JPH07308383A - Catheter - Google Patents

Abstract

PURPOSE:To provide a catheter which comprises a rigid tube and a soft cover structure and has a spiral slit at a part or in the entire length of the rigid tube. CONSTITUTION:A spiral slit 2 is put into a rigid tube 1 so as to allow the changing of a bending elastic modulus of the tube, which enables the varying of the rigidity freely from a very soft structure to the traditional rigid tube 1. This structure facilitates the inserting of a catheter into a celom without damaging the celom and without causing pains to a testee.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a novel catheter. More specifically, the present invention relates to a catheter that can be flexibly adjusted in the axial direction to form a flexible structure and can be easily inserted into a body cavity.

[0002]

2. Description of the Related Art In recent years, medical catheters have come into wide use as medical technology advances. The catheter has a flexible lumen, for example, a catheter for discharging body fluid or blood from the lumen or injecting a therapeutic agent, a bladder catheter for urination, an abdominal cavity, a catheter for puncture of the thorax. , Ventricular drainage catheter, radiopaque intravascular catheter for diagnosis of heart disease and vascular disease, central venous catheter for infusion and venous pressure measurement, etc. With a porous catheter that advances from the peripheral vein to the pulmonary artery by measuring the cardiac output by measuring the intracardiac pressure and the thermodilution method,
A wide variety is used for therapeutic and diagnostic purposes.
In order to insert a catheter into a body cavity, the catheter has the flexibility to bend freely according to the shape of the blood vessel, trachea, etc., and at the same time, it has the so-called pushability so that it can be pushed into the bent body cavity. It is necessary. In addition, torque transmissibility that allows the tip to be freely rotated from the operation unit outside the body is also required. A metal catheter can be used for a region having a relatively small degree of bending. However, it is necessary to use a flexible rubber or plastic catheter for a portion having a large number of bends. At that time, there are many problems that pushability and torque transmissibility cannot be satisfied. In addition, catheter materials have high antithrombogenicity in applications that contact blood, high hydrolysis resistance in applications that contact digestive fluid, and oil content in applications that contact nutrients. A variety of performances are required, such as strength reduction due to absorption and a small permanent elongation. However, there has been no material which has sufficient flexibility and can meet these requirements.

[0003]

Under the circumstances, the present invention provides a catheter which has excellent flexibility, pushability and torque transmissibility, and which has improved the drawbacks of a flexible rubber or plastic material. It was made for the purpose of doing.

[0004]

DISCLOSURE OF THE INVENTION As a result of intensive studies to develop a catheter having the above-mentioned preferable properties, the present inventors have found that a rigid tube having a spiral slit in a certain portion and a soft coating. It has been found that the object can be achieved by combining the structures, and the present invention has been completed based on this finding. That is, the present invention is (1) a catheter comprising a tube made of a rigid material and a soft coating structure, the catheter having a spiral slit over a part or the entire length of the tube made of a rigid material. ,
(2) A catheter characterized in that the pitch width of the spiral slit gradually increases from the tip of a tube made of a rigid material to the operating portion, (3) a catheter having a balloon at the tip, (4) a rigid material Catheter characterized in that the tube is made of super elastic material, (5)
A catheter characterized in that a tube made of a rigid material is made of a shape memory material, and (6) a catheter characterized in that a tube having a slit is provided in a part of the tube made of a rigid material, and (7) rigidity A catheter composed of a material tube and a soft covering structure, having a spiral slit in a part or the entire length of a rigid material tube, and another tube is inserted inside the rigid material tube (8) A catheter comprising a rigid material tube and a soft covering structure, wherein the rigid material tube has a spiral slit over a part or the entire length thereof, and the rigid material tube is different from other tubes. A catheter inserted inside,
(9) A catheter composed of two tubes made of a rigid material having different tube diameters and a soft covering structure, having a spiral slit over a part or the entire length of the tube made of a rigid material, and having different tube diameters. A catheter in which one of two tubes made of a rigid material is inserted into another tube, and (10) a catheter composed of a tube made of a rigid material and a soft coating structure, wherein Alternatively, a catheter having a sliding structure having a spiral slit over the entire length, or the like can be given as an embodiment of the present invention.

The present invention will be described in detail below. The tube made of a rigid material used in the catheter of the present invention is a tube made of a rigid material such as metal or plastic having a high elastic modulus, which is spirally slit over a part or the entire length. FIG. 1 is a perspective view of one embodiment of a tube made of a rigid material which is slit-processed used in the present invention. The slit 2 is processed in a spiral shape from the left end of the tube 1 made of a rigid material to the central part, and the pitch width of the slit 2 becomes coarser from the left end toward the central part. Therefore, the tube made of this rigid material has the smallest bending elastic modulus at the left end, and the bending elastic modulus continuously increases toward the central portion. That is, the left end of the tube made of the rigid material is easily bent by applying a slight force, while the tube made of the rigid material is hard to be bent gradually, and the right end which is not slit is processed. The operation portion has the bending elastic modulus of the tube made of the originally rigid material. On the other hand, considering the compression modulus of the tube made of a rigid material that has undergone the spiral slit processing, if the gap between the slits formed by the slit processing has an appropriate width, the slit processing is included. Since it has almost no effect on the compressive stress, the rigid tube as a whole has the original compressive elastic modulus, and thus maintains good pushability. The bending elastic modulus of the rigid tube used for the catheter of the present invention can be arbitrarily changed by selecting the pitch width of the spiral slit processing. That is, if the pitch width is shortened, the bending elastic modulus of the rigid material tube becomes small, and the rigid material tube has a flexible structure as a whole. If the pitch width is changed according to the axial direction of the rigid material tube,
It is possible to create a tube made of a rigid material that has an elastic modulus change arbitrarily according to the axial direction. Usually, catheters used for medical purposes have a flexible distal end, and it is often preferable that the catheter becomes stiffer as it gets closer to the operating part outside the body.
For such a purpose, processing is selected so that the pitch width of the spiral slit processing gradually increases in the axial direction from the tip of the tube made of a rigid material.

There is no particular limitation on the method of spirally slitting a tube made of a rigid material used in the catheter of the present invention, and any known method can be arbitrarily selected.
For example, it is possible to insert a spiral slit with a grinding tool while attaching a tube made of a rigid material to a rotating shaft of a machine tool and rotating the slit while changing the slit width according to a preset program.
Alternatively, use a laser oscillator instead of the grinding tool,
Slits can be made by laser processing. In the case of laser processing, it is preferable to put a protective core in a tube made of a rigid material because the inner surface on the opposite side of the tube will not be damaged. As the material of the rigid tube used for the catheter of the present invention, metals such as stainless steel can be preferably used, but polyamide, polycarbonate, polyester, polysulfone and the like having a relatively large elastic modulus depending on the purpose. Plastic can also be used. A super elastic body can be used as the material of the rigid tube used for the catheter of the present invention. If a superelastic body with a small elastic modulus and large deformation for small stress and a constant elastic modulus for stress above a certain level is used, it is particularly easy to insert it into a bent tubular part in the body. Therefore, it is preferable.

A shape memory material can be used as the material of the rigid tube used in the catheter of the present invention. A suitable shape memory material is, for example, Ni-Ti.
And the like, shape memory plastics such as norbornene polymer, and the like. The catheter to be inserted into the body has a convenient shape for insertion operation,
The shape suitable for exerting the function in the body after insertion is often different. A rigid tube made of a shape-memory material is shape-memory molded into a shape suitable for exhibiting its function in the body, and if it is cooled and fixed in a shape that is easy to insert into the body, it can be inserted into a prescribed part of the body cavity After that, it can change to the desired shape and exert its function.
In the catheter of the present invention, the tube made of a rigid material is covered with a soft covering structure. The soft covering structural material used here has a sufficiently low elastic modulus and does not affect the bending elastic modulus of the tube made of a rigid material, which is reduced by the spiral slit processing. Examples of such a soft covering structure material include silicone rubber, polyurethane and natural rubber. By covering the tube made of a rigid material with a soft material, it is possible to prevent the liquid or gas from flowing out of the catheter through the slit portion, and at the same time, the liquid or gas flows from the outside of the catheter into the catheter through the slit portion. It can also be prevented. Furthermore, the soft covering structure applied to the surface of the tube made of a rigid material of the catheter prevents the catheter from kinking when the force in the rotational direction is applied to the catheter, and the shape of the catheter is maintained to maintain good torque transmission. be able to. Further, the soft covering structural material used for the catheter of the present invention can be an antithrombotic material, if necessary. As the antithrombogenic material, for example, polyurethane, silicone rubber or the like can be used.

In the catheter of the present invention, the method of covering the tube made of a rigid material with the soft coating structure is not particularly limited, and any known method can be selected. For example, a soft tube having an inner diameter that is slightly larger than or equal to the outer diameter of a tube made of a rigid material can be manufactured, and this soft tube can be covered on a tube made of a rigid material that is spirally slit. . In addition, by immersing a rigid material tube that has undergone spiral slit processing in latex such as natural rubber, and then pulling it up and drying it, it is possible to fabricate a soft covering structure on the inner and outer surfaces of the rigid material tube. it can. Furthermore, the mixture of polyurethane prepolymer and chain extender can be applied on a tube made of a rigid material that has undergone a spiral slit process, or a spiral slit in a mixture of polyurethane prepolymer and chain extender. A soft polyurethane film can be formed on the rigid tube by immersing and lifting the processed rigid tube. In the catheter of the present invention, a balloon can be provided at its tip. Percutaneous transluminal coronary dilatation performed as one of the treatment methods for myocardial infarction,
A guiding catheter and a guide wire are inserted percutaneously into the coronary artery stenosis site and the balloon is guided to expand the stenosis site by the balloon. Also,
As a mechanical assisted circulation method for the left ventricle that has become dysfunctional after acute myocardial infarction, counterpulsation that synchronizes the expansion and contraction of the balloon catheter inserted in the descending aorta with the heartbeat is performed. Insertion of these balloons requires extremely delicate and accurate control of the indwelling site of the balloon, and the use of the catheter having the balloon of the present invention can easily achieve the purpose.

In the catheter of the present invention, a tube made of a rigid material, which is spirally slit to reduce the bending elastic modulus, can be used in combination with another tube. FIG. 2 is a perspective view of a double-tube catheter of one embodiment of the present invention. In this double-tube catheter, a tube 3 made of a rigid material having a spiral slit 2 is inserted with a tube 3 having no other slits through a branch portion 5, and a balloon 4 is provided at the tip thereof. Has been. Although the balloon is shown in an expanded state in FIG. 2, the balloon is deflated and wound around the tube 3 when it is inserted into the body.
FIG. 3 is a perspective view of a double-tube catheter according to another aspect of the present invention. In this aspect, a tube 6 made of a rigid material having a thin diameter and having a spiral slit 2 is inserted into a thick plastic tube 3 through a branch portion 5, and a balloon 4 is attached to the tip portion thereof. .
FIG. 4 is a perspective view of a double-tube catheter according to still another aspect of the present invention. In this embodiment, a tube made of a rigid material having two spiral slits having different diameters is used, and a spiral slit 2 is provided in a tube 1 made of a thick rigid material having a spiral slit 2. A tube 6 made of a rigid material having a small diameter is inserted through the branch portion 5, and a balloon is provided at the tip thereof.

The catheter of the present invention can be used as a sliding catheter. FIG. 5 is a perspective view of a sliding catheter according to another aspect of the present invention. In this embodiment, a tube made of a rigid material having two spiral slits having different diameters is used, and a tube 1 made of a thick rigid material having a spiral slit 2 is provided with an operating portion 7 at the end. Tube 6 made of rigid material with a thin diameter and having a spiral slit 2
Is inserted, and a seal structure 8 is provided at the end of the tube made of a rigid material having a large diameter on the side of the operating portion, so that the tube 6 made of a thin rigid material can freely slide in the tube 1 made of a thick rigid material. It has a structure. Further, a liquid feed port 9 or the like can be provided in the operating portion of the tube 1 made of a rigid material having a large diameter. This sliding catheter is inserted into the body with a thin rigid tube inside a thick rigid tube, and then slides the thin rigid tube after the tip of the insertion tube reaches near the specified site. When extruded, the tip of the thin rigid tube is extremely flexible due to the spiral slit, so that even a slightly bent portion can be reached without resistance and without damaging the tube wall. It is possible to carry out a treatment by sending a drug solution through a tube made of a thin rigid material, or send a contrast agent for examination and diagnosis. Further, by providing a blade, a needle, or a polypectomy ring at the tip of a thin rigid tube, it is possible to perform an incision, puncture or excision of the affected area for simple surgical treatment. Figure 6
FIG. 3 is a perspective view of a sliding catheter having a balloon according to one embodiment of the present invention. As described above, in the sliding catheter, the balloon 4 can be installed in the thick rigid material tube and the thin rigid material tube.

The catheter of the present invention is formed of a rigid tube. The material that makes up the tube is
A tube made of metal or hard plastic that is not slit is hard and has high rigidity, but by bending the tube of a rigid material into a spiral shape, the bending elastic modulus of the tube becomes low, It will bend freely with force. The bending elastic modulus of a tube made of a rigid material can be adjusted as desired. The narrow slit width of the spiral reduces the bending elastic modulus, and the wider slit width increases the bending elastic modulus. If no slit is inserted, the tube made of rigid material retains the original bending elastic modulus of the tube. The tip of the tube made of a rigid material is slit into a narrow width, the width of the slit is gradually widened toward the center, and the tip of the tube is the most flexible and gradually hardened toward the center. . However, the method of processing a tube made of a rigid material is not limited to this. Figure 7
FIG. 3 is a perspective view of a catheter having a balloon according to one embodiment of the present invention. In the catheter of this aspect, there is a slit-less ring portion 10 at a position slightly closer to the center than the distal end portion of the catheter, and a spiral narrow slit 11 is provided between the two ring portions. The rigid tube of the lever has a very flexible structure, and a balloon is provided there. From the ring portion on the central portion side to the central portion, spiral slit processing is performed so that the slit width gradually increases, and the bending elastic modulus of the rigid tube gradually increases. An air supply pipe 13 having a connector 12 is provided at the end portion on the side where the balloon is not provided, and the air is sent through the air supply pipe to inflate the balloon.

[0012]

EFFECTS OF THE INVENTION The catheter of the present invention changes the bending elastic modulus of a tube by forming a spiral slit in the tube made of a rigid material, and can freely change from the extremely flexible structure to the rigidity of the tube of the original rigid material. Since it can be changed, it can be easily inserted into the body cavity without damaging the body cavity or causing pain to the subject.

[Brief description of drawings]

FIG. 1 is a perspective view of an embodiment of a rigid tube made of slit material used in the present invention.

FIG. 2 is a perspective view of a dual-tube catheter of one aspect of the present invention.

FIG. 3 is a perspective view of a double-lumen catheter of one aspect of the present invention.

FIG. 4 is a perspective view of a dual-tube catheter of one aspect of the present invention.

FIG. 5 is a perspective view of a sliding catheter of one aspect of the present invention.

FIG. 6 is a perspective view of a sliding catheter having a balloon according to one embodiment of the present invention.

FIG. 7 is a perspective view of a catheter provided with a balloon according to one embodiment of the present invention.

[Explanation of symbols]

 1 Rigid material tube 2 Slit 3 Tube 4 Balloon 5 Branching part 6 Thin diameter rigid material tube 7 Operating part 8 Sealing structure 9 Liquid supply port 10 Ring part 11 Narrow slit 12 Connector 13 Air pipe

Claims (1)

[Claims] 1. A catheter comprising a tube made of a rigid material and a soft coating structure, the catheter having a spiral slit in a part or the entire length of the tube made of the rigid material.