JP3272608B2 - Medical guidewire - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a medical guidewire used for introducing a catheter into the cardiovascular system.

[0002]

2. Description of the Related Art For the purpose of angiography, a catheter having a very fine flexible tube is inserted into a blood vessel, or when a balloon catheter is inserted into a blood vessel in the treatment of an occluded portion of a coronary artery. In order to ensure the safe insertion of the catheter, a medical guide wire made of a flexible wire is used.
There are a number of known examples disclosed in JP-A-2020453 and JP-A-7-7652. And, they have a common shape of a flexible ultrafine wire that can be inserted into a blood vessel, pass a catheter through a guide wire inserted and set in advance in a blood vessel, and make the guide wire function as a guide line, thereby forming a catheter. The distal end is inserted and set at a predetermined position in a blood vessel, and thereafter, only the guide wire is pulled out to perform a predetermined treatment such as angiography.

That is, (see FIG. 5), since the guide wire 1 is inserted into a blood vessel or a branch blood vessel having a meandering complicated path and pushed into the blood vessel from its distal end, it is flexible and has a vertical load resistance (seat resistance) in the traveling direction. Flexibility) is required, especially for the distal end portion where insertion is to be guided, and high flexibility and high flexibility are indispensable. In addition, the direction of the distal end portion is controlled while rotating the proximal end portion that goes out of the body. Since the operation of insertion into a branch vessel or the like is operated, advanced mechanical properties having both appropriate torsional rigidity and steering properties are required.

[0004] In view of this, Japanese Utility Model Publication No. 4-2045 of the above-mentioned known example is used.
No. 3 and No. 7-7652 are ultra-fine core wires 2
The terminal has a circular cross-sectional shape of a uniform diameter in which only a slight length of one of the terminals is narrowed to form a small-diameter portion 4 and the entire length of the core wire 2 including the small-diameter portion 4 is embedded in the resin coating 3. The configuration using a stranded wire as 2 is characterized in that only one of the strands constituting the stranded wire is projected forward and embedded in the resin coating 3.

[0005]

In the conventional structure in which the core wire 2 is provided with the resin coating 3 on the core wire 2, the tip 5 has high flexibility.
Although it is highly flexible and has an insertion progression in a blood vessel, in order to facilitate insertion of the distal end portion 5 into a blood vessel, the distal end portion 5 is photographed with a fingertip immediately before the insertion and plastically deformed to obtain a “U-shape” It is difficult to perform the pre-shaping process in which the "curved portion 8" is provided, and it is used without stopping without obtaining the intended shape of the curved portion 8, resulting in a problem that the insertion work becomes complicated due to a decrease in insertability and the pain of the patient increases. In addition, there is an inconvenience that even if the user wants the fine distal end portion 5 due to circumstances such as the vascular obstruction state of the patient, it is not possible to respond immediately.

The present invention provides a guidewire that solves the above-mentioned disadvantages of the prior art.

[0007]

A guide wire and a method of forming the same according to the present invention for solving the above-mentioned technical problems are described as follows. In a medical guidewire in which a portion having the small-diameter portion is used as a distal end portion of a guide wire for guiding insertion into a blood vessel, the distal end portion of the guide wire is thinner than a main portion of the guide wire other than the distal end portion of the guide wire. The medical treatment is characterized in that there is a pair of guide wire tips at both ends of the wire body, and the pair of guide wire tips at both ends has a combination of a large diameter portion and a small diameter portion having a small difference in diameter. Guide wire ".

That is, the guide wire according to the present invention is a
Double head type with a thin guide wire tip at the end
And a pair of small diameter tips at both ends
Use a structure that combines a large diameter part and a small diameter part where there is a diameter difference.
Use one of the guide wire tips.
By doing so, the pre-shaping process can be performed twice.
And a tip that is sized for the patient's vascular condition
It is characterized by a structure in which a part can be used alternatively.

The guide wire of the present invention is
Single wire, stranded wire, super elastic alloy wire, shape memory alloy wire, etc.
Arbitrarily selected from various materials
For those using the stranded wire, the wires are fixed to the tip of the small diameter part
The aspect in which the element wire fixing portion is provided is adopted. And both
The guide wire tip at the end has a rectangular cross section
Non-circular cross-sectional shape, uniaxial direction passing through the axis
Make a shape with bending points that make it easy to bend
There is.

[0010]

The guide wire of the present invention described above has a distal end
Flexible and flexible with a smaller diameter than the main part of the guide wire
The stepwise improvement improves the progress of insertion into the blood vessel.
And the tip part exists at both ends,
There are two chances of pre-shape processing,
The shape of the curved portion 8 is more appropriate, and the blood is smoother.
Insertion into the tube is possible, and the pair of guide wires
Since the tip part consists of a large diameter part and a small diameter part with a small diameter difference,
Fast healing by choosing the right size for the patient's vascular condition
Treatment can proceed.

[0011] Further, the above aspect using a stranded wire as the core wire
Is stable in the twisted state even in the small diameter part.
The peeling of the resin coating due to the twist break and the defective wire protrusion
Can be prevented. Then, the tip of the guide wire is
Shaped cross-sections are easier to bend in only one axial direction.
In addition, a certain amount of bending rigidity is provided in directions other than the uniaxial direction.
Since the processability of the pre-shape is improved,
The shape setting of the component 8 is improved, and the insertion resistance in the blood vessel is improved.
Disturbance in the bending direction of the bent part 8 due to resistance can be prevented.
Steering operation such as introduction into a branch vessel becomes easy.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS First, a guide according to a first embodiment of the present invention will be described.
This will be described in detail with reference to FIG. Immediately
In addition, the ultrafine stainless steel single core wire 2 is made of nylon 12 or the like.
Circular cross section of uniform diameter D wrapped in resin coating 3
Having a small diameter portion 4 at a part of the end of the core wire 2.
The portion where the small diameter portion 4 is present is
Ear tip 5 (hereinafter simply referred to as tip 5)
The tip portion 5 is a guide wire other than the tip portion 5.
The guide wire is made smaller in diameter than the diameter D1 of the ear main part 6.
Tip parts 5A and 5B are present at both ends of the main part 6
And a main portion of the guide wire between the tip portions 5A and 5B.
6 constitutes a single guide wire 1.

More specifically, the tip portions 5A and 5B are
Use the guide as a leading part when inserting the ear 1 into a blood vessel.
Advanced with a small diameter form that is even thinner than the dwire main part 6
High flexibility and high flexibility, and a pair of tips
The diameters D2 and D3 of the minute 5A and 5B have relatively small diameter differences.
One is a large diameter tip portion 5A and the other is a small diameter tip portion.
5B, one of the pair of tip portions 5A and 5B.
It is a double-headed type that inserts into the blood vessel by selecting
You. In this embodiment, the guide wire main portion 6
The diameter D1 is approximately 0.87 mm, and the diameter D2 of the tip 5A is
0.85 mm, diameter D3 of tip 5B is 0.70 mm, point
The length L of the end portions 5A and 5B is approximately 180 mm.

The guide wire 1 of the embodiment shown in FIG.
There are actions of serial, hand upon intravascular insertion "dogleg shaped curved portion
8 ", the pre-processed attack change is 2
The shape of the bent part 8 should be more appropriate.
And a tip portion 5 suitable for the patient's vascular condition
Choose the size of 5A or 5B for immediate response
Thus, the insertion of the guide wire 1 into the blood vessel is further facilitated.

Subsequently, referring to FIG. 2, a gas monitor according to another embodiment will be described.
The id wire 1 will be described. That is, with the embodiment of FIG.
Similar tip portions 5A and 5B are connected to both ends of the guide wire main portion 6.
In the embodiment provided in FIG.
The bases of the portions 5A and 5B form a tapered portion 9 to guide water.
The wire 14 is connected as the core wire 2 while being connected to the ear main part 6.
A known stranded wire 13 in which about 3 to 5 strands are twisted is used.
Some of the ends of the stranded wire 13 are reduced in diameter in the twisted form.
The small diameter portion 4 is formed, and the wire 14 at the tip of the small diameter portion 4 is
The wire fixing portions 15 are fixed to each other. In addition, this
The wire fixing portion 15 of the embodiment is made of a gold material or a silver material.
It is formed by brazing.

The guide wire 1 according to the embodiment shown in FIG.
End portion 5 is bent to a small radius of curvature or bent in a blood vessel
Is repeated, the strands of the strands 14 are broken and the resin coating 3 is released.
The possibility of peeling of the resin garment 3 is extremely low.
Prevented, stable performance and quality of the tip part 5, stranded wire configuration
Are more flexible and flexible than single wires of the same shape.
You can enjoy the benefits.

That is, when a stranded wire and a single wire having the same diameter are compared with each other,
Solid wires are generally limited in flexibility and rigidity depending on the material
Of twisted wire is more flexible and flexible than single wire, and twisted
Depending on the configuration, the range of change in flexibility and rigidity is intentionally widened.
Can be determined. Therefore, stranded wire is adopted as the guide wire core wire
Then, the variable selection area of mechanical properties as a guide wire
The territory is larger and can be of "higher quality"
You. Then, blood vessel insertion by improving the flexibility of the guide wire
The improved penetration improves guidewire insertion into blood vessels.
Reduce the application of hydrophilic polymer, etc. applied to the outer periphery to improve
And the stranded core wire is not
Because it exists around the circumference, the adhesion of the resin coating 3 is improved,
There is no risk of resin peeling due to insertion bending of
The performance of dwire is stabilized and improved.

Next, referring to FIG. 3, the guide of the embodiment shown in FIG.
An embodiment of a method for forming the wire 1 will be described. That is,
The core wire 2 having the small diameter portions 4 at both ends is formed.
Are connected in series by the connecting tool 16 to be continuous in a single linear body.
The chain core wire 10 is formed. Then, this chain core wire 10 is
After passing through a molding die 17 of a known resin extrusion molding apparatus.
To apply the resin coating 3 to the chain core wire 10 and to form the same.
The passing speed of the die 17 or the pressing of the resin onto the molding die 17
Embed each small diameter part 4 by adjusting the amount of protrusion
Automatically shaped tip portions 5A and 5B of predetermined shape
The continuous body of the id wire 11 is formed.

Thereafter , the guide wire continuum 11
From the location of the connecting device 16 of
Touch-up processing to embed the small diameter part 4 of
1 in which the entire shape of the core wire 2 is embedded in the resin coating 3.
The guide wire 1 is formed sequentially and continuously. This embodiment
According to the molding method, there is a pair of tip portions 5A and 5B.
Double-headed guide wire 1 is efficient and low cost
Can be molded.

Next, another embodiment of the present invention will be described with reference to FIG.
The guidewire 1 of the embodiment will be described. That is, the one in FIG.
Similarly, one having a pair of tip portions 5A and 5B
The tip portions 5A and 5B are smaller than a circle such as an ellipse or an oval.
With the outer cross-sectional shape, the center line 19 in the long side direction is defined as the neutral plane.
Easy to bend only in the X-axis direction and other than the X-axis direction
Direction bending point with appropriate bending rigidity in the direction of
have. In the embodiment shown in FIG.
・ Precise processing of 5B becomes easier and "
Since the shape quality of the curved part 8 "is stable,
Easy to adjust the direction of the tip portions 5A and 5B in the blood vessel
Become.

The guide wire 1 according to the present invention has
It is not limited to the embodiment, and as illustrated in FIG.
The parts 5A and 5B may be tapered,
The cross-sectional shape of 5A ・ 5B is made to be approximately rectangular, polygonal, etc.
Modified shape with bending point only in one axis direction
Further, the wire fixing portion 15 is formed by other fixing means.
May be formed.

[0022]

As described above, the medical gas of the present invention is used.
The guidewire is a highly flexible and highly flexible guidewire tip.
Enables smooth intravascular insertion with more appropriate shape
Preparing for vascular treatment using a catheter
Improvement and efficiency are promoted.
In the case of a stranded wire consisting of a core wire, peeling of resin coating etc.
To prevent the failure of the cable and enjoy the benefits of the twisted wire configuration.
Further improvement of the id wire performance can be promoted. More effects
There is fruit.

[Brief description of the drawings]

1A and 1B show a medical guidewire according to a first embodiment of the present invention, wherein FIG. 1A is a front view thereof, FIG. 1B is an EE sectional view of FIG. 1A, FIG. (D) is G in (A)
G section view

FIG. 2 is a front view of a medical guidewire according to another embodiment of the present invention.

FIG. 3 is an explanatory view of a method for forming a medical guidewire of the first embodiment.

FIG. 4 shows a medical guidewire according to another embodiment of the present invention, wherein (A) and (B) are cross-sectional views of the distal end portion, and (C).
Is the front view of the tip

FIG. 5 is a partial front view of a conventional medical guidewire.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Medical guide wire 2 Core wire 3 Resin coating 4 Narrow diameter portion 5 ・ 5A ・ 5B Guide wire tip 6 Guide wire main portion 8 Curved bent portion 10 Chain core wire 11 Guide wire continuous body 13 Twisted wire 14 Element wire 15 Wire fixing part 16 Connector 17 Molding die

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-4-164459 (JP, A) JP-A-64-62172 (JP, A) JP-A-2-32850 (JP, U) JP-A-58 136148 (JP, U) Japanese Utility Model Showa 57-54410 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) A61M 25/01

Claims (2)

(57) [Claims] 1. A guide wire tip portion of a guide wire, which is a long ultra-fine wire, and a resin wire is applied to a core wire whose end portion has a slightly small diameter portion, and the portion having the small diameter portion is inserted into a blood vessel. In the medical guide wire to be formed, the guide wire tip portion has a diameter smaller than the guide wire main portion other than the guide wire tip portion, and a pair exists at both ends of the wire,
Furthermore, a medical guidewire characterized in that the distal end portions of the pair of guidewires at both ends are constituted by a combination of a large-diameter portion and a small-diameter portion having a small difference in diameter therebetween. 2. The medical guidewire according to claim 1, wherein the core wire is formed of a stranded wire, and a wire fixing portion is provided at a distal end of the small diameter portion to fix the wires of the stranded wire to each other.