JP2011135989A - Monorail type catheter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a guiding catheter in a new structure, capable of guiding a catheter for treatment by getting closer to a treatment part, reducing the number of proximal end side devices, and thereby shortening a catheter length. <P>SOLUTION: The monorail type catheter 14 to be inserted to a guiding catheter 16 includes: an insertion tube 24 projected from the distal end side opening 64 of the guiding catheter 16 to insert the catheter 18 for treatment; and a wire 26 extended from the proximal end side of the insertion tube 24 and projected from the proximal end side opening 65 of the guiding catheter 16. An extension part 44 to be extended when predetermined tensile force is exerted is provided on the transmission route of the operation force of the monorail type catheter 14. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a monorail type catheter that guides a treatment catheter through insertion, and in particular, is a long monorail type that has a length inserted from a proximal end opening of a guiding catheter and protruding from a distal end opening. It relates to a catheter.

  Conventionally, in percutaneous coronary intervention (PCI), in order to guide a treatment catheter such as a balloon catheter into the coronary artery, a guiding catheter as described in JP-A-9-99088 (Patent Document 1) has been used. It is used.

  For example, in percutaneous coronary angioplasty (PTCA) as one of the PCIs, first, a guide wire for a guiding catheter is inserted into the arterial blood vessel from the wrist or thigh, and then along the guide wire, The guiding catheter is inserted into the arterial blood vessel so that the distal opening of the guiding catheter faces the coronary artery entrance of the heart. Then, only the guide wire for the guiding catheter is removed, and the guide wire of the smaller diameter treatment catheter is made to reach the position passing through the stenosis in the coronary artery through the guiding catheter. Next, a therapeutic catheter such as a balloon catheter is inserted into the coronary artery while extending along the guide wire and extending from the distal opening of the guiding catheter located at the coronary artery entrance, so that the distal end is located in the stenosis. After that, the stenosis is expanded by inflating a balloon provided at the tip.

  By the way, when the distal end portion of the treatment catheter is inserted into the stenosis, the treatment catheter receives a reaction force, and this reaction force is received by the guiding catheter coming into contact with the inner surface of the blood vessel. Yes.

  However, if the stenosis part is away from the coronary artery entrance and the meander is meandering, or if the stenosis part is hard and it is difficult to push the treatment catheter, the reaction force from the treatment catheter can be sufficiently received. In some cases, the distal opening of the guiding catheter may be disengaged from the coronary artery entrance.

  Therefore, in order to obtain a more stable backup by approaching the stenosis, for example, Japanese Patent Application Laid-Open No. 63-238876 (Patent Document 2) discloses a guiding catheter having a double structure of a parent catheter and a child catheter. Proposed. This guiding catheter is inserted into a parent catheter previously inserted into the artery, and a child catheter having a smaller diameter than that of the parent catheter is inserted, and the child catheter is inserted into the coronary artery from the distal end opening of the parent catheter positioned at the coronary artery entrance. By extending, it is possible to approach the vicinity of the constriction.

  However, the guiding catheter described in Patent Document 2 causes an increase in the number of devices because a proximal device such as a Y connector is provided on each of the parent catheter and the child catheter. Furthermore, since the proximal side device of the child catheter protrudes from the proximal side device of the parent catheter, the overall length of the guiding catheter becomes longer. There is also a problem in that the length of the treatment catheter that can be used is restricted.

JP-A-9-99088 JP-A 63-238876

  The present invention has been made in the background of the above-described circumstances, and the solution to the problem is that the treatment catheter can be guided closer to the treatment site and the number of proximal devices can be reduced. Another object of the present invention is to provide a guiding catheter having a novel structure capable of reducing the catheter length.

  That is, the first aspect of the present invention has a length that is inserted from the proximal end side opening of the guiding catheter and protrudes from the distal end side opening, and the treatment catheter is inserted through the length of the treatment catheter. A monorail type catheter that guides the distal end portion to a treatment site, and the monorail type catheter is provided with an insertion tube that protrudes from the distal end side opening of the guiding catheter and into which the treatment catheter is inserted at the distal end portion. In addition, a wire extending from the proximal end side of the insertion tube and protruding from the proximal end side opening of the guiding catheter is connected to the insertion tube, while the wire is connected to the insertion tube through the wire. On the transmission path of the operating force of the monorail catheter to be transmitted, a predetermined wire is attached to the wire. That extension portion which is a stretchable when tension is exerted are provided, characterized.

  If the monorail type catheter structured according to this aspect is used, the monorail type catheter is inserted into the guiding catheter, and the insertion tube of the monorail type catheter is protruded from the distal end side opening of the guiding catheter positioned at the coronary artery entrance. Thus, the insertion tube of the monorail type catheter can be inserted into the coronary artery. And, by using the monorail type catheter as a guiding catheter for the treatment catheter and inserting the treatment catheter through the insertion tube, the insertion tube can guide and support the treatment catheter to a position closer to the treatment site in the coronary artery. You can get better backup power.

  Furthermore, according to the monorail type catheter of the present invention, the insertion tube is provided only at the distal end portion, and is a monorail type in which a wire is provided on the proximal end side from the insertion tube. Therefore, the injection of the chemical solution and the prevention of the backflow of blood are performed using a proximal device of the guiding catheter through which the monorail type catheter is inserted, and the monorail type catheter may be provided with a special proximal side device. It is unnecessary. As a result, the number of proximal side devices can be reduced. At the same time, it is not necessary to insert the treatment catheter into both the proximal device of the guiding catheter and the proximal device of the monorail type catheter inserted therethrough, and the therapeutic catheter is inserted from the proximal device of the guiding catheter. Just enough. As a result, the catheter length required for the therapeutic catheter can be shortened, and more types of therapeutic catheters can be used.

  Further, by configuring a part of the monorail type catheter with a wire, friction with the inner peripheral surface of the guiding catheter is reduced, and the monorail type catheter can be inserted into and removed from the guiding catheter more easily. Further, since the inner clearance of the guiding catheter can be ensured more simply by inserting the wire, the treatment catheter can be inserted and removed more easily.

  By the way, the monorail type catheter of the present invention has a connecting structure of a cylindrical insertion tube and a linear wire, so that the catheter main body has a full length over the entire length as compared with a cylindrical shape, especially when the insertion tube is removed. There is a risk that the connecting portion of the wire is caught on the inner peripheral surface of the guiding catheter. However, according to the present invention, by providing an extension portion that extends when a predetermined tensile force is exerted on the wire, the extension portion is substantially prevented from being pushed into the wire when the monorail catheter is inserted. As a non-deformation, an effective pushing force can be secured. In addition, when the monorail catheter is removed, particularly when the wire is further pulled in a state where the insertion tube is caught, and a predetermined tensile force greater than that exerted during normal removal without being caught is exerted on the wire, By extending the extension part, it is possible to make the operator recognize the occurrence of the catch by the operational feeling. As a result, breakage of the connection portion with the wire or the insertion tube can be prevented, and an excessively large tensile force can be prevented from being applied to the wire, and the connection portion with the wire or the insertion tube caused by excessive pulling can be avoided. Can be prevented from breaking.

  The extension part only needs to be provided on the transmission path of the operation force of the monorail type catheter. The extension part is not limited to the wire, but an operation part such as a hub provided on the proximal end side of the wire, or an insertion tube. May be provided. For example, the extension portion may be formed by extending the proximal end side of the insertion tube in a linear shape so that the insertion tube can be extended, and a wire may be connected to the extension distal end portion of the extension portion. In addition, the wire, the operation unit, and the insertion tube are divided, and the divided part is connected by an extensible member such as a rubber elastic body, a resin spring, or a metal spring so that the extended part can be extended. You may comprise.

  In addition, the extension part in the present invention includes those that simply extend without being restored, but preferably, as the second aspect of the present invention, the extension described in the first aspect is the above extension. The part is an elastic extension part capable of elastic extension. In this way, when the tensile force exerted on the wire is released more than the normal pulling time, the extension portion can be returned to the state before extension. Thereby, for example, when the insertion tube is caught, it is possible to confirm whether or not the catch has been eliminated by repeating the pulling operation, and the recognition effect of the occurrence of the catch due to the extension or the wire breakage can be confirmed. The prevention effect can be obtained repeatedly.

  A third aspect of the present invention is the one described in the first or second aspect, wherein the elongated portion is provided at an end of the wire on the insertion tube side.

  According to this aspect, since the extension portion is positioned in the vicinity of the insertion tube, it is reduced that the extension portion extends due to a cause other than the catch of the insertion tube. As a result, the extension portion can be extended only when the insertion tube is caught, and the occurrence of the catch can be more reliably transmitted to the operator with a feeling of operation.

  According to a fourth aspect of the present invention, in the one according to any one of the first to third aspects, the elongated portion is formed by forming the wire in a wave shape. In this way, there is no need to separately prepare and assemble the extension member, and the extension portion can be formed inexpensively and easily.

  According to a fifth aspect of the present invention, in the one described in any one of the first to fourth aspects, a deformed connecting portion is provided at a tip portion of the wire, and the wire is connected to the connecting portion. It is fixed to the insertion tube. If it does in this way, the adhering force with an insertion tube can be obtained more firmly, and fracture of a wire can be prevented more effectively.

  According to a sixth aspect of the present invention, in the one described in any one of the first to fifth aspects, the insertion tube has a stacked structure of a plurality of tubes, and between the stacked tubes. The tip of the wire is fixed to the insertion tube by sandwiching the tip of the wire and welding both tubes. In this way, since the wire can be fixed to the insertion tube without using an adhesive, safety to the living body can be ensured. In addition, since the wire tip can be prevented from being exposed to the outer surface of the insertion tube, it is possible to reduce the catching on the guiding catheter. Note that the insertion tube may have an overlapping structure only in the wire fixing portion. In this aspect, more preferably, the wire is fixed to the insertion tube including the elongated portion. If it does in this way, since an extension part adheres to an insertion tube, an insertion tube can be pushed more stably at the time of insertion of a monorail type catheter.

  According to a seventh aspect of the present invention, in the one according to any one of the first to sixth aspects, a maximum extension amount of the extension portion is set within a range of 10 mm to 50 mm.

  In this way, breakage of the wire can be prevented while ensuring the operability of insertion and extraction of the monorail type catheter. That is, by securing the maximum extension amount of the extension portion to 10 mm or more, when the wire is pulled in a hooked state, the maximum extension amount can be immediately reached and the wire may be broken, and the extension portion can be By suppressing the extension amount to 50 mm or less and preventing excessive extension, the operability of insertion / extraction can be ensured.

  According to the monorail type catheter according to the present invention, the insertion tube of the monorail type catheter is protruded from the distal end side opening of the guiding catheter and inserted into the coronary artery to guide the treatment catheter to a position closer to the treatment site. Backup power can be obtained at a position closer to the treatment site. In the monorail type catheter, since the insertion tube is provided only at the distal end portion and the proximal end side is configured by the wire, it is not necessary to provide the proximal end device in the monorail type catheter. As a result, the number of proximal-side devices can be reduced, the catheter length required for the treatment catheter can be shortened, and a wider variety of treatment catheters can be used.

Explanatory drawing of the catheter assembly provided with the monorail type catheter as one Embodiment of this invention. Explanatory drawing which shows the monorail type catheter as one Embodiment of this invention. It is sectional drawing of the insertion tube of the monorail type catheter shown in FIG. 2, Comprising: III-III sectional drawing in FIG. It is sectional drawing of the penetration tube of the monorail type catheter shown in FIG. 2, Comprising: IV-IV sectional drawing in FIG. The principal part expansion explanatory drawing of the monorail type catheter shown in FIG. Explanatory drawing for demonstrating the PCI procedure using the catheter assembly shown in FIG. Explanatory drawing corresponding to FIG. 5 which shows the principal part of the monorail type catheter as a different aspect of this invention.

  Embodiments of the present invention will be described below with reference to the drawings.

  First, FIG. 1 shows a catheter assembly 12 including a guiding catheter structure 10. The guiding catheter structure 10 is configured by inserting a monorail type catheter 14 as an embodiment of the present invention through a guiding catheter 16. A balloon catheter 18 as a treatment catheter is inserted into the monorail type catheter 14 inserted through the guiding catheter 16 in a state of being externally inserted into the guide wire 20, and these guiding catheter structures 10 are inserted. The catheter assembly 12 includes the guide wire 20 and the balloon catheter 18.

  FIG. 2 shows a monorail type catheter 14. The monorail type catheter 14 has a structure in which a hub 23 as an operation portion is provided at the proximal end portion of the catheter main body 22. The catheter body 22 includes an insertion tube 24 provided on the distal end side and a wire 26 provided on the proximal end side and extending from the proximal end side of the insertion tube 24. The hub 23 is a member formed of hard plastic or the like, and is fixedly provided at the proximal end of the wire 26. Note that FIG. 2 and FIGS. 5 and 7 to be described later are shown through a coated tube 42 to be described later for easy understanding.

  3 and 4 show the insertion tube 24. The insertion tube 24 has a structure in which a tube tube 42 described later is fixed to the tube body 25 in an extrapolated state. The tube body 25 has a substantially constant cross-sectional shape, and has an easily curved cylindrical shape extending over a predetermined dimension. The tube main body 25 has an overlapping structure in which the outer periphery of the inner layer tube 28 is covered with the outer layer tube 30, and the inner peripheral surface 32 of the inner layer tube 28 forms the inner peripheral surface of the tube main body 25. However, the insertion tube 24 is not limited to a cylindrical shape, and may be a polygonal cylindrical shape.

  As the material for the inner layer tube 28 and the outer layer tube 30, a thermoplastic resin can be suitably employed, but it is not particularly limited as long as it has a predetermined shape retention characteristic and elasticity. As the outer layer tube 30, for example, polyamide, polyamide elastomer, polyester, or the like is adopted, and a radiopaque contrast agent is preferably blended. Examples of the contrast agent include barium sulfate, bismuth oxide, and bismuth subcarbonate. The inner layer tube 28 may be made of the above-described materials. However, the inner tube 28 affects the operability of the balloon catheter 18 and the like, and therefore has a small friction coefficient, such as polytetrafluoroethylene (PTFE) or tetrafluoroethylene. -A fluorine-based material such as perfluoroalkyl vinyl ether copolymer (PFA) is more preferably employed. The inner peripheral surface 32 of the inner layer tube 28 may be subjected to a lubrication treatment such as a surface treatment using a silicon coating or a fluororesin. In addition, as the outer layer tube 30, the above-exemplified material can be adopted. The inner layer tube 28 and the outer layer tube 30 may be made of the same material or different materials. And the outer tube 30 is extrapolated by the inner tube 28, and the tube main body 25 is formed by mutually adhere | attaching or welding.

  Further, between the inner layer tube 28 and the outer layer tube 30, a blade 34 is provided as a metal reinforcing body embedded in a mesh shape in the inner peripheral portion of the outer layer tube 30. The blade 34 is provided over substantially the entire length between the inner layer tube 28 and the outer layer tube 30.

  Further, a distal tip 36 is provided at the distal end portion of the insertion tube 24. The distal end tip 36 is welded, bonded, or integrally formed to the distal end portions of the inner layer tube 28 and the outer layer tube 30. The tip 36 has a cylindrical shape in which a contrast medium is blended with the above-described material similar to the inner layer tube 28 and the outer layer tube 30, and its inner diameter is made equal to the inner diameter of the inner layer tube 28. The outer diameter dimension is made equal to the outer diameter dimension of the outer layer tube 30. In the present embodiment, a contrast agent is blended in the distal tip 36 so that the distal end position of the insertion tube 24 can be confirmed under intraoperative radioscopy. However, instead of or in addition to the contrast agent, the insertion tube A marker made of a radiopaque material such as stainless steel or platinum alloy may be provided at the tip of 24.

  As shown in FIG. 5, an extended distal end portion 38 of the wire 26 is fixed to the proximal end portion of the insertion tube 24. At the extending tip portion 38 of the wire 26, a hook-shaped portion 40 is formed as a connecting portion bent in a U-shape on the opposite side to the extending direction (left direction in FIG. 5). Then, the hook-shaped portion 40 is superimposed on the outer peripheral surface of the proximal end portion of the outer layer tube 30 in the tube main body 25, and the coated tube 42 formed separately from the tube main body 25 is formed from the outside of the hook-shaped portion 40. The collar 40 is sandwiched between the outer layer tube 30 and the covering tube 42 and fixed to the insertion tube 24 by being overlapped and attached to the outer layer tube 30 in an extrapolated state. As the material of the covering tube 42, the same resin material as that of the outer layer tube 30 is preferably used. In addition, an adhesive may be used to attach the covering tube 42 to the outer layer tube 30, but thermal welding is preferably employed from the viewpoint of safety to the living body. For example, the tube-shaped portion 40 of the wire 26 is overlapped on the outer surface of the outer layer tube 30, and the covering tube 42 is further overlapped on the outer side, and both the tubes 30 and 42 are brought into close contact with each other while applying external pressure as required, and melted. As a result, the covering tube 42 is welded to the outer layer tube 30 so as to embed the flanged portion 40.

  In addition, although the covering tube 42 in this embodiment is attached only to the base end part of the tube main body 25 with which the bowl-shaped part 40 was overlapped, the covering tube 42 is overlapped over the entire length of the tube main body 25. Also good. When the covering tube 42 is overlapped over the entire length of the tube body 25, the outer diameter of the distal tip 36 is made equal to the outer diameter of the covering tube 42 by, for example, fixing the distal tip 36 to the covering tube 42. It is preferable. Further, the base end side end portion of the covering tube 42 protrudes from the tube body 25 to the base end side and is opened obliquely, so that the insertion of the balloon catheter 18 into the insertion tube 24 within the guiding catheter 16 is facilitated. At the same time, it is easy to move in the extraction direction within the guiding catheter 16 by reducing the catch.

  Further, in the wire 26, an extending portion 44 is formed on the proximal end side from the extended distal end portion 38 fixed to the insertion tube 24. The elongated portion 44 is formed by bending or bending the wire 26 in a wave shape. The maximum extension amount of the extension portion 44 is preferably set within a range of 10 mm to 50 mm, and more preferably within a range of 20 mm to 40 mm. By securing the maximum extension amount of the extension portion 44 to 10 mm or more, the extension portion 44 immediately reaches the maximum extension amount when the insertion tube 24 is caught and the wire 26 is not broken, and the maximum extension amount is 50 mm. By suppressing to the following, it is possible to suppress excessive elongation and secure the strength of the wire 26 and to secure the operability of insertion / extraction of the monorail type catheter 14.

  The formation position of the elongated portion 44 is not particularly limited as long as it is on the transmission path of the operating force transmitted to the insertion tube 24 through the wire 26. Therefore, it is not limited to the wire 26 and can be provided on the insertion tube 24 or the hub 23. In the present embodiment, an elongated portion 44 is formed on the distal end side of the wire 26 that is close to the hook-shaped portion 40. Then, the elongated portion 44 is overlaid on the proximal end portion of the tube main body 25 together with the flange-shaped portion 40, and the covering tube 42 is further overlapped and welded. And the covering tube 42 to be fixed to the insertion tube 24.

  The insertion tube 24 including the covering tube 42 is formed with an outer diameter that can be inserted through the guiding catheter 16 and an inner diameter that can be inserted through the balloon catheter 18 and, if necessary, the balloon catheter 18 having a stent. . Specifically, the outer diameter of the insertion tube 24 is set within a range of 0.5 mm to 2.5 mm, and more preferably within a range of 1.0 mm to 2.0 mm. The inner diameter of the insertion tube 24 is set within a range of 0.5 mm to 2.0 mm, and more preferably within a range of 1.0 mm to 1.5 mm.

  The length of the tube body 25 excluding the coated tube 42 extends from the distal opening 64 (described later) of the guiding catheter 16 positioned at the coronary artery entrance into the coronary artery, so that the distal tip 36 is near the treatment site. It is preferable to have a length dimension that can reach the distance to the treatment site, that is, a length dimension corresponding to the distance from the coronary artery entrance to the treatment site. Specifically, it is set within a range of 100 mm to 500 mm, more preferably 150 mm to 300 mm.

  Furthermore, the length dimension of the catheter body 22 including the insertion tube 24 and the wire 26 is such that the insertion tube 24 can protrude from a distal end side opening 64 of the guiding catheter 16 described later and the hub 23 is described later. The guiding catheter 16 is set to be larger than the length of the guiding catheter 16 so as to protrude from the proximal end opening 65 and maintain the operable state. Specifically, the length of the catheter body 22 is 500 mm to 2000 mm, and more preferably longer than 1000 mm to 1500 mm, as compared to the total length of the guiding catheter 16 including the Y connector 48 described later. Is set.

  The monorail type catheter 14 having such a structure is inserted through the guiding catheter 16 as shown in FIG. Since a conventionally known guiding catheter 16 can be appropriately employed as the guiding catheter 16, only an outline will be described. The guiding catheter 16 has a structure in which a Y connector 48 serving as a proximal device is provided at the proximal end of a bendable tubular flexible tube 46. Similar to the tube main body 25 of the monorail catheter 14, the flexible tube 46 has a superposed structure made of a thermoplastic resin tube in which a metal reinforcing material is embedded. In addition, a distal end tip 47 that is made radiopaque by mixing a contrast agent or the like is provided at the distal end of the flexible tube 46. As is clear from this, the tube main body 25 of the monorail type catheter 14 has a structure substantially similar to that of a conventionally known guiding catheter tube.

  A Y connector 48 is provided on the proximal end side of the flexible tube 46. A check valve (not shown) is provided in the Y connector 48 to prevent blood from flowing backward. Further, the Y connector 48 is provided with a side arm 50 branched from the main body portion, and a drug solution or a contrast medium can be injected through the side arm 50.

  Further, a guide wire 20 and a balloon catheter 18 are inserted into the monorail type catheter 14. As the guide wire 20 and the balloon catheter 18, conventionally known ones can be appropriately employed. As the balloon catheter 18, a conventionally known rapid exchange type is preferably used. A balloon 54 formed of a flexible soft synthetic resin such as polyamide, polyethylene, polyethylene elastomer, polyurethane, or a rubber film is provided at the distal end portion of the catheter body 52 that can be bent in the balloon catheter 18. It has been. The pressure fluid such as gas or liquid is supplied and discharged into the balloon 54 through the catheter body 52, whereby the expansion and contraction of the balloon 54 is controlled.

  The catheter assembly 12 includes the guiding catheter 16, the monorail type catheter 14, the guide wire 20, and the balloon catheter 18, and the monorail type catheter 14 is inserted into the guiding catheter 16 and the monorail type catheter 14. On the other hand, the balloon catheter 18 inserted through the guide wire 20 is inserted.

  When the stenosis in the coronary artery of the heart is expanded by percutaneous coronary angioplasty (PTCA) using such a catheter assembly 12, first, as shown in FIG. 6, the patient's radial artery 56 is punctured. Then, the distal end of the sheath 58 is inserted into the radial artery 56 from the puncture site. Next, a guide wire for a known guiding catheter (not shown) is inserted into the radial artery 56 through the sheath 58, and is inserted from the radial artery 56 through the brachial artery 60 to the ascending aorta 62. Subsequently, the guiding catheter 16 is extrapolated to the guiding wire for the guiding catheter and inserted into the radial artery 56 from the sheath 58, and the distal side opening 64 is formed in the coronary artery 66 along the guiding wire for the guiding catheter. Located at the entrance. In addition, since the contrast agent is mix | blended with the front-end | tip tip 47 of the guiding catheter 16, the position of the front-end | tip tip 47 can be visually recognized under radiation imaging. Then, only the guide wire for the guiding catheter is removed from the artery.

  Next, the catheter body 22 of the monorail type catheter 14 is inserted from the proximal end side opening 65 of the Y connector connected to the guiding catheter 16, and the insertion tube 24 is protruded from the distal end side opening 64 of the guiding catheter 16. Are inserted into the coronary artery 66 and the distal tip 36 is positioned in front of the stenosis 68. As with the tip tip 47 of the guiding catheter 16, since the contrast agent is blended in the tip tip 36, the position of the tip tip 36 can be visually recognized under radiographic imaging. It can be positioned closely and accurately. Thereafter, the guide wire 20 for the balloon catheter 18 is inserted into the guiding catheter 16 from the proximal-side opening 65, and is inserted into the insertion tube 24 of the monorail type catheter 14 within the guiding catheter 16. The distal tip 36 is inserted into the coronary artery 66 to reach a position where the distal end passes through the stenosis 68.

  Subsequently, the balloon catheter 18 is inserted from the proximal opening 65 of the guiding catheter 16 in a state of being extrapolated to the guide wire 20, and the monorail type catheter 14 is guided along the guide wire 20 in the guiding catheter 16. The insertion tube 24 is inserted. Then, while guiding the balloon 54 with the insertion tube 24, the balloon 54 is inserted into the coronary artery 66 from the distal tip 36 and pushed into the stenosis 68. Thereafter, the balloon 54 is inflated to expand the stenosis 68 and restore the blood flow in the stenosis 68.

  The above procedure is merely an example, and PTCA has been described by taking the procedure using the transradial artery approach (TRI) as an example. However, the catheter assembly 12 of the present invention may be used for the procedure using the transfemoral artery approach (TFI). Is possible. Further, if necessary, the stent may be placed in the stenosis portion 68 by being pushed into the stenosis portion 68 with a known stent extrapolated to the balloon 54. Furthermore, the insertion order of each catheter and guide wire constituting the catheter assembly 12 is not limited to the above order.

  If the monorail type catheter 14 according to the present embodiment is used, the insertion tube 24 protrudes from the distal end opening 64 of the guiding catheter 16 positioned at the entrance of the coronary artery 66 and is inserted into the coronary artery 66, whereby the balloon catheter 18 is inserted. By guiding into the coronary artery 66 and supporting the coronary artery 66, a backup force to the balloon catheter 18 can be obtained at a position closer to the stenosis 68. Thereby, even when the stenosis of the stenosis 68 is strong or the stenosis 68 is separated from the entrance of the coronary artery 66, the balloon 54 of the balloon catheter 18 can be easily pushed into the stenosis 68.

  Further, since the proximal end side of the catheter body 22 is formed by the wire 26, friction with the inner peripheral surface of the guiding catheter 16 is reduced, and insertion / extraction with respect to the guiding catheter 16 becomes easy. At the same time, since the clearance in the guiding catheter 16 is secured by the wire 26, the balloon catheter 18 can be easily inserted and removed.

  Furthermore, since the Y connector 48 such as the guiding catheter 16 is not required, the number of proximal devices can be reduced. As a result, even when the monorail type catheter 14 is used, the balloon catheter 18 can be inserted from the Y connector 48 of the guiding catheter 16 as in the case where the monorail type catheter 14 is not used. Thereby, the catheter length required for the balloon catheter 18 can be shortened, and more types of balloon catheters 18 can be used.

  In addition, since the extending portion 44 is provided on the wire 26, for example, when the guide tube 16 is removed from the guiding catheter 16, the insertion tube 24 is caught on the inner peripheral surface of the guiding catheter 16 and the like, so that there is no normal removal. When a predetermined tensile force larger than that sometimes exerted is applied to the wire 26, the elongated portion 44 is extended while breaking the fixing surface between the tube body 25 and the covering tube 42, whereby the wire 26 and the insertion tube are expanded. The tensile force exerted on the connecting portion with the wire 24 can be relaxed to prevent the wire 26 from being broken. Furthermore, the operator can recognize the catch of the insertion tube 24 by the operational feeling that the extension part 44 extends, and the breakage of the wire 26 due to excessive tension can be prevented. In particular, the elongated portion 44 in the present embodiment has the weakest tensile strength and is positioned in the vicinity of the connecting portion between the insertion tube 24 and the wire 26 that is easily broken, so that the breakage can be effectively prevented and the insertion is made. The possibility that the extending portion 44 extends due to a cause other than the catching of the tube 24 is reduced, and a more reliable breakage preventing effect against the catching of the insertion tube 24 can be exhibited.

  Furthermore, since the extended portion 44 is sandwiched between the tube body 25 and the covering tube 42 and is fixed to the insertion tube 24 together with the hook-shaped portion 40, the insertion portion 24 is stable when inserted into the guiding catheter 16. Can exert the pushing force. In particular, since the hook-shaped portion 40 has a U-shaped hook shape, it is possible to secure a larger overlapping area on the tube body 25 and to obtain a stronger fixing force. In addition, the covering tube 42 is fixed to the tube main body 25 by heat welding with the flange portion 40 and the extending portion 44 interposed therebetween. Thereby, the wire 26 can be firmly sandwiched and held, and since no adhesive is used, safety to the living body is also ensured. In addition, since the linear wire 26 is sandwiched and fixed between the tube body 25 and the covering tube 42, there is little possibility that a partial protrusion is formed on the outer peripheral surface of the insertion tube 24. Thereby, the outer peripheral surface shape of the insertion tube 24 can be made smooth, and the possibility of catching can be further reduced.

  As mentioned above, although embodiment of this invention was explained in full detail, this invention is not limited by the specific description. For example, the decompression part may be one in which only decompression deformation is allowed without being restored, but the decompression part is restored to its original state after decompression as shown in FIG. You may comprise as the elastic expansion | extension part 70 which can be restored | restored. The elastic extension part 70 in this aspect is formed as a spring formed by bending or bending the wire 26 in a wave shape, and is elastic when a greater tensile force is exerted on the wire 26 without being caught. It is an extension spring. The hook-like portion 40 of the wire 26 is sandwiched between the tube main body 25 and the covering tube 42 and fixed to the insertion tube 24, and is elastically extended to the proximal end portion of the covering tube 42 protruding from the tube main body 25. The part 70 is accommodated. Thereby, the possibility of the elastic extension part 70 being caught in the guiding catheter 16 is reduced.

  According to the present aspect, when the tensile force exerted on the wire 26 without being caught is exerted on the wire 26 due to the hooking of the insertion tube 24 or the like, the elastic extension portion 70 extends, whereby the wire 26 26 breakage can be prevented. Since the elastic extension portion 70 can be restored to its original state when the tensile force is released, for example, when the insertion tube 24 is caught, it is possible to repeatedly perform the pulling and releasing thereof. By doing so, it is possible to make the operator clearly recognize whether or not the catch has been eliminated, and it is possible to obtain better operability.

Further, as described above, the extension portion may be provided on the transmission path of the operating force of the monorail type catheter. For example, in the above-described embodiment, not only the wire 26 but also the insertion tube 24 and the hub 23 may be partially or wholly extendable and an extension portion may be provided. The extending portion may be formed separately from the insertion tube 24, the wire 26, and the hub 23, and any one or some of the insertion tube 24, the wire 26, and the hub 23 are divided at appropriate positions. Then, for example, an extending portion may be formed by providing an extending member such as a rubber elastic body, a resin spring, or a metal spring at the divided portion. In addition, it is possible to provide a plurality of extending portions on the operating force transmission path.

  Further, the specific shape of the connecting portion of the wire to the insertion tube is not limited to the U-shape such as the hook-shaped portion 40. For example, the L-shape, the folded shape, the circular shape, the U-shape, the cross Various shapes such as a shape and a spiral shape can be appropriately employed. Furthermore, a larger fixing area may be secured by making the connecting portion into a plate shape.

  Furthermore, it is possible to insert and fix the wire to the insertion tube, and in this way, a double tube overlapping structure is unnecessary and can be firmly fixed. For example, when forming an insertion tube or when forming an outer layer tube on the outer periphery of the inner layer tube, such as two-color molding, the inner layer tube is set in the outer cavity of the outer layer tube, and a wire is formed on the outer peripheral surface of the inner layer tube. The tip of the wire is placed on top of each other, and the molding cavity is filled with the molding material of the outer layer tube. The part can be fixed by insert molding. Note that the wire tip is preferably covered with a tube such as the above-described embodiment or the above outer-layer tube and fixed without using an adhesive, from the viewpoint of prevention of catching and biological safety. You may adhere | attach to the outer surface of an insertion tube simply by adhesion | attachment etc., without covering with a tube.

  Further, the therapeutic catheter is not within the scope of the right of the present invention, and the present invention is not limited at all by the type, but the therapeutic catheter inserted through the guiding catheter of the present invention is limited to the balloon catheter. Instead, a rotablator (RA), directional atherectomy (DCA), and other conventionally known various catheters can be arbitrarily employed.

10: guiding catheter structure, 12: catheter assembly, 14: monorail type catheter, 16: guiding catheter, 18: balloon catheter (treatment catheter), 20: guide wire, 22: catheter body, 23: hub, 24: Insertion tube, 25: Tube body, 26: Wire, 28: Inner layer tube, 30: Outer layer tube, 32: Inner peripheral surface, 34: Blade, 36: Tip, 38: Extension tip (wire), 40 : Saddle-shaped part (connection part), 42: Covered tube, 44: Elongation part, 48: Y connector, 54: Balloon, 64: Front end side opening part, 65: Proximal end side opening part, 70: Elastic extension part (elongation) Part)

Claims (7)

A monorail type catheter that has a length that is inserted from the proximal end side opening portion of the guiding catheter and protrudes from the distal end side opening portion, and that guides the distal end portion of the treatment catheter to the treatment site through the treatment catheter. Because
The monorail type catheter is provided with an insertion tube protruding from the distal end side opening of the guiding catheter through which the treatment catheter is inserted, and the insertion tube includes the insertion tube. A wire that extends from the proximal end side of the guiding catheter and protrudes from the proximal end side opening of the guiding catheter is connected, and a transmission path for operating force of the monorail catheter that is transmitted to the insertion tube through the wire A monorail type catheter characterized by further comprising an extending portion that can be extended when a predetermined tensile force is applied to the wire.   The monorail type catheter according to claim 1, wherein the extension portion is an elastic extension portion capable of elastic extension.   The monorail type catheter according to claim 1 or 2, wherein the elongated portion is provided at an end of the wire on the insertion tube side.   The monorail type catheter according to any one of claims 1 to 3, wherein the elongated portion is formed by bending the wire in a wave shape.   The monorail type catheter according to any one of claims 1 to 4, wherein an odd-shaped connecting portion is provided at a distal end portion of the wire, and the wire is fixed to the insertion tube at the connecting portion.   The insertion tube has an overlapping structure of a plurality of tubes, and the distal ends of the wires are welded by sandwiching the distal ends of the wires between the stacked tubes, so that the distal ends of the wires are attached to the insertion tube. The monorail type catheter according to any one of claims 1 to 5, which is fixed.   The monorail type catheter according to any one of claims 1 to 6, wherein a maximum extension amount of the extension part is set within a range of 10 to 50 mm.

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