JPH0556984A - Obstruction removing catheter - Google Patents

Abstract

PURPOSE:To allow the efficient excision of the obstructions sticking to the inside wall of a blood vessel without flawing the inside wall of the blood vessel by providing at least one projections, the inside surfaces of which are curved and hollowed, on the outside surface of a cylindrical member, forming blade surfaces on the opened front end surfaces of the projections and forming small holes within the curved and followed base surfaces. CONSTITUTION:A tube 2 is inserted into the blood vessel and an aperture 14 is installed in the obstruction in the blood vessel. A wire 4 is then extended by a wire operating jig 6 to shift the aperture 14 surface toward the inside wall side of the blood vessel. A rotating member 3 is then rotated to rotate an excision member 1 and to excise the obstructions in the apertures 14. The obstructions are removed by the blade surfaces 8 of the curved and hollowed projections 20 of the excision member 1 and the greater part of the obstruction pieces are gathered into an obstruction collecting chamber through the hollow part of the rotating member 3 from the small holes 18 formed on the base surfaces of the projections 20. The obstruction pieces are partly gathered into the obstruction collecting chamber from the inside cavity of the tube 2. These obstruction pieces are discharged from a discharge port 5 connected to a vacuum source.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a catheter for removing an embolus attached to the inner wall of a blood vessel.

[0002]

2. Description of the Related Art Blood flow is inhibited when coagulated blood (thrombus) or atheroma and the like consisting of calcium and cholesterol (hereinafter collectively referred to as embolus) adheres to the inner wall of a blood vessel. For example, if the blood flow in the coronary artery is blocked by an embolus, myocardial infarction occurs,
Also, if the limb peripheral blood vessels are occluded, the limbs may be amputated. Therefore, it is required to remove such an embolus at an early stage, and various cutting methods have been conventionally performed.

For example, in Japanese Patent Publication No. 57-501167, a balloon catheter is inserted into a blood vessel and the balloon of the catheter is expanded in the blood vessel to enlarge the inner diameter of the thinned blood vessel. A method of securing blood flow by using Sako 3 is introduced. However, this method simply enlarges the inner diameter of the thinned blood vessel to secure the blood flow, so that restenosis may occur even if the blood flow can be secured temporarily. US Pat. No. 4,940,067 discloses that such a balloon catheter has been overcome.
In the specification, a catheter is inserted into a blood vessel, an embolus of the inner wall of the blood vessel is introduced into an opening provided in a side wall of the catheter, and a metal cutter inserted in the catheter is rotated forward. A so-called atherectomy-angiogenesis method, in which the introduced embolus is excised, is introduced and has attracted attention.

As shown in FIG. 4, this embolus-cutting catheter is connected to a cutter 36 for cutting off an embolus at the tip of an outer tube 31 into which an inner tube 32 is inserted, and an inner tube. The drive shaft 33 is inserted in the hub 32, and the tip of the drive shaft 33 is a cutter 36.
The sliding part 35 of is installed. Drive shaft 33 is an inner tube
A head 34 projecting from 32 and leading inside the blood vessel is formed at the tip, and the cutter 36 together with the outer tube 31 is rotationally advanced toward the sliding portion 35 by rotationally advancing the drive shaft 33 to embolize the inside of the blood vessel. Are to be excised. Then, in the method of removing the embolus in the blood vessel, as shown in FIG. 5, first, the opening 40 of the catheter is installed at the position where the embolus 37 is present (see FIG.
5A). The wire 38 is then stretched to press the outer wall of the outer tube 31 against the inner wall of the blood vessel (Fig. 5B). Then, the cutter 36 is rotated and moved forward to open the opening 35.
The internal embolus 37 is excised (Fig. 5C). The excised embolic piece 39 is removed (FIG. 5D). The catheter opening 40 is then oriented in the opposite direction (FIG. 5E). Then, the embolism in the blood vessel is removed by repeating the operation of FIGS. 5B to 5D (FIG. 5F).

[0005]

However, in the method of advancing while rotating the cutter while cutting off the embolus, the catheter must be rotated inside the blood vessel, and the tip of the catheter is cut off. Since it needs to be advanced beyond the position, it has a drawback of damaging the inner wall of the blood vessel. An object of the present invention is to provide a catheter which can efficiently remove an embolus attached to the inner wall of a blood vessel without damaging the inner wall of the blood vessel.

[0006]

According to the present invention, there is provided an elongated tube comprising a tubular member having an opening in a side wall and having a bottom end, the tube being inserted into the tube and at the tip side. Cylindrical cutting member arranged at a position corresponding to the opening of the tube, an embolic collection chamber having an enlarged inner diameter on the rear side, and an elongated cylindrical rotating member having a rotary drive shaft connected to its rear end. An outlet port for discharging an embolus that is branched from the embolus collection chamber and connected to a vacuum source; and an outer wall of the tube near the opening, which is provided on the side opposite to the opening of the tube. In an embolization excision catheter comprising an expansion / contraction means for moving to the inner wall direction of a blood vessel, the excision member comprises a cylindrical member having an outer surface provided with at least one projection having a curved hollow inside. The open tip surface is a blade surface, and a small hole is formed on the curved hollow base surface. Are, formed by at least one small hole provided in the side wall of the rotary member embolectomy catheter - is ether. Further, the present invention is the embolus excision catheter in which the expanding and contracting means is a balloon or a wire.

[0007]

The present invention inserts an embolization catheter into a blood vessel,
By rotating the cutting member provided at the tip of the rotary drive shaft connected to the motor, the embolus attached to the inner wall of the blood vessel is cut by the blade surface of the curved hollow projection of the cutting member. Most of the excised embolic pieces are collected from the small hole formed on the base surface of the projection of the excision member through the hollow part of the rotating member to the embolus collection chamber, and part of them are collected from the tube lumen. It is collected in a chamber and discharged from a discharge port connected to a vacuum source.

[0008]

EXAMPLES An example of the present invention will be described below with reference to examples. 1 is an explanatory view of an embolus excision catheter of the present invention, FIG. 2 is a partially cutaway sectional view of the embolus excision catheter of the present invention, and FIG. 3 is an example of a protrusion of the embolus excision catheter of the present invention. FIG. 4 is a partially cutaway sectional view of a conventional embolus excision catheter, and FIG. 5 is an explanatory view of a method of using the embolus excision catheter of FIG. 4. In the figure, 1 is a cutting member, 2 is a tu
3 is a rotating member, 4 is an expanding / contracting means (wire), 5 is a discharge port, 6 is a wire operating jig, 7 is a wire, 8 is a blade surface of a cutting member, 9 is a connecting part, 10 Is a motor, 11 is a battery, 12 is a switch, 13 is an embolus collection chamber, 14 is an opening, 15 is a tip housing, 16 and 17 are bottomed parts, 18 and 19 are small holes, 20 is a protrusion. Show.

An example of the present invention will be described with reference to FIGS. The tip of the tube 2 is composed of a bottomed portion 16,
An opening 14 is provided in the sidewall adjacent to 16. The rear end of the tube is connected to a drive unit main body containing a motor 10 and a battery 11 via a connecting part 9 such as a screw connector. At the rear end side of the tube 2, there is an embolus collection chamber 13 having an enlarged inner diameter, and a discharge is connected to a tube (not shown) for branching from the side wall of the collection chamber 13 and discharging the embolism. Port 5 is installed. At least one small hole is provided on the side wall of the rotary member 3, but it is preferable that the small hole is formed only on the side wall of the rotary member 3 of the embolus collection chamber 13 as shown in FIG. Then, the embolus piece that has passed through the hollow portion of the rotary member 3 from the small hole 18 of the cutting member 1 and the embolus piece that has passed through the inner cavity of the tube 2 are collected in the embolus collection chamber 17, and the embolus piece is removed by the vacuum source. It is removed via the drain port 5 and the embolus drain tube. In addition, the expansion / contraction means 4 is provided on the distal end side of the embolus collection chamber 17.
The wire operation jig 6 for operating the wire
It is provided by branching from the side wall.

The rotary member 3 is inserted into the tube 2, and the cutting member 1 is connected to the tip of the rotary member 3. The rear end is connected to the motor 10 of the main body of the rotary drive unit through the connecting part 9 so that the rotary member 3 rotates in the tube 2 in conjunction with the rotation of the motor 10. There is. The cutting member 1 is provided on the tip side of the rotating member 3 and is installed in the opening 14 of the tube 2, and the blade surface 8 of the cutting member 1 rotates when the cutting member 1 rotates.
Is formed within a range not exceeding the outer diameter of. That is, since the rotating blade of the cutting member 1 is inside the outer circumference of the tube 2, it is possible to prevent the inner wall of the blood vessel from being damaged by the rotation of the cutting member 1. The cutting member 1 is formed by providing at least one protrusion 20 on the outer surface of a cylindrical member. FIG. 3 is a perspective view of the protrusion 23, in which the open end surface of the protrusion 20 is formed by the blade surface 8 and has the shape of a cat's ear with a curved hollow inside, and the inside has a curved hollow inside. The base surface, which is the side wall of the cylindrical member of the protrusion 20, is composed of the small hole 18,
The embolus piece cut off by the blade surface 8 is sucked into the hollow portion of the cylindrical cutting member 1. In FIG. 3, the protrusion 20 has a shape like a cat's ear, but it may have a semi-hemispherical shape with a curved hollow inside. The blade edge of the blade surface 8 may be upright at a right angle to the outer line of the cylindrical member, but it is preferable that the blade edge of the blade surface 8 is bent in the rotation direction of the cutting member 1 because it does not damage the inner wall of the blood vessel. The cutting member 1 is manufactured, for example, by forming at least one small hole 18 in a metal sheet to form a built-up thick portion on a protrusion and then forming the sheet into a cylindrical shape. .. The tip end side of the cutting member 1 is connected to the cylindrical bottomed portion 17 and is supported so that the support shaft of the rotating member 3 does not move during rotation.

On the opposite side of the opening 14 of the tube 2, there is provided an expanding / contracting means 4 for moving the outer wall of the tube near the opening 14 toward the inner wall of the blood vessel. In FIG. 1, a wire is used as an expansion / contraction means, and a wire-manipulating jig 6 provided on the rear end side of the tube 2 passes through a wire-7 and then a wire-4.
Expands and contracts. When the tube 2 is inserted into the blood vessel, the wire 4 contracts and contacts the outer surface of the tube 2, but the opening 14 of the tube 2 is installed at the embolization position in the blood vessel. -When the wire 4 is extended by the operating jig 6, the surface of the opening 14 of the tube 2 moves to the inner wall side of the blood vessel, and the outer wall near the opening of the tube 2 comes into contact with the inner wall of the blood vessel. Although a wire is used as the expansion / contraction means 4 in FIG. 1, a balloon may be used as the expansion / contraction means. In FIG. 1, the contracted balloon is in contact with the outer surface of the tube 2 and air is press-fitted into the balloon by an air-pressing jig instead of the wire-operating jig 6. By expanding the balloon, the surface of the opening portion 14 of the tube 2 moves toward the inner wall of the blood vessel, and the outer wall near the opening of the tube 2 comes into contact with the inner wall of the blood vessel. An embolus is introduced into the opening 14 and the switch
By actuating 12, the rotating member 3 rotates, which causes the cutting member 1 to rotate and cut the emboli in the opening 14. Then, the tube 2 is rotated so that the opening 14 faces the opposite surface. This operation is also possible by rotating the entire catheter, but the bottom of the tube 2 has a bottom.
A tip housing 15 including 16 may be provided and connected to the tube 2 behind the opening 14 via a connecting piece. In such a catheter, rotation of the opening 14 of the tube 2 need only rotate the tip housing 15.

The cutting member 1 has a cylindrical shape with a bottom end, and is similarly connected to a cylindrical rotating member 3 at a cylindrical portion. At the rear end side of the tube 2, there is an embolus collection chamber 13 having an enlarged inner diameter, which is connected to a discharge port 5 for discharging the embolus. At least one small hole is provided in the side wall of the rotating member 3, and the cut embolus piece is removed not only in the tube 2 but also in the hollow portion of the cylindrical rotating member 3. In particular, if small holes are provided only in the excision member 1 and the embolus collection chamber 13, the embolus removal position inside the rotating member 3 is fixed, and most of the embolus pieces pass through the hollow portion of the rotating member 3 and are discharged. .. The cylindrical rear end of the rotating member 3 extends to the embolus collecting chamber 13, and the rotating member 3 behind the embolus collecting chamber 13 has a cylindrical shape. The side wall of the cutting member 1 is provided with at least one small hole 18. At least one small hole is formed in the side wall of the rotary member 3 of the embolus collection chamber 13.
19 is provided, and the embolus piece that has passed through the cylinder of the rotating member 3 is removed from the small hole 19. In the embolus collection chamber 13, not only the embolus from the small hole 19 but also the embolus in the tube 2 lumen is discharged.
Is discharged through. In FIG. 1, the rotating member 3 has a structure inserted in the tube 2. However, by disposing an inner tube outside the rotating member 3, the cut-out embolic piece is attached to the outer periphery of the rotating member 3. It is preferable because it can be prevented from adhering to. The tube 2 is preferably made of plastic such as Teflon, polyethylene, polypropylene, polyimide, polyvinyl chloride, ABS resin, polyurethane,
The rotating member 3 is preferably made of metal such as stainless steel, polyimide, polyurethane, polyvinyl chloride, polyolefin, polyester, plastic such as polyamide, ceramic, or the like. Further, the cutting member 1 is preferably made of metal, ceramic, hard plastic or the like.

[0013]

According to the embolus excision catheter of the present invention, the embolus attached to the inner wall of the blood vessel is excised by the excision member only by rotation of the rotating member inserted in the tube. Once locked in position, it does not move back and forth during embolization. To that end, embolization is performed inside the tube,
Very little damage to the inner wall of blood vessels. Further, most of the embolus cut off by the blade surface of the cutting member is sucked from the inner surface of the curved hollow projection into the small hole in the base surface thereof, and enters the embolus collection chamber through the hollow portion of the rotating member. Since it is discharged from the discharge port, the load on the motor for driving the rotation of the rotating member due to the plug attached to the inner surface of the tube is unlikely to increase.

[Brief description of drawings]

FIG. 1 is an explanatory view of an embolization excision catheter of the present invention.

FIG. 2 is a partially cutaway sectional view of an embolus excision catheter of the present invention.

FIG. 3 is a perspective view of a protrusion of the embolus excision catheter of the present invention.

FIG. 4 is a partially cutaway cross-sectional view of a conventional embolus cutting catheter.

5 is an explanatory diagram of a method of using the embolus excision catheter of FIG. 4. FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cutting member 2 Tube 3 Rotating member 4 Expansion / contraction means (wire) 5 Ejection port 6 Wire-operation jig 7 Wire-8 Cutting surface of cutting member 9 Connection part 10 Motor 11 Battery 12 Switch 13 Embolus collection chamber 14 Opening 15 Tip housing 16, 17 Bottomed part 18, 19 Small hole 20 Projection

Claims (2)

[Claims] 1. An elongated tube comprising a tubular member having an opening on a side wall and having a bottom end; a tube inserted into the tube and corresponding to the opening of the tube on the tip side. A cylindrical cutting member arranged at a position, an embolic collection chamber having an enlarged inner diameter on the rear side, and an elongated cylindrical rotating member having a rear end connected to a rotary drive shaft; branching from the embolic collection chamber Then
A discharge port for discharging an embolus connected to a vacuum source;
In the embolus excision catheter provided on the side opposite to the opening of the tube and for expanding and contracting the outer wall of the tube near the opening toward the inner wall of the blood vessel, the cutting member is a cylindrical member. An outer surface is provided with at least one inner surface having a curved hollow projection, and an opening tip surface of the projection is a blade surface, and a small hole is formed at a base surface of the curved hollow projection. An embolus cutting catheter having at least one small hole formed in the side wall of the rotating member. 2. The embolus excision catheter according to claim 1, wherein the expansion and contraction means comprises a balloon or a wire.