JP4316252B2 - catheter - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a catheter used by being inserted into a living body lumen such as a blood vessel.
[0002]
[Prior art]
In recent years, endovascular surgery has been actively performed in which a catheter is inserted into a blood vessel percutaneously without a surgical operation to treat a vascular lesion. In such a procedure, it is necessary to selectively insert the catheter into a thin blood vessel that is bent, meandered, or branched in a complicated manner, and to position the distal end portion of the catheter at a target site.
[0003]
Usually, in order to insert a catheter into a blood vessel percutaneously, the catheter reaches a target site while inserting a guide wire (introduction aid) through the lumen of the catheter. At this time, a procedure in which a guide wire is preceded and the catheter follows it is generally performed.
[0004]
When guiding the catheter with the guide wire inserted into the lumen to the target site in the body, the guide wire and the catheter are moved forward and backward, and rotated on the outer end side. Therefore, the catheter is required to have torque transmission and pushability.
[0005]
In the case of a relatively thin catheter applied to a thin blood vessel, when the catheter body (catheter body) is made of a synthetic resin material, the so-called stiffness is weakened and the kink is easy to be formed. It may not be possible to obtain sufficient pushability. Therefore, a metal tube having bending elasticity is used as a catheter body of a relatively small diameter catheter.
[0006]
However, when the catheter body is composed of a metal tube, the bending rigidity is too high, particularly in the distal end portion of the catheter body, so that the catheter body can be smoothly and reliably advanced along the leading guide wire in the bent blood vessel. There is a drawback that followability (followability) is inferior.
[0007]
[Problems to be solved by the invention]
An object of the present invention is to provide a catheter with good operability that is easy to bend in a specific direction and has excellent followability while ensuring torque transmission and pushability.
[0008]
[Means for Solving the Problems]
  Such purposes are as follows (1) to (9This is achieved by the present invention.
[0009]
  (1) a tubular catheter body made of a metal material;A tube member made of a synthetic resin material covering the outer periphery of at least the distal end portion of the catheter body and fixed to the outer periphery;WithUsed with a guide wire that has a curved shape with a curved tip.A catheter,
  The catheter body is formed along the longitudinal direction so that the tube wall is depressed on at least the outer peripheral surface of the distal end portion.OneAnd a wall thickness of the tube wall of the catheter body is substantially constant over the entire circumference including the groove forming portion.Thus, the bending rigidity when the groove forming portion is curved to be inside is the bending rigidity when the groove forming portion is curved to be outside, and the groove forming portion is 90 ° The bending stiffness when bending so that different parts are inside or outside is smaller than either bending stiffness,
  The tube member is provided so as to extend further in the distal direction than the distal end of the catheter body, whereby the distal end portion of the catheter is missing from the catheter body.A catheter characterized by that.
[0010]
  (2)The catheter according to (1), wherein the catheter body has a length of 80 to 200 cm and an average outer diameter of 0.2 to 5 mm.
[0011]
  (3)The catheter according to (1) or (2) above, wherein a length of a portion of the catheter main body that is deficient in the distal end portion of the catheter is 2 to 300 mm.
[0012]
  (4)The groove is formed by plastically deforming and plastically deforming a tube wall of the catheter body having a circular cross section that has not yet been formed. The catheter according to any one of the above.
[0013]
  (5)In the plastic working, the raw catheter body is inserted into a mold having a semicircular cross-sectional shape having an inner surface with the same curvature as the outer peripheral surface of the raw catheter body, and faces the mold In a position, a jig having a projection corresponding to the groove is provided, and the jig is pressed against the unprocessed catheter body, and the unprocessed between the mold and the jig. The catheter according to (4), wherein the catheter body is relatively moved so as to be pulled out in the longitudinal direction, and the groove is gradually formed along the longitudinal direction.
[0014]
  (6) It has a portion where the depth of the groove decreases continuously or stepwise toward the proximal direction.Any of (1) to (5) aboveThe catheter according to 1.
[0015]
  (7) The catheter body is made of stainless steel or pseudoelastic alloy(1) to (6) aboveThe catheter according to any one of the above.
  (8) A plurality of slits are formed in the tube wall of the distal end portion of the catheter body, and the slits are formed to extend in a direction substantially perpendicular to the longitudinal direction of the catheter body.(1) to (7) aboveThe catheter according to any one of the above.
  (9) A spiral slit is formed in the tube wall of the distal end portion of the catheter body, and the spiral pitch of the slit becomes narrower continuously or stepwise as it goes in the distal direction.(1) to (8) aboveThe catheter according to any one of the above.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the catheter of the present invention will be described in detail based on a preferred embodiment shown in the accompanying drawings.
[0017]
<First Embodiment>
FIG. 1 is a perspective view showing a first embodiment of the catheter of the present invention (a state where a guide wire is inserted into the lumen), and FIG. 2 is a cross-sectional view (cross-sectional view) taken along line XX in FIG. 3 is a perspective view of a catheter body in the catheter shown in FIG. In the following description, the right side in FIG. 1 is referred to as “base end”, and the left side is referred to as “tip”.
[0018]
A catheter 1 shown in FIG. 1 includes an elongated catheter body 2 having bending elasticity and a hub 4 installed on the proximal end side of the catheter body 2. Hereinafter, the configuration of each unit will be described.
[0019]
The catheter body 2 is used by being inserted into a living body lumen such as a blood vessel (hereinafter represented by a blood vessel), and has a tubular shape. A lumen (lumen) 23 is formed inside the catheter body 2 from the distal end to the proximal end. When the catheter body 2 is inserted into the blood vessel, a guide wire 100 described later is inserted into the lumen 23. The lumen 23 is also used as a flow path for various liquids such as physiological saline, chemical liquid, cleaning liquid, contrast medium, and body fluid (for example, blood).
[0020]
The catheter body 2 is made of a metal material. As a result, the catheter body 2 has higher rigidity (bending rigidity, torsional rigidity) than those made of various synthetic resin materials (plastics). Therefore, even if the catheter body 2 has a relatively small outer diameter, the so-called stiffness is strong. As a result, the catheter 1 has a torque transmission property that allows the rotational force applied on the proximal end side to be reliably transmitted to the distal end side, and a force that the operator pushes to advance in the blood vessel from the proximal end side to the distal end side. It is excellent in pushability that can be reliably transmitted. In addition, the kink resistance is excellent.
[0021]
That is, the catheter 1 of the present invention is particularly suitable for a catheter that can be inserted into a relatively thin blood vessel, even if the outer diameter of the catheter body 2 is relatively small. For this reason, the outer diameter (average outer diameter) of the catheter body 2 is not particularly limited, but is preferably about 0.2 to 5 mm, and more preferably about 0.3 to 3 mm. Note that the inner and outer diameters of the catheter body 2 may each change along the longitudinal direction thereof.
[0022]
Further, the length of the catheter body 2 is not particularly limited and is appropriately determined according to the use site or case of the catheter 1, but is usually preferably about 80 to 200 cm.
[0023]
Various metal materials can be used as the constituent material of the catheter body 2, but a pseudo-elastic alloy (super elastic alloy) such as a Ni-Ti alloy or stainless steel is preferable from the viewpoint of physical properties and safety. That is, the pseudoelastic alloy or stainless steel easily returns to its original shape by unloading of stress. Pseudoelastic alloys include those subjected to hot working, cold working, or a combination thereof, and those subjected to other processing as long as they return to their original shapes after deformation. Therefore, the stress-strain curve includes not only the stress that is substantially constant even when the strain increases, but also the strain that increases as the stress increases.
[0024]
As shown in FIGS. 1 and 2, on the outer peripheral surface (side surface) of the catheter main body 2, a single groove (concave portion) 21 sinks the tube wall along the longitudinal direction (axial direction) of the catheter main body 2. It is formed in this way.
[0025]
In the present embodiment, the cross-sectional shape of the groove 21 is substantially an arc shape, but is not limited thereto, and may be a V shape, a U shape, a rectangle, an ellipse (semi-ellipse), or the like.
[0026]
The groove 21 is formed by plastically deforming the tube wall of the catheter body 2 having a circular cross section. This plastic working can be easily performed by the following method, for example. (1) The unprocessed catheter body 2 is inserted into a semicircular cross-section mold having an inner surface with the same curvature as the outer peripheral surface (side surface) of the catheter main body 2 and corresponds to the groove 21 at a position facing the mold. A jig (such as a pin) having a protrusion shaped like this is provided and pressed against the catheter body 2, and the catheter body 2 is moved in the longitudinal direction (axis) between the mold and the jig. The groove 21 is gradually formed along the longitudinal direction by moving relatively so as to be pulled out in the direction). (2) It is a male mold having a ridge having a shape corresponding to the groove 21, and is pressed on the outer peripheral surface of the catheter body 2 supported by the mold, and the groove 21 corresponding to the length of the ridge is formed at a time. Method.
[0027]
In such plastic working, the tube wall of the portion pressed by the protrusion of the jig or the male convex ridge escapes to the lumen side of the catheter body 2 to form the protruding portion 22. The wall thickness of the tube wall is substantially constant over the entire circumference of the tube including the portion where the groove 21 is formed. Thereby, even if the thickness of the tube wall of the catheter body 2 is relatively thin without any decrease in strength at the portion where the groove 21 is formed, it is possible to effectively prevent deformation or breakage at the portion where the groove 21 is formed. it can.
[0028]
When the catheter body 2 is made of a pseudoelastic alloy, the groove 21 may be formed at the same time as or before or after the cold work and the hot work.
[0029]
The catheter body 2 has such a groove 21 and thus has a property (characteristic) that its bending rigidity varies depending on the direction of bending. That is, the bending rigidity of the catheter body 2 when the groove 21 is formed so as to be inside (state indicated by A in FIG. 3) is curved so that the groove 21 is formed outside. (When indicated by B in FIG. 3) or when curved so that a portion that is 90 ° different from the formation portion of the groove 21 is inside (or outside) (state indicated by C and D in FIG. 3) Less than bending stiffness. Thereby, the catheter main body 2 of the part in which the groove | channel 21 was formed becomes easy to selectively bend in the direction shown by A in FIG.
[0030]
Since the catheter body 2 has such a property, the catheter 1 is excellent in followability (hereinafter referred to as “followability”) that can be smoothly and surely inserted in a bent blood vessel along the preceding guide wire 100. It will be. This is because, when the catheter body 2 is inserted / advanced along the preceding guide wire 100, the catheter 1 is rotated so that the groove 21 is located on the inside of the curve in accordance with the bending of the blood vessel that is complicatedly branched / curved. This is because the catheter body 2 can be easily bent following the bending of the blood vessel, and thus can be inserted and advanced smoothly and reliably.
[0031]
Thus, the catheter 1 exhibits excellent followability. Further, as described above, the catheter 1 has the catheter body 2 having relatively high rigidity and strong stiffness, and has excellent torque transmission and pushability. That is, the catheter 1 of the present invention has excellent torque transmission and pushability, and excellent followability, and is very easy to operate.
[0032]
Here, in order to demonstrate that the bending rigidity of the catheter body 2 varies depending on the direction in which the catheter body 2 is bent by the formation of the groove 21 as described above, the present inventor 3 of the metal tube as described below is used. A point bending test was performed. In this three-point bending test, the amount of bending when the metal tube was bent at three points under the following conditions was measured.
<Metal pipe>
Material: SUS304, outer diameter: 0.55 mm, inner diameter: 0.33 mm, wall thickness: 0.11 mm, depth of groove 21: 0.09 mm
<Bending conditions>
Fulcrum punch diameter: 5 mm, distance between fulcrums: 10 mm, bending speed: 1 mm / min, maximum load: 0.98 kgf
[0033]
FIG. 9 is a graph showing the measured data of the load and the amount of deflection in the three-point bending test as described above for the vertical axis and the horizontal axis, respectively. In FIG. 9, (1) when bent above the groove (indicated by A in FIG. 3), (2) when bent downward (indicated by B in FIG. 3), (3) beside the groove Data in the case of bending (state indicated by C or D in FIG. 3) and (4) no groove (normal: before attaching a groove) are shown respectively. As can be seen from FIG. 9, the amount of bending at the load of 0.98 kgf in these four cases was as follows (the larger the amount of bending, the smaller the bending rigidity).
(1) On the groove: 0.45mm
(2) Below groove: 0.33mm
(3) Next to groove: 0.30mm
(4) No groove: 0.29mm
[0034]
From the result of this three-point bending test, it is clear that the bending rigidity when the metal tube is bent so that the formation site of the groove 21 is inside (on the groove) is smaller than when the metal tube is bent in the other direction. It became. It has also been clarified that the bending rigidity when bent below and to the side of the groove maintains substantially the same rigidity as that without the groove.
[0035]
In the present embodiment, the groove 21 is formed over almost the entire length of the catheter body 2. However, in the present invention, the groove 21 may be formed only in the distal end portion of the catheter body 2. Good.
[0036]
Further, the cross-sectional shape, maximum depth, width, and the like of the groove 21 may be the same or changed along the longitudinal direction of the catheter body 2.
[0037]
As shown in FIG. 1, a radiopaque marker 5 is provided on the outer peripheral portion of the distal end of the catheter body 2. Thereby, the position of the front-end | tip of the catheter main body 2 can be confirmed under X-ray fluoroscopy. In the illustrated configuration, the X-ray opaque marker 5 is configured by winding a thin wire such as gold, silver, platinum, or tungsten, but the form is not particularly limited, and for example, a sheet shape, a band shape, or a C-shape. It may be a ring.
[0038]
Further, it is preferable that a layer (not shown) made of a hydrophilic polymer material having lubricity in a wet state is formed on the outer peripheral surface of the catheter body 2. Thereby, when inserting the catheter 1, a friction is reduced, the insertion can be performed smoothly, and operativity and safety improve.
[0039]
The catheter body 2 as described above is used by being inserted into a guiding catheter (not shown) or a contrast catheter as necessary when inserted into a blood vessel.
[0040]
As shown in FIG. 1, a hub 4 is fixed to the proximal end portion of the catheter body 2 in a liquid-tight manner, for example. The lumen of the hub 4 communicates with the proximal end of the lumen 23 of the catheter body 2.
[0041]
The hub 4 functions as an insertion port of the guide wire 100 into the lumen 23 of the catheter body 2, an injection port of a liquid such as a chemical solution into the lumen 23, and the like. The hub 4 also functions as a gripping part when operating the catheter body 2.
The constituent material of the hub 4 is not particularly limited. For example, a resin material such as polyvinyl chloride, polyethylene, polypropylene, polycarbonate, polymethyl methacrylate, acrylonitrile-styrene-butadiene copolymer, stainless steel, titanium, or the like. It can be composed of various metal materials.
[0042]
The guide wire 100 is a wire having bending elasticity, and its constituent material is not particularly limited. For example, various types of plastics, pseudo-elastic (superelastic) alloys (eg, Ni-Ti alloys), stainless steel, and the like. Metal materials can be used.
[0043]
The entire surface or part of the guide wire 100 is preferably subjected to a treatment for imparting lubricity.
[0044]
The distal end portion 101 of the guide wire 100 has a curved shape in a natural state (a state in which no external force is applied). When selecting a blood vessel or the like, the protrusion length of the distal end portion 101 of the guide wire 100 from the distal end opening of the catheter body 2 is changed according to the situation by relatively moving the guide wire 100 and the catheter 1 forward and backward. Let
[0045]
That is, using the curvature of the distal end portion 101 of the guide wire 100, the direction of the curvature is changed by rotation in the direction of the target blood vessel, and the guide wire 100 is inserted into the target blood vessel. At this time, the portion of the guide wire 100 protruding from the catheter body 2 is often greatly curved. The position of the groove 21 of the catheter body 2 is rotated along the curved guide wire 100 so that the groove 21 comes to the concave side (inner side of the curve) of the guide wire 100. As a result, an excessive force is not applied to the bending of the guide wire 100, so that the guide wire 100 does not come off from the target blood vessel.
[0046]
As described above, in the present invention, by combining the rotation of the catheter 1 in addition to the relative advance / retreat operation of the guide wire 100 and the catheter 1, more various curves of the distal end portion of the guide wire 100 and the catheter body 2 are obtained. A state is obtained. In the present invention, by utilizing these various curved states, the guide wire 100 and the catheter main body 2 can be advanced smoothly and easily in a desired direction by flexibly dealing with complicated blood vessel shapes such as blood vessel bending and branching. be able to.
[0047]
Next, an example of how to use the catheter 1 will be described.
A guide wire 100 is inserted into the lumen 23 of the catheter body 2 in advance.
[0048]
Next, a guiding catheter (not shown) or a contrast catheter is percutaneously inserted to the vicinity of a target site (hereinafter referred to as a target site) of the blood vessel using a guide wire (not shown) by the Seldinger method or the like.
[0049]
Next, after extracting the guide wire, the catheter body 2 of the catheter 1 is inserted into the guiding catheter (contrast catheter) with a new guide wire 100 in advance, and the distal end portion is inserted to the target site.
[0050]
When the distal end of the catheter body 2 reaches the target site, the guide wire 100 is pulled out from the catheter body 2.
[0051]
Thereafter, an injection device such as a syringe is connected to the hub 4 to inject a contrast medium or a chemical solution. Thereby, the contrast agent or the drug solution is sequentially injected into the blood vessel from the distal end of the catheter body 2 through the lumen of the hub 4 and the lumen 23 of the catheter body 2.
[0052]
After the above procedure is completed, the catheter body 2 is extracted from the blood vessel together with the guiding catheter (contrast catheter).
[0053]
Second Embodiment
FIG. 4 is a perspective view showing a catheter body in the second embodiment of the catheter of the present invention. In the following description, the right side in FIG. 4 is referred to as “base end” and the left side is referred to as “tip”. Further, in FIG. 4, the length of the catheter body 2 a in the longitudinal direction is shortened for easy understanding.
[0054]
Hereinafter, the second embodiment of the catheter of the present invention will be described with reference to this drawing, but the description will focus on the differences from the above-described embodiment, and the description of the same matters will be omitted.
[0055]
The present embodiment is the same as the first embodiment except that the depth (maximum depth) of the groove 21 of the catheter body 2a is continuously decreased (gradually decreased) in the proximal direction.
[0056]
In the catheter main body 2a of the present embodiment, the depth of the groove 21 is relatively deeper toward the distal end side, and is relatively shallow toward the proximal end side. As a result, the catheter body 2a has a smaller and more flexible bending rigidity when it is bent so that the formation portion of the groove 21 is on the inner side as it goes to the distal end side, and the groove 21 is moved toward the proximal end side. There is no difference in the easiness of bending between the direction inside the curve and the other directions. As a result, better followability can be obtained on the distal end side of the catheter body 2, and more excellent and excellent torque transmission and pushability can be obtained on the proximal end side of the catheter body 2 a. That is, in this embodiment, more excellent operability can be obtained.
[0057]
Note that the depth of the groove 21 of the catheter body 2a may be constant along the longitudinal direction. Further, the depth of the groove 21 may be zero in the middle of the catheter body 2a. That is, the groove 21 may be eliminated in the middle of the catheter body 2a.
[0058]
<Third Embodiment>
FIG. 5 is a perspective view showing a catheter body in the third embodiment of the catheter of the present invention. In the following description, the right side in FIG. 5 is referred to as “base end”, and the left side is referred to as “tip”. In FIG. 5, the length of the catheter body 2b in the longitudinal direction is shortened for easy understanding.
[0059]
Hereinafter, a third embodiment of the catheter of the present invention will be described with reference to this figure, but the description will focus on differences from the above-described embodiment, and the description of the same matters will be omitted.
[0060]
This embodiment is the same as the first embodiment except that the depth (maximum depth) of the groove 21 of the catheter body 2b is gradually reduced (gradually reduced) toward the proximal direction.
[0061]
In the catheter main body 2b of the present embodiment, the depth of the groove 21 decreases in a plurality of stages (three stages in the illustrated configuration) toward the proximal direction. That is, the depth of the groove 21 is relatively deep on the distal end side of the catheter body 2b, the depth of the groove 21 is relatively shallow on the proximal end side, and the depth of the groove is medium in the middle portion thereof. Thereby, in this embodiment, the effect similar to the said 2nd Embodiment is acquired.
[0062]
Moreover, since the part where the depth of the groove | channel 21 is the same has the same softness | flexibility, the catheter suitable for various procedures is easily obtained by changing suitably the depth and length of the groove | channel 21 according to the bending condition of the target site | part. be able to.
[0063]
<Fourth embodiment>
6 is a plan view showing a fourth embodiment of the catheter of the present invention, FIG. 7 is a cross-sectional view taken along the line YY in FIG. 6 (transverse cross-sectional view), and FIG. 8 is a line ZZ in FIG. It is sectional drawing (transverse sectional view). In the following description, the right side in FIG. 6 is referred to as “base end” and the left side is referred to as “tip”.
[0064]
Hereinafter, the fourth embodiment of the catheter of the present invention will be described with reference to these drawings, but the description will focus on differences from the above-described embodiment, and the description of the same matters will be omitted.
[0065]
The present embodiment is the above except that it has a tube member 3 that covers the outer periphery of the catheter body 2 and that a plurality of slits 24 are formed in the tube wall of the distal end portion of the catheter body 2. This is the same as in the first embodiment.
[0066]
As shown in FIGS. 6 and 7, the catheter 1 ′ of the present embodiment is provided with a tubular (cylindrical) tube member 3 that covers the outer circumference of the catheter body 2 over the entire length thereof.
[0067]
The tube member 3 is made of a synthetic resin material and has flexibility. Examples of the synthetic resin material constituting the tube member 3 include polypropylene, polyethylene, polyolefins such as ethylene-vinyl acetate copolymer, polyesters such as polyethylene terephthalate (PET) and polybutylene terephthalate (PBT), polytetrafluoroethylene, Fluorine resin such as ethylene-tetrafluoroethylene copolymer, polystyrene resin, polyamide, polyurethane, polyimide and various flexible resins, polyamide elastomer, polyester elastomer, polyurethane elastomer, polystyrene elastomer, fluorine elastomer, or A combination of two or more of these (for example, a multi-layer laminate or a polymer blend) may be used. Thus, since the tube member 3 is formed of a material that is more flexible than the catheter body 2, the resistance of the tube member 3 can be substantially ignored when the catheter body 2 is bent.
[0068]
In the present embodiment, the outer periphery is covered with such a flexible tube member 3, whereby stimulation to the inner wall of the blood vessel can be further reduced and safety is higher.
[0069]
In the catheter 1 ′, the tube member 3 is provided so as to extend further in the distal direction than the distal end 25 of the catheter body 2. That is, as shown in FIG. 8, the distal end portion of the catheter 1 ′ is constituted by only the tube member 3 with the catheter body 2 missing. As a result, the distal end portion of the catheter 1 ′ is more flexible, can further reduce irritation to the inner wall of the blood vessel, and can obtain higher safety. Further, the followability can be further improved. The length of the missing portion of the catheter body 2 at the distal end is not limited, but is preferably 2 to 300 mm.
[0070]
The outer surface of the tube member 3 is preferably covered with a lubricating layer (not shown) made of a hydrophilic (or water-soluble) polymer substance. As a result, when the outer surface of the tube member 3 comes into contact with blood, physiological saline, or the like, the friction coefficient is reduced, lubricity is imparted, and the slidability of the catheter 1 ′ is further improved, resulting in torque. Transmission, pushability and safety are further enhanced.
[0071]
The tube member 3 is not limited to covering the entire length of the catheter body 2 but may be provided so as to cover the outer periphery of at least the distal end portion of the catheter body 2. Even in this case, the same effect can be obtained.
[0072]
As shown in FIG. 6, in the present embodiment, a plurality of slits 24 are formed in a predetermined range of the tube wall on the distal end side of the catheter body 2. In the illustrated configuration, the slits 24 are formed so as to extend in a direction substantially orthogonal to the longitudinal direction of the catheter body 2, and are arranged substantially parallel to each other at a predetermined interval. At the site where the slits 24 are formed, the flexibility of the catheter body 2 is increased, and thus the catheter 1 ′ can be further improved in followability.
[0073]
In addition, the provision of the tube member 3 prevents the contrast medium or the chemical liquid injected into the lumen 23 from leaking from the slit 24.
[0074]
Further, instead of the plurality of slits 24, a spiral slit can be formed on the tube wall at the distal end portion of the catheter body 2, and the same effect can be obtained. In this case, it is preferable to form the spiral pitch (interval) of the spiral slit so as to narrow continuously or stepwise as it goes in the tip direction. Thereby, the part of the front end side in the formation part of a helical slit can be made more flexible.
[0075]
Further, the slit may be formed so as to extend in the longitudinal direction of the catheter body 2.
[0076]
The catheter of the present invention has been described above with respect to the illustrated embodiment. However, the present invention is not limited to this, and each part constituting the catheter can be replaced with an arbitrary structure that can exhibit the same function. can do. Moreover, arbitrary components may be added.
[0077]
【The invention's effect】
As described above, according to the present invention, it is possible to obtain a catheter that has a simple structure, excellent torque transmission performance and pushability, and excellent followability, and has excellent operability.
[0078]
In addition, when the catheter body has a portion in which the depth of the groove of the catheter body decreases continuously or stepwise toward the proximal direction, torque transmission performance, pushability, and followability can be further improved. .
[0079]
Moreover, when the groove | channel of a catheter main body is formed by plastically deforming the tube wall of a catheter main body, manufacture is easy and the said effect can be achieved at a lower manufacturing cost.
[0080]
Further, when a tube member that is made of a synthetic resin material and covers the outer periphery of at least the distal end portion of the catheter body is provided, higher safety can be obtained.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a first embodiment of the catheter of the present invention (a state where a guide wire is inserted through a lumen).
FIG. 2 is a cross-sectional view (cross-sectional view) taken along line XX in FIG.
FIG. 3 is a perspective view of a catheter body in the catheter shown in FIG.
FIG. 4 is a perspective view showing a catheter body in a second embodiment of the catheter of the present invention.
FIG. 5 is a perspective view showing a catheter body in a third embodiment of the catheter of the present invention.
FIG. 6 is a plan view showing a fourth embodiment of the catheter of the present invention.
7 is a cross-sectional view (cross-sectional view) taken along line YY in FIG.
8 is a cross-sectional view (transverse cross-sectional view) taken along line ZZ in FIG. 6. FIG.
FIG. 9 is a graph showing measured data of load and deflection in a three-point bending test of a metal tube on the vertical axis and the horizontal axis, respectively.
[Explanation of symbols]
1, 1 'catheter
2, 2a, 2b Catheter body
21 groove
22 Protrusion
23 lumens
24 slits
25 Tip
3 Tube members
4 Hub
5 X-ray opaque marker
100 guide wire
101 Tip

Claims (9)

The outer periphery of at least the tip end portion of the tubular catheter body and the catheter body made of a metal coated, and a tube member made of a synthetic resin material which is fixed relative to the outer peripheral, the tip A catheter used with a curved guide wire having a curved shape ,
The catheter body has one groove formed along the longitudinal direction so that the tube wall is depressed on the outer peripheral surface of at least the distal end portion thereof, and the wall thickness of the tube wall of the catheter body is , Ri substantially constant der over the entire circumference including the formation portion of the groove, as the bending stiffness when forming part of said groove is curved so that the inner side, forming part of the groove is outside The bending stiffness when bent and the bending stiffness when bent so that the portion different from the groove forming portion by 90 ° is inside or outside is smaller than any bending stiffness.
The tube member is provided so as to extend further in the distal direction than the distal end of the catheter body, whereby the distal end portion of the catheter has a defect in the catheter body . The catheter according to claim 1, wherein the catheter body has a length of 80 to 200 cm and an average outer diameter of 0.2 to 5 mm. The catheter according to claim 1 or 2, wherein a length of a portion of the catheter body at the distal end portion of the catheter that is deficient is 2 to 300 mm. 4. The groove according to claim 1, wherein the groove is formed by plastic deformation and plastic deformation of a tube wall of the catheter body having an unprocessed, circular cross section in which the groove is not yet formed. The catheter according to 1. In the plastic working, the raw catheter body is inserted into a mold having a semicircular cross-sectional shape having an inner surface with the same curvature as the outer peripheral surface of the raw catheter body, and faces the mold In a position, a jig having a projection corresponding to the groove is provided, and the jig is pressed against the unprocessed catheter body, and the unprocessed between the mold and the jig. The catheter according to claim 4, wherein the catheter body is relatively moved so as to be pulled out in the longitudinal direction, and the groove is gradually formed along the longitudinal direction. The catheter according to any one of claims 1 to 5, further comprising a portion in which the depth of the groove decreases continuously or stepwise toward the proximal direction. The catheter according to any one of claims 1 to 6 , wherein the catheter body is made of stainless steel or a pseudoelastic alloy. A plurality of slits are formed in the tube wall of the distal portion of the catheter body, wherein the slit is one of the catheter to substantially claims 1 are formed to extend in a direction perpendicular to the longitudinal direction of the main body 7 The catheter according to 1. Said catheter body distal end portions spiral slits in the tube wall of the formation, the pitch of the helix of the slits toward the distal direction, of the claims 1 to 8 which is continuously or stepwise narrowed The catheter according to any one of the above.

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