JPH0156786B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a flow guide wire made of synthetic resin that is inserted into a blood vessel for intravascular catheterization or treatment, and in particular, its main purpose is to improve its antithrombotic properties and operability as represented by slippage. It is something to do. Catheters used to examine the condition of diseased areas within blood vessels of the human body and to transport medicinal fluids to the affected areas are made by first feeding a guidewire into the blood vessel and introducing it along the outer wall of the catheter to the affected area. The guide wires used for this purpose are coiled metal wires manufactured and sold by COOK, UMI, USCI, etc. in the United States, and these are made of stainless steel wire and stainless steel coils. . This guidewire has irregularities unique to coiled wires on its surface, which makes it easy for blood clots to adhere to it, and the metal wire is hard, so when sending the guidewire to the affected area in the blood vessel, you have to push, pull, or turn it to the left or right. It requires extremely complicated operating procedures and advanced techniques, and has drawbacks such as a long operation time, and because it is a metal wire, it can easily pass through the intima of blood vessels. Therefore, when using such a metal wire guide wire, it is extremely difficult to make the guide wire reach the target affected area within the blood vessel.
Moreover, the pain and burden caused to patients during treatment was great. The present inventors have improved the above-mentioned drawbacks of the conventional guidewire, and provided a safe medical flow guidewire that has a smooth surface, is flexible and elastic, is easy to operate, and does not cause pain to the patient. As a result of our research, we found that a linear body made by filling the hollow part of a synthetic resin hollow monofilament with an X-ray opaque material and giving it a specific shape can achieve the above purpose. Proposed. However, during use of this flow guide wire, blood clots adhere to the surface, resulting in decreased blood flow.
Sometimes there is a problem of stopping blood flow, and this tendency is particularly noticeable in peripheral blood vessels. The present inventors continued to study to improve the blood clot adhesion of the above-mentioned flow guide wire, and found that by using a specific resin composition as the constituent material of the hollow monofilament, the anti-thrombotic property was significantly improved. The present invention was achieved by discovering that the operability, typified by slippage, is synergistically improved. That is, the present invention provides a spherical portion from the tip to the rear end of a hollow monofilament obtained from a composition containing 1 to 30% by weight of fluororesin to at least one resin selected from thermoplastic polyester, polyamide, and polyolefin. , flexible part,
The present invention provides an antithrombotic medical flow guidewire comprising a tapered part and a proximal part, and having an X-ray radiopaque substance encapsulated in at least the hollow part of the bulbous part and the proximal part. First, the structure of the synthetic resin medical flow guide wire of the present invention will be explained. FIG. 1 is a side view A and a sectional view B showing a synthetic resin medical flow guide wire of the present invention.
The distal end of the flow guide wire consists of a spherical part 1, a flexible part 2, and a tapered part 3, and a proximal part 4 follows the tapered part. It has a hollow structure over the entire length from the distal end to the proximal part, and an X-ray opaque material 5 is sealed in at least the hollow parts of the distal end 1 and the proximal part 4. To further explain the details of the constituent parts, the bulb 1 located at the tip has a hollow structure.
The hollow part contains an X-ray opaque material 5. Note that the spherical portion 1 is not necessarily limited to a geometrical spherical shape, and can be in the shape of an elongated sphere or a cylinder with a spherical tip. The flexible portion 2 is a hollow or solid, extremely thin and soft portion, and must have sufficient strength so that the bulbous portion 1 and the tapered portion 3 will not be separated within the blood vessel. The diameter of the tapered part 3 adjacent to the flexible part 2 and the proximal part 4 is gradually increased from the flexible part 2,
When it reaches the handle part 4, it is designed and processed into a tapered shape so that it has the same thickness as the handle part 4.
Preferably, the hollow portion contains an X-ray opaque material. The hand portion 4 is basically a hollow monofilament structure, and the hollow portion contains an X-ray opaque material. Regarding the dimensions of each part, the age of the patient to be treated,
It depends on conditions such as the constitution or the condition of the affected area, and although there are no particular limitations, typical typical dimensions are shown in the table below.
Note that it is preferable that the inner diameter of the hollow portion in which the X-ray opaque substance is enclosed be as large as possible.

[Table] The synthetic resin materials constituting the medical flow guide wire of the present invention are polyethylene terephthalate,
Thermoplastic polyesters such as polybutylene terephthalate, nylon 6, nylon 66, nylon
610, nylon 11, nylon 12, nylon 6/66
It is mainly composed of at least one kind selected from polyamides such as polyamides and polyolefins such as polyethylene and polypropylene; The composition contains 1 to 30% by weight, preferably 3 to 15% by weight of base resin. By incorporating 1 to 30% by weight of fluororesin, the antithrombotic properties are significantly improved and the adhesion of blood clots to the flow guide wire surface is significantly reduced, but even more surprisingly, the friction coefficient of the flow guide wire surface is significantly reduced. Perhaps because of this reduction, the slippage against blood vessels and catheters is improved, resulting in a synergistic effect of much improved operability.
However, if the amount of fluororesin is less than 1% by weight, the antithrombotic properties and operability will not improve, and if it is more than 30% by weight, the flexibility and spinning properties of the monofilament will decrease.
This is not preferable because it is economically disadvantageous. In addition, X-ray radiopaque substances include metal filaments such as tungsten, "Conray" (trade name) manufactured by Daiichi Pharmaceutical Co., Ltd., and Schering AG.
Examples include liquids such as Urografin manufactured by Manufacturer Co., Ltd., or a combination of these metals and liquids, but it is preferable to use metals such as tungsten because they have excellent contrasting power when irradiated with X-ray rays. In order to manufacture the medical flow guide wire of the present invention, first, a hollow monofilament made of the above composition is spun using a hollow spinneret by a normal melt spinning method, and if desired, this is stretched as appropriate. Cut to desired length. Next, the tip of the monofilament is locally stretched at a high magnification, leaving the ball-forming part at the tip, to create a flexible part and a tapered part all at once, and then an X-ray opaque material is inserted into the ball-forming part. and melt-seal to form a sphere. Next, an X-ray opaque material is inserted into the hollow part from the other end of the proximal part, and the end of the proximal part is melt-sealed. In addition, when using a metal filament such as tungsten as the X-ray opaque material, it is preferable to process the distal end of the filament into a tapered shape in advance, which gives flexibility to the flow guide wire. Provides flexibility and elasticity, further improving operability. The medical flow guide wire of the present invention having the above-mentioned configuration is inserted into a blood vessel, selectively reaches the target affected area using contrast produced by X-ray projection, and then a catheter is inserted along this. It is used as a so-called catheter aid for inspecting the condition of an affected area in a blood vessel or for transporting a therapeutic drug solution to the affected area.When used, it exhibits the following effects. First, the bulbous portion 1 at the tip can move freely within the blood vessel and does not penetrate into the intima of the blood vessel. Therefore, compared to the conventional ``pushing'' operation of a metal guidewire, the guidewire is introduced into the affected area by free movement along the blood flow, so it is a natural operation that is easy and does not damage the vascular intima. Since the flexible part 2 is designed to be thin and flexible,
Free movement of the bulb 1 within the blood vessel is made more effective. Since the tapered portion 3 is processed into a tapered shape, it is possible to prevent abnormal accumulation of blood, and
The operation can be performed smoothly, and the process of introducing the bulb 1 into the entrance of the target blood vessel allows delicate operations such as forward and backward movements, which require extremely advanced techniques, to be performed almost at will. becomes. The distal end portion of this structure, consisting of the bulbous portion 1, flexible portion 2, and tapered portion 3, has flexibility and elasticity to the extent that it will not pierce silken tofu, for example, so it will not destroy the vascular intima or cause pain to the patient. can be significantly reduced. In addition, the hand portion 4 uses anti-thrombotic synthetic resin monofilament, so the surface is smooth and blood clots will not adhere to it, and it also has a built-in X-ray opaque material along its entire length, making it highly elastic and easy to operate and monitor. The image projected through the lens is also extremely clear. Thus, the antithrombotic medical flow guide wire of the present invention can be introduced into a blood vessel with free movement, fully following delicate manipulations, and can be easily inserted, for example, into meandering portions of blood vessels or super-selective peripheral blood vessels. is possible, and the catheter has good guideability. As explained above, the medical flow guide wire of the present invention has extremely excellent antithrombotic properties and operability, does not cause pain to the patient, and has excellent imaging effects when exposed to X-rays. It is extremely useful for clinical tests and treatments using The present invention will be further explained below with reference to Examples. Example 5 fluororesin powder “TLP-10” manufactured by Mitsui Fluorochemical Co., Ltd. was added to polyethylene terephthalate.
Diameter spun from wt% melt blended composition
A hollow monofilament of 0.8 mm and a hollow pore diameter of 0.33 mm was cut into a length of 1.3 m. Leaving a sphere-forming part at one end of this hollow monofilament, the subsequent part was selectively stretched approximately three times in water vapor to a diameter of 0.3 mm and a length of 50 mm.
A flexible part and a tapered part with a length of 30 mm were created in one step. Next, from the tip of the sphere creation side, diameter 0.3 mm, length 1.5
A rectangular sphere with a diameter of 0.8 mm and a length of 2.5 mm was created by inserting a tungsten piece of mm in diameter and melt-sealing the tip. On the other hand, a tungsten filament with a diameter of 0.25 mm and a length of 1.25 m, tapered at only one end, was inserted with the tapered side first, filling part of the tapered part and the hollow part of the hand. After that, the end of the proximal part was melt-sealed to complete the flow guide wire. This flow guide wire is designated as (A). Further, a flow guide wire obtained by spinning a hollow monofilament of the same size as above from polyethylene terephthalate alone and performing the same processing as above is designated as (B). Using each of the flow guide wires (A) and (B) above, we evaluated the antithrombotic properties and operability when the catheter was advanced from the aorta to the left arterial artery in a clinical test. When used, the flow guide wire can be easily manipulated to reach the target affected area, and the catheter can be selectively introduced along it with excellent slippage, and the surface of the flow guide wire pulled out from the blood vessel It could be cleaned by simply wiping it lightly, and there was no adhesion of coagulum. On the other hand, when (B) is used, the flow guide wire bends when inserted into a bend in the blood vessel, resulting in poor operability and poor slippage when guiding the catheter. Even after wiping it off, there was still some coagulum attached.

[Brief explanation of drawings]

FIG. 1 shows a side view A and a sectional view B of a medical flow guide wire of the present invention. 1... Ball part, 2... Flexible part, 3... Tapered part, 4... Hand part, 5... X-ray opaque material.

Claims (1)

[Claims] 1 A spherical part and a flexible part from the tip to the rear end of a hollow monofilament obtained from a composition containing 1 to 30% by weight of a fluororesin to at least one resin selected from thermoplastic polyester, polyamide, and polyolefin. An antithrombotic medical flow guide wire comprising a tapered part and a proximal part, and having an X-ray opaque substance encapsulated in at least the hollow part of the bulb part and the proximal part.