JP2012020068A - Tube and catheter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tube having an improved breaking load or the like by providing the tube with parts having different thicknesses and thus increasing cross section of the tube.SOLUTION: An outer tube 11 is formed by integrating a comparatively thick part 13K and a comparatively thin part 13N, so as to have various thicknesses instead of a uniform thickness.

Description

  The present invention relates to a tube and a catheter.

  A catheter is inserted into a body vessel and is widely used for delivering a fluid inside or outside the body or for expanding a stricture formed in the body vessel. Thus, for example, a catheter moves within a complex, narrow vessel within the body. The catheter must then include a shaft tube that is both flexible and strong.

  The breaking strength of the shaft tube depends on the cross-sectional area of the shaft tube itself. Therefore, when the outer diameter is increased or the inner diameter is reduced in the shaft tube, the cross-sectional area of the shaft tube increases, which is preferable.

  However, if the outer diameter of the shaft tube is excessively enlarged, the contour (profile) becomes large, and the flexibility of the shaft tube is impaired. Furthermore, if the less invasiveness to the living body is considered, the outer diameter of the shaft tube must be small. Further, when the inner diameter of the shaft tube is enlarged, it is difficult to maintain the lumen required for delivering the fluid.

  By the way, in order to engage the inner member and the outer member included in the catheter described in Patent Document 1, for example, one surface engages with the other surface on the outer surface of the inner member and the inner surface of the outer member. Including bumps. In this catheter, while the inner member and the outer member are engaged, the fluid path is maintained and the transmission of force over the shaft tube is improved.

Special table 2009-528901

  However, the shaft tube in Patent Document 1 is based on the relationship between the inner member and the outer member, and does not describe the breaking load of a single member.

  The present invention has been made to solve the above problems. And the objective is to provide the tube which included the site | part from which thickness differs, increased the cross-sectional area of the tube by this, and improved the breaking load etc.

  The treatment catheter includes a tube having a lumen. And in this tube, the wall part surrounding a lumen | bore is formed of the collection of the site | parts from which thickness differs.

  Moreover, in the cross section which cross | intersects the axial direction of a tube, it is preferable that the line shown by the inner wall face of a wall part contains an inflexion point.

  Moreover, it is preferable when one site | part among the site | parts from which thickness differs differs with respect to the inner wall surface of the wall part formed in the other site | part.

  Moreover, it is preferable that at least one or more ridges are included in the cross section intersecting the axial direction of the tube.

  Further, it is preferable that the width of the ridge is constant or changes in the axial direction of the tube.

  Moreover, it is preferable that the bulge length of the bulge is constant or changes in the axial direction of the tube.

  Further, it is preferable that the ridge extends over at least a part in the axial direction.

  Further, it is preferable that the ridge is tapered.

  Moreover, in the cross section which cross | intersects the axial direction of a tube, it is preferable that the line shown by the taper protrusion contains at least one of a curve and a straight line.

  Further, the tapering ridge is preferably a shape including a polygonal column shape, a semi-cylindrical shape, a polygonal pyramid shape, a conical shape, a polygonal truncated cone shape, or a truncated cone shape.

  Moreover, the catheter for lesion treatment containing the above tubes is also this invention. The catheter is preferably a balloon catheter or a stent delivery catheter.

  The tube of the present invention includes a portion having a different thickness so that the cross-sectional area can be increased. As a result, the breaking load or the like can be increased without changing the tube profile.

FIG. 3 is a perspective view of an outer tube. These are cross-sectional views of an outer tube. These are cross-sectional views of an outer tube. FIG. 3 is a perspective view of an outer tube. FIG. 3 is a perspective view of an outer tube. These are cross-sectional views of an outer tube. These are cross-sectional views of an outer tube. These are tables summarizing the results of numerical examples. These are cross-sectional views of an outer tube. These are cross-sectional views of an outer tube. FIG. 2 is a side view of a fast exchange type balloon catheter. FIG. 3 is a side view of an over-the-wire type balloon catheter. FIG. 2 is a side view of a fast exchange type balloon stent delivery catheter. FIG. 3 is a side view of an over-the-wire stent delivery balloon catheter.

[Embodiment 1]
The following describes one embodiment with reference to the drawings. For convenience, hatching, member codes, and the like may be omitted, but in such a case, other drawings are referred to.

<About the catheter>
The catheter will be described below. Examples of the catheter include a high-speed exchange type balloon catheter 49 as shown in FIG. 11 or an over-the-wire type balloon catheter 49 as shown in FIG. Such a balloon catheter 49 includes, for example, a lumen 51 for attaching a balloon 51 to the distal end side of the outer tube 11 and flowing pressure fluid through the balloon 51, and further includes a lumen for passing a guide wire (note that The tube through which the guide wire is passed is called the inner tube 21, and the tube surrounding the inner tube 21 is called the outer tube 11).

  The catheter 49 is not limited to the balloon catheter 49. For example, as shown in FIG. 13, a high-speed exchange type stent delivery catheter 49 in which a balloon 51 is covered with a stent 52 or an over-the-wire type in which a balloon 51 is covered with a stent 52 as shown in FIG. A stent delivery catheter 49 is an example of the catheter 49.

  In short, for example, a catheter 49 that is inserted into a blood vessel, esophagus, trachea, urethra, or bile duct in the body and used to deliver fluid inside or outside the body, or to expand inside the body and maintain a body cavity. If it is, it will not specifically limit (In addition, such a catheter 49 is called the catheter 49 for treatment of a lesion etc.).

  11 to 14, the member number 41 indicates the hub 41 and the member number 42 indicates the manifold 42 (in the catheter 49, the side where the hub 41 or the manifold 42 is located is the proximal end side, and this proximal end. The side opposite to the side is referred to as the distal end side). Further, when the catheter 49 includes a connection tube, the member number 31 indicates the connection tube 31.

<Outer tube>
FIG. 1 is a perspective view showing an outer tube [tube] 11 included in the catheter 49. In addition, the figure which expanded the cross-section part of the outer tube 11 in FIG. 1 turns into a cross-sectional view of FIG. {Note that this cross-section is relative to the axial direction that is the longitudinal direction of the outer tube 11 (and thus the catheter 49). Cross section (transverse section) such as vertical}.

  As shown in FIGS. 1 and 2, the outer tube 11 is a tube including a lumen (hollow) 12. And the wall part 13 which is the part surrounding this lumen | bore 12 is not formed by fixed thickness. That is, the wall portion 13 is formed of a group of portions having different thicknesses.

  More specifically, for example, in the case of the outer tube 11 as shown in FIGS. 1 and 2, a relatively thick part 13K (part having a thickness K1) and a comparatively thin part 13N (thickness). As a result, the outer tube 11 having a changed thickness is completed instead of a constant thickness.

  Specifically, among the portions 13K and 13N that are portions having different thicknesses, the portion 13K that is one portion is the inner wall surface 14A of the wall portion 13 that is formed by the portion 13N that is the other portion. On the other hand, it becomes a bump 15 (note that this bump (protrusion) 15 extends over the entire area in the axial direction of the outer tube 11).

  If it is in this way, on the outline (on the profile), the outer tube 11 will be cylindrical. However, since the ridges 15 are formed on the inner wall surface 14A of the wall 13 that is the inside of the outer tube 11, the surface shape of the lumen 12 in the outer tube 11 is not formed only by a curved surface (note that the shape of the ridges 15 is It can be observed with a micro digital high scope, and the dimensions of the bumps 15 can be confirmed by measuring an image with the micro digital high scope).

  That is, in the outer tube 11 shown in FIGS. 1 and 2, the line indicated by the inner wall surface 14 </ b> A of the wall portion 13 includes an inflection point in the cross section that intersects the axial direction of the outer tube 11. It will be.

  Further, such an outer tube 11 has an increased strength as compared with a tube formed of a wall portion having a certain thickness (for example, only the thickness N1 of the thinner portion 13N), and is also axial. Also increases the transmission force and rigidity.

  For example, the breaking strength of the outer tube 11 having various thicknesses is stronger than the breaking strength of the outer tube having only a certain thickness. This is because the thick portion of the wall portion 13 contributes greatly to the breaking strength of the outer tube 11.

  On the other hand, the flexibility of the outer tube 11 including the ridges 15 is not much different from the flexibility of the outer tube having only a certain thickness. For example, the bending rigidity of the outer tube 11 having various thicknesses is not much different from the bending rigidity of the outer tube having only a certain thickness. This is because, for the flexibility of the outer tube 11, the contribution of the thin portion of the wall portion 13 is large.

  For example, as shown in FIG. 2, four ridges 15 are included in the cross section intersecting the axial direction of the outer tube 11, but the present invention is not limited to this. That is, the number of the bumps 15 may be 1 to 3, or may be 5 or more as shown in FIG. The point is that the thickness of the outer tube 11 varies only with at least one ridge 15.

  Further, the width of the ridge 15 (width length W1) may be constant over the entire length of the ridge 15 (the length of the ridge 15 over the entire axial direction of the outer tube 11), as shown in FIG. , May be different. That is, as shown in FIG. 4, the outer tube 11 may include a ridge 15 including a width length W1 and a width length W11 different from the width length W1. Not only two types but also three or more other types). Moreover, as shown in FIG. 4, the width | variety length may change continuously by the side surface of the protrusion 15 being formed in a curved surface (refer the dashed-dotted line circle part).

  Further, as shown in FIG. 4, the bulge length (bulge length D <b> 1) of the bulge 15 may be constant or different over the entire length of the bulge 15. That is, as shown in FIG. 4, a ridge 15 including a ridge length D1 and a ridge length D11 different from the ridge length D1 may be included in the outer tube 11 (note that the types of ridge length are Not only two types but also three or more other types). Moreover, as shown in FIG. 4, the ridge length may change continuously by the top | upper surface of the ridge 15 being formed in a curved surface (refer to a dashed-two dotted line circle part).

  Further, as shown in FIG. 4, the ridges 15 do not have to extend over the entire area in the axial direction of the outer tube 11, and the ridges 15 may extend over only a part as shown in FIG. It goes without saying that the ridge 15 extending over a portion of the tube 11 in the axial direction may change at least one of the width length and the ridge length).

  Thus, even if the ridges 15 are only in a part of the entire length of the outer tube 11, the strength and the like of the outer tube 11 are improved compared to the strength and the like of the outer tube having a certain thickness. (In short, the ridges 15 may extend over at least a part of the outer tube 11 in the axial direction).

  Further, the shape of the ridge 15 is not limited to a shape including a polygonal column shape as shown in FIGS. 2 and 3. For example, as shown in FIGS. 6 and 7, the ridge 15 may have a tapered shape.

  For example, the ridge 15 may have a shape including a semi-cylindrical shape. Specifically, as shown in FIG. 6, in the cross section intersecting the axial direction of the outer tube 11, the line indicated by the tapered ridge 15 includes a curved line (specifically, in the cross-sectional view, A taper-shaped semi-cylindrical ridge 15 may be formed because the line indicating the top surface includes a curved line).

  Further, the ridges 15 may have a shape including a polygonal pyramid shape. More specifically, as shown in FIG. 7, in the cross section intersecting the axial direction of the outer tube 11, the line indicated by the tapered ridge 15 includes an inclined straight line. As the lines indicating the side surfaces are inclined so as to approach each other, a tapered polygonal cone-shaped ridge 15 may be formed.

  The ridges 15 are not limited to a shape including a polygonal column shape, a semi-cylindrical shape, or a polygonal pyramid shape, and may be, for example, a conical shape, a polygonal frustum shape, or a shape including a truncated cone shape.

  Moreover, the material of the outer tube 11 is not specifically limited, For example, polyolefin, polyolefin elastomer, polyester, polyester elastomer, polyamide, polyamide elastomer, polyurethane, or polyurethane elastomer is mentioned.

  And such resin changes to the tube-shaped outer tube 11 by the extrusion molding which used the metal mold | die, for example. With such extrusion molding, the outer tube 11 having a different thickness can be easily formed.

  Further, in order to change the wall thickness of the wall portion 13 of the outer tube 11, the same material as the material of the outer tube 11 or another material may be attached to the outside of the outer tube 11. For connection of another member to the outer tube 11, for example, adhesion using an adhesive or heat welding by heat melting is used.

<About connection tube>
The material of the connection tube 31 is not particularly limited, and examples thereof include polyolefin, polyolefin elastomer, polyester, polyester elastomer, polyamide, polyamide elastomer, polyurethane, or polyurethane elastomer.

  In addition, in order to improve operativity as the connection tube 31, a metal tube may be connected to the proximal end side (side near the hub 41 etc.), when larger rigidity is required. The metal tube may be made of stainless steel or other metal and may have an antithrombotic coating on the outside thereof.

<Inner tube>
The material of the inner tube 21 is not particularly limited, and examples thereof include polyethylene, polyolefin, polyolefin elastomer, polyester, polyester elastomer, polyamide, polyamide elastomer, polyurethane, or polyurethane elastomer.

  The inner side (lumen) of the inner tube 21 serves as a guide wire lumen. Therefore, in consideration of the slidability of the guide wire, it is preferable that the inner tube 21 is formed of polyethylene, particularly high-density polyethylene.

  The inner tube 21 may have a multilayer structure. In the case of the inner tube 21 having such a multilayer structure, in order to ensure the slidability of the guide wire, the innermost layer is formed of high-density polyethylene, and the outermost layer is a material that can be bonded or fused to the balloon 51 or the outer tube 11. May be formed.

  More preferably, almost the entire area of the inner tube 21 is formed in a single layer structure, and only the portion connected to the balloon 51 and the outer tube 11 may be formed in a multilayer structure.

  In order to further improve the slidability of the guide wire, a lubricious coating such as silicon or polytetrafluoroethylene may be applied to the inner surface of the inner tube 21.

<About balloon>
The material of the balloon 51 is not particularly limited, and examples thereof include polyolefin, for example, polyolefin elastomer, polyester, polyester elastomer, polyamide, polyamide elastomer, polyurethane, or polyurethane elastomer (specifically, the material of the balloon 51 is biaxially stretched. It is preferable if possible.

  In addition, when the balloon 51 must expand the stent 52 sufficiently, the material of the balloon 51 is preferably a thin and flexible material while having a relatively high pressure strength. For example, polyester, polyester elastomer, polyamide, or polyamide elastomer can be used as the material of the balloon 51.

<About connection between various members>
The method of connecting at least two members of the outer tube 11, the connection tube 31, the inner tube 21, and the balloon 51 is not particularly limited. For example, the connection method of adhesion | attachment by an adhesive agent or the melt | fusion by heat | fever is mentioned.

  Further, the composition and chemical structure relating to the adhesive, and the curing type of the adhesive are not particularly limited. In view of the composition and chemical structure related to the adhesive, urethane type, silicon type, epoxy type and cyanoacrylate type adhesives are preferred. From the viewpoint of the curing type of the adhesive, a two-component mixed type, UV curable type, water absorption curable type, heat curable type, or radiation curable type adhesive is preferable.

<About hub or manifold>
The material forming the hub or the manifold is not particularly limited, and examples thereof include polycarbonate, polyamide, polyurethane, polysulfone, polyarylate, styrene-butadiene copolymer, and polyolefin.

<Details for each type of catheter>
In the over-the-wire type balloon catheter 49, the balloon 51 is attached to the outer tube 11 on the distal end side. Then, the inner tube 21 including the guide wire lumen is disposed inside the balloon 51 and the outer tube 11 (the inner tube 21 is disposed over the entire length of the outer tube 11).

  In the fast exchange type balloon catheter 49, the distal end side of the first connection tube 31 is connected to the proximal end side of the balloon 51, and a guide wire lumen is provided inside the balloon 51 and the first connection tube 31. The inner tube 21 which has is arrange | positioned. Further, the distal end side of the inner tube 21 and the distal end side of the balloon 51 are bonded, the proximal end side of the first connection tube 31 and the distal end of the outer tube 11 are connected, and the outer tube 11 Are connected to the distal end side of the second connection tube 31. In the longitudinal direction of the catheter 49, the order of the outer tube 11 and the first and second connection tubes 31 is not particularly limited.

  In the stent delivery catheter 49, the stent 52 (for example, the body cavity opening stent 52) is preferably a balloon expandable stent 52. And the material of the stent 52 is not specifically limited, For example, stainless steel, such as SUS316L, or a cobalt chromium alloy is mentioned. In addition, the design of the stent 52 is not limited at all.

  The stent 52 is disposed so as to cover the balloon 51. More specifically, for example, several folded balloons 51 are wound along the inner tube 21 around the axial direction of the catheter 49. And the stent 52 is arrange | positioned so that this balloon 51 may be covered.

  There are many ways to wind the balloon 51. For example, if there are two or more balloons 51, a method of winding (S wrap) in which the folded balloon 51 is wound in the same rotational direction can be mentioned. In addition, if there are two or more balloons 51, the folded balloons 51 may be wound in opposite directions (C wrap) (however, if there are three or more balloons 51, they are wound in the same direction). Winding is often used).

  When two or more balloons 51 are folded and the balloons 51 are wound around the axial direction of the catheter 49, the position where the stent 52 is attached (reduced in diameter) is a straight tube in the balloon 51. It is preferable to arrange on the part.

<About hydrophilic coating>
The outer surface of the catheter 49 is preferably provided with a hydrophilic coating to facilitate insertion into a blood vessel or guide catheter.

  Further, it is preferable that a hydrophilic coating exhibiting lubricity is applied to at least a part of the shaft tube that contacts the blood of the catheter 49 when it contacts the blood.

  In addition, the kind of hydrophilic coating is not specifically limited, For example, hydrophilic polymers, such as polyethyleneglycol, polyacrylamide, or polyvinylpyrrolidone, are mentioned. Further, the coating method is not particularly limited.

  In the stent delivery catheter 49, when the hydrophilic coating is applied to the surface of the balloon 51, the stent 52 is easily dropped. Therefore, it is preferable that the surface of the balloon 51 is not provided with a hydrophilic coating. Further, only the hydrophilic coating on the balloon 51 is removed, and the balloon 51 is covered with a material layer having a high friction coefficient such as urethane or rubber so that the stent 52 does not fall off the balloon 51. Good.

  An example regarding the contents described above will be specifically shown. However, it is not limited to this.

(Example 1 [EX1])
As shown in FIG. 7, an outer tube 11 having four ridges (protrusions) 15 inside is formed by extrusion molding using a polyamide elastomer (trade name: PEBAX7233SA01, manufactured by Arkema).

  And this outer tube 11 is cut | disconnected so that the circumferential direction may be followed, and shape observation is carried out with a micro digital high scope. As a result, this outer tube 11 has an inner diameter of 0.58 mm, an outer diameter of 0.71 mm, a width W1 of the ridge 15 of 0.10 mm (however, an average value), and a ridge length D1 of the ridge 15 of 0.12 mm (however, Average value). In addition, compared with the cross-sectional area of the outer tube in the following comparative example, the cross-sectional area of the outer tube 11 of Example 1 is about 120%.

(Comparative Example [CEX])
An outer tube that does not include any ridges is taken as a comparative example. The outer tube as a comparative example is formed by extrusion molding using a polyamide elastomer (trade name: PEBAX7233SA01, manufactured by Arkema Co.). The outer tube of this comparative example has an inner diameter of 0.58 mm and an outer diameter of 0.71 mm.

(Tensile test)
Both ends of the outer tube are chucked so that the distance between the test pieces is 10 mm. The outer tube 11 is pulled by the tensile tester. The test speed is 200 mm / min. By this test, the load when the outer tube 11 breaks (break load [N]) is measured.

(Three point bending test)
The lower part of the outer tube 11 is supported at two points (distance between fulcrums: 12 mm). And one point is pushed in from the upper part of the outer tube 11 (test speed: 50 mm / min), and the load (bending rigidity [N]) at the time of pushing 1 mm is measured.

(Evaluation results)
The evaluation results are as shown in the table of FIG. And from this result, the breaking load of the outer tube 11 (Example 1) including the ridges 15 on the inner side was improved as compared with the breaking strength of the outer tube (Comparative Example) not including any ridges. However, the bending rigidity of the outer tube 11 of Example 1 was equivalent to the bending rigidity of the outer tube of the comparative example.

[Other embodiments]
The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

  For example, the ridges 15 may be linear or point-like. Further, as shown in FIGS. 9 and 10, the outer tube 11 may not be formed with the ridges 15 on the wall surface (the inner wall surface 14 </ b> A and the outer wall surface 14 </ b> B) of the wall portion 13.

  More specifically, in the cross section of the outer tube 11 (at least one of the vertical cross section and the horizontal cross section), a portion 13K having a different thickness with respect to the portion 13N including the reference thickness (rather than the thickness of the reference portion 13N). The portion 13K) having a large thickness may be the outer tube 11 including at least one or more.

  Even such an outer tube 11 has the above-described effects due to the difference in thickness.

11 Outer tube [Tube]
DESCRIPTION OF SYMBOLS 12 Lumen 13 Wall part 14A Inner wall surface 14B Outer wall surface 15 Bump 21 Inner tube 31 Connection tube 41 Hub 42 Manifold 49 Catheter 51 Balloon 52 Stent

Claims (12)

A tube with a lumen contained in a catheter for lesion treatment;
The wall surrounding the lumen is a tube formed by a collection of parts having different thicknesses.   The tube according to claim 1, wherein a line indicated by an inner wall surface of the wall portion includes an inflection point in a cross section intersecting with an axial direction of the tube.   The tube according to claim 1 or 2, wherein one of the portions having different thicknesses is raised with respect to the inner wall surface of the wall portion formed at the other portion.   The tube according to claim 3, wherein at least one of the ridges is included in a cross section intersecting the axial direction of the tube.   The tube according to any one of claims 3 and 4, wherein a width of the ridge is constant or changes in an axial direction of the tube.   The tube according to any one of claims 3 to 5, wherein a protruding length of the protruding portion is constant or changes in an axial direction of the tube.   The tube according to any one of claims 3 to 6, wherein the ridge extends over at least a part in the axial direction.   The tube according to any one of claims 3 to 7, wherein the ridge is tapered.   The tube according to claim 8, wherein a line indicated by the tapered ridge in a cross section intersecting with an axial direction of the tube includes at least one of a curved line and a straight line.   10. The tube according to claim 8, wherein the tapering ridge has a shape including a polygonal column shape, a semi-cylindrical shape, a polygonal pyramid shape, a conical shape, a polygonal frustum shape, or a truncated cone shape.   The catheter for lesion treatment containing the tube of any one of Claims 1-10.   The catheter according to claim 11, which is a balloon catheter or a stent delivery catheter.

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