JPH07124251A - Blood filter for indwelling in artery - Google Patents

Abstract

PURPOSE:To make a blood filter capable of indwelling in an artery and removable therefrom, and collect an arrested tissue piece or the like without any omission. CONSTITUTION:This blood filter 1 for indwelling in an artery has a collapsible and expandable filter member 5 forming arrest space with the rear end open and the forward end projected, and a filter open/close member for expanding and collapsing the member 5. The filter 1 has more specifically a core material 2, a ring-type member 6 fitted thereto in such state as capable of travel, a filter retaining section 4 formed out of a plurality of elastic members, with one end fixed to the material 2 and the other end fixed to the member 6, a collapsible and expandable filter member 5 forming arrest space with the rear side of the material 2 open, and projected toward the forward end thereof, and a filter member open/close mechanism for moving the member 6 along the axial direction of the material 2, and for opening and closing the member 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a blood filter that can be placed in an artery. Specifically, the present invention relates to an intraarterial indwelling blood filter used when an extracorporeal circulation circuit is formed to perform surgery on the heart or the like.

[0002]

2. Description of the Related Art In recent years, due to an increase in arteriosclerotic diseases and heart diseases, a method of performing an operation by forming an extracorporeal circulation circuit has been widely used. The extracorporeal circulation circuit consists of a blood removal cannula connected to the ascending and descending veins of the heart, a blood removal circuit connecting the blood removal cannula and the heart-lung machine, and an artificial blood vessel that removes oxygen and carbon dioxide from the blood and sends blood. It is composed of a cardiopulmonary device, a blood supply cannula connected to the ascending artery or the iliac artery, and a blood return circuit connecting the blood supply cannula and the artificial heart-lung machine. In other words, due to extracorporeal circulation, blood flowing out of the blood removal cannula connected to the ascending and descending veins of the heart without passing through the heart is deoxygenated and carbon dioxide removed, and then connected to the ascending or iliac arteries of the heart. The blood is returned to the patient by the blood supply cannula.

[0003]

When connecting a blood supply cannula, the root of the ascending artery of the heart is clamped, and the blood supply cannula is often connected to the immediate peripheral side of the artery.
In this case, the ascending artery arch is flushed with the blood flowing into the ascending artery from the blood return cannula. Then, in the case of a patient who has arterial effect in the blood vessel region near the ascending artery arch, due to blood flushing, tissue fragments of the arterial effect nest and vascular wall deposits are peeled off from the blood vessel wall and pass through the carotid artery to the brain. There is a risk of inflow, circulation, and inflow into the heart coronary arteries. Furthermore, if these pieces of tissue are trapped in microvessels, there is a risk of causing functional disorders. The same is true when connected to the iliac artery, and there is a risk that the arterial effect lesion tissue of the abdominal aorta or the thoracic aorta will flow into the coronary arteries of the heart.

Up to now, a filter for removing thrombus to be inserted into a vein has been proposed, for example, Japanese Unexamined Patent Publication (Kokai) No. Hei 3
-210273, JP-A-61-41444 and the like. However, since both of them are intended to be placed in a vein, they cannot be directly applied to an artery whose blood flow is opposite. In addition, JP-A-61-41
If the one disclosed in Japanese Patent No. 444 is applied to an artery, there is a risk that the tissue pieces trapped on the outer surface of the mesh filter at the rear end side will be separated from the outer surface together with the folding of the filter and flow out into the blood vessel. Therefore, an object of the present invention is to provide an intraarterial indwelling blood filter that can be placed in and removed from an artery and can be collected without detaching a captured tissue piece or the like.

[0005]

To achieve the above object, there is provided a foldable and expandable filter member having a rear end side opening and a trapping space protruding toward the front end side, and expansion and foldability of the filter member. It is a blood filter for indwelling in an artery having a filter opening / closing member. And
The intra-arterial indwelling blood filter preferably has a filter storage member that stores the filter member in a folded state and that allows the filter member to project from the tip and be stored again.

Further, what achieves the above object is that a core material, a ring-shaped member movably provided on the core material, one end fixed to the core material, and the other end fixed to the ring-shaped member. And a fold and expansion fixed to the filter holding part, which forms a trapping space which is open at the rear end side of the core material and which projects toward the tip end side of the core material, and which is formed by a plurality of elastic members. A filter member whose rear end side face is in close contact with the inner wall of the artery in a further expanded state, and a filter member opening / closing mechanism for moving the ring-shaped member in the axial direction of the core member to open / close the filter member It is a blood filter for indwelling in an artery having a. The filter member opening / closing mechanism is preferably a ring-shaped member moving member having one end fixed to the ring-shaped member and the other end extending to the rear end side of the core member. Further, it is preferable to have a fixing member for fixing the ring-shaped member moving member to the core member. The filter part opening / closing mechanism includes a spring member having one end fixed to the core member or the filter holding member and the other end fixed to the ring-shaped member at the tip end side of the core member, and the filter member is folded. It is preferable to have a filter accommodating member that can be accommodated in a closed state, and that can project and re-accommodate the filter member from the tip.

In addition, what achieves the above-mentioned object is a main body tube having a fluid inflow lumen therein, and can be expanded and contracted or folded by inserting the main body tube, and substantially adheres to an inner wall of an artery in an expanded state. A hollow annular member, one end of which is attached to the main body tube, communicates with the lumen of the main body tube, and the other end of which extends to the rear end side of the main body tube and is attached to the hollow annular member,
A plurality of hollow annular member expanding tubes communicating with the inside of the hollow annular member, a plurality of elastic members provided along the hollow annular member expanding tube, and an elastic member fixing member provided at the tip of the plurality of elastic members. And a filter holder fixed to the hollow ring-shaped member and a filter member that is foldable and expandable. The elastic member of the filter holder is expanded by the hollow ring-shaped member. In the absence state, the filter member is brought into a folded state in the vicinity of the main body tube, and the hollow annular member is expanded so that the other end of the elastic member is separated from the main body tube to expand the filter member. Is a blood filter for indwelling in an artery.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A blood filter for indwelling an artery according to the present invention will be described with reference to the embodiments shown in the drawings. FIG. 1 is a cross-sectional view of one embodiment of the blood filter for intraarterial indwelling of the present invention, and FIG. 2 is an external view of the blood filter of FIG. 1 in an expanded state. FIG. 3 is a cross-sectional view of another embodiment of the blood filter for indwelling in the artery of the present invention, and FIG. 4 is an external view of the blood filter of FIG. 3 in an expanded state. 5 is a cross-sectional view of another embodiment of the blood filter for intraarterial indwelling of the present invention, and FIG.
It is an external view of the state which the filter member of the blood filter of FIG. 5 expanded.

The blood filter 1 for indwelling in an artery of the present invention comprises:
It has a foldable and expandable filter member 5 that is open on the rear end side and forms a trapping space that projects to the front end side, and a filter opening / closing member that expands and folds the filter member 5. Since the filter member 5 is expandable and collapsible, it can be placed on and removed from the inner wall of the artery, and furthermore, a piece of tissue flowing in the artery can be captured on the inner surface of the filter member 5, and the filter can be filtered again after capture. By folding the member 5, the tissue piece trapped on the inner surface can be collected without detaching, which is an excellent effect as an intraarterial indwelling filter.

Specifically, as shown in FIG. 1, a blood filter 1 for indwelling in an artery has a core material 2, a ring-shaped member 6 movably provided on the core material 2, and one end of the core material 2. A filter holding portion 4 made of a plurality of elastic members fixed to the ring-shaped member 6 and the other end fixed to the ring-shaped member 6, and a rear end side of the core material 2 is opened to form a trapping space protruding toward the front end side of the core material 2. In addition, the filter member 5 fixed to the filter holding portion 4 is foldable and expandable, and the side surface of the rear end of the filter member 5 is in close contact with the inner wall of the artery in the expanded state, and the ring-shaped member 6 is connected to the shaft of the core material. And a filter member opening / closing mechanism that opens and closes the filter member 5 by moving the filter member 5 in a predetermined direction. In the blood filter for indwelling in an artery shown in FIG. 1, the filter member opening / closing mechanism has a ring-shaped member 6 having one end fixed to the ring-shaped member 6 and the other end extending to the rear end side of the core member 2. Is formed by the main body tube. Further, a fixing member 9 for fixing the ring-shaped member moving member 7 at an arbitrary position of the core material is provided. Therefore, this blood filter 1
In the above, the filter member 5 can be easily and surely expanded and folded, and can be placed in and removed from the inner wall of the artery. Furthermore, the inner surface of the filter member 5 captures a tissue piece flowing in the artery. By re-folding the filter member 5 after capturing, the tissue piece captured on the inner surface can be removed without detaching.

The core material 2 forms a fixed portion on the front end side of the filter holding portion 4, and is inserted through the inside of the main body tube 7 and the ring-shaped member 6 to form the central axis of the blood filter of the present invention. ing. As the core material 2, a material having some flexibility and some rigidity such as stainless steel wire, piano wire, and high-tensile steel for spring is used, and its length is about 100 to 800 mm. Ring-shaped member 6
Is for holding a rear end side of a filter holding portion 4 which will be described later, is provided so as to insert the core material 2 therein and is movable with respect to the core material 2, and an insertion hole through which the core material 2 is inserted. have. The tip of the body tube 7 is fixed to the rear end of the ring-shaped member 6. Further, a tip portion 3 is formed at the tip of the core material 2, and the tip portion 3 has a rounded shape so as not to damage the blood vessel wall or the like during insertion. The tip of the elastic member 4a that constitutes the filter holding portion 4 is fixed to the tip 3 of the core 2 or the tip of the core 2. The rear end of the elastic member 4a is
It is fixed to the ring-shaped member 6. Filter holder 4
Is composed of a plurality of elastic members 4a. As shown in FIG. 1, in a normal state, is substantially parallel to the core member 2, and the intermediate portion of the elastic member 4a is also separated from the core member 2 by a large amount. Absent. Further, as shown in FIG. 1, it is in a state of being housed in the filter member housing member 8.

A plurality of filter holding portions 4, for example, 2 to
The elastic member 4a is formed of about 8 elastic members 4a, preferably 3 to 6, and the elastic member 4a is formed of a material having elasticity and rigidity to some extent. Specifically, the elastic member 4a includes high-tensile steel wire for spring, metal wire such as piano wire, polyamide, fluororesin (PTFE, ETF).
A synthetic resin linear body formed of a resin having a relatively high rigidity such as E) is preferably used. Filter holder 4
As the length of the elastic member 4a, in other words,
It is preferably about 25 to 70 mm. Then, as shown in FIG. 1, the filter member 5 is fixed and is in a folded state on the tip side from the intermediate portion of the filter holding portion 4. In the filter holding part 4, the ring-shaped member 6 moves toward the tip end side of the core material 2, so that the elastic member 4 a is curved as shown in FIG. 2 and the filter member 5 is expanded.
As a result, the filter member 5 forms a trapping space that is open at the rear end side of the core material 2 and projects toward the front end side of the core material 2. As shown in FIG. 2, the filter member 5 is fixed to the elastic member 4a, and the opening 5a is provided in the filter member 5a.
Is formed into a substantially circular shape when fully extended. Therefore, when the filter member 5 is expanded due to the bending of the elastic member 4a, the filter member 5 has a space between the elastic members 4a. And
In this blood filter, since arterial blood flows from the opening 5a side of the filter member 5 to the tip side, the blood flow causes the opening 5a of the filter member 5 or a portion in the vicinity thereof to substantially adhere to the inner wall of the blood vessel. The diameter of the filter holder 4 when expanded is preferably about 10 to 30 mm.

The filter member 5 is formed in a substantially conical shape as shown in FIG. 2 in order to exhibit the above-mentioned functions. And as the diameter of the opening, 10 to 30 m
About m is preferable. Then, due to the end of the bending of the filter holding portion, the space between the elastic members 4a of the filter member 5 is folded, and the tissue piece captured on the inner surface of the filter member 5 is stored in the folded filter member 5, It does not flow into blood when the blood filter 1 is removed from the artery. As the filter member 5, a synthetic resin, for example,
A mesh-like one formed of polyolefin fiber (polypropylene fiber, polyethylene fiber), polyamide fiber, polyester fiber or the like is preferable. The mesh-like material may be woven cloth or non-woven cloth. The mesh size of the filter member 5 is preferably about 40 to 500 μm, more preferably 50 to 300 μm, and particularly preferably 100 to 200 μm. Since blood when the blood filter 1 is used is basically heparinized, it is considered that no thrombus is generated by contact with the filter member, but for safety, the filter member is used. 5a may be antithrombotic treated. As the antithrombotic treatment, coating or fixing of an antithrombotic material is considered, and as the antithrombotic material, a known material,
For example, poly (2-hydroxyethyl methacrylate), polyhydroxyethyl acrylate, hydroxypropyl cellulose, methyl vinyl ether maleic anhydride copolymer, block copolymer of HEMA-ST-HEMA, thrombolytic substance (urokinase, streptokinase, etc.), Thrombosis-inhibiting substances (polysaccharides such as heparin, prostaglandins, antithrombin agents, etc.) are preferable. As the antithrombotic treatment method, a method of applying the above-mentioned substance, a method of binding by an ionic bond or a covalent bond, a method of mixing in a material, and the like are suitable. In particular, it is preferable to bond them.

As described above, the main body tube 7 has the ring-shaped member 6 attached to the tip thereof, has a lumen for inserting the core member 2 therein, and extends to the rear end side of the core member 2. The rear end of the core material 2 projects from the rear end of the main body tube 7. Body tube 7
Holds the vicinity of the rear end portion or the intermediate portion and moves the ring-shaped member 6 to the core material 2 by moving it toward the tip side of the core material 2.
It is provided to move to the tip side of the. That is,
The main body tube 7 constitutes a moving mechanism for the ring-shaped member 6. As the main body tube 7, a flexible tube such as a soft vinyl chloride resin, a polyolefin elastomer (for example, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, a mixture of polypropylene and polybutene, etc.), polyamide elastomer, polyester Flexible synthetic resin tubes such as elastomer and polyurethane elastomer, and rubber tubes such as silicone rubber and latex rubber are preferably used. The length of the main body tube 7 is preferably about 100 to 750 mm.

For the same reason as that of the above-mentioned filter member, it is preferable to perform antithrombogenic treatment on the portion that comes into contact with blood, specifically, the outer surface and inner surface of the main body tube 7. Similarly, it is preferable that the ring-shaped member 6, the core member 2, and the tip portion 3 are also subjected to antithrombotic treatment. As the antithrombogenic treatment method and the antithrombotic material, the above-mentioned ones can be preferably used. Further, a fixing member 9 for fixing the ring-shaped member moving member 7 at an arbitrary position of the core member is provided at the rear end of the main body tube 7. Specifically, the fixing member 9
Is composed of a fixed ring member 9a attached to the rear end of the main body tube 7, and a rotary ring 9b having a threaded portion screwed into the ring-shaped fixed member 9a. The fixed ring member 9a internally has a tapered screw hole whose diameter decreases toward the front end side, and the rotating ring 9b is screwed into the screw hole, and as the screwing progresses, the rotating ring 9b moves in the direction of the core material 2 It has a curved protruding portion 9c. Then, as the screwing progresses, the protruding portion 9c of the rotating ring 9b approaches the side of the core material 2 and finally grips the core material 2, whereby the core material 2 is
The rotating ring 9b is fixed.

Further, in order to make insertion and removal of the blood filter 1 into and from the artery easier, the filter member 5 can be stored in a folded state, and the filter member 5 can be projected and re-stored from the tip. Filter storage member 8
It is preferable to have In this blood filter 1, the filter housing member 8 houses the blood filter 1 on the distal side of the ring-shaped member 6, and has a slightly expanded diameter distal end housing portion 8a and a main body housing that extends near the rear end of the main body tube 2. And a portion 8b. As the storage member 8, a flexible tube such as a soft vinyl chloride resin, a polyolefin elastomer (for example, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, a mixture of polypropylene and polybutene, etc.), polyamide elastomer, polyester A flexible synthetic resin tube such as an elastomer or a rubber tube such as silicone rubber or latex rubber is preferably used. The length of the storage member is preferably about 70 to 750 mm.

Next, the blood filter of the present invention shown in FIG. 3 will be described. The blood filter 20 of this embodiment has the same basic configuration as that shown in FIG. 1, but is different in the filter member opening / closing mechanism. Specifically, FIG.
As shown in FIG. 1, an intraarterial indwelling blood filter 20 includes a core member 22, a ring-shaped member 26 movably provided on the core member 22, one end fixed to the core member 2, and the other end ring-shaped member. A filter holding portion 24 made of a plurality of elastic members fixed to the core member 26 and a rear end side of the core material 22 are opened to form a trapping space protruding toward the front end side of the core material 22, and the filter holding portion 2
4 is foldable and expandable, and the filter member 25, whose rear end side surface is in close contact with the inner wall of the artery in the expanded state, and the ring-shaped member 26 are moved in the axial direction of the core member. And a filter member opening / closing mechanism for opening / closing 25. Then, the filter portion opening / closing mechanism includes a filter member 25 and a spring member 21 having one end fixed to the core member 2 or the filter holding unit 24 at the tip end side of the core member 2 and the other end fixed to the ring-shaped member 26. It is configured by a filter housing member 28 that is housed in a folded state and that allows the filter member 25 to project from the tip and be housed again. Therefore, in this blood filter 20, the filter member can be easily and surely expanded and folded, and further, can be placed on and removed from the inner wall of the artery, and further flow in the artery on the inner surface of the filter member. The tissue piece can be captured, and by refolding the filter member after the capture, the tissue piece captured on the inner surface can be removed without detaching.

The core material 22 forms a fixed portion on the tip side of the filter holding portion 4 and is inserted through the inside of the main body tube 7 and the ring-shaped member 6 to form the central axis of the blood filter of the present invention. ing. The core material 2 is made of stainless steel wire, piano wire, high-tensile steel wire for spring, or the like having some flexibility and a certain degree of rigidity, and has a length of about 100 to 800 mm. . In the blood filter of this embodiment, the core member 22 is extruded toward the distal end side at the base end portion of the core member 22 to remove the filter member 25.
Are projected from the filter storage member 28. Further, after the use, the filter member 25 is pulled into the filter housing member 28 by pulling the core material 22 toward the rear end side at the base end portion of the core material 22.
It is stored inside. Therefore, as the core material 22, it is preferable to use one having high torque transmission. Therefore, the core material 22 is preferably a piano wire or a high-strength steel wire for spring. The ring-shaped member 26 is used for the filter holding portion 24 described later
It holds the rear end side, is provided so that the core member 22 is inserted therein and is movable with respect to the core member 22, and has an insertion hole through which the core member 22 is inserted.

At the tip of the core material 22, a tip portion 23
Is formed, and the distal end portion 23 has a rounded shape so as not to damage the blood vessel wall or the like during insertion. Then, the tip portion 23 of the core material 22 or the core material 22
At the tip of the elastic member 24 that constitutes the filter holding portion 24.
The tip of a is fixed. The rear end of the elastic member 24a is fixed to the ring-shaped member 26. The filter holding portion 24 is composed of a plurality of elastic members 24a, and as shown in FIG. 3, in a state of being housed in the filter housing member 28, it is substantially parallel to the core member 22, and the elastic member 24a The middle portion is not too far from the core material 2. The filter holding portion 24 is formed of a plurality of elastic members 24a, for example, about 2 to 8, preferably 3 to 6, and the elastic members 24a are formed of a material having a certain degree of elasticity and rigidity. There is. Specifically, the elastic member 24a includes high-tensile steel wire for spring, metal wire such as piano wire, polyamide, fluororesin (PTFE, ETF).
A synthetic resin linear body formed of a resin having a relatively high rigidity such as E) is preferably used. Filter holder 2
As the length of the elastic member 24a, in other words, the length of the elastic member 24a is preferably about 25 to 70 mm.

A spring member 21 having one end fixed to the core 2 or the filter holding portion 24 and the other end fixed to the ring-shaped member 26 is provided on the tip side of the core 2.
The spring member 21 is fixed in a stretched state, and when the spring member 21 projects from the filter housing member 28, the spring member contracts.
The elastic member 24a forming the part is curved. Further, when the spring member 21 is housed in the filter housing member 28 again,
The spring member is in a stretched state. The expanded diameter of the filter holding portion 4 is preferably about 10 to 30 mm, and a spring member having such a diameter is selected and fixed. As shown in FIG. 3, a filter member 25 is fixed in a folded state on the tip side of the intermediate portion of the filter holding portion 24. The filter holding portion 24 moves the ring-shaped member 26 toward the distal end side of the core material 22,
In other words, as described above, the filter holding portion 24 and the spring member 21 project from the filter housing member 28, and the elastic member 24a is curved as shown in FIG. Expand 25. As a result, the filter member 25 forms a trapping space that is open at the rear end side of the core material 22 and projects toward the front end side of the core material 22. As shown in FIG. 4, the filter member 5 is fixed to the elastic member 24a, and further, the opening 25a.
Are formed to have a substantially circular shape when the filter member 25 is completely expanded. Therefore, when the filter member 25 is expanded due to the bending of the elastic member 24a, the filter member 25 has a space between the elastic members 24a. In this blood filter 20, since arterial blood flows from the opening 25a side of the filter member 25 to the distal end side, the blood flow causes the opening 25a of the filter member 25 or a portion in the vicinity thereof to substantially adhere to the inner wall of the blood vessel.

The filter member 25 is formed in a substantially conical shape as shown in FIG. 4 in order to exhibit the above-mentioned functions. The diameter of the opening is 10 to 30.
About mm is suitable. Then, due to the end of the bending of the filter holding portion, the space between the elastic members 24a of the filter member 25 is folded, and the tissue piece captured on the inner surface of the filter member 25 is stored in the folded filter member 25, It does not flow into the blood when the blood filter 20 is removed from the artery. As the filter member 25, the above-mentioned one can be preferably used. Filter storage member 28
As described above, with the operation of the core member 22, the tip end side portion of the ring-shaped member is projected from the storage member 28, the filter member 25 is expanded, and the function of folding the filter member 25 again is assisted. Furthermore, by providing this storage member 28, the insertion and removal of the blood filter 20 into and from the artery can be facilitated.

In the blood filter 20, the filter storage member 28 has a slightly enlarged diameter front end storage portion 28a for storing the blood filter 1 on the front end side of the ring-shaped member 26 and the vicinity of the rear end of the core member. Main body storage 8b extending
And have. As the storage member 8, a flexible tube, for example, a flexible vinyl chloride resin, a flexible synthetic resin tube such as a polyolefin elastomer (eg, polyethylene elastomer, polypropylene elastomer), polyamide elastomer, polyester elastomer, silicone rubber, latex rubber, etc. The rubber tube of is preferably used. The length of the storage member is preferably about 70 to 750 mm.

Further, at the rear end of the storage member 28, a fixing member 29 for fixing the storage member 28 at an arbitrary position of the core material.
Is provided. Specifically, the fixing member 29 is the fixing ring member 29 a attached to the rear end of the storage member 28.
And a rotary ring 29b having a threaded portion screwed into the ring-shaped fixing member 29a. And
The fixed ring member 29a internally has a tapered screw hole whose diameter decreases toward the tip side, and the rotating ring 29b is screwed into the screw hole, and as the screwing progresses, the rotating ring 29b moves in the direction of the core 22. It has a curved protruding portion 29c. Then, as the screwing progresses, the protruding portion 29 of the rotating ring 29b.
c approaches the core material 22 side, and finally grips the core material 22, whereby the rotating ring 29b is fixed to the core material 22. Then, for the same reason as that of the blood filter 1 of the above-described embodiment, a portion that comes into contact with blood, specifically, the filter member 25, the filter housing member 28, and the ring-shaped member 2.
6, it is preferable to perform antithrombotic treatment on the outer surface and the inner surface of the core material 22 and the tip portion 23. As the antithrombogenic treatment method and the antithrombotic material, the above-mentioned ones can be preferably used.

Next, the blood filter of the embodiment shown in FIG. 5 will be described. The blood filter 40 of this embodiment has a body tube 41 having a fluid inflow lumen 42 therein.
A hollow annular member 47 that can be expanded and contracted or folded by inserting the main body tube 41, and is in close contact with the inner wall of the artery in the expanded state;
A plurality of hollow annular members for communicating with the lumen 42 of the body tube 41, the other end extending to the rear end side of the body tube 41, attached to the hollow ring member 47, and communicating with the hollow ring member interior 47. A filter holding portion 44 including a tube 43, a plurality of elastic members 44a provided along the hollow annular member expanding tube 43, and an elastic member fixing portion 44b provided at a tip portion of the plurality of elastic members 44a, and a filter. A foldable and expandable filter member 45 fixed to the holding portion 44 and the hollow annular member 47.
And the elastic member 44a of the filter holder 44 is
In a state where the hollow annular member 47 is not expanded, the filter member 45 is brought close to the main body tube 41, and the hollow annular member 47 is expanded so that the other end of the elastic member 44a is separated from the main body tube 41. However, the filter member 45 is expanded. The main body tube 41 has a check valve 49 that is always closed at the rear end and opens when the fluid injector 51 is connected.

The main body tube 41 is a tube body having a fluid inflow lumen 42 therein, and the filter holding portion 4
4 to form a fixed portion on the distal end side of the blood filter 4 of the present invention.
It forms the basic skeleton of zero. As the main body tube 41, a flexible tube such as a soft vinyl chloride resin, a polyolefin elastomer (for example, a polyethylene elastomer, a polypropylene elastomer, an ethylene-propylene copolymer, an ethylene-vinyl acetate copolymer, a mixture of polypropylene and polybutene, etc.) ), Flexible synthetic resin tubes such as polyamide elastomer, polyester elastomer and polyurethane elastomer, and rubber tubes such as silicone rubber and latex rubber are preferably used. The length of the main body tube 41 is preferably about 100 to 800 mm.

The hollow ring-shaped member 47 can be expanded and contracted or folded by inserting the main body tube 41, and is in close contact with the inner wall of the artery in the expanded state. The hollow annular member 47 has a hollow annular member expanding tube 43 inside.
Is communicated with the lumen 42 of the main body tube 41, and the hollow annular member is expanded by the fluid introduced into the lumen 42 of the main body tube 41. Hollow annular member 47
The elastic material may be formed of a stretchable material and expanded by expansion by the inflow of fluid, or may be formed of a material having almost no elasticity and expanded to the formed shape by the inflow of fluid. . Preferably,
It is to be formed of a material having a certain degree of elasticity. By using such a material, the adhesion to the inner wall of the artery becomes more reliable, and the inner wall is less likely to be damaged. Further, the outer diameter of the hollow annular member 47 when expanded is preferably about 10 to 30 mm. Examples of stretchable materials include polyolefin elastomers (eg, polyethylene elastomer, polypropylene elastomer, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, polypropylene-polybutene mixture, etc.), polyamide elastomer, polyester elastomer, polyurethane elastomer, etc. Rubber such as stretchable synthetic resin, silicone rubber, and latex rubber can be preferably used. Examples of materials having low elasticity include polyolefins such as polyethylene, polypropylene and ethylene-propylene copolymers, polyesters such as polyethylene terephthalate, polyvinyl chloride, ethylene-vinyl acetate copolymers and cross-linked ethylene-vinyl acetate. Thermoplastic resins such as copolymers, polyurethane and polyphenylene sulfide are suitable.

The hollow annular member expanding tube 43 is attached to the tip of the main body tube 41 so as to branch as shown in FIG. 5, and communicates with the lumen 42 of the main body tube 41. And the other end is the body tube 4
1 extends to the rear end side and is attached to the hollow annular member 47,
And it communicates with the inside. It is preferable that a plurality of the expansion tubes 43 be provided, and about 2 to 8 tubes are preferable, and 3 to 6 tubes are particularly preferable. The filter holding portion 44 has a plurality of elastic members 44a provided along the hollow annular member expansion tube 43 and an elastic member fixing portion 44b provided at the tip of the plurality of elastic members 44a. . In the normal state, the elastic member 44a is substantially parallel to and close to the main body tube as shown in FIG. The fluid flowing through the lumen 42 fills the hollow annular member expanding tube 43 and the hollow annular member 47, and further expands the hollow annular member 47, so that as shown in FIG. The member 44a is pushed by the hollow annular member 47, and the other end thereof spreads and is separated from the main body tube 41. The tip portion of the fixing portion 44b has a rounded shape so as not to damage the blood vessel wall or the like during insertion.

The elastic member 44a is made of synthetic resin having elasticity and rigidity to some extent, for example, polycarbonate, polystyrene, polyamide, etc.
Further, it is possible to consider one that is entirely formed of piano steel, stainless steel, or the like, or one in which the fixing portion 44b is formed of synthetic resin and the elastic member 44a is formed of piano steel, stainless steel, or the like. The length of the filter holder 44,
In other words, the length of the elastic member 44a is 25 to
About 70 mm is suitable. The filter holding part 44 is preferably formed of a plurality of elastic members 44a, for example, about 2 to 8, preferably 3 to 6, and the hollow annular member expanding tube 43 is a filter holding part. It is preferable that the elastic member 44a is fixed to the inner surface of the elastic member 44a. By doing so, the elastic member 44a
Receives a force from both the hollow annular member 47 and the expansion tube 43 when the hollow annular member 47 is expanded, so that the deformation thereof is facilitated and the filter member 45 described later is provided.
The expansion of is also certain.

Then, as shown in FIG. 5, a filter member 45 is provided on the tip side of the intermediate portion of the filter holding portion 44.
It is fixed in the folded state. As described above, the filter holding portion 44 is deformed by the expansion of the hollow annular member 47 and expands the filter member 45. As a result, the filter member 45 is opened at the rear end side of the main body tube 41 and forms a trapping space protruding toward the front end side of the main body tube 41. As shown in FIG. 6, the filter member 45
Is fixed to the elastic member 44a and the hollow annular member 27, and is formed to have a substantially circular cross section when the filter member 45 is completely expanded. For this reason, even if the hollow annular member 47 expands and comes into close contact with the inner wall of the artery, the filter member 45 can be operated by the elastic members 44a.
In some cases, there is a space between them. In this blood filter 40, since arterial blood flows from the rear end side to the front end side of the filter member 45, the blood flow causes the rear end side of the filter member 45 or a portion in the vicinity thereof to substantially adhere to the inner wall of the blood vessel.

The filter member 45 is formed in a substantially conical shape as shown in FIG. 6 in order to exhibit the above-mentioned functions. Then, due to the end of the bending of the filter holding portion 44, the elastic members 4a of the filter member 45 are folded between the elastic members 4a, and the tissue pieces captured on the inner surface of the filter member 45 are stored in the folded filter member 5. When the blood filter 40 is removed from the artery, it does not flow into the blood. As the filter member 45, a mesh-shaped member formed of synthetic resin, for example, polyolefin fiber (polypropylene fiber, polyethylene fiber), polyamide fiber, polyester fiber or the like is preferable. The mesh-like material may be woven cloth or non-woven cloth. Also,
The mesh size of the filter member 45 is 40 to 500.
μm is preferable, and more preferably 50 to 300 μm.
m, and particularly preferably 100 to 200 μm.

As shown in FIG. 5, the main body tube 41 has a check valve 49 which is always closed at the rear end and opens when a fluid injector (eg, syringe) 51 is connected. Then, in the blood filter 40 of this embodiment,
Before use, by syringe, inside the blood filter 40 (lumen 42, expansion tube 43, inside hollow annular member 47)
By reducing the amount of air by suction, the tip of the blood filter becomes easy to insert into the artery. Then, after being inserted into the artery, a fluid such as physiological saline or an X-ray contrast medium is injected by a syringe to form a hollow annular member 47.
And expand the expansion tube.

[0032]

Next, the operation of the blood filter for indwelling an artery according to the present invention will be described with reference to FIGS. 1, 2, 7 and 8.
After the chest is opened, the blood filter 1 of the present invention is inserted in the upper part of the ascending artery 52 and upstream of the aortic arch. At the time of insertion, as shown in FIG. 1, the filter member 5
Is not expanded (the filter member 5 is housed in the housing member 8), the tip side is inserted downstream of the artery. Then, as shown in FIGS. 2 and 7,
The filter member 5 is projected from the tip of the filter housing member 8. Then, the rotating ring 9b of the fixed member 9 attached to the rear end of the main body tube 7 is loosened, and the main body tube 7 is pushed toward the distal end side while the core material 2 is held by hand. As a result, the elastic member 4a of the filter holding portion 4 bends and the filter member 5 expands. And holding part 4a
At a position in which the abutment is almost in contact with the inner wall of the artery, the rotating ring 9b of the fixing member 9 is rotated to fix the rotating ring 9b to the core material. Thereby, the expanded state of the filter member 5 is maintained. Then, since the arterial blood flows from the opening side of the filter member 5 toward the distal end side, the peripheral portion of the filter member 5 or the vicinity thereof is pushed by the blood flow and adheres to the inner wall of the artery, and the state shown in FIG. Becomes

As shown in FIG. 7, the blood supply cannula 53 is the ascending artery 52 of the heart, and the blood filter 1
Insert more upstream, insert a blood removal cannula (not shown) into the ascending and descending veins of the heart, connect the blood supply cannula 53 and the blood removal cannula with a heart-lung machine using a tube,
Create an extracorporeal circuit. After completion of the open-heart surgery, the rotating ring 9b of the fixing member 9 attached to the rear end of the main body tube 7 is loosened, and the main body tube 7 is pulled toward the rear end side while holding the core material 2 by hand. As a result, the elastic member 4a of the filter holding portion 4 is in a linear state, and the filter member 5 is in a state of being folded between the elastic members 4a. Then, the tissue piece captured on the inner surface of the filter member 5 is captured inside by the folding of the filter member 5. Further, the filter member 5 is stored again in the filter storage member 8. Then, the blood filter 1 is removed from the artery.

When the ascending arteriosclerotic lesion of the ascending artery is significant, the above-described ascending artery is not used as shown in FIG.
It is also possible to insert a blood supply cannula into one of the iliac arteries and insert the blood filter 1 of the present invention from the other iliac artery, as shown in FIG. Therefore, it is preferable that the blood filter 1 has a length that can be used by inserting it from the iliac artery. In this blood filter 1, as shown in FIG. 8, the filter member is expanded and complements the arterial effect lesion tissue pieces of the abdominal aorta or the thoracic aorta, so that they are prevented from flowing into the coronary arteries of the heart. .

[0035]

The blood filter for indwelling the artery of the present invention is
The filter member includes a foldable and expandable filter member that is open at the rear end side and forms a trapping space that protrudes toward the front end side, and a filter opening / closing member that expands and folds the filter member. Since the filter member is expandable and collapsible, it can be placed on and removed from the inner wall of the artery, and further, a piece of tissue flowing in the artery can be captured on the inner surface of the filter member, and after the capture, the filter member can be removed again. By folding, the tissue piece captured on the inner surface can be removed without detaching, and it has an excellent effect as an intraarterial indwelling filter.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of an embodiment of a blood filter for indwelling in an artery of the present invention.

FIG. 2 is an external view of the blood filter of FIG. 1 with a filter member expanded.

FIG. 3 is a cross-sectional view of another embodiment of the blood filter for intraarterial placement of the present invention.

FIG. 4 is an external view of the blood filter of FIG. 3 with the filter member expanded.

FIG. 5 is a cross-sectional view of another embodiment of the blood filter for intraarterial placement according to the present invention.

FIG. 6 is an external view of the blood filter of FIG. 5 with the filter member expanded.

FIG. 7 is an explanatory diagram for explaining the action of the blood filter of the present invention.

FIG. 8 is an explanatory diagram for explaining the action of the blood filter of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Blood filter for indwelling in an artery 2 Core material 3 Tip part 4 Filter holding part 4a Elastic member 5 Filter member 6 Ring-shaped member 7 Main body tube 8 Filter storage member 9 Fixing member 20 Blood filter for indwelling in an artery 40 Blood for indwelling in an artery filter

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shuzo Yamashita 1500 Inoguchi, Nakai-cho, Ashigarakami-gun, Kanagawa Terumo Corporation

Claims (1)

[Claims] 1. A foldable and expandable filter member having a rear end opening and forming a trapping space protruding toward the front end, and a filter opening / closing member for expanding and folding the filter member. Blood filter for indwelling in artery.