JPH02289240A - Device for ensuring bore of tubular organ lumen and organ lumen holding catheter incorporating the same device - Google Patents

Abstract

PURPOSE:To recover a device from a residing position and to vary a residing position by providing a linear wire and a cylindrical organ lumen holding part mounted to the tip of the wire and expandable and shrinkable in a radial direction. CONSTITUTION:A title device comprises a linear wire 10, e.g. stainless, piano wire, being difficult to have the habit of bending and having excellent operability and a coilform cylindrical organ lumen holding part 11 extended in the extension direction of the wire 10. The organ lumen holding part 11 serves to ensure the bore of a tubular organ lumen, and is formed by stainless, a piano wire, a shape memory alloy, platinum, or an alloy containing platinum, and is expandable and shrinkable through a temperature change in a radial direction, elasticity or by means of an external force. For example, when the organ lumen holding part 11 is formed by a two-directional shape memory alloy, it is reversibly deformable from a contraction state 11a-1 to an expansion state 11a-2.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an inner diameter securing instrument used to maintain the inner diameter of a tubular organ such as a blood vessel, digestive tract, or trachea to a desired size. The present invention relates to a lumen-maintaining catheter having a built-in lumen-maintaining catheter.

(Prior Art) Conventionally, for example, after dilating a narrowed portion of a coronary artery with a vasodilator catheter, an inner diameter securing device J4. (stent) has been proposed.

Conventionally, as an instrument for securing the inner diameter, a cylinder made of mesh-like stainless steel wire (for example, literature, Surge
ryq 1986, Vol. 99, No. 2, pp. 199-205; or Radiology, 1988, 167:70
7 to 712)% or a cylinder made of a unidirectional shape memory alloy (Japanese Patent Publication No. 61-6655) is known.

When securing the diameter of a blood vessel using the former mesh-like stent, for example, the stent is introduced into a predetermined position in the blood vessel via a vasodilator catheter, and then the i4 rune provided at the distal end of the catheter is expanded to complete the stent. can expand to the diameter of the blood vessel.

In the case of the latter unidirectional shape memory alloy stent, the stent can be similarly introduced into a predetermined position in a blood vessel and then heated with hot water or the like to restore and expand the stent to its memorized shape.

(Problem to be Solved by the Invention) However, in the case of the former mesh-like stent, whether it is a Crohn's expansion type or a self-expanding type, once it is placed in a blood vessel, it must be taken out again even if the affected area recovers. I can't. Therefore, the biocompatibility of stents becomes a major issue. Furthermore, even if it is discovered that such conventional stents are placed in the wrong position or after placement,
- Once the device is installed, it cannot be changed. In addition, if the tube is left permanently in place in this way, if restenosis occurs due to intimal hyperplasia after blood vessel dilatation, it is impossible to dilate the stenosis again by balloon dilatation.

This also applies to stents using unidirectional shape memory alloys. That is, once it is restored to its memorized shape and expanded, it cannot change its shape unless an external force is applied, and it remains indwelled in the affected area.

The greatest need for stents after vasodilation is
This is when the blood vessel wall ruptures or dissociates due to dilation, resulting in a flap-like occlusion. For this purpose, fixing the flap to the vessel wall for a day or two is sufficient, and permanent stent placement is not necessary.

Therefore, even if the present invention is expanded and placed in a tubular organ once, it can be freely contracted again. Therefore, it is possible to recover from the placement position and also to change the placement position after expansion. It is an object of the present invention to provide an instrument for securing the inner diameter of a tubular organ which can be freely made. Furthermore, it is an object of the present invention to provide a lumen-maintaining catheter that is slidable and has a built-in device for securing the inner diameter in order to operate the device.

(Means for solving the problem) That is, the present invention provides a tubular organ lumen comprising a straight wire and a cylindrical lumen holding part attached to the tip of the wire and expandable and contractible in the radial direction. A device for securing the inner diameter of the pipe is provided.

Furthermore, the present invention is characterized in that it comprises a catheter main body and the above-mentioned inner diameter securing device, and the lumen holding portion of the inner diameter securing device is inserted into and removably inserted into the inside of the catheter main body. The present invention provides a lumen-maintaining catheter.

The material of the straight wire is stainless steel, superelastic alloy, piano wire, etc., which have a tendency to bend.Although it is preferable to use a material with good operability, it is not necessarily limited to the above examples. Preferred examples of materials include stainless steel,
Examples include superelastic alloys, piano wires, shape memory alloys, tungsten alloys, platinum or alloys containing platinum, and silver/#radium alloys. The form of the cylindrical lumen holding part is not particularly limited as long as it is substantially cylindrical. Substantive here! 1C@ shape refers to one that has an outer surface that is capable of expanding the inner lumen of a tubular organ during expansion and maintaining the expanded state. For example, a coil-shaped one, a cylindrical one with slots and grooves in the longitudinal direction, a square-shaped one, and a square-shaped one can be selected as appropriate. Furthermore, the cylindrical body may be made so that at least a portion thereof is opaque to Xfa so that it can be operated under X-ray fluoroscopy.

The straight wire and the cylindrical lumen holding portion may be coated with a resin or treated to resist erecting so that they can slide easily and resist erecting.

The catheter body may be any flexible catheter as long as it has an inner diameter that allows the catheter to be inserted into the lumen of the tubular organ to be introduced, and an inner diameter that allows the lumen holding part in the contracted state to be accommodated therein.

(Function) According to the present invention, when securing the inner diameter of the inner lumen of a tubular organ,
With the lumen holding part stored in the catheter body in a contracted state, the tip of the catheter body is introduced into a desired position in the lumen of the tubular organ, and then the straight wire is pushed out in the distal direction,
By this, the lumen holding part is led out from the tip of the catheter main body, and the lumen holding part is expanded into an enlarged cylindrical shape using its elasticity, heat-sensitive properties, etc., and is indwelled at that site to lumen the tubular organ. Ensure that the inner diameter of After that, if you want to retrieve or change the position of this indwelling lumen holding part, use its elasticity and heat-sensitive properties to manipulate the straight wire to store it inside the tip of the catheter body again, and move the catheter body in this state. That's fine.

(Example) Hereinafter, the present invention will be explained with reference to illustrated embodiments.

FIG. 1 (4) is a plan view showing a general view of the device for securing the inner diameter of the inner lumen of a tubular organ according to the present invention. It consists of a linear wire O made of a material with good operability and a coiled cylindrical lumen holding part 1 attached to the tip of the wire 10 and extending in the direction of extension of the wire 10. This lumen holding part 11 is for securing the inner diameter of the inner lumen of the tubular organ, and is, for example, made of stainless steel, piano wire, superelastic alloy, shape memory alloy (unidirectional shape memory alloy or heated,
Bidirectional shape memory alloys that memorize their respective shapes upon cooling), tungsten alloys, platinum or platinum-containing alloys, and silver-noradium alloys that change temperature in the radial direction.
It can be expanded or contracted by elasticity or external force.

For example, if the lumen holding part 1 is made of a bidirectional shape memory alloy, it can be reversibly deformed from the contracted state shown in the first national meeting to the enlarged state shown in Figure 1 (03) due to temperature changes. There is.

The wire 10 and the lumen holding part 11 may be integrally formed using the same material, or may be welded, brazed, or
It may be connected by caulking or the like.

The wires 10 may have the same wire diameter, but the cylindrical body 11
In order to make it easier to operate, a tip with a gradually tapered tip may be used.

The wire 10 and the lumen holding part 1 are coated with Teflon or silicone to improve lubricity, immobilized with heparin, urokinase, etc. to provide anti-slip properties, polyethylene oxide, I-lipinyl, etc. Hydrophilicity may be imparted by grafting a hydrophilic polymer such as pyrrolidone or methyl vinyl ether-maleic acid monoethyl ether copolymer.

The shape of the lumen holding part 11 is not limited to the above example, but may be substantially cylindrical. Here, the term "substantially cylindrical" refers to one having an outer surface that is large enough to expand the inner lumen of the tubular organ and maintain the expanded state during expansion.

Therefore, for example, if the lumen holding part 11a has a spiral cross section as in the second country, from its diameter reduced state, as shown in FIG. 2(B).
The lumen holding part 11b is formed by forming a cylindrical shape into a substantially cylindrical shape with an enlarged diameter or a mesh-like shape as shown in FIG. 3(A). In short, the diameter can be made smaller when introduced into a tubular organ and when taken out from a tubular organ, and when indwelling it can be made smaller due to its elasticity), due to temperature changes, or due to external force. Any material that can be expanded to ensure the inner diameter of the tubular organ may be used.

Figure 4 (B) shows the lumen holding part 11 by using a wire made of, for example, a superelastic alloy, and making the tip part into a coil shape.
e, the proximal end is a straight wire 10,
This lumen holding portion 11a can be accommodated within the catheter body 12 as appropriate. That is, FIG. 4 (1) shows a state in which the lumen holding part lie is led out from the distal end of the catheter main body 12, and FIG. The figure shows a state in which the lumen holding part 1 is housed.
When the wire 1a is led out from the catheter body 12, it naturally expands into a coiled shape due to its elasticity, as shown in FIGS. As shown in Figure (B), the lumen holding part lie is housed in the catheter body 12 while being pressed and stretched by the distal end of the catheter body 12.

In addition, in the 4th country (B), 13 is the catheter base, and a fluid injection port (not shown) or a reverse valve (not shown) to prevent blood outflow is provided here. It's okay.

Example: As a wire and a lumen holding part, a device for securing the inner diameter as shown in Fig. 1 is integrally made of Kel titanium alloy).
Furthermore, by post-processing, part of the wire was made into a superelastic alloy, and the lumen holding part was made into a shape memory alloy. The diameter of the wire was 0.6 m in a straight line, and it was made to gradually become thinner from around 30 m from the tip toward the tip. The lumen holding part is made of a shape memory alloy wire with a wire diameter of 0.1 m, and is approximately coiled in a stretched state, and has an outer diameter of 4 m at temperatures above 40°C.
The coil shape is memorized. This device for securing the inner diameter was assembled into the catheter shown in FIG. 4, and the dog's blood vessels were placed and retrieved according to the following procedure.

(1) Indwell a 52-induroducer in the femoral artery using the standard method under complete anesthesia.

(2) Carry out hemophosphate (200 units/yu).

(3) Select the right superficial carotid artery using a 5F catheter equipped with a device to secure the inner diameter. In this case, the right superficial carotid artery was selected using only the 5F catheter without the device for securing the inner diameter inserted, and then the device for securing the inner diameter with the lumen holding part extended was introduced into the blood vessel through the lumen of the catheter. Good too.

(4) Next, with the lumen holding part led out from the tip of the catheter body, warmed saline at 45°C is injected from the catheter lumen, and the lumen holding part of the device for securing the inner diameter is memorized. It is placed in the blood vessel in the expanded diameter coiled state.

(5) Remove the catheter and complete the placement.

(6) After 30 minutes, the 5F catheter is placed and introduced into the blood vessel along the inner diameter securing device.

(7) Advance the catheter body until the tip of the catheter is located in front of the lumen holding part (coil) of the device for securing the inner diameter.

(8) Pull the lumen holding part into the lumen of the catheter body while pulling the wire and stretching the coiled part. (9) Pull out the catheter from the blood vessel and complete recovery of the device for securing the inner diameter.

(Effects of the Invention) As described in detail above, in the present invention, a straight wire is connected to a cylindrical lumen holding part that can be expanded and contracted in the radial direction as a means for securing the inner diameter of the inner lumen of a tubular organ. The lumen holding part can be easily placed in the affected part of the lumen of the tubular organ, or can be retrieved from the indwelling part.

Therefore, problems such as biocompatibility when permanently indwelling the tube as in the past are solved, and even if restenosis occurs in the affected area, the lumen can be easily expanded again.

[Brief explanation of the drawing]

1 (incl. 1) is a plan view of the device for securing the inner diameter of the inner lumen of a tubular organ according to the present invention 1c, and FIG. The partially cutaway plan views shown in Figures 2 (A) and (B) and the third location (B) are modified examples corresponding to Figures 1 (A) and (B), respectively. Figure (4) is a perspective view showing the reduced state, and the second
Figures (B) and 3 (B) are respectively perspective views showing the expanded state, and Figure 4 (B) shows the state in which the device for securing the inner diameter of the inner lumen of a tubular organ is incorporated into the catheter, Fourth
FIG. 4(B) is a side view showing a state in which the lumen holding part is led out from the tip of the catheter main body, and a state in which the lumen holding part is housed in the lumen of the catheter main body. In the figure, 10--wire, 11. lla, llb. 11e...Lumen holding part, 12...Catheter main body,
13... Catheter base. Applicant's Representative Patent Attorney Takehiko Suzue Figure (A) Figure 2 (A) Figure (A) Figure (B) Figure (B) Figure (B) Figure 4 (B)

Claims (6)

[Claims] (1) An instrument for securing the inner diameter of a tubular organ, comprising a straight wire and a cylindrical lumen holding part attached to the tip of the wire and capable of expanding and contracting in the radial direction. (2) The inner diameter securing device according to claim 1, wherein the lumen holding portion is made of a metal selected from shape memory alloy, stainless steel, piano wire, superelastic alloy, tungsten alloy, platinum or an alloy containing platinum, and silver-palladium alloy. . (3) The inner diameter securing device according to claim 1 or 2, wherein at least a portion of the lumen holding portion is radiopaque. (4) A catheter body comprising a catheter main body and the inner diameter securing device according to claim 1, and the lumen holding portion of the inner diameter securing device is inserted into and removably inserted into the catheter main body. Characteristic lumen preservation catheter. (5) The lumen-maintaining catheter according to claim 4, further comprising a check valve at the base of the catheter body. (6) The lumen-maintaining catheter according to claim 4 or 5, further comprising a fluid injection port at the base of the catheter body.