JP2018075470A - catheter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a catheter with which the state of a shaft within a blood vessel can be checked by a simple constitution.SOLUTION: A balloon catheter 100 comprises: shafts 130 and 140; a balloon 120 provided on the distal side of the shafts 130 and 140; and a core metal member 170 provided inside the shafts 130 and 140 in the longitudinal direction of the shafts 130 and 140. Furthermore, the core metal member 170 is coated with X-ray impermeable material such as Au, Pt, Ir, and W.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a catheter having a cored bar member.

  Among catheters, for example, a balloon catheter is widely used as a medical instrument for expanding blood vessel stenosis and improving blood flow on the peripheral side of a blood vessel when stenosis occurs in a blood vessel such as a blood vessel. When performing a procedure using a balloon catheter, first, the balloon catheter is inserted into the blood vessel so that the balloon matches the stenotic site. Next, the stenotic site is expanded by injecting a pressurized fluid into the balloon to expand the balloon. After performing dilatation treatment, the balloon is deflated and the balloon catheter is removed from the blood vessel.

  In the balloon catheter, basically, a hub, a proximal shaft, and a distal shaft are arranged in this order from the proximal side (hand side), and a balloon is arranged near the tip on the distal side of the distal shaft. The proxy shaft is composed of an outer tube, and the distal shaft has a double tube structure composed of an outer tube and an inner tube. The outer tube plays a role of feeding fluid into the balloon. A guide wire is inserted through the inner tube, whereby the guide wire protrudes toward the distal end side of the balloon.

  Here, the shaft of the balloon catheter needs to be flexible enough to bend easily along a bent or meandering blood vessel, and to have a pushing force to push the balloon to the stenosis site. More specifically, a certain degree of rigidity is required near the proximal end, while high flexibility is required at the distal end.

  One way to meet these requirements is to make the shaft material harder on the proximal side and softer toward the distal side. However, since it is not easy to manufacture a shaft made of such a material, conventionally, there is one in which a change in hardness is given to the shaft by providing a core wire along the longitudinal direction of the shaft. In other words, by providing a core wire in the shaft that becomes thinner toward the tip side (distal side), it has a certain degree of rigidity on the proximal side (hand side) and is flexible toward the distal side (tip side). It is possible to realize a shaft with increased performance. The balloon catheter which has a core wire is disclosed by patent document 1 and patent document 2, for example.

  Conventionally, in a balloon catheter, for example, as described in Patent Document 3, a contrast marker made of a radiopaque material is provided at the position of the balloon, and the doctor positions the balloon with the contrast marker. While confirming, the balloon is positioned at the stenosis position.

JP 2006-187315 A JP 2012-020077 A JP 2013-070882 A

  By the way, it is necessary to push the balloon catheter into the tortuous position to the stenosis position, and the resistance when pushing the balloon catheter changes depending on the bending condition of the blood vessel. Therefore, the doctor pushes in the balloon catheter while finely adjusting the pushing force.

  Here, the position of the balloon can be confirmed by a contrast marker provided at the position of the balloon, but it is difficult to confirm the actual state of the shaft. If the degree of bending of the shaft in the blood vessel can be confirmed, the doctor can adjust the pushing force while referring to it, which is considered very convenient.

  The present invention has been made in consideration of the above points, and provides a catheter capable of confirming the state of a shaft in a blood vessel with a simple configuration.

One aspect of the catheter of the present invention is:
A catheter inserted into a blood vessel,
A first contrastable radiopaque material provided at a predetermined position of the catheter;
A cored bar provided in the lumen of the shaft of the catheter over the longitudinal direction of the shaft;
A second radiopaque material that coats the cored bar over the longitudinal direction of the cored bar located away from the first radiopaque material;
It comprises.

  According to the present invention, the state of the shaft in the blood vessel can be confirmed with a simple configuration.

Schematic which shows the whole structure of the balloon catheter which concerns on embodiment Sectional view of the balloon catheter shaft

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a schematic diagram showing the overall configuration of a balloon catheter according to an embodiment of the present invention. The balloon catheter 100 includes a hub 110, a balloon 120, a proxy shaft 130, and a distal shaft 140 as main bodies.

  A guide wire insertion port 150 for inserting the guide wire 160 is formed at the boundary between the proxy shaft 130 and the distal shaft 140. The proxy shaft 130 is mainly composed of an outer tube. The distal shaft 140 is mainly composed of an outer tube and an inner tube. Specifically, the proxy shaft 130 has a single tube structure with an outer tube, and the distal shaft 140 has a double tube structure with an outer tube and an inner tube. These configurations will be described in detail later with reference to FIG.

  The hub 110 is placed at the hand of a doctor who operates the balloon catheter 100 in angioplasty. The hub 110 is configured to be connectable to a pressure application device (not shown) such as an indeflator that supplies and discharges fluid by pressure. The proximal shaft 130 is joined to the hub 110 so as to be in fluid communication, and extends distally. Further, a distal shaft 140 is joined to the distal side so as to be in fluid communication. A balloon 120 is joined to the distal side of the distal shaft 140. The proxy shaft 130 and the distal shaft 140 have a flow path for supplying high-pressure fluid into the balloon 120.

  FIG. 2 shows a cross-sectional view of the shaft portion of the balloon catheter 100 cut in the longitudinal direction. The proxy shaft 130 is configured by joining an outer tube 132 to a metal tube 131. As a material of the outer tube 132, a polyamide-based resin, a urethane-based resin, or a polyethylene-based resin can be used.

  The distal shaft 140 has a double tube structure in which an inner tube 133 is disposed in a tube of the outer tube 132. The inner tube 133 is for inserting the guide wire 160 (FIG. 1). The inner tube 133 extends from the boundary position between the proximal shaft 130 and the distal shaft 140 to a position further to the distal side than the balloon 120 so as to penetrate the inside of the outer tube 132 and the balloon 120. Thereby, the guide wire 160 inserted from the guide wire insertion port 150 passes through the inner tube 133 and protrudes from the guide wire insertion port 151. As a material for the inner tube 133, a polyamide-based resin, a urethane-based resin, or a polyethylene-based resin can be used similarly to the outer tube 132.

  The proximal end of the balloon 120 is joined to the distal end of the outer tube 132, and the distal end of the balloon 120 surrounds the outer circumferential surface of the inner tube 133 and is joined to the outer circumferential surface thereof. As a result, the high-pressure fluid supplied into the outer tube 132 via the hub 110 (FIG. 1) flows into the balloon 120 through the outer tube 132 and stays in the balloon 120. As a result, the balloon 120 120 expands. The balloon 120 is folded to approximately the same size as the outer diameter of the distal shaft 140 before the high-pressure fluid is supplied to the inside. When the high-pressure fluid is supplied to the inside of the balloon 120, the balloon 120 expands by expanding the fold. 1 and 2 show a state where the balloon 120 is expanded.

  A contrast marker 180 made of a radiopaque material is provided on the outer surface of the inner tube 133. The contrast marker 180 is provided at a position corresponding to the balloon 120. The doctor can position the balloon 120 at the stenosis position while confirming the position of the balloon 120 with the contrast marker 180.

  A metal core wire 170 is provided in the outer tube 132. The proximal end of the core wire 170 is joined to the metal tube 131 by welding. The length of the core wire 170 is selected so that the distal end (tip) thereof is positioned in front of the balloon 120 of the distal shaft 140. As can also be seen from the figure, the core wire 170 is disposed in the distal shaft 140 between the inner tube 133 and the outer tube 132, that is, between the outer surface of the inner tube 133 and the inner surface of the outer tube 132. .

  The core wire 170 has a shape that becomes thinner from the proximal end (proximal end) to the distal end (distal end). Thereby, the rigidity in the direction perpendicular to the longitudinal direction of the core wire 170 gradually decreases as it goes from the proximal end (proximal end) to the distal end (distal end). As a result, the balloon catheter 100 can prevent kink and buckling of the catheter without abrupt changes in rigidity at the distal end portion of the metal tube 131 while maintaining the flexibility of the distal end of the catheter.

  In addition to such a configuration, the core wire 170 is coated with a radiopaque material. As the radiopaque material, heavy elements of Hf to Hg heavier than Ba, such as Au, Pt, Ir, and W, are used. The radiopaque material is preferably coated over the entire core wire 170. In this way, the movement of the catheter of the shafts 130 and 140 can be grasped under fluoroscopy. Specifically, it becomes possible to confirm the bending state of the shafts 130 and 140 in the blood vessel and whether or not the shafts 130 and 140 are buckled. Thereby, the doctor can also adjust the pushing force of the shafts 130 and 140 while referring to it. Further, when the shafts 130 and 140 are difficult to enter the blood vessel, it is possible to determine whether the cause is the bending of the blood vessels or the buckling of the shafts 130 and 140. When there is a cause for buckling of the shafts 130 and 140, it is possible to perform measures such as promptly reinserting.

  According to the present embodiment, by coating the core wire 170 with the radiopaque material, the balloon catheter 100 that can confirm the state of the shafts 130 and 140 in the blood vessel can be realized with a simple configuration.

  In the above-described embodiment, the core wire 170 is used as a linear cored bar member disposed between the inner surface of the outer tube 132 and the outer surface of the inner tube 133, and one end of the core wire 170 is welded to the metal tube 131. However, the present invention is not limited to this, and the metal tube 131 itself may be thinned toward the distal side and used instead of the core wire 170. And what is necessary is just to make it apply | coat like this Embodiment to this metal core member.

  In the above-described embodiment, the case where the X-ray opaque material is coated over the entire core wire (core metal member) 170 has been described. However, the present invention is not limited to this, and the core wire (core metal member). A radiopaque material may be disposed along the longitudinal direction of 170. At this time, the radiopaque material may be linear or zigzag. However, considering the visibility to the user, the radiopaque material is preferably arranged with a regular pattern. In consideration of visibility, the most preferable configuration is that the X-ray impermeable material is coated over the entire core wire (core metal member) 170 as in the embodiment.

  In the above-described embodiment, the case where the present invention is applied to a balloon catheter has been described. However, the present invention is not limited to this, and a catheter having a cored bar portion provided in the shaft over the longitudinal direction of the shaft. Widely applicable to. The present invention can be applied to, for example, a catheter used for IVUS (intravascular ultrasound), a catheter used for vascular endoscopy, and the like.

  Furthermore, in the above-described embodiment, the case where the present invention is applied to a double tube structure catheter including an outer tube and an inner tube has been described. It can also be applied to catheters. It can also be applied to a single-tube catheter.

  The above-described embodiments are merely examples of implementation in carrying out the present invention, and the technical scope of the present invention should not be construed as being limited thereto. That is, the present invention can be implemented in various forms without departing from the gist or the main features thereof.

  The present invention can be applied to a balloon catheter having a cored bar member.

100, 200 Balloon catheter 110 Hub 120 Balloon 130 Proximal shaft 131 Metal tube 132 Outer tube 133 Inner tube 140 Distal shaft 150 Guide wire insertion port 160 Guide wire 170 Core wire 180 Contrast marker

Claims (2)

A catheter inserted into a blood vessel,
A first contrastable radiopaque material provided at a predetermined position of the catheter;
A cored bar provided in the lumen of the shaft of the catheter over the longitudinal direction of the shaft;
A second radiopaque material that coats the cored bar over the longitudinal direction of the cored bar located away from the first radiopaque material;
A catheter comprising: The second radiopaque material is not exposed to blood when the shaft is inserted into a blood vessel;
The catheter according to claim 1.

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