening 41c through which the balloon 11 can pass at the tip. Thereby, the protection body 41 can be moved from the balloon 11 to the proximal end side, and the balloon 11 can be easily exposed from the protection body 41.

  In addition, the balloon 11 has a plurality of blade portions 33 in a folded state, and the protector 41 has the same number of linear portions 41a as the blade portions 33. It is possible to make the balloon 11 return to the shape having the original blade portion 33 by bringing the portion 41 a into contact with the blade portion 33.

  Moreover, the linear part 41a has the shape where the axial direction center part swelled. Thereby, the balloon 11 having a shape in which the central portion in the axial direction is swollen can be easily accommodated in the protector 41.

  Moreover, the front-end | tip part of the linear part 42a is mutually contacting with the front-end | tip part of the other linear part 42a, and the front-end | tip part of the linear part 42a isolate | separates by pushing and spreading the protector 42, and protector The front end portion of 42 can be opened. According to this, when the balloon catheter 1 is inserted, the diameter of the distal end portion of the protective body 42 is reduced to improve the passage through the blood vessel, and the protective body 42 is pushed and widened to widen the distal end portion. The balloon 11 can be easily collected.

  Note that the present invention is not limited to the above-described embodiments, and various modifications can be made by those skilled in the art within the technical idea of the present invention. For example, with respect to the linear portion 41a of the protector 41, in the above-described embodiment, since there are four blade portions 33 of the balloon 11, four correspondingly are provided in the circumferential direction. If the number of sheets is three or five or more, a corresponding number of linear portions are provided.

DESCRIPTION OF SYMBOLS 1 Balloon catheter 10 Shaft 11 Balloon 12 Hub 20 Outer tube 21 Inner tube 22 Expansion lumen 23 Guide wire lumen 30 Base end taper portion 31 Straight portion 32 Tip taper portion 33 Blade portion 40 Protection shaft 41 Protection body 41a Linear portion 41b Tip support Part 41c opening

Claims (6)

A balloon catheter having a balloon at the tip of a long shaft,
The balloon catheter which has a protector which can move along the axial direction of the shaft, and which has a plurality of linear parts which enclose the balloon from the outside and can expand and contract.   The balloon catheter according to claim 1, wherein a protective shaft is provided on an outer peripheral side of the shaft, and the protective body is provided at a distal end portion of the protective shaft.   The balloon catheter according to claim 1, wherein the protective body has an opening through which the balloon can pass at a distal end.   The balloon catheter according to any one of claims 1 to 3, wherein the balloon has a plurality of blade portions in a folded state, and the protective body has the same number of the linear portions as the blade portions. .   The balloon catheter according to any one of claims 1 to 4, wherein the linear portion has a shape in which a central portion in the axial direction swells.   The front end portions of the linear portions are in contact with the front end portions of the other linear portions, and the front end portions of the linear portions are separated from each other by pushing and spreading the protective body. The balloon catheter according to claim 1 or 2, wherein the portion opens.

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