JP2006280668A - Suction catheter and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a suction catheter having a rapid exchange type structure, capable of sucking thrombi dispersed in a peripheral direction inside a blood vessel and the thrombi blocked by a distal protection device. <P>SOLUTION: The suction catheter comprises a catheter tube provided with a suction lumen 30 and provided with openings on a distal end, a proximal end and a side wall, and a guide wire insertion tube 50 provided with a guide wire lumen 20. The distal end opening of the catheter tube is a plurality of suction ports 34 and a guide wire insertion tube receiving hole, the guide wire insertion tube is positioned inside the suction lumen of the catheter tube 60, and the proximal end of the guide wire insertion tube is attached to the catheter tube so that the proximal end opening of the guide wire insertion tube and the opening of the side wall of the catheter tube match. The distal end part of the guide wire insertion tube is inserted to the guide wire insertion tube receiving hole of the catheter tube, and the distal end opening of the guide wire insertion tube is positioned at the distal end of the catheter tube or more on the distal side than the distal end. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a suction catheter used for sucking and removing a thrombus or the like in a blood vessel, and more particularly to a suction catheter having a rapid exchange structure and excellent suction performance, and a method for manufacturing the same.

  For myocardial infarction in which the coronary artery is occluded by a thrombus and the blood flow in the coronary artery is obstructed, a treatment method in which the occlusion site is expanded by a balloon catheter is mainly used. However, when the occlusion site is expanded by the balloon catheter, the thrombus may be detached from the occlusion site and flow out, and the peripheral blood vessel may clog the thrombus. Therefore, when a balloon catheter is used in a case where the coronary artery is occluded by a large amount of thrombus, severe peripheral embolism may be induced.

  In recent years, for such cases, a treatment method (coronary thrombus aspiration therapy) that sucks and removes a thrombus using an aspiration catheter as described in Patent Document 1 or Patent Document 2 is effective. It has become clear.

  The aspiration catheter described in Patent Document 1 has a guide wire lumen 15 for inserting a guide wire as shown in FIG. 4 in order to be inserted along a guide wire inserted into a blood vessel. In this suction catheter, a structure (rapid exchange type structure) having a guide wire lumen 15 over the distal end portion and the middle abdominal portion of the catheter is employed.

  In this rapid exchange type structure suction catheter, the guide wire and the catheter on the proximal end side (outside the body) are different from the catheter having the guide wire lumen over the distal end portion and the proximal end portion (over the wire type structure). Are separated, it is possible to pull back only the catheter without moving the guide wire. Therefore, after the thrombus has been aspirated with this suction catheter, only the catheter can be extracted from the blood vessel while leaving the guide wire in the blood vessel. This catheter can be inserted along with this, and the subsequent treatment can be performed quickly. Due to this advantage, a rapid exchange type structure is used as the suction catheter.

JP 2004-222946 A JP 2004-65326 A

  However, the suction catheters described in Patent Document 1 and Patent Document 2 have insufficient aspects in thrombus suction performance. That is, in the suction catheter having such a structure, since the suction port is oriented only in one direction, for example, the suction catheter of FIG. 4 can suck the thrombus in the X direction in the blood vessel, but the guide wire side There is a problem that it is impossible to suck the thrombus in the Y direction.

  Also, when using an aspiration catheter, prevent thrombus from flowing into peripheral blood vessels to prevent peripheral embolism from being induced by a thrombus that has not been aspirated by the catheter and peeled off from the obstruction site. In some cases, a distal protection device is used together. A distal protection device is a device that has a member at the tip that blocks a solid material that flows in a blood vessel, such as a net or balloon, and captures blood clots that flow through the bloodstream. To prevent blood clots from flowing in the peripheral direction. However, for example, when a distal protection device is used in combination with a suction catheter having a rapid exchange type structure as shown in FIG. 4, the tip of the catheter collides with a balloon or the like, so that the suction port is sufficiently close to the vicinity of the balloon or the like. In other words, the thrombus blocked by a balloon or the like cannot be sufficiently sucked.

  The present invention has been made in view of the above-mentioned problems, and can efficiently suck a thrombus scattered in the circumferential direction in a blood vessel. In addition, when a distal protection device is used in combination, the present invention is blocked. It is an object of the present invention to provide a rapid exchange type structure suction catheter that can sufficiently suck the stopped thrombus and has excellent suction performance.

  As a result of intensive studies on the structure of the tip portion of the rapid exchange type suction catheter, the present inventor has found that the above problem can be solved by increasing the number of suction ports using a catheter tube having a specific structure. The present invention has been completed.

  Thus, according to a first aspect of the present invention, a catheter tube having a suction lumen therein and having openings at its distal end, proximal end and side walls, and a guide wire lumen therein, the distal A suction catheter having a guide wire insertion tube having openings at the distal end and the proximal end, wherein the distal end opening of the catheter tube is a plurality of suction ports and guide wire insertion tube receiving holes, and the guide wire The proximal end of the guide wire insertion tube is positioned on the catheter tube so that the insertion tube is positioned within the suction lumen of the catheter tube and the opening of the proximal end of the guide wire insertion tube and the side wall of the catheter tube coincide. The distal end of the guide wire insertion tube is inserted into the guide wire insertion tube receiving hole of the catheter tube, and the distal end opening of the guide wire insertion tube is inserted into the distal end of the catheter tube or Than the distal end of the ether tube is positioned distally, the suction catheter is provided.

  In the above suction catheter, at the distal end of the catheter tube, the axis of the catheter tube and the axis of the guide wire insertion tube coincide with each other, and a plurality of suction ports of the catheter tube are provided on the guide wire insertion tube. It is preferable to arrange | position around.

  In the above suction catheter, the plurality of suction ports of the catheter tube are preferably arranged at substantially equal intervals in the circumferential direction of the catheter tube.

  According to the second aspect of the present invention, the step of providing one opening on the side wall of the first tube, the step of processing one end of the first tube into a shape having at least three openings, Inserting a second tube over the opening of the side wall and one of the end openings of one tube, and joining the edge of the opening of the side wall of the first tube and the outer peripheral surface of the second tube in a liquid-tight manner There is provided a method of manufacturing the above-described suction catheter, including the step of: joining the edge of the opening at the end of the first tube and the outer peripheral surface of the second tube.

  Since the suction catheter of the present invention has a plurality of suction ports, thrombus scattered in the circumferential direction in the blood vessel can be sucked evenly by suction ports that are directed in different directions. In addition, by distributing the suction force generated by the negative pressure source connected to the proximal end side of the catheter tube to a plurality of suction ports, thrombus in the vicinity of the balloon or the like of the distal protection device can also be efficiently suctioned. . Furthermore, since the catheter of the present invention has a rapid exchange structure, it is possible to extract only the catheter from the blood vessel while leaving the guide wire in the blood vessel. It is possible to perform treatment.

Hereinafter, in order to facilitate understanding of the present invention, description will be made with reference numerals attached to the accompanying drawings. However, the present invention is not limited to the illustrated embodiments.
FIG. 1 is a side view of an aspiration catheter 100, which is an example of an embodiment of the present invention. The suction catheter 100 is configured by connecting a catheter tube 60 to a connector 80 at a proximal end thereof and fitting a strain relief 70 to the connection portion.

  FIG. 2 is an enlarged cross-sectional view of the distal end portion of the catheter tube 60. The distal end portion of the catheter tube 60 has a tapered shape (tapered shape) so that it can be easily inserted into a coronary artery or the like. The catheter tube 60 has two suction ports 34 at the tapered distal end thereof, and a suction lumen that extends from the suction port 34 to a proximal end opening (not shown) of the catheter tube 60 therein. 30 is provided.

  In the suction lumen 30 of the catheter tube 60, a tube-shaped guide wire insertion tube 50 having a guide wire lumen 20 therein is located. This guide wire insertion tube 50 is a distal end for introducing the guide wire. It has an end opening 22 and a proximal end opening 24 for guiding the guide wire. The distal end portion of the guide wire insertion tube 50 coincides with an opening (guide wire insertion tube receiving hole) other than the suction port 34 provided at the distal end of the catheter tube 60. And is attached to the catheter tube 60 so that its proximal end is fluid tightly attached so that the proximal end opening 24 coincides with the opening provided in the side wall of the catheter tube 60. It is a member. In addition, at the distal end of the catheter tube 60, the axial center of the guide wire insertion tube 50 is the catheter tube 60 in order to improve the insertability when the suction catheter 100 is inserted into the body along the guide wire. A guide wire insertion tube 50 (distal end opening 22) is arranged so as to coincide with the axial center of the guide wire.

  In the embodiment shown in FIG. 2, the distal end opening 22 of the guide wire insertion tube 50 is at the same position as the distal end of the catheter tube 60, but in the suction catheter of the present invention, the distal end of the guide wire insertion tube 50. The distal end of the guide wire insertion tube 50 is inserted into the guide wire receiving hole of the catheter tube 60 so that the end projects from the distal end of the catheter tube 60. The opening 22 may be located distal to the distal end of the catheter tube 60. However, it is preferable that the distal end opening 22 of the guide wire insertion tube 50 is closer to the distal end of the catheter tube 60. When the distal protection device is used in combination, the suction port 34 of the suction lumen 30 is positioned closer to the balloon or the like of the distal protection device as the position of the distal end opening 22 of the guide wire insertion tube 50 is closer to the distal end of the catheter tube 60. This is because the blood clot can be approached and the thrombus blocked by the distal protection device can be easily aspirated. Specifically, the distal end opening 22 of the guide wire insertion tube 50 is usually disposed 0 to 5 mm, preferably 0 to 1 mm distal to the distal end of the catheter tube 60. Most preferably, as in the embodiment shown in FIG. 2, the position is 0 mm distal to the distal end of the catheter tube 60, that is, the same position as the distal end of the catheter tube 60.

  The length of the guide wire insertion tube 50 is preferably 5 to 400 mm, and more preferably 10 to 100 mm. By setting the length of the guide wire insertion tube 50 to 5 mm or more, preferably 10 mm or more, the suction catheter 100 can be easily oriented along the guide wire inserted into the guide wire lumen 20 in the guide wire insertion tube 50. The suction catheter 100 can be easily inserted into the blood vessel. Further, by setting the length of the guide wire insertion tube 50 to 400 mm or less, preferably 100 mm or less, the volume occupied by the guide wire insertion tube 50 in the suction lumen 30 of the catheter tube 60 becomes sufficiently small. The thrombus and the like can be effectively sucked through the suction lumen 30 without hindering the suction performance. The inner diameter of the guide wire insertion tube 50, that is, the diameter of the guide wire lumen 20 is preferably slightly larger than the outer diameter of the guide wire used, and is usually 0.1 to 1.5 mm, preferably 0.3 to 0.7 mm. The thickness of the guide wire insertion tube 50 is usually 0.02 to 0.2 mm, preferably 0.05 to 0.1 mm. The material of the guide wire insertion tube 50 is not particularly limited, but usually a thermoplastic polymer material is used. Preferred are polyethylene, polyurethane and polyamide elastomer.

  A contrast marker 40 is attached to the outer peripheral surface of the guide wire insertion tube 50 of FIG. The position of the contrast marker 40 is detected by X-ray fluoroscopy and becomes a marker in the body. For example, the contrast marker 40 is made of a metal material such as gold, platinum, or tungsten. When the contrast marker 40 is attached, the position of the contrast marker 40 is detected by fluoroscopy, so that the position of the distal end portion of the catheter tube 60 is accurately grasped, and the suction catheter 100 is accurately guided to a thrombus or the like. This is preferable. The shape of the contrast marker 40 is not particularly limited, but is preferably a ring shape. The contrast marker 40 may be attached to the inner peripheral surface or the outer peripheral surface of the guide wire insertion tube 50, or may be attached to the inner peripheral surface or the outer peripheral surface of the catheter tube 60. The contrast marker 40 is preferably attached to the outer peripheral surface side of the guide wire insertion tube 50 as in the embodiment shown in FIG. By doing so, even if the joint between the contrast marker 40 and the guide wire insertion tube 50 is peeled off, the contrast marker 40 does not come off from the guide wire insertion tube 50 and can be prevented from falling into the body. .

3 is an enlarged cross-sectional view cut along a portion corresponding to AA ′ in FIG. The guide wire insertion tube 50 is located in the central portion of the suction lumen 30 so that the axial center thereof substantially coincides with the axial center of the catheter tube 60, and the suction port 34 of the catheter tube 60 is the axial center of the catheter tube 60. Two are formed at positions and shapes that are axially symmetric with respect to each other. In this manner, by providing a plurality of suction ports 34, the suction force by the negative pressure generation source connected to the proximal end of the suction catheter 100 can be effectively distributed, and effective thrombus suction can be performed. In addition, since each suction port 34 is a suction port facing in a different direction, thrombus scattered in the circumferential direction of the blood vessel, which is difficult to reach with one suction port, can be efficiently suctioned. In the illustrated embodiment, two suction ports 34 of the catheter tube 60 are provided, but the number of suction ports 34 is usually 2 to 10, preferably 2 to 6, and most preferably 2 to 3. . The plurality of suction ports 34 should be arranged at substantially equal intervals in the circumferential direction of the catheter tube so that the suction force can be made uniform in the circumferential direction and the thrombus can be efficiently suctioned without unevenness. Is preferred. “Substantially equidistantly spaced” means that the suction ports do not need to be arranged at exactly equal intervals, and the suction ports 34 are not partially biased in the circumferential direction of the catheter tube 60, and the peripheral portions This means that it is only necessary to be distributed in the direction. The size of each suction port 34 is usually 1 to 10 mm, preferably 2 to 4 mm in the length direction of the catheter tube 60, and the circumferential direction of the catheter tube 60 is not particularly limited, but is usually 0.5 mm to 2 mm. The area of each suction port 34 is 0.3 to ²⁰ mm ² , preferably 1 to 5 mm ² . The shape is not particularly limited, but is preferably approximately elliptical.

  The total length of the catheter tube 60 is determined by the distance from the insertion position into the body to the occlusion position such as a thrombus, and is usually 500 to 2000 mm. The outer diameter of the catheter tube 60 is determined by the inner diameter of the blood vessel into which the suction catheter 100 is inserted, and is usually 0.51 to 4.0 mm.

  The catheter tube 60 is preferably formed of a flexible organic polymer material. Specific examples thereof include polyethylene, polyethylene terephthalate, polypropylene, ethylene-propylene copolymer, and ethylene-vinyl acetate copolymer. Examples of the polymer include polyvinyl chloride, cross-linked ethylene-vinyl acetate copolymer, polyether ether ketone, polyurethane, polyamide, polyamide elastomer, polyimide, silicone rubber, natural rubber, and fluorine resin such as polytetrafluoroethylene. Among these, it is particularly preferable to use any one of fluorine resins such as polyurethane, polyethylene, polyamide, polyamide elastomer, and polytetrafluoroethylene.

  The catheter tube 60 may be a laminated tube by laminating two or more kinds of polymer materials. Further, the catheter tube 60 may be configured by changing the material used in the longitudinal direction of the suction catheter 100. In this case, it is preferable to change the material so that the catheter tube 60 becomes flexible from the proximal end toward the distal end because the insertion property of the suction catheter 100 into the blood vessel is improved.

  Furthermore, a reinforcing member such as a metal net-like material or a metal wire material can be embedded in the catheter tube 60. It is preferable to embed a reinforcing member because the thickness of the catheter tube 60 can be reduced while maintaining the strength necessary for the catheter tube 60. Accordingly, the suction area of the suction catheter 100 can be improved by increasing the sectional area of the suction lumen 30 without increasing the outer diameter of the catheter tube 60. However, this reinforcing member is preferably provided only around the suction lumen 30 other than the tip portion. If a reinforcing member is provided at the distal end portion of the catheter tube 60, it becomes too rigid and it becomes difficult to insert the suction catheter 100 into the coronary artery, and there is a risk of damaging the blood vessel during insertion. It is.

  An example of the structure of the catheter tube 60 is a catheter tube 60 in which the tip portion is formed of polyamide elastomer and the remaining portion has a three-layer structure. In this three-layer structure, the inner layer is formed of polytetrafluoroethylene, the intermediate layer is formed of a mesh member such as stainless steel as a reinforcing member, and the outer layer is far from the proximal end side in the longitudinal direction of the suction catheter 100. The three-layer structure is formed by changing the materials in the order of polyamide, relatively rigid polyamide elastomer, and relatively soft polyamide elastomer toward the end.

  The outer peripheral surface of the catheter tube 60 is preferably coated with a hydrophilic polymer material having lubricity from the viewpoint of reducing friction when the suction catheter 100 is inserted into the blood vessel. The hydrophilic polymer substance includes a natural polymer type and a synthetic polymer type. Examples of the natural polymer type include starch type, cellulose type, tannin / lignin type, polysaccharide type, and protein type. Synthetic polymers include PVA, polyethylene oxide, acrylic acid, maleic anhydride, phthalic acid, water-soluble polyester, ketone aldehyde resin, (meth) acrylamide, polyamine, water-soluble nylon Etc. are exemplified.

  Among these, cellulose-based polymer materials (for example, hydroxypropylcellulose), polyethylene oxide-based polymer materials (for example, polyethylene glycol), maleic anhydride-based polymer materials (for example, methyl vinyl ether maleic anhydride copolymer) A maleic acid copolymer) and an acrylamide polymer material (for example, polydimethylacrylamide) are particularly preferable as the above-mentioned hydrophilic polymer material because a film having a low friction coefficient can be stably obtained.

  The catheter tube 60 described above is connected to the connector 80 at its proximal end. The connector 80 is a cylindrical body provided with a port therein, and its proximal end has a structure that can be connected to a negative pressure generating source such as a suction pump equipped with a syringe or a trap. The material of the connector 80 is not particularly limited. For example, it is preferable to use a thermoplastic resin such as a polypropylene resin, an ABS resin, a polycarbonate resin, a polyamide resin, or a polyacrylate resin.

  The strain relief 70 that is externally fitted to the connection portion between the catheter tube 60 and the connector 80 is a cylindrical body that is externally fitted to the connection portion between the catheter tube 60 and the connector 80, and is perpendicular to the longitudinal direction of the suction catheter 100. From the direction, it has a role of absorbing force applied to the catheter tube 60. Since there is a large difference in rigidity between the low-rigidity catheter tube 60 and the high-rigidity connector 80, stress is easily concentrated on the catheter tube 60 at the connection point between the catheter tube 60 and the connector 80, and the catheter tube 60 is bent and damaged. Phenomenon (kink phenomenon) may occur. The strain relief 70 solves this problem. The strain relief 70 is externally fitted to the connection portion between the catheter tube 60 and the connector 80, so that the catheter tube 60 and the connector 80 are perpendicular to the longitudinal direction of the suction catheter 100. It is possible to disperse the force applied to the vicinity of the connection portion with the kink phenomenon. The material of the strain relief 70 is preferably a material rich in elasticity having an intermediate rigidity between the catheter tube 60 and the connector 80 such as polyolefin-based elastomer.

  In using the suction catheter 100 having the above-described configuration, first, a guide wire is inserted into the blood vessel of the patient to the occluded portion of the coronary artery, and then the proximal end side of this guide wire is the distal end of the guide wire insertion tube 50. It is inserted from the end opening 22 toward the proximal end opening 24. The suction catheter 100 is inserted into the blood vessel by pushing the suction catheter 100 into the blood vessel along the guide wire until the distal end reaches the occluded portion of the coronary artery.

  When the distal end reaches the occluded portion of the coronary artery, a negative pressure source such as a syringe or a suction pump equipped with a trap is connected to the connector 80 to generate a suction force at the suction port 34. With this suction force, a thrombus or the like in the coronary artery is sucked into the suction lumen 30 from the suction port 34. The aspirated thrombus or the like is held in the aspiration lumen 30 or discharged from the proximal end opening and captured in a syringe or a trap of a suction pump. Blood flow is restored in the coronary arteries from which blood clots have been sucked and removed. Thereafter, when subsequent treatment with another catheter is required, only the suction catheter 100 is extracted from the blood vessel, and the guide wire left in the blood vessel is used as it is, and the other catheter is inserted along the guide wire. Subsequent treatment can be performed.

  A method for manufacturing the catheter tube 60 of the suction catheter 100 of the present invention is not limited, but a particularly preferable manufacturing method will be described below.

  First, a first tube to be a catheter tube 60 is prepared, and the outer diameter of the guide wire insertion tube 50 is set at a position on the side wall of the first tube to be the opening 24 on the proximal end side of the guide wire insertion tube 50. An opening that is approximately the same as or slightly smaller than that is provided. In order to provide a guide wire insertion tube receiving hole and a plurality of suction ports 34 at one end of the first tube, a process of forming at least three openings is performed. This processing method is not particularly limited, for example, a method of attaching another member that has been processed into a shape having three or more openings in advance, or three or more after sealing the end of the tube once by thermoforming The method of providing an opening is mentioned. In addition, according to this process, you may perform the process which makes the distal end part of the catheter tube 60 a taper shape.

  Next, a second tube to be the guide wire insertion tube 50 is prepared, and the second tube is inserted across the guide wire insertion tube receiving hole of the first tube and the opening of the side wall. In addition, when attaching the contrast marker 40 to the second tube (guide wire insertion tube 50), it is preferable that the attachment is performed in advance. And the edge of opening of the side wall in a 1st tube and the outer peripheral surface of a 2nd tube are joined liquid-tightly by heat sealing | fusion, adhesion | attachment, etc. As this joining method, heat fusion is preferable. Specifically, a heat-shrinkable tube is provided so as to cover two tubes to be fused after inserting a core rod for holding an opening in the second tube in advance. A method of fusing by heating the heat-shrinkable tube is preferable. Then, the edge of the opening formed as the guide wire insertion tube receiving hole of the first tube and the outer peripheral surface of the second tube are joined in the same manner. This joining does not necessarily need to be liquid-tight.

  After joining, if there is an unnecessary portion of the guide wire insertion tube 50, it is removed, the proximal end of the catheter tube 60 formed in this way is connected to the connector 80, and the strain relief 70 is attached to this connection point. The suction catheter 100 of the embodiment shown in FIG. 1 is manufactured by external fitting. In addition, the manufacturing method of the suction catheter 100 of this invention does not necessarily need to be performed in the order described so far, and can change the order of a process in the range which does not deviate from invention.

It is a side view showing the whole suction catheter 100 which is an example of an embodiment of the present invention. 4 is an enlarged cross-sectional view showing a distal end portion of the catheter tube 60. FIG. FIG. 3 is an enlarged sectional view of a portion corresponding to A-A ′ in FIG. 2. It is a figure which shows the front-end | tip part of the catheter of patent document 1 which is a prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Aspiration catheter 20 Guide wire lumen 22 Distal end opening 24 Proximal end opening 30 Aspiration lumen 34 Aspiration port 40 Contrast marker 50 Guide wire insertion tube 60 Catheter tube 70 Strain relief 80 Connector

Claims (4)

A catheter tube having a suction lumen therein and having openings at its distal end, proximal end and sidewalls, and a guide wire passage having a guide wire lumen therein and openings at its distal and proximal ends A suction catheter comprising a tube,
The distal end opening of the catheter tube is a plurality of suction ports and a guide wire insertion tube receiving hole,
The guidewire insertion tube is located within the suction lumen of the catheter tube;
The proximal end of the guide wire insertion tube is attached to the catheter tube such that the proximal end opening of the guide wire insertion tube and the opening of the side wall of the catheter tube coincide with each other,
The distal end portion of the guide wire insertion tube is inserted into the guide wire insertion tube receiving hole of the catheter tube,
A suction catheter in which a distal end opening of the guide wire insertion tube is located at a distal end of the catheter tube or a distal side of the distal end of the catheter tube. At the distal end of the catheter tube, the axis of the catheter tube coincides with the axis of the guide wire insertion tube, and a plurality of suction ports of the catheter tube are provided around the guide wire insertion tube. The suction catheter according to claim 1, wherein the suction catheter is disposed in The suction catheter according to claim 1 or 2, wherein a plurality of suction ports of the catheter tube are arranged at substantially equal intervals in a circumferential direction of the catheter tube. Providing one opening on the side wall of the first tube;
Processing one end of the first tube into a shape having at least three openings;
Inserting a second tube across the side wall opening and one of the end openings of the first tube;
A step of liquid-tightly bonding the edge of the opening of the side wall of the first tube and the outer peripheral surface of the second tube;
Joining the edge of the opening at the end of the first tube and the outer peripheral surface of the second tube;
The manufacturing method of the suction catheter in any one of Claims 1-3 which have these.

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