JP2018050733A - Balloon catheter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a balloon catheter capable of performing both predilation and discharge of medicine with one-time insertion of the catheter, and preventing medicine from dropping during delivery.SOLUTION: There is provided a balloon catheter 1 having a balloon 11 at the tip of a long-sized shaft 10. A thin film-like cover body 13 is provided on the surface of the balloon 11, and the cover body 13 is connected to a long-sized body extending to a base end side. Also, the cover body 13 is provided so as to cover the outside of the folded balloon 11, and expands accompanying the expansion of the balloon 11.SELECTED DRAWING: Figure 8

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

  In the treatment using the balloon catheter, before the drug is released to the lesioned part, pre-dilation is performed in which the lesioned part is expanded in advance. For this reason, a normal balloon that does not have a drug is delivered to the lesion, and pre-dilatation is performed. After removing the catheter having the balloon, a catheter having a drug application balloon is inserted, and the drug is released at the lesion. It was necessary to insert a different type of catheter twice.

  The present invention has been made in order to solve the above-described problems. A balloon catheter that can perform both pre-expansion and drug release with a single insertion of the catheter, and prevents drug dropout during delivery. The purpose is to provide.

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,
A thin film cover body is provided on the surface of the balloon,
The said cover body is connected with the elongate body extended in the base end side.

  The balloon catheter configured as described above can prevent the dropout of the drug because the surface of the balloon is not exposed in the living body lumen at the time of balloon delivery and pre-expansion. Also, it is possible to perform both pre-expansion and expansion for drug release by expanding the balloon in a state where the cover body is provided, collecting the cover body with a long body, and then expanding the balloon again. it can.

  The cover body is provided so as to cover the outside of the folded balloon, and extends as the balloon is expanded. For this reason, the cover body can be expanded following the expansion of the balloon, and the pre-expansion can be surely performed.

  The balloon includes a proximal tapered portion that expands from the proximal end toward the distal end, a straight portion having the same diameter along the axial direction, and a distal tapered portion that decreases in diameter from the proximal end toward the distal end. The cover body covers at least the surface of the straight portion of the balloon. For this reason, the area | region in which a chemical | medical agent is provided can be reliably covered with a cover body, and the drop-out of a chemical | medical agent can be prevented.

  The long body is formed of a thin wire, and the distal end portion reaches a portion of the cover body that covers the balloon. Thereby, the wire suppresses overexpansion of the cover body, and the cover body and the balloon can be appropriately expanded in the pre-expansion.

  If a plurality of the long bodies are provided in the circumferential direction over substantially the entire length of the cover body, the overexpansion of the cover body can be more effectively suppressed by the wire.

  If the cover body covers the surface of the balloon and is folded together with the balloon, the cover body can be expanded together with the balloon because the cover body has the same level of extensibility as the balloon.

  The surface of the cover body is coated with a hydrophilic coating. For this reason, it is possible to improve the lubricity of the distal end portion of the balloon catheter without affecting the surface of the balloon and to facilitate insertion into the living body lumen.

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 cover body. It is sectional drawing which cut | disconnected the balloon covered by the cover body by the plane orthogonal to an axial direction. It is sectional drawing of the state which expanded the balloon covered with the cover body. It is sectional drawing of the state which has arrange | positioned the balloon covered with the cover body in the constriction part of the blood vessel. It is sectional drawing of the state which expanded the balloon from the state of FIG. FIG. 8 is a cross-sectional view of the state in which the balloon is deflated from the state of FIG. 7 and the cover body is started to be pulled by the wire. It is sectional drawing of the state which expanded the balloon again after collection | recovery of a cover body. It is sectional drawing which cut | disconnected the balloon covered with the cover body of the 2nd form by the plane orthogonal to an axial direction.

  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. The balloon 11 in a state before expansion is covered with a thin film cover body 13. A long wire 14 is connected to the cover 13, and the wire 14 extends to the proximal portion of the balloon catheter 1.

  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. The hollow interior of the inner tube 21 forms a guide wire lumen 23 through which the guide wire 2 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.

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 cover body 13 covers the proximal end tapered portion 30 and 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.

  As shown in FIG. 3, the cover body 13 includes a base end cover portion 13 a that covers the base end tapered portion 30 of the balloon 11 and a straight cover portion 13 b that covers the straight portion 31 of the balloon 11. As a material of the cover body 13, a paraffin film that can be extended by a tensile force can be used. The material of the cover body 13 may be any other material as long as it is a thin film-like member that can be extended by a tensile force. Thereby, the cover body 13 can be expanded so that the diameter increases as the folded balloon 11 expands. Further, the surface of the cover body 13 is coated with a hydrophilic coating, so that the lubricity when the balloon catheter 1 is inserted into the living body lumen can be improved.

  The wire 14 connected to the cover body 13 extends over substantially the entire length from the proximal end portion to the distal end portion of the cover body 13. Further, the wire 14 branches into a plurality of pieces in the cover body 13, and a plurality of wires 14 are arranged in the circumferential direction of the cover body 13. The wire 14 is formed of a metal such as stainless steel, and has an action of suppressing overexpansion with respect to the cover body 13 that expands as the balloon 11 expands. Since the cover body 13 is formed of a highly flexible material, it has high compliance and may cause overexpansion with respect to the expansion pressure, but the wire 14 suppresses it.

  As shown in FIG. 4, the balloon 11 is folded so as to have a plurality of blade portions 33 along the circumferential direction. The cover body 13 covers the surface of the blade portion 33 of the balloon 11 and the surface of the other region. Further, the wire 14 is provided along the surface of the cover body 13.

  As shown in FIG. 5, when the balloon 11 is expanded with the cover body 13 attached, the balloon 11 expands from a folded state to a circular cross section. Along with this, the cover body 13 attached to the surface of the balloon 11 is also expanded. The cover body 13 expands due to the expansion pressure, but does not contract. Therefore, when the balloon 11 is contracted from the state of FIG. 5, it remains in the expanded state. After the balloon 11 is deflated, the cover body 13 can be collected by pulling the wire 14 extending to the proximal portion toward the proximal end side.

  Next, a treatment method using the balloon catheter 1 will be described. First, a blood vessel 40 is percutaneously punctured with a catheter introducer (not shown) by the Seldinger method or the like. Next, a guiding catheter (not shown) into which the guide wire 2 is inserted is inserted into the catheter introducer, the guide wire 2 is protruded from the distal end, and the distal end of the guiding catheter is then inserted into the blood vessel from the distal opening of the catheter introducer. Insert into 40. Thereafter, the guiding catheter is gradually advanced to the target site while the guide wire 2 is advanced.

  Next, the end of the guide wire 2 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 2 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 40 from the tip, the balloon catheter 1 is pushed along the guide wire 2, and the tip portion including the balloon 11 of the balloon catheter 1 is The balloon 11 is positioned in the target stenosis by protruding from the distal end of the guiding catheter. This state is shown in FIG. In the process of inserting the balloon catheter 1, the balloon 11 having the drug on the surface is covered with the cover body 13 and is not exposed to the living body lumen, so that the drug can be prevented from falling off.

  When the balloon 11 is placed in the stenosis, the balloon 11 is first pre-expanded. When the expansion fluid is supplied into the balloon 11 from the first opening 12a of the hub 12 via the expansion lumen 22, the folded balloon 11 expands so as to spread radially outward. Along with this, the cover body 13 also expands and presses against the inner surface of the narrowed portion. Thereby, the balloon 11 having the cover body 13 pushes and expands the narrowed portion of the blood vessel 40. This state is shown in FIG. Also in the pre-expansion of the balloon 11, since the surface of the balloon 11 is covered with the cover body 13, it is possible to prevent the drug from transferring to the living body in the pre-expansion stage.

  When the balloon 11 is pre-expanded, the expansion fluid is discharged from the balloon 11 through the expansion lumen 22 and the first opening 12a, and the balloon 11 is temporarily deflated. As described above, the cover body 13 can be extended but does not contract, and therefore remains in an expanded state. When the balloon 11 is deflated, the wire 14 is pulled from the hand to the proximal end side, and the cover body 13 is recovered. At this time, the balloon 11 is left in the stenosis portion as it is. This state is shown in FIG.

  When the cover body 13 is collected, the surface of the balloon 11 having the drug is exposed in the living body lumen. In this state, as shown in FIG. 9, the balloon 11 is expanded again. Thereby, the medicine on the surface of the balloon 11 is transferred to the living body while the balloon 11 expands the narrowed portion.

  Thereafter, the expansion fluid is discharged from the balloon 11, the balloon 11 is deflated, and the balloon catheter 1 is removed from the living body. When the balloon catheter 1 is removed, the guide wire 2 is also removed. In addition, when performing another treatment continuously, the guide wire 2 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.

  As described above, the treatment method in the present embodiment has the balloon 11 at the distal end portion, the surface of the balloon 11 is provided with the medicine, and the balloon 11 is covered with the thin film cover body 13. The body 13 is a treatment method for inserting a balloon catheter 1 connected to a long body extending proximally into a lesion in a living body lumen, and delivering a balloon 11 covered with a cover body 13 to the lesion. And the step of pre-expansion in which the balloon 11 is expanded while being covered with the cover body 13 at the lesioned part, and the balloon 11 is indwelled by pulling the elongated body toward the proximal end side after the balloon 11 is deflated. The step of collecting the cover body as it is and the step of expanding the balloon 11 again to transfer the surface medicine to the living body. As a result, when the balloon 11 is inserted into the living body lumen, the balloon 11 is covered with the cover body 13, so that the surface of the balloon 11 is not exposed to the living body lumen. For this reason, even if the medicine is provided on the surface of the balloon 11, it can be prevented from falling off. Further, since the pre-expansion can be performed in a state where the balloon 11 is covered with the cover body 13, both the pre-expansion and the expansion for transferring the drug can be performed with one catheter, thereby reducing the man-hour of the procedure. Can save time.

  In this embodiment, the cover body 13 is provided so as to cover the balloon 11 in a folded state. However, as shown in FIG. 10, the balloon 11 may be folded in a state covered with the cover body 13. . In this case, the cover body 13 only needs to have the same extensibility as the balloon 11.

  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 a thin film cover body 13 is provided on the surface of the balloon 11. The cover body 13 is connected to an elongated body extending to the base end side. According to the balloon catheter 1, the surface of the balloon 11 is not exposed to the living body lumen when the balloon 11 is delivered and when it is pre-expanded, so that the drug can be prevented from falling off. Further, the balloon 11 is pre-expanded with the cover body 13 provided, and the balloon 11 is expanded again after the cover body 13 is collected as a long body, so that both the pre-expansion and the expansion for drug release are performed. It can be performed.

  Further, the cover body 13 is provided so as to cover the outer side of the folded balloon 11, and extends as the balloon 11 is expanded. For this reason, the cover body 13 can be expanded following the expansion of the balloon 11, and the front expansion can be reliably performed.

  The balloon 11 also has a proximal tapered portion 30 that expands from the proximal end toward the distal end, a straight portion 31 having the same diameter along the axial direction, and a diameter that decreases from the proximal end toward the distal end. The cover body 13 covers at least the surface of the straight portion 31 of the balloon 11. For this reason, the area | region in which a chemical | medical agent is provided can be reliably covered with the cover body 13, and omission of a chemical | medical agent can be prevented.

  Further, the long body is formed by a thin wire 14, and the distal end portion reaches a portion covering the balloon 11 of the cover body 13. Thereby, the wire 14 can suppress the overexpansion of the cover body 13, and can expand the cover body 13 and the balloon 11 appropriately in the front expansion.

  Further, if a plurality of long bodies are provided in the circumferential direction over substantially the entire length of the cover body 13, the overexpansion of the cover body 13 can be more effectively suppressed by the wire 14.

  Further, if the cover body 13 covers the surface of the balloon 11 and is folded together with the balloon 11, the cover body 13 can be expanded together with the balloon 11 because the cover body 13 has the same level of extensibility as the balloon 11. .

  The surface of the cover body 13 is hydrophilic coated. For this reason, without affecting the surface of the balloon 11, it is possible to improve the lubricity of the distal end portion of the balloon catheter 1 and facilitate insertion into the living body lumen.

  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, in the above-described embodiment, the wire 14 is provided up to the distal end portion of the cover body 13, but the wire 14 may be fixed to the proximal end portion of the cover body 13 and does not reach the surface of the balloon 11. May be. Even when the wires 14 reach the surface of the balloon 11, the number and the tip positions of the wires 14 in the circumferential direction of the balloon 11 can be set arbitrarily.

  In the above-described embodiment, the cover body 13 covers the proximal end taper portion 30 and the straight portion 31 of the balloon 11, but the cover body 13 may cover at least a region of the balloon 11 where the medicine is provided. Good.

DESCRIPTION OF SYMBOLS 1 Balloon catheter 2 Guide wire 10 Shaft 11 Balloon 12 Hub 13 Cover body 14 Wire 15 Cover body 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

Claims (7)

A balloon catheter having a balloon at the tip of a long shaft,
A thin film cover body is provided on the surface of the balloon,
The said cover body is a balloon catheter connected with the elongate body extended in the base end side.   The balloon catheter according to claim 1, wherein the cover body is provided so as to cover an outer side of the folded balloon, and extends as the balloon is expanded. The balloon includes a proximal tapered portion that expands from the proximal end toward the distal end, a straight portion having the same diameter along the axial direction, and a distal tapered portion that decreases in diameter from the proximal end toward the distal end. Have
The balloon catheter according to claim 1, wherein the cover body covers at least a surface of the straight portion of the balloon.   The balloon catheter according to any one of claims 1 to 3, wherein the elongated body is formed of a thin wire, and a distal end portion reaches a portion of the cover body that covers the balloon.   The balloon catheter according to claim 4, wherein a plurality of the elongated bodies are provided in a circumferential direction over substantially the entire length of the cover body.   The balloon catheter according to claim 1, wherein the cover body covers a surface of the balloon and is folded together with the balloon.   The balloon catheter according to any one of claims 1 to 6, wherein a surface of the cover body is coated with a hydrophilic coating.

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