JPH0232899B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a self-guide catheter that functions as both a guide wire and a catheter for use in inspecting or treating the condition of an affected area within a blood vessel. More specifically, the present invention relates to a self-guided catheter that has excellent operability, reduces patient pain, and is capable of ultra-selective treatment of affected areas within blood vessels. Conventionally, catheters used to examine the condition of diseased areas within the blood vessels of the human body and to transport medicinal solutions to the affected areas have been developed by feeding a guide wire into the blood vessel in advance and introducing it into the affected area along the outer wall of the catheter. I was getting used to it. Guidewires used for this purpose are, for example, manufactured by COOK, USA.
This is a coiled metal wire manufactured and sold by UMI, USCI, etc., and consists of stainless steel wire and stainless steel wire coils. On the other hand, the catheter is a synthetic resin tube manufactured and sold, for example, by UMI, ECC, USCI, etc. in the United States, and these are used in combination with the above-mentioned metal guide wire. When actually using the metal guidewire and catheter mentioned above, first insert the guidewire into the blood vessel, and once it reaches the target affected area, insert the catheter with the guidewire as a core and cover it. After the catheter has been introduced and reached the affected area, the guide wire is pulled out, and then treatment fluid is injected from the end of the catheter and introduced into the affected area. In this series of operations, the metal guidewire has an uneven surface unique to coiled wires, which makes it easy for blood clots to adhere to it, and the wire is made of metal and is hard, so it is extremely complicated to feed the guidewire into the affected area within the blood vessel. It requires operating procedures and advanced techniques, takes a long time to operate, and because it is a metal wire, it is easy to damage the vascular intima or get under the vascular intima when advancing the guide wire. Such problems were occurring. When this is actually used, it is extremely difficult to advance the guide wire to the target affected area within the blood vessel, and moreover, it causes great pain and burden to the patient during treatment. On the other hand, when introducing a catheter, the catheter itself is thicker than the guidewire, which puts a greater burden on the patient, and it is also difficult to get the tip of the catheter to reach the point where the guidewire has previously reached. This tendency becomes more pronounced as the blood vessels become more peripheral. Overall, the operation using this method not only requires many steps such as introducing a guidewire, introducing a catheter, withdrawing the guidewire, and injecting a drug solution, but also requires the use of multiple guidewires and catheters with various shapes. Since they are often used in combination, they have the disadvantage that they require a long time to operate and that it is extremely difficult to superselectively reach the target affected blood vessel with the catheter. Therefore, with the combination of a conventional metal guidewire and a catheter, there is a high risk of damaging the intima of peripheral blood vessels, including coronary arteries, and it is not recommended to insert the metal guidewire into the stenotic area or its periphery. Therefore, in cases where coronary artery stenosis occurs due to myocardial infarction, for example, the only option is to treat it by surgical means, such as creating a bypass between the aorta and coronary artery during open-heart surgery. However, these treatments place a heavy burden on patients and require a great deal of cost and time. Therefore, as a result of intensive study to improve the shortcomings of the catheter technology using the above-mentioned flow guide wire, the inventors used a synthetic resin monofilament with a hollow structure as a material, gave it a specific structure, and created a guide wire. By combining the functions of a catheter and a catheter, it is possible to super-selectively insert the catheter into affected areas of peripheral blood vessels that were previously inaccessible, making it possible to obtain a self-guided catheter with excellent operability. We discovered this and arrived at this invention. That is, in this invention, the distal end of a hollow monofilament made of synthetic resin is formed into a spherical section, a flexible section, and a tapered section in order from the end, and the section after the tapered section is configured as an operating section, and the spherical section is provided with a drug solution outlet. In addition, a chemical solution inlet was provided at the rear end of the operating part, and a cavity was formed along the length of the monofilament in the hollow part of the bulb part to communicate the cavity in the flexible part to the chemical solution outlet. A small piece of metal that is opaque to X-rays is built in, and at least the remaining part of the hollow part of the operation part has enough space to communicate the chemical solution injection port with the space in the tapered part. An X-ray opaque metal filament with a cross section is built in, and the rear end of the metal filament is led out from the chemical injection port and fixedly supported by the monofilament, thereby creating a space that communicates with the entire length of the monofilament. The gist of this invention is a self-guided catheter that is characterized by being used as a drug liquid transport path. Next, the structure of the self-guide catheter according to the present invention will be explained by giving examples. FIG. 1a is a vertical sectional view showing the basic structure of the self-guided catheter according to the embodiment, and FIG.
FIG. 2 is a cross-sectional view taken along line A-A. This catheter is made of a synthetic resin monofilament 1 having a hollow part 2 that communicates with the entire length, and its distal end is structured into a spherical part 3, a flexible part 4, and a tapered part 5 in order from the end. 5
The entire subsequent portion is constituted by the operation section 6. A medical solution outlet 7 is opened at the tip of the bulb 3, and the operating section 6
The rear end opening serves as a chemical liquid inlet 8. Although the spherical portion 3 has a cylindrical shape with a spherical tip in this embodiment, it may be a true sphere or a long sphere. The chemical solution outlet 7 may be provided on the side surface of the bulb 3 in some cases. The chemical solution outlet 7 is preferably opened in a tapered shape that widens outward in order to reduce pooling of the solution. As shown in FIG. 2, a small cylindrical piece 9 made of an X-ray opaque metal is housed in the hollow part of the spherical part 3. A void 10 formed within the piece 9, i.e.
An elongated hole having a circular cross section along the length of the monofilament 1 allows a space 11 in the flexible portion 4 to communicate with the chemical solution outlet 7 . The ball portion 3 may have a built-in piece 9 as shown in FIG. That is, this small piece 9 has three walls 12 extending in the radial direction from its center, and a long groove 13 with a triangular cross section along the length direction of the monofilament 1 formed between each wall is formed inside the flexible part 4. The hollow space 11 is formed into a hollow space 10 that communicates with the chemical solution outlet 7. When such a small piece 9 is built-in, a chemical solution outlet 7 can be provided on the side surface of the bulb 3, as shown in FIG. Ball part 3
The shape and structure of the small piece incorporated in the flexible part do not need to be as described above, as long as it can communicate the chemical solution outlet with the space in the flexible part. For example, it may be porous with a large number of communicating holes, or it may be something like a bundle of ultra-thin wires. However, it has a hollow structure parallel to the sphere 3 as illustrated in FIG. 2 and/or a grooved structure parallel to the sphere 3 as illustrated in FIGS. 3 and 4. A small piece is more preferable than a mere small piece, such as a rod-shaped body, which does not satisfy these conditions, in terms of facilitating smooth delivery of the drug solution. A small piece of X-ray opaque metal is
It is necessary to have sufficient X-ray opacity to monitor and confirm from outside the body that the bulb has superselectively reached the affected area of the peripheral blood vessel. Materials such as high quality gold, tungsten, platinum, platinum and stainless steel are preferably used. The flexible portion 4 is a hollow, extremely thin and flexible portion, and has sufficient strength. The diameter of the tapered part 5 increases as it goes toward the operating part 6, and is tapered so that it has the same diameter as the operating part 6 when it reaches the operating part 6. Preferably, a part of the hollow part thereof is tapered. It has a built-in metal strip that is opaque to X-rays. The operating part 6 has the same basic structure as the hollow monofilament 1, and has an X-ray opaque metal filament 1 in the hollow part 2 over almost its entire length.
4 is built-in, but the diameter of this metal wire 14 is smaller than the hollow diameter (inner diameter) of the hollow part 2,
In particular, it is preferable to have a diameter of 20 to 80% of the hollow diameter. Since the metal filament 14 has a cross section with a diameter smaller than the hollow diameter of the operating section 6, the opening 16 necessary for communicating the chemical solution inlet 8 with the opening 15 in the tapered section 5 is formed in the operating section 6. It is secured internally.
As the filament having a structure to ensure such a void space, a hollow filament, a porous filament having communicating holes, a bundle of ultrafine wires, etc. may be employed as appropriate. Note that the X-ray opaque metal filaments used here are metal filaments such as stainless steel and tungsten that have excellent contrasting power when irradiated with X-ray rays. In consideration of this, it is usually preferable to use a coating with a resin such as polyethylene, polyethylene terephthalate, or fluororesin.
In addition, the tip direction of the X-ray opaque metal filament is
It is preferable that the catheter be tapered into a sharp point as shown in FIG. 1, which further improves the operability of the catheter and the ability to supply the drug solution. The metal filament 14 is preferably fixed in the following manner, for example. That is, the rear end of the metal filament 14 is bent outward at the rear end opening of the operating section 6,
As shown in Fig. 1, it is fixed by covering it with a tube 17 or the like. If the metal filament 14 is incompletely fixed, the metal filament 14 will shift toward the distal end during injection of the chemical solution, which is undesirable because the introduction of the chemical solution will be interrupted. Note that the drug solution inlet 8 is usually covered with a cap, and as shown in FIG. 1, a connector 18 is further provided so that it can be connected to a syringe or the like. In this way, in the catheter, from the liquid medicine inlet 8 to the liquid medicine outlet 7, the space 16 in the operating part 6, the space 15 in the tapered part 5, the space 11 in the flexible part 4, and the bulb. The cavity 10 in the portion 3 creates a cavity that communicates over the entire length of the monofilament, and this communication cavity becomes the drug liquid transport path of this self-guiding catheter. The drug solution transport path is usually sterilized. The dimensions of each part of the catheter are not particularly limited as they depend on conditions such as the age, constitution, or condition of the affected area of the patient being treated, but typical typical dimensions of each part are as follows.

[Table] Note that the diameter of the tapered portion is not shown as a specific value because it gradually becomes thicker from the flexible portion to the operating portion. Further, although the lengths of the flexible portion and the tapered portion may not always be clearly distinguishable, it is appropriate that the total length of the flexible portion and the tapered portion be within 200 mm. The larger the inner diameter of the hollow portion of the monofilament, the better. The synthetic resin material constituting the self-guided catheter of the present invention is not particularly limited as long as it can be melt-extruded, but polyamide, polyester, polyolefin, fluororesin, etc. can be preferably used. In order to manufacture the self-guided catheter of the present invention, first, a hollow monofilament is spun using a hollow spinneret by a normal melt spinning method, and if desired, this is appropriately stretched to obtain an appropriate length. Cut into. Next, the tip of the cut hollow monofilament is subjected to local high-magnification stretching, leaving the part where the spherical part 3 will be formed, to create the flexible part 4 and the tapered part 5 all at once, and then forming the spherical part. Small pieces 9 and 12 of X-ray opaque metal are inserted into the hollow part of the part, and the spherical part 3 is formed by semi-melt sealing so as to leave the chemical solution outlet 7. Thereafter, an X-ray opaque metal filament 14 is inserted into the hollow portion 2 from the rear end of the operating portion 6 toward the tapered portion 5, and the rear end is bent and fixed near the drug solution inlet 8. Note that at this time, it is preferable to process the end portion of the X-ray opaque metal filament in the forward direction in advance into a tapered shape, thereby further imparting flexibility and elasticity to further improve operability. In addition, when the bulb is completely melt-sealed, the chemical solution outlet 7 can be formed by drilling a small hole from the outside of the bulb 3 to the hollow portion with a very fine drill or the like. Subsequently, a connection terminal 18 such as a cap or a connector is formed or attached to the chemical solution inlet 8 as required. This completes the self-guided catheter of the present invention. It is further preferable to apply an antithrombotic treatment such as silicone coating or Teflon coating to the outer surface of the catheter, thereby further improving antithrombotic properties and operability as typified by slippage. When using the self-guided catheter of the present invention having the above configuration, insert it into a blood vessel and monitor the contrast by X-ray projection.
The tip is made to reach the targeted peripheral blood vessel affected area in a superselective manner, and then the drug solution is introduced into the affected area. This self-guided catheter exhibits the following effects when used. In other words, the most advanced bulb 3 can move freely along the blood vessel within the blood vessel without damaging the intima or penetrating under the intima, making it difficult to push with a conventional metal guide wire. Compared to manual insertion, the device can be introduced into the blood vessel with free movement along the blood vessel, and can be delivered to the target affected area without damaging the vascular intima with a natural and effortless operation. In addition, since the bulb 3 has a built-in small piece 9 of metal that is opaque to X-rays, its position can be easily confirmed when working while projecting X-rays and monitoring with an X-ray television monitor. ,
It is possible to inject the medicinal solution only to the targeted affected area. Since the flexible portion 4 is designed to be thin and flexible, the free movement of the bulbous portion 3 within the blood vessel is made more effective. Since the tapered part 5 is processed into a tapered shape, it is possible to prevent abnormal accumulation of blood, and it also facilitates delicate operations such as advancing and retreating in the process of introducing the bulb part 3 to the entrance of the target blood vessel. I can make you do it. The spherical part 3, flexible part 4 and tapered part 5 of such structure
The tip is flexible and elastic enough to not pierce even tofu, for example.
Destruction of the vascular intima and pain to the patient can be significantly reduced. In addition, since the operating portion 6 is formed from a synthetic resin monofilament, the surface is smooth and highly elastic, making it easy to operate. Furthermore, since the X-ray opaque metal line 14 is built-in over the entire length, the image displayed through the monitor becomes extremely clear. Thus, the self-guided catheter of the present invention can be introduced into the blood vessel with free movement while fully following the complicated running and delicate operations of the blood vessel, and can be easily introduced into meandering parts of the blood vessel or super-selective peripheral blood vessels. can be inserted into. After the tip of the catheter reaches the target affected area, the medicinal solution is injected and pumped from the medicinal solution inlet 8, and the medicinal solution passes through the medicinal solution transport path consisting of the communicating cavity from the medicinal solution outlet 7 to the affected area. It is effectively supplied and provides excellent therapeutic effects. According to this catheter, the medicinal solution is selectively introduced only to the affected area, so treatment can be achieved with a small amount of the medicinal solution and there is no risk of side effects. for example,
Anticancer drugs often have side effects on normal areas, and not only is it impossible to administer a large amount at once, but they are also administered from a site far from the affected area, so conventional catheters do not allow for dilution. Its efficacy is not sufficiently widespread, and the therapeutic effect is inevitably reduced.
On the other hand, according to the catheter of the present invention, the medicinal solution can be administered directly to the affected area, so the amount administered can be kept to the minimum necessary and a great therapeutic effect can be obtained, and there is no fear of side effects. Furthermore, the self-guided catheter of this invention has
It can be applied to super-selective imaging of the coronary arteries of the heart, and can be expected to be used as a so-called coronary catheter. As explained above, since the self-guide catheter of the present invention functions as both a guide wire and a catheter, it is possible to save labor in treatment instruments and significantly shorten treatment time. In addition, since the device itself is thin and has a waist, its dryness is greatly improved, and it becomes possible to insert it into a super-selective intravascular disease site that was previously inaccessible. Moreover, since it is made of a synthetic resin monofilament, it has a smooth surface and antithrombotic properties, and can be processed into various shapes to match the shape of blood vessels. Furthermore, the self-guiding catheter according to the present invention is not only thinner than ordinary catheters for intra-arterial indwelling, but also has an appropriate stiffness due to its built-in metal wire, so it does not interfere with blood flow. When the device is placed in a blood vessel, its position is well maintained and it is prevented from falling out of the target blood vessel. That is, it also has characteristics that allow it to be used as an indwelling catheter for continuous intra-arterial drug infusion. The present invention will be explained in more detail with reference to specific examples below. Example: Using polyethylene terephthalate (type 900) manufactured by Toray Industries, Inc. as a material, using a hollow die, a diameter of 1.0 mm and a hollow hole diameter of
An undrawn hollow monofilament having a hollow portion of 0.7 mm was spun and cut into a length of 1.3 m.
Approximately 3 spherical portions are formed at one end of this monofilament.
A flexible part with a diameter of 0.4 mm and a length of 20 mm and a tapered part with a length of 110 mm were created at once by stretching approximately 3 times using a local stretching device, leaving 0.4 mm in length. Next, from the tip, the outer diameter is 0.65 mm, the hollow diameter is 0.4 mm, and the length is 2 mm.
A hollow metal tip was inserted and heated and semi-sealed to create a bulbous end portion with a chemical outlet. On the other hand, from the rear end of the operating part to the hollow part, the tip diameter is 0.15 mm, and the rear end diameter is 0.15 mm.
Insert a stainless steel #304 metal wire with a tapered tip and a length of 0.255mm and 1.3m, and extend the end of the metal wire protruding from the rear end along the outer wall of the operation unit for about 20 minutes.
Bent by mm. Next, attach an outer diameter of 1.2 mm to the rear end of the operating section.
Glue a polyvinyl chloride tube with an inner diameter of 1.0 mm and a length of 10 mm to an acrylic PET VH type Lulock connector (acrylic hard lock manufactured by Sankyo Co., Ltd.).
E510K) and fixed the end of the metal wire. Through the above operations, a self-guided catheter having the configuration shown in FIG. 1 was obtained. Clinical Example 1 The self-guided catheter prepared in Example was percutaneously inserted into the femoral artery, and the tip of the catheter was advanced into the coronary artery via the aorta, and subjected to a clinical test. While confirming the position of the bulb under the supervision of an X-ray monitor and television, advance the bulb to the periphery of the coronary artery and apply pressure with a precision drug metering pump connected to the drug injection port at the rear end to selectively apply the drug to the affected area. were able to supply. This self-guided catheter consists of a blunt bulb part and an extremely flexible part, and since it itself has the function of a super-selective guidewire, it can be easily inserted to the target affected area.
Furthermore, it was extremely safe to insert into the coronary artery, which is an important blood vessel that nourishes the heart itself, and did not cause arrhythmia or damage the inner wall of the blood vessel. Therefore, it is clear that this self-guided catheter can be applied to selective intracoronary administration, especially continuous administration, of drugs for coronary artery stenosis or occlusive disease. Furthermore, since this self-guided catheter was clearly imaged on a monitor/TV using X-ray projection, a series of operations could be performed reliably and safely. In addition, it was easy to remove the catheter after treatment. Clinical Example 2 The self-guided catheter prepared in Example was superselectively inserted into the hepatic artery of a patient with hepatocellular carcinoma, and continuous arterial infusion was performed. In other words, after inserting a self-guided catheter to the periphery of the target hepatic artery, which has been identified in advance by superselective angiography, anticancer drugs are administered using a continuous infusion pump (Klonoff user) connected to the drug inlet at the rear end. The mitomycin solution was infused at a rate of 1 ml per hour for one week.
This catheter has a blunt tip and an extremely flexible portion, and since it itself has the function of a superselective guide wire, it was easy to insert it superselectively to the periphery of the hepatic artery.

[Brief explanation of drawings]

FIG. 1a is a vertical cross-sectional view showing the basic structure of the self-guided catheter of the present invention, and FIG.
FIG. 2 is a cross-sectional view taken along line A-A. FIG. 2 is an enlarged perspective view of the spherical portion shown in FIG. 1 and its vicinity, and FIGS. 3 and 4 are enlarged perspective views showing other embodiments of the spherical portion. 1... Main body (hollow monofilament), 2...
Hollow part, 3... Ball part, 4... Flexible part,
5...Tapered part, 6...Operation part, 7...Medical solution outlet, 8...Medical solution inlet, 9...Small piece, 10...Vacancy, 11...Vacancy in flexible part, 14...
Metal wire, 15... Blank space in tapered part, 16...
Empty space inside the control section.

Claims (1)

[Claims] 1 The distal end of the synthetic resin hollow monofilament is formed into a ball part 3, a flexible part 4, and a tapered part 5 in order from the end, and the part after the tapered part 5 is formed into an operating part 6, and a chemical liquid is introduced into the ball part 3. Exit 7
In addition, a chemical solution inlet 8 is provided at the rear end of the operating part 6, and a cavity 10 in the hollow part of the bulb part 3 that connects the cavity 11 in the flexible part 4 to the chemical solution outlet 7 is made of monofilament. A small piece 9 of X-ray opaque metal formed along the length is built in, and a drug solution inlet 8 is provided in at least the hollow part of the operating part 6 in the remaining part of the tapered part 4.
A metal filament 14 that is opaque to X-ray radiation is built in and has a cross section sufficient to ensure a cavity 16 necessary for communicating with the cavity 15 inside.
Holes 10, 11, 15, whose rear ends are led out from the drug solution inlet 8 and fixedly supported by the monofilament, communicate with each other over the entire length of the monofilament.
A self-guide catheter characterized in that 16 is a drug liquid transport path.