JPH0630943A - Embolectomy catheter - Google Patents

Abstract

PURPOSE:To enable the collecting of thrombolic pieces efficiently without being scattered outside a catheter by arranging an outer tube expandable almost over the entire length outside a slender tube with an open tip thereof housing a filter at the tip part thereof and an extrusion means to extrude the filter outward. CONSTITUTION:A side wall opening 14 is set in the direction of an embolus 25 and a physiological saline is injected into an inner tube 4 to expand so that the side wall opening 14 is kept in contact with the embolus 25 while blood is stopped at a sound blood vessel point behind the embolus 25. Then, an extrusion means 19 is operated to force a filter 6 in a tip chamber 21 out at a tip opening 15 and subsequently, the filter 6 is expanded to press a blood vessel wall 24. Then, a rotary means 3 is driven to rotate so that an excision member 1 is turned to excise the embolus 25 with a cutter 8. The embolic pieces thus cut are moved backward with a notch 22 of the rotary member 3 and by vacuum absorption to collect. The embolic pieces scattered on the tip side of a catheter are trapped with the filter 6.

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 emboli) 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,
In addition, gangrene occurs when the limb peripheral blood vessels are occluded. for that reason,
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, since this method simply enlarges the inner diameter of the thinned blood vessel to secure blood flow, there is a risk of restenosis even if blood flow is temporarily secured. US Pat. No. 4,940,067 claims that such a balloon catheter has been overcome.
In the specification, a catheter is inserted into a blood vessel, an opening provided in the side wall of the catheter is arranged at the position of the embolus on the inner wall of the blood vessel, and a metal cutter inserted in the catheter. A so-called atherectomy-angiogenesis method of rotating and advancing to remove the introduced embolus has been introduced and has been attracting attention.

As shown in FIG. 5, this embolus-cutting catheter is connected to a cutter 36 for cutting off an embolus at the tip of an outer tube 31 in 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 portion 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 by rotating the drive shaft 33 forward, the cutter 36 together with the outer tube 31 is rotated forward toward the sliding portion 35 to embolize the blood vessel. Are to be excised. Then, in the method of removing the embolus in the blood vessel, as shown in FIG. 6, first, the opening 40 of the catheter is installed at the position where the embolus 37 is present (see
6A). 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. 6B). Then, the cutter 36 is rotated and moved forward to open the opening 35.
The internal embolus 37 is excised (Fig. 6C). The excised embolic piece 39 is removed (FIG. 6D). The catheter opening 40 is then oriented in the opposite direction (FIG. 6E). Then, the embolism in the blood vessel is removed by repeating the operations of FIGS. 6B to 6D (FIG. 6F). Further, in JP-A-62-266046, an inflatable balloon is provided in place of the wire 38 shown in FIG.
A device that presses the opening of the tell at the position of the embolus to remove the embolus attached to the blood vessel wall has been introduced.

[0005]

However, due to the expansion and contraction of the wire provided on the opposite side of the catheter opening and the expansion of the balloon, the catheter opening is pressed to the position of the embolus to the vessel wall. The device to remove the attached embolus is
Since the expansion and contraction of the wire and the expansion of the balloon are performed only near the opposite side of the catheter opening, the catheter opening does not completely adhere to the embolus, and the blood comes from the catheter tip side. There is a risk that the removed embolic pieces will flow to the ground and scatter. An object of the present invention is to provide an embolus excision catheter which efficiently excises an embolus attached to the inner wall of a blood vessel and collects and ejects the excised embolus piece without scattering it outside the catheter.

[0006]

SUMMARY OF THE INVENTION That is, according to the present invention, there is provided an elongated tube having an opening at a side wall and an opening at an end thereof, the housing accommodating a filter; An inflatable outer tube provided; a cutting member inserted into the tube and disposed at a position corresponding to an opening portion of the tube at a tip side; a tube tip opening of the filter; The embolus cutting catheter comprises a pushing means for pushing the portion outward. Further, the present invention is the embolus excision catheter in which the outer tube is provided over the entire length of the tube excluding the side wall on the opening side of the tube in the distal direction from the vicinity of the opening. . Further, the present invention is the embolus excision catheter, wherein the embolus excision catheter is provided with a hole for pouring a contrast medium into a blood vessel in the tube. Further, according to the present invention, in the embolus cutting catheter, the cutting member comprises a cutter for cutting the embolus, and an embolus cutting catheter provided with a rotating member equipped with a screw-shaped notch behind the cutter. It is tell. Furthermore, the present invention is the embolus cutting catheter, wherein the cutting member comprises an elongated cylindrical rotating member,
A cutter for cutting off an embolus is provided at its tip, and the embolus cutting catheter is formed so that the cut embolus is discharged from the inside of the rotating member. Further, the present invention is the embolus excision catheter, wherein the embolus excision catheter is provided with an embolus collection chamber having an enlarged inner diameter on the rear side of the tube.

[0007]

The present invention inserts an embolized catheter into a blood vessel,
By pushing the filter housed in the tube tip through the tip opening, the filter expands inside the vessel. The removed embolus pieces scattered in the direction of the filter are captured by the surface of the filter and are prevented from scattering in the direction of the blood vessel on the tip side of the filter. The tube opening is placed in the embolus of the blood vessel, and the tube opening is pressed against the embolus site by injecting the liquid into the outer tube, while blood is collected at the healthy blood vessel site behind the embolus. Mostly hemostasis. Then, by pressing the switch, the rotating member connected to the motor rotates while moving back and forth,
The embolus attached to the inner wall of the blood vessel is excised by the blade surface of the excision member by rotationally moving the excision member provided at the tip thereof. After the excised embolic piece is excised, it is moved rearward, for example, through the troughs of the screw-shaped notch, is collected in the embolic collection chamber, and is discharged from the discharge port connected to the suction pump.

[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 showing an example of the present invention, FIG. 2 is a partially cutaway sectional view showing an essential part of the embolus excision catheter, and FIG. 3 is FIG. FIG. 4 is a sectional view taken along line XX of the embolus excision catheter, and FIG. 4 is the embolus excision catheter of FIG.
FIG. 6 is a sectional view taken along line YY of FIG. 5, FIG. 5 is a partially cutaway sectional view of a conventional embolus excision catheter, and FIG. 6 is an explanatory view of a method of using the embolus excision catheter of FIG. 7 is a partially cutaway sectional view showing an essential part of an embolus excision catheter according to another embodiment of the present invention, and FIG. 8 is a perspective view of a projection of the embolus excision catheter of FIG. In the figure, 1 is a cutting member, 2 is a tube, 3 is a rotating member, 4 is an outer tube, 5 is a discharge port, 6 is a filter, 7 is a contrast agent injection tube, and 8 is a blade surface of the cutting member. ,
9 is a partition wall, 10 is a motor, 11 is a battery, 12 is a switch, 13 is an embolus collection chamber, 14 is a side wall opening, 15 is a tip opening, 16 and 26 are wire manipulation jigs, 17 is a Liquid injection port
G, 18 is a hole for contrast agent, 19 is extrusion means, 20 is a compartment, 21 is a distal chamber, 22 is a notch, 23 is a contrast agent injection port, 24 is a blood vessel wall,
25 is an embolus, 27 is a wire, 28 is a protrusion, 29 is an embolus discharge small hole, and 30 is a connecting member.

An example of the embolus excision catheter of the present invention will be described with reference to FIGS. The tip of the tube 2 is shown in FIG.
As shown in FIG. 3, the partition wall 9 forms a distal end chamber 21 with the distal end opening 15. A filter 6 is housed in the tip chamber 21 as shown in FIG. The filter 6 in FIG. 2 is in a state in which it is pushed out from the distal end opening portion 15 and expanded to the inner wall of the blood vessel wall 24 by the wire 19 as the pushing means. The filter 6 captures the embolic pieces scattered on the tip side of the catheter and prevents the embolic pieces from flowing in the blood vessel direction in front of the filter. The filter 6 is stored in the distal chamber 21 in a compressed state, and when pushed out of the distal chamber 21, the filter 6 is expanded in a state of pressing the blood vessel wall 24.
After the embolization, the filter 6 was inserted into the distal chamber 21 and
The catheter is removed from the blood vessel. Therefore, the filter
6 is preferably a stretchable material that is easily compressed and inserted into the distal chamber 21 and expands to the blood vessel wall 24 when pushed out from the distal chamber 21, for example, nylon mesh, and in addition, foamed plastic, sponge rubber, knitted fabric, Examples include non-woven fabrics. The filter 6 is moved in and out of the front end chamber 21 by the operation of the pushing means 19, for example, a wire attached to the filter 6. In FIG. 1, the wire 19 is adapted to push or pull the filter 6 by operating the wire operating jig 16. The partition wall on the tip side of the compartment 20 is provided with a contrast agent hole portion 18 for pouring the contrast agent into the blood vessel, and the contrast agent injected from the contrast agent injection port 23 is a contrast agent injection tube. After entering the compartment 20 via 7, the contrast agent is discharged from the contrast agent hole 18 into the blood vessel and is used to confirm the embolization position in the blood vessel.

An opening 14 is provided in the side wall adjacent to the front end chamber 21, and the rear end of the tube 2 has a motor 10 and a battery 11 built therein via a screw-shaped connecting member 30. It is connected to the main unit. 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 tube (not shown) for branching from the side wall of the collection chamber 13 and discharging the embolus piece. A discharge port 5 is installed for this purpose. Discharge port 5
Is connected to a vacuum device, and the excised embolus is collected in the embolus collection chamber 13 by vacuum suction and discharged. The rotating member 3 is inserted into the tube 2 and the cutting member 1 is connected to the tip thereof. The cutting member 1 is installed in the opening 14 of the tube 2, and its blade surface 8 is made up of a metal cutter in FIG. 1, for example, one having a cylindrical outer surface provided with a cutter. The outer diameter of the blade surface 8 is formed within the range that does not exceed the outer diameter of the tube 2, thereby preventing the blood vessel wall 24 from being damaged by the rotation of the cutting member 1. The rotating member 3 in FIG. 1 has a threaded notch 22 formed on a cylindrical outer surface, and the embolus 25 is cut by the rotation of the cutting member 1. The embolus pieces are collected in the chamber 13 and the embolus pieces are discharged by the vacuum source.
And removed via the embolus evacuation tube. Rotating member 3
The rear end is connected to the motor 10
The rotating member 3 rotates in the tube 2 in conjunction with the rotation of the motor 10 and can move back and forth. The embolus 25 attached to the blood vessel wall 24 is excised by moving forward and backward while rotating. When the tube 2 is formed of a thermoplastic resin, heat is generated by the rotation of the cutting member 1 to soften and deform the tube 2, or when the cutting member 1 is rotationally moved.
In order to prevent the risk of removing the inner wall of the tube 2, a metal cylindrical body may be provided on the inner wall of the tube 2.

An outer tube 4 is provided on the outer surface of the tube 2 over substantially the entire length of the tube. The outer tube 4 is a tube 2 when the embolization catheter is inserted into the blood vessel.
When the opening 14 of the tube 2 is placed at the embolization position in the blood vessel, the liquid injection port
A liquid is injected into the outer tube 4 from the valve 17, the outer tube 4 expands, 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 becomes the inner wall of the blood vessel. While contacting, the outer wall of the tube 2 behind the opening 14 also comes into close contact with a healthy blood vessel to prevent blood from flowing into the opening 14. As the liquid, physiological saline, physiological saline mixed with a contrast agent, or the like is used. 3 and 4 are cross-sectional views of the embolus cutting catheter of FIG. 2 when the outer tube 4 is expanded, and FIG.
FIG. 4 is a cross-sectional view at the location of FIG. In FIG. 1, the outer tube 4 is provided over the entire length of the tube excluding the tube side wall on the side wall opening 14 side in the distal direction from the vicinity of the side wall opening 14. In addition, the outer tube 4 is provided only in the vicinity of the side wall on the opening side of the side wall opening 14 except for the distal end chamber 2
1, the side wall on the side opposite to the side wall opening and the entire side of the tube rearward of the side wall opening 14 may be provided.
It is preferable that the outer tube 4 expands when liquid is injected,
Examples thereof include synthetic rubbers such as silicone rubber, SEBS and SIS, thermoplastic resins such as polyurethane, polyvinyl chloride and polyolefin, and natural rubber. The embolus 25 is introduced into the opening 14, and the rotary member 3 is rotated by operating the switch 12, whereby the cutting member 1 is rotated and the embolus 25 in the opening 14 is cut. Tube 2 is Teflon, polyethylene, polypropylene, polyimide,
A plastic such as polyvinyl chloride, ABS resin or polyurethane is preferable, and the rotating member 3 is made of metal such as stainless steel, polyimide, polyurethane, polyvinyl chloride,
It is preferably made of a plastic such as polyolefin, polyester or polyamide, or ceramic. Further, the cutting member 1 is preferably made of metal, ceramic, hard plastic or the like.

In order to operate the embolus excision catheter of FIGS. 1 to 4, first, the catheter inserted into the blood vessel is provided with the contrast agent injected from the contrast agent injection port 23 at the tip of the compartment 20. The embolus 25 in the blood vessel is dispersed from the hole 18 for the contrast medium that is dispersed in the blood vessel.
Check the position of. Then the side wall opening 14 in the direction of the embolus 25
Is installed and physiological saline is injected from the fluid injection port 17 to inflate the outer tube 4 so that the side wall opening 14 is in contact with the embolus 25, and the tube behind the side wall opening 14 is placed.
The outer wall of the bulge is placed in close contact with healthy blood vessels. . Thereafter, the wire operating jig 16 is operated to push the filter 6 in the tip chamber 21 through the tip opening portion 15 of the tip chamber 21 and expand the filter 6 so that the filter 6 is pressed against the blood vessel wall 24. Then, by activating the switch 12, the motor 10
Rotates and the rotating member 3 rotates in the tube 2 in conjunction therewith. Then, the cutting member 1 at the tip of the rotating member 3 is also rotated and the embolus 25 is cut by the cutter 8. The cut embolic pieces are collected by the notch 22 of the rotary member 3 and the vacuum suction in the rear embolic collection chamber 13 and discharged from the discharge port 5.

FIG. 7 is a partially cutaway sectional view showing an essential part of an embolus excision catheter according to another embodiment of the present invention, in which the rotary member 3 of the embolus excision catheter of FIG. 1 has a cylindrical shape. The cutting member 1 is an embolization cutting catheter having a projection shape. A catheter having a compressed filter 6 housed at the front end and an embolus collection chamber 13 having an enlarged inner diameter on the rear end side.
A discharge port 5 for discharging the emboli is installed by branching from the side wall of the collecting chamber 13 to the main body. 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. 7. Then, the embolus piece that has passed through the hollow portion of the rotary member 3 from the small hole 28 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 13, and the embolus piece is removed by the vacuum source. Discharge port 5 and embolus discharge tube
It is removed after passing through. Further, a wire 27 for pushing the filter 6 out of the tip opening of the tube 2 and a wire operating jig 26 for operating the same are provided on the tip side of the embolus collecting chamber 13 while branching from the side wall of the tube. ing.

The rotating member 3 is inserted into the tube 2, and the cutting member 1 is connected to the tip of the rotating member 3. The rear end is connected to the motor of the main body of the rotary drive through a connecting part,
The rotating member 3 rotates in the tube 2 in conjunction with the rotation of the. 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 its blade surface 28 does not exceed the outer diameter of the tube 2 when the cutting member 1 rotates. It is formed within the range. 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 as shown in FIG. FIG. 8 is a perspective view of the protrusion 20,
The opening end surface of the protrusion 20 is composed of the blade surface 8, has a shape like a cat's ear with a curved hollow inside, and is a side wall of the cylindrical member of the protrusion 20 with a curved hollow inside. The surface is a small hole
It has a function of suctioning the embolus piece cut by the blade surface 8 into the hollow portion of the cylindrical cutting member 1. In FIG. 7, the protrusion 20
Has a shape like a cat's ear, but 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 thickened portion which is built up into a protrusion, and then forming the sheet into a cylindrical shape. . The tip side of the cutting member 1 has a cylindrical bottomed portion.
It is connected to 17 and is supported so that the spindle of the rotating member 3 does not move during rotation.

An outer tube 4 is installed outside the tube 2 over substantially the entire length of the tube. Figure 7 shows tube 2
The state where the outer tube 4 is expanded by injecting physiological saline from the liquid injection port 17 provided on the rear end side is shown. . When inserting the tube 2 into a blood vessel, the outer tube 4 is in close contact with the outer surface of the tube 2, but the opening 14 of the tube 2 is placed at the embolization position in the blood vessel, By injecting physiological saline from the injection port 17, the opening 14 of the tube 2 is opened.
The outer wall in the vicinity moves to the inner wall side of the blood vessel, and the outer wall behind the opening 14 of the tube 2 comes into close contact with the inner wall of the blood vessel. There is an embolus in the opening 14, and the rotating member 3 rotates to rotate the cutting member 1 to cut off the embolus in the opening 14.

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 of the embolus collecting chamber 13, and the cut embolus pieces are removed not only in the tube 2 but also in the hollow portion of the cylindrical rotating member 3. It 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 rotary member 3 is fixed, and most of the embolus pieces pass through the hollow portion of the rotary member 3 and are discharged. . The cylindrical rear end of the rotating member 3 has an embolus collection chamber 13
Up to and behind the rotary member 3, the rotary member 3 has a cylindrical shape. The side wall of the cutting member 1 has at least one small hole 28
Is provided. At least one small hole 29 is provided in the side wall of the rotary member 3 of the embolus collection chamber 13, and the plug piece passing through the cylinder of the rotary member 3 is removed from the small hole 29. Embolus collection room 13
Then, not only the embolus from the small hole 29 but also the embolus piece in the inner cavity of the tube 2 is discharged through the discharge port 5.

[0017]

The catheter for embolization according to the present invention expands the outer tube 1 provided over substantially the entire length of the tube to push the side wall open portion of the tube to the embolized portion and the embolized portion. Since the inner wall of the healthy blood vessel located further behind is also pressed, the blood is almost hemostasised in the healthy blood vessel, and the embolus attached to the inner wall of the blood vessel is excised in the hemostasis state at the side wall open portion of the tube. Also, the embolic pieces scattered toward the tip of the tube are expanded by being pushed out from the tip of the tube.
Since the emboli are not adsorbed on the tube, the emboli attached to the inner wall of the tube are efficiently excised, collected and discharged in the catheter.

[Brief description of drawings]

FIG. 1 is an explanatory view of an embolus excision catheter showing an example of the present invention.

FIG. 2 is a partially cutaway sectional view showing a main part of the embolus excision catheter of FIG.

FIG. 3 is a cross-sectional view taken along line XX of the embolization catheter of FIG.

4 is a cross-sectional view taken along the line YY of the embolization catheter of FIG.

FIG. 5 is a partially cutaway cross-sectional view of a conventional embolization catheter.

6 is an explanatory view of a method of using the embolus excision catheter of FIG. 5. FIG.

FIG. 7 is a partially cutaway sectional view showing an essential part of an embolus excision catheter showing another embodiment of the present invention.

8 is a perspective view of a protrusion of the embolus excision catheter of FIG. 7. FIG.

[Explanation of symbols]

 1 cutting member 2 tube 3 rotating member 4 outer tube 5 discharge port 6 filter 7 contrast agent injection tube 8 cutting surface of cutting member 9 partition wall 10 motor 11 battery 12 switch 13 embolus collection chamber 14 sidewall Opening 15 Tip opening 16, 26 Wire-manipulating jig 17 Liquid injection port 18 Contrast medium hole 19 Extrusion means 20 Separation chamber 21 End chamber 23 Contrast medium injection port 24 Blood vessel wall 25 Embolus

Claims (6)

[Claims] 1. An elongate tube having an opening on a side wall and having an opening at a tip end thereof and containing a filter; and an inflatable outer tube provided on the outside of the tube over substantially the entire length. A cutting member inserted into the tube and located at a position corresponding to the opening of the tube on the tip side; and an extrusion for pushing the filter outward from the tube tip opening. An embolization catheter comprising means. 2. The outer tube has a tube extending from the vicinity of the opening toward the tip.
The embolus cutting catheter according to claim 1, which is provided over the entire length of the tube excluding the side wall on the opening side of the tube. 3. The embolus excision catheter according to claim 1, wherein a hole for pouring a contrast medium into a blood vessel is provided in the tube. 4. The embolus cutting catheter according to claim 1, wherein the cutting member is a cutter for cutting an embolus, and a rotating member provided with a threaded notch is provided behind the cutter. . 5. The cutting member is composed of an elongated cylindrical rotary member, and a cutter for cutting the emboli is provided at the tip of the rotary member so that the cut embolus is discharged from the inside of the rotary member. The embolization catheter according to claims 1 to 3. 6. The embolus resection catheter according to claim 1, wherein an embolus collection chamber having an enlarged inner diameter is provided on the rear side of the tube.